DESC:PORTABLE CHARGING DEVICE FOR ELECTRIC VEHICLES
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority from Indian Provisional Patent Application No. 202321036228 filed on 25/05/2023, the entirety of which is incorporated herein by a reference.
TECHNICAL FIELD
The present disclosure generally relates to a charger for an electric vehicle. Particularly, the present disclosure relates to portable device for charging electric vehicle(s).
BACKGROUND
As a result of advancements in technology, environmental concerns, and changing consumer preferences, in recent years the electric vehicles are gaining popularity among consumers for collective or personal mobility. The electric vehicles are equipped with electric motor/motors and other electrical and electronic components that are powered from a power pack in the vehicles. The power pack needs to be electrically recharged once the energy stored in the power pack is depleted. The power pack is charged from a power source that is generally located external to the vehicles.
Conventionally, the electric vehicles are charged at the designated charging stations. Such designated charging stations charge the power pack of the electric vehicle by converting the electrical energy received from the power source (grid) into electrical energy suitable to charge the power pack of the electric vehicle. The designated charging stations have chargers to convert the electrical energy, generally from AC to DC, for charging the power pack of the electric vehicle. The chargers comprise power electronic components for the conversion of the electrical energy. Such chargers are capable of quickly charging the electric vehicle, especially, electric two wheelers, within a couple of hours. However, such designated chargers (offboard chargers) require infrastructure and designated spaces for installation. Moreover, such designated chargers are not always available in the nearby areas of the electric vehicle, when the power pack is depleted. Furthermore, the electric vehicle is required to be driven to the charger, which may not always be convenient for the user of the electric vehicle due to various factors including the depleted power pack.
To overcome the issues with the designated chargers (offboard chargers), the electric vehicles nowadays are equipped with onboard chargers. The onboard chargers have the charging electronics integrated in the electric vehicle itself, wherein the electric vehicle is required to be connected to the power source with the help of a charging cable. The onboard chargers resolve the issue of the availability of the charger, as the electric vehicles with onboard chargers can be connected to any electrical outlet (including domestic or commercial) for charging the power pack of the electric vehicle. The onboard charger would convert the AC power from the electrical outlet, to DC power suitable for charging the power pack of the vehicle. However, the existing onboard chargers provides slow charging to the power pack of the electric vehicle. The electric vehicles have limited space, thus, the onboard chargers also face space constraint due to limited space available in the electric vehicle.
The portable chargers provide solutions to the problems associated with the designated chargers and the onboard chargers. However, the electronic components used in the portable chargers are small and lower rated due to which the output power of the portable charger is low leading to slow charging of the power pack of the electric vehicle. It is pertinent to note that the size of the electronic components in the portable chargers cannot be increased as it would increase the size of the portable charger making it bulky and affecting the portability of the charger. Moreover, higher rated components capable of delivering more power are also avoided as such increase in power output of the portable charger would increase the generation of heat by the portable charger. The existing portable chargers lack the capability to manage the additional heat generated due to high power operation. Such additional heat may harm the user of the charger/vehicle and may affect the portability of the charger as it would be difficult to carry a hot charger. Moreover, the existing portable chargers operates at low switching frequencies during power conversion leading to higher losses. Furthermore, the shape and size of the components of the existing portable charger restrict efficient heat extraction from the components of the portable charger.
Therefore, there exists a need for an improved portable charger for an electric vehicle that overcomes one or more problems associated as set forth above.
SUMMARY
An object of the present disclosure to provide a portable device for charging an electric vehicle with increased efficiency.
Another object of the present disclosure is to provide a portable device for charging an electric vehicle with higher power density despite compact size.
Yet another object of the present disclosure is to provide a portable device for charging an electric vehicle with improved thermal management.
In accordance with an aspect of the present disclosure, there is provided a portable device for charging an electric vehicle. The portable device comprises a connector hub configured to electrically connect the electric vehicle with a power source, a power conversion module configured to convert AC input received from the power source, a residual current detection unit, and an enclosure comprising potting compound configured to enclose the power conversion module and residual current detection unit. The power conversion module comprises an active front-end AC-DC converter, a DC-DC converter and a control unit. The DC-DC converter comprises a hybrid network configured within the DC-DC converter. The DC-DC converter comprises a high frequency DC-AC converter, a high frequency planar transformer and a high frequency AC-DC converter. The control unit is configured to control operation of the active front-end AC-DC converter and the DC-DC converter. The residual current detection unit communicably coupled with the control unit.
The present disclosure provides a portable device for fast charging of an electric vehicle. The portable device as disclosed in the present disclosure is advantageous in terms of providing portable fast charging of the power pack with increased efficiency. Beneficially, the portable device of the present disclosure operates at high frequency with reduced losses. Furthermore, the portable device as disclosed in the present disclosure is advantageous in terms of delivering higher amount of power to charge the power pack of the electric vehicle without increasing the size of the components, thus, without increasing the size and/or volume of the portable device. Furthermore, the portable device of the present disclosure is advantageous in terms of generating lesser amount of heat and better thermal management. Furthermore, the portable device of the present disclosure is advantageous in terms of reducing charging time of the power pack of the electric vehicle. Moreover, the portable device of the present disclosure is beneficially bi-directional, thus, enables vehicle to vehicle charging.
Additional aspects, advantages, features, and objects of the present disclosure would be made apparent from the drawings and the detailed description of the illustrative embodiments constructed in conjunction with the appended claims that follow.
It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.
Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams wherein:
FIG. 1 illustrates a block diagram of a portable device for charging an electric vehicle, in accordance with an embodiment of the present disclosure.
FIG. 2 illustrates a circuit diagram of a power conversion module of the portable device, in accordance with an embodiment of the present disclosure.
FIG. 3 illustrates a block diagram of a portable device for charging an electric vehicle with resonant tank, in accordance with another embodiment of the present disclosure.
FIG. 4 illustrates a circuit diagram of power conversion module of the portable device with resonant tank, in accordance with another embodiment of the present disclosure.
In the accompanying drawings, an underlined number is employed to represent an item over which the underlined number is positioned or an item to which the underlined number is adjacent. A non-underlined number relates to an item identified by a line linking the non-underlined number to the item. When a number is non-underlined and accompanied by an associated arrow, the non-underlined number is used to identify a general item at which the arrow is pointing.
DETAILED DESCRIPTION
The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. Although some modes of carrying out the present disclosure have been disclosed, those skilled in the art would recognize that other embodiments for carrying out or practicing the present disclosure are also possible.
The description set forth below in connection with the appended drawings is intended as a description of certain embodiments of portable device for charging electric vehicle and is not intended to represent the only forms that may be developed or utilized. The description sets forth the various structures and/or functions in connection with the illustrated embodiments; however, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.
The terms “comprise”, “comprises”, “comprising”, “include(s)”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, or system that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or system. In other words, one or more elements in a system or apparatus preceded by “comprises... a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.
In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings which are shown by way of illustration-specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.
The present disclosure will be described herein below with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the description with unnecessary detail.
As used herein, the terms “electric vehicle”, “EV”, and “EVs” are used interchangeably and refers to any vehicle having stored electrical energy, including the vehicle capable of being charged from a power source that is located outside the vehicle. This may include vehicles having power packs that are exclusively charged from a power source, as well as hybrid vehicles which may include power packs capable of being at least partially recharged via a power source. Additionally, it is to be understood that the ‘electric vehicle’ as used herein includes electric two-wheelers, electric three-wheelers, electric four-wheelers, electric pickup trucks, electric trucks, and so forth.
As used herein, the terms “portable charger”, “portable device” and “charger” are used interchangeably and refers to a portable system for charging the electric vehicle. The portable device is designed to convert the alternating current (AC) power into direct current (DC) power that is suitable for charging of power pack of electric vehicle. The alternating current (AC) power is received from power source including wall sockets of residential outlets. The charger supplies the high amount of current of the direct current power, to the power pack of the vehicle to quickly charge the power pack of the electric vehicle. It is to be understood that the portable device pay be plugged to any 15A power outlet to charge the electric vehicle.
As used herein, the terms “power pack”, and “battery pack” are used interchangeably and refer to multiple individual battery cells connected to provide a higher combined voltage or capacity than what a single battery can offer. The power pack is designed to store electrical energy in form of chemical energy and supply the electrical energy as needed to various devices or systems. Power pack, as referred herein are used for various purposes such as for powering electric vehicles and other energy storage applications.
As used herein, the term “connector hub” refers to component of the portable device that comprise plugs and connectors to electrically and communicably couple the portable device with the power source and/or the electric vehicle. It is to be understood that the connector hub may comprise suitable and compatible connectors for connecting the portable device with the power source and the electric vehicle.
As used herein, the term “first connector” refers to the connector meant for connecting the portable device with the power source.
As used herein, the term “second connector” refers to the connector meant for connecting the portable device with the electric vehicle.
As used herein, the term “power conversion module” refers to power electronics module of the portable device that converts the power received from the power source into power suitable for charging the power pack of the electric vehicle.
As used herein, the term “residual current detection unit” refers to a safety circuit used in the portable device that monitors the current balance, detects leakage current and triggers disconnect to prevent user from getting an electrical shock.
As used herein, the term “active front-end AC-DC converter” refers to a component to convert the alternating current (AC) power from a power source into a direct current (DC) link voltage. The converter referred herein within charger, converts AC input received from the power source, into the DC link voltage. The power source includes wall sockets of residential outlets. The converter actively shapes the AC input current waveform to be in phase with waveform of AC input voltage. The shaping of the AC input waveform corrects the power factor of the AC input. Consequently, the converter rectifies the AC input to produce the DC link voltage as output of the converter. The active front-end AC-DC converter enable bidirectional flow of power. The bidirectional switching of the switches provides for the bidirectional direction of power flow. The timing and duration of the switching of the switches is controlled to in the rectification and inversion modes of operation. The bidirectional flow of power enables bidirectional charging. The bidirectional charging may further enable the vehicle to vehicle charging.
As used herein, the term “inductor” refers to the component that stores electrical energy in the form of a magnetic field and release the stored energy as electrical energy, on requirements. The inductor used herein, is included in the active front-end AC-DC converter to store electrical energy during supply of high amplitude of the AC input current to the inductor from the power source and release the stored electrical energy during supply of low amplitude of AC input current. The alternate storing and releasing of energy shapes the waveform of AC input current to be in phase with the AC input voltage of the power source at the output of the inductor. The shaping will reduce the losses in the AC input. The timing and the magnitude of the AC input current in the inductor is adjusted to actively shape the waveform of AC input current.
As used herein, the term “rectification bridge” refers to an electronic component to convert the incoming AC current/ applied AC voltage into a pulsating DC voltage. The rectification bridge used herein in the active front-end AC-DC converter converts the AC input current/voltage received from the power source into DC voltage. The rectification bridge rectifies the AC input to convert the AC input into the DC link voltage of magnitude ranging around 380 V to 420 V i.e. high voltage. The rectification bridge includes switches including insulated gate bipolar transistors (IGBTs) or metal-oxide-semiconductor field-effect transistors (MOSFETs). The switches are arranged in a bridge configuration. The switching of the state of switches is controlled to rectify the AC input voltage/current waveform. The rectification bridge act as rectifier and performs rectification of input voltage in one direction from AC input to DC link voltage. The rectification bridge act as inverter and performs conversion of DC link voltage back to AC input in opposite direction. The timing and duration of the switching controls the generation of the DC link voltage.
As used herein, the term “first DC link capacitor” refers to the component that stores electrical energy of DC power, during periods of high voltage or power availability to be utilized during periods of lower voltage or power demand of direct voltage. The first DC link capacitor used herein, absorbs electrical energy of the pulsating DC link voltage while the amplitudes of voltage are higher. The first DC link capacitor releases electrical energy during the lower amplitudes of the DC link voltage. The alternate storage and release of electrical energy minimizes the voltage ripple from DC voltage leading to generation of a smoothen DC link voltage at the output of the first DC link capacitor.
As used herein, the term “DC-DC converter” refers to the component that converts DC voltage from one level to another level. The DC-DC converter used herein, to convert the DC link voltage of higher magnitude into a DC voltage of lower magnitude. The DC voltage is suitable to charge the power pack of the electric vehicle. The DC-DC converter converts DC link voltage into AC voltage of a high frequency ranging from 50 KHz up to 1 MHz. Consequently, the high frequency AC voltage is stepped up or stepped down to provide a variable high frequency AC output. The variable high frequency AC output is converted into DC voltage that is suitable to charge the power pack of the electric vehicle.
As used herein, the term “high frequency DC-AC converter” refers to the component that converts DC voltage into a high frequency AC link voltage. The high frequency DC-AC converter used herein in DC-DC converter, receives the DC link voltage from the active front end AC-DC converter and converts DC link voltage into AC link voltage of a high frequency. The high frequency DC-AC converter includes insulated gate bipolar transistors (IGBTs) or metal-oxide-semiconductor field-effect transistors (MOSFETs), as switches. The switching frequency and duty cycle of the state of switch, determines the frequency and the amplitude of the AC voltage at the output of the high frequency DC-AC converter.
As used herein, the term “high frequency planar transformer” refers to the transformer that steps up or steps down the AC input voltage at high frequency. The high frequency planar transformer used herein in the DC-DC converter, steps up or steps down the received high frequency AC input to provide a variable high frequency AC output. The planar transformer consists of magnetic core and coils that are arranged in parallel planes. The cores and coils of planar transformer are fabricated from laminated materials and integrated into printed circuit board to offers compactness in size. The parallel and planar arrangement of cores and coils in transformer offers larger surface area for heat dissipation and reduces the magnetic flux paths. The reduction in magnetic flux paths reduces magnetic flux losses in the transformer. As such the planar transformers efficiently operates at high frequencies ranging up to 1 MHz and with high power density. The high frequency AC input supply to the primary coil of the transformer results in a varying dynamic magnetic flux across the core of the transformer that induces the variable high frequency AC output at the output/secondary coil of the transformer. The amount of induction is decided by the number of turns of the coil of the transformer on the primary and secondary side of the transformer. The high frequency AC output of the high frequency planar transformer is determined by the high frequency AC input to the high frequency planar transformer since the number of turns of the coils of transformer are fixed.
As used herein, the term “high frequency AC-DC converter” used herein refers to the component that converts the high frequency AC output into a DC voltage of low magnitude ranging from 40 V to 120V. The DC voltage charges the power pack of the electric vehicle. The high frequency AC-DC converter used herein, converts the variable AC voltage of higher frequency received from the high frequency planar transformer into a DC voltage. The high-frequency AC output is rectified into DC voltage via a bridge rectifier. The bridge rectifier includes switches that includes insulated gate bipolar transistors (IGBTs) and MOSFETs. During the positive half-cycle of the AC input the bridge rectifier passes the current to pass through first pair of switches in parallel and blocks the AC current through remaining second pair of switches in parallel. During the negative half-cycle of the AC input, the bridge rectifier passes the AC current to pass through second pair of transistors and blocks the AC current through first pair of transistors. The alternate passing and blocking of the AC current i.e. rectification generates DC voltage at the output of high frequency AC-DC converter.
As used herein, the term “hybrid network” refers to a circuit provided in DC-DC converter to connect the high frequency DC-AC converter, high frequency planar transformer and high frequency AC-DC converter in series.
As used herein, the term “control unit” refers to the component used herein, in the charger to control the operation of the active front-end AC-DC converter and the DC-DC converter. The control unit is a computational element that is operable to respond to and process instructions that control the system. Optionally, the control unit includes a microprocessor and a micro-controller, a complex instruction set computing (CISC) microprocessor, a reduced instruction set (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a digital signal processor, or any other type of processing unit. In active front-end AC-DC converter, the control unit controls the timing and magnitude of the AC input in the inductor to variably shape the waveform of AC input. The control unit controls the timing and duration of the switching of the switches of the rectification bridge to control the DC link voltage at output of the rectification bridge. The control unit operates based on instructions stored in the memory to process the signal corresponding to power ratings of power pack, executes algorithms, and produces output signals to regulate the switching frequency and duty cycle of switching of the state of switches of the high frequency DC-AC converter. In the DC-DC converter the control unit controls either a duty cycle through pulse width modulation or a switching frequency of the switches of the high frequency DC-AC converter to regulates the voltage gain at the output of the DC-DC converter. The regulation in the voltage gain controls the DC voltage that suitably charges the power pack.
As used herein, the term “switching legs” refers to the circuit provided in the high frequency DC-AC converter to provide the bridge connection that includes a pair of switches. The switches of each switching leg is in series and the switching legs are in parallel with one another.
As used herein, the term “switches” or “switch” or “pair of switches” of the switching legs refers to power electronics devices that control the flow of electrical current. The switches used herein in the high frequency DC-AC converter are wide bandgap switches that are made up of wide band gap (WBG) materials like Silicon Carbide (SiC), Gallium Nitride (GaN). The wide bandgap materials have higher bandgap energy that increases the electron mobility and thereby enables faster rate of switching. The faster rate of switching of WBG switches reduces the time spent in the high-power dissipation state and consequently lowers the switching losses The switches may comprise MOSFETs, IGBTs, transistors, or a combination thereof.
As used herein, the term “second DC link capacitor” refers to the capacitor installed in between the high frequency AC-DC converter and the power pack to minimize voltage ripple from the DC voltage that is received from the high frequency AC-DC converter. The second DC link capacitor enables transfer of the smooth DC voltage to enter the power pack by storing electrical energy during higher amplitudes of DC voltage that is being supplied to the power pack. The second DC link capacitor during lower amplitudes of DC voltage supply, supplies electrical energy.
As used herein, the term “communicably coupled” refers to a bi-directional connection between the various components of the system. The bi-directional connection between the various components of the system enables exchange of data between two or more components of the system. Similarly, bi-directional connection between the system and other elements/modules enables exchange of data between system and the other elements/modules.
As used herein, the term “communication module” relates to an arrangement of interconnected programmable and/or non-programmable components that are configured to facilitate data communication between one or more electronic devices and/or databases, whether available or known at the time of filing or as later developed. The communication module may establish communication between different components of the system via Controller Area Network (CAN), and/or LIN, and/or Zigbee, and/or MOST and so forth. Furthermore, the communication module may utilise, but is not limited to, a public network such as the global computer network known as the Internet, a private network, Wi-Fi, a cellular network including 2G, 3G, 4G, 5G LTE etc. and any other communication system or systems at one or more locations. Additionally, the communication unit may utilise wired or wireless communication that can be carried out via any number of known protocols, including, but not limited to, Internet Protocol (IP), Wireless Access Protocol (WAP), Frame Relay, or Asynchronous Transfer Mode (ATM). Moreover, any other suitable protocols using voice, video, data, or combinations thereof, can also be employed. Moreover, although the communication unit described herein as being implemented with TCP/IP communications protocols, the communication unit may also be implemented using IPX, Appletalk, IP-6, NetBIOS, OSI, any tunnelling protocol (e.g., IPsec, SSH), or any number of existing or future protocols. It would be appreciated that internal components of the home inverter would utilise communication methods including Controller Area Network, Local Interconnect Network, FlexRay, Ethernet, Modbus, Profibus, DeviceNet, Ethernet/IP, Modbus TCP/IP, Profinet and so forth, via the communication unit. Similarly, it would be appreciated that the home inverter would utilise communication methods including Wi-Fi, cellular network, Bluetooth for communication with external modules/units/components, via the communication unit.
As used herein, the term “resonant tank” used herein, refers to the electronic circuit that causes resonance to manipulate the AC voltage output. The resonant tank provides zero voltage and current switching to minimize the switching losses and thereby improves efficiency during manipulation of the magnitude of AC voltage that is suitable to produce the DC voltage. The resonator tank stores electrical energy in the inductor and transferred to the capacitor during supply of AC voltage and consequently releases stored energy from the capacitor to the inductor and to offer zero voltage and current switching for manipulation of AC voltage. The resonant nature of the tank allows the efficient variation of the AC voltage that is suitable to produce desired DC voltage.
As used herein, the term “inductor” refers to a component used in resonant tank to collaborate with capacitive element to create a resonant system. In the resonant tank, the inductor controls the rate of transfer of electrical energy to shape the AC voltage waveform. The shaping of the AC voltage waveform may provide zero voltage switching (ZVS) and zero current switching.
As used herein, the term “capacitor” refers to a component included in resonant tank to to collaborate with inductor to create a resonant system. The capacitor controls the rate of transfer of electrical energy to shape the AC voltage waveform. The shaping of the AC voltage waveform may provide zero voltage switching (ZVS) and zero current switching.
As used herein, the term “enclosure” refers to a mechanical enclosing component of the portable device. The enclosure may be made up of thermally conducting materials. The enclosure may be made up of thermally conducting and electrically insulating materials. The enclosure may be configured in physical contact with the components of the system to enable conduction of heat generated by the components to the enclosure.
As used herein, the term “heat sink” refers to a component configured to dissipate heat generated by the electronics of the portable device.
As used herein, the term “potting compound” refers to semi-solid or foam like compound that prevents components of the portable device from external environmental factors. Beneficially, the potting compound of the enclosure provides structural support and prevent any damage to the components of the portable device occurring due to vibrations and physical impact. The potting compound may include at least one of epoxy, polyurethane, silicone and so on.
Figure 1, in accordance with an embodiment, describes a portable device 100 for charging an electric vehicle. The portable device 100 comprises a connector hub 10 configured to electrically connect the electric vehicle with a power source, a power conversion module 20 configured to convert AC input received from the power source, a residual current detection unit 30, and an enclosure 40 comprising potting compound configured to enclose the power conversion module 20 and residual current detection unit 30. The power conversion module 20 comprises an active front-end AC-DC converter 102, a DC-DC converter 104 and a control unit 112. The DC-DC converter 104 comprises a hybrid network configured within the DC-DC converter 104. The DC-DC converter 104 comprises a high frequency DC-AC converter 106, a high frequency planar transformer 108 and a high frequency AC-DC converter 110. The control unit 112 is configured to control operation of the active front-end AC-DC converter 102 and the DC-DC converter 104. The residual current detection unit 30 communicably coupled with the control unit 112.
The portable device 100 as disclosed in the present disclosure is advantageous in terms of providing fast charging of the power pack with increased efficiency. Beneficially, the portable device 100 of the present disclosure operates at high frequency with reduced losses. Furthermore, the portable device 100 as disclosed in the present disclosure is advantageous in terms of delivering higher amount of power to charge the power pack of the electric vehicle without increasing the size of the components, thus, without increased size and/or volume of the portable device 100. Furthermore, the portable device 100 of the present disclosure is advantageous in terms of generated lesser amount of heat and better thermal management. Furthermore, the portable device 100 of the present disclosure is advantageous in terms of reducing charging time of the power pack of the electric vehicle. Moreover, the portable device 100 of the present disclosure is beneficially bi-directional, thus, enables vehicle to vehicle charging. Beneficially, the synergy of the novel combination of the components of the portable device 100 enables efficient operation of the portable device 100 with improved thermal management. Beneficially, the portable device 100 requires smaller size capacitors for efficient and safe operation.
In an embodiment, the connector hub 10 comprises a first connector 12 and to connect the portable device 100 with the power source and a second connector 14 to connect the portable device with the electric vehicle. Beneficially, the first connector 12 is compatible with at least one 15A domestic power outlet or any other domestic power outlet. In an embodiment, the first connector 12 is plugged in the domestic power outlet. Alternatively, the first connector 12 is extended via a cable to reach the domestic power outlet. Beneficially, the second connector 14 is compatible with a charging port of the electric vehicle. In an embodiment, the second connector 14 is plugged in the charging port of the electric vehicle. Alternatively, the second connector 14 is extended via a charging cable to reach the charging port of the electric vehicle.
In an embodiment, the active front-end AC-DC converter 102 comprises a rectification bridge 102a configured to convert AC input received from a power source into DC voltage for the DC-DC converter 104. Beneficially, the rectification bridge 102a rectifies the AC input to generate the DC link voltage. It is to be understood that the switching of the state of switches is controlled to rectify the AC input voltage.
In an embodiment, the active front-end AC-DC converter 102 comprises an inductor 102b for power factor correction of the AC input received from the power source. It is to be understood that the inductor 102b present in the active front-end AC-DC converter 102 actively shape the AC input waveform. Beneficially, the shaping of the AC input current waveform eliminates the phase shift between the waveform of the AC input current and AC input voltage thereby, reduces losses.
In an embodiment, the portable device 100 comprises a first DC link capacitor 114 installed between the active front-end AC-DC converter 102 and the high frequency DC-AC converter 106 to minimize voltage ripple between the active front-end AC-DC converter 102 and high frequency DC-AC converter 106. It is to be understood that the first DC link capacitor 114 absorbs electrical energy of the DC link voltage during higher amplitudes of the DC link voltage and releases energy during the lower amplitudes of the DC link voltage. Beneficially, the first DC link capacitor 114 alternately stores and releases the electrical energy to minimize the voltage ripple from DC link voltage. Beneficially, the lowered voltage ripples result in lesser losses during the operation of the portable device 100. Such lowered losses may improve thermal management of the portable device 100.
In an embodiment, the high frequency DC-AC converter 106 comprises at least two switching legs 116a, 116b configured in a bridge configuration. Each of the switching leg 116a, 116b comprises a pair of switches S1, S2 wherein the control unit 112 is configured to control switching sequence of the pair of switches S1, S2 of each of the switching leg 116a, 116b. It is to be understood that the bridge configuration includes switching legs 116a, 116b that enables conversion of the DC link voltage into AC voltage of higher frequency. The switching of the state of switches S1, S2 is carried out in a predefined switching sequence i.e switch S1 of switching leg 116a and switch S2 of another switching leg 116b are in on state in first step and remaining switches S2, S1 are in on state in next step. Beneficially, the alternate switching of the states of the switches S1, S2 of switching legs 116a, 116b in the predefined switching sequence converts the DC link voltage into AC link voltage of high frequency at the output of the high frequency DC-AC converter 106. The duty cycle and the switching frequency of the state of switches S1, S2 determines the frequency and the amplitude of the AC voltage.
In an embodiment, each of the switch S1, S2 is a wide band gap switch. Beneficially, the wide band gap switch enables the switches to operate efficiently at high switching frequencies within high frequency DC-AC converter 106. It is to be understood that the wide band gap switch may comprise material such as Silicon Carbide (SiC) and Gallium Nitride (GaN). Beneficially, the wide band gap switches produce low switching loss at high switching frequencies. Beneficially, the wide band gap switches may enable the portable device 100 to operate at frequency up to 1 MHz.
In an embodiment, the pair of switches S1, S2 of the high frequency DC-AC converter 106, when in operation, convert the DC voltage received from the active front-end AC-DC converter 102 into a high frequency AC input for the high frequency planar transformer 108. It is to be understood that the high frequency DC-AC converter 106 conducts the DC current after application of DC link voltage, by switching on a pair of switches S1, S2 of switching legs 116a, 116b respectively during first step and conducts the DC current by switching on another pair of switches S2, S1 of switching legs 116a, 116b respectively during second step. Beneficially, the alternate switching of state of pair of switches S1, S2 generates the high frequency AC input for the high frequency planar transformer 108.
In an embodiment, the high frequency planar transformer 108 steps up or steps down the received high frequency AC input to provide a variable high frequency AC output. It is to be understood that the high frequency planar transformer 108 efficiently steps up or steps down high frequency AC input received from the high frequency DC-AC converter 106, with low switching loss and better heat dissipation, to provide a variable high-frequency AC output voltage. It is to be understood that the high frequency planar transformer 108 enable minimal thermal losses and efficient thermal management in the portable device 100.
In an embodiment, the high frequency AC-DC converter 110 converts the variable high frequency AC output received from the high frequency planar transformer 108 into a DC voltage to charge at least one power pack of the electric vehicle. It is to be understood that the high frequency AC-DC converter 110 rectifies the high-frequency AC output into DC voltage. Beneficially, the timing and the duration of the state of switching in the rectification regulates the DC voltage at the output of the high frequency AC-DC converter 110 that is suitable to charge the power pack of the electric vehicle. Beneficially, the high frequency AC-DC converter 110 is controlled by the control unit 112 to regulate the DC voltage to charge the at least one power pack of the electric vehicle.
In an embodiment, the portable device 100 comprises a second DC link capacitor 118 installed between the high frequency AC-DC converter 110 and the at least one power pack to minimize voltage ripple between the high frequency AC-DC converter 110 and the at least one power pack. It is to be understood that the second DC link capacitor 118 absorbs electrical energy of the DC voltage during higher amplitudes of the DC voltage and releases energy during the lower amplitudes of the DC voltage. Beneficially, the second DC link capacitor 118 alternately stores and releases the electrical energy to minimize the voltage ripple from DC voltage. Beneficially, the lowered voltage ripples result in a smooth DC voltage delivered to charge the at least one power pack of the electric vehicle. The charging of the at least one power pack of the electric vehicle with such smooth DC voltage may improve operational life of the at least one power pack of the electric vehicle.
In an embodiment, the control unit 112 comprises a communication module 122 to communicably couple the portable device with the at least one power pack of the electric vehicle, wherein the communication module 122 is configured to receive at least one parameter associated with the at least one power pack from a battery management system of the at least one power pack of the electric vehicle. It is to be understood that the communication module 122 uses the communication protocol to transfer the data of the parameter from the battery management system of the power pack to the control unit 112. Beneficially, the control unit 112 communicates with the battery management system of the power pack via the communication module 122.
In an alternative embodiment, the portable device 100 comprises the communication module 122, wherein the communication module 122 is communicably coupled with the control unit 112 and the battery management system of the at least one power pack of the electric vehicle. Optionally, the communication module 122 is configured to receive at least one parameter associated with the at least one power pack from a battery management system of the at least one power pack. Optionally, the communication module 122 is configured to provide the received at least one parameter associated with the at least one power pack to the control unit 112. Optionally, the communication module 122 may be communicably coupled with a server arrangement to enable data exchange between the portable device 100 and the server arrangement.
In an embodiment, the control unit 112 is configured to control operation of the active front-end AC-DC converter 102, the high frequency DC-AC converter 106, the high frequency planar transformer 108, and the high frequency AC-DC converter 110 based on the at least one parameter associated with the at least one power pack, to regulate the DC voltage provided to charge the at least one power pack. It is to be understood that on the basis of parameters associated with the power pack, the control unit 112 controls the timing and magnitude of the AC input in the inductor 102b and the timing and duration of the switching of the switches of the rectification bridge 102a of the active front-end AC-DC converter 102. The control unit 112 controls the switching frequency/ duty cycle of the high frequency DC-AC converter 106 to regulate the DC voltage at the output of the DC-DC converter 104. The control unit 112 controls the timing and duration of the switching of the switches of the high frequency AC-DC converter 110 to regulate the DC voltage for charging the at least one power pack of the electric vehicle.
In an embodiment, the at least one parameter associated with the at least one power pack comprises a voltage requirement of the at least one power pack and a current requirement of the at least one power pack. Beneficially, the DC voltage output of the portable device 100 may be adjusted in real time based on the at least one parameter associated with the at least one power pack.
In an embodiment, the control unit 112 controls a duty cycle of the switches S1, S2 to regulate the DC voltage provided to charge the at least one power pack. It is to be understood that the duty cycle determines the voltage at the input of the high frequency planar transformer 108 and thereby determines the DC voltage output to charge the at least one power pack. Beneficially, the duty cycle control enables efficient operation of the portable device 100 for charging the at least one power pack of the electric vehicle.
In an embodiment, the residual current detection unit 30 is configured to detect a residual current in the portable device 100 and communicate with the control unit 112 to stop the operation of the power conversion module 20, when the residual current is detected in the portable device 100. Beneficially, the residual current detection unit 30 prevents the user from getting the electrical shock in case of fault (leakage current).
In an embodiment, the enclosure 40 comprises a heat sink 42 configured in surface contact with components of the power conversion module 20 for thermal management in the portable device 100. It is to be understood that the physical contact of the heat sink 42 with the active front-end AC-DC converter 102 and the DC-DC converter 104 improves thermal management in the portable device 100 as the heat generated by the active front-end AC-DC converter 102 and the DC-DC converter 104 during the operation of the portable device 100 is efficiently conducted outside the enclosure 40. Beneficially, the physical contact transfers the maximum amount of heat generated in the active front-end AC-DC converter 102 and the DC-DC converter 104, to the external environment. Furthermore, it is to be understood that due to the physical aspects and design of the high frequency planar transformer 108 in the DC-DC converter 104, the physical contact between the DC-DC converter 104 and the enclosure 40 is enabled leading to better heat transfer from the DC-DC converter 104 to the external environment.
In an embodiment, the wherein the enclosure 40 comprises at least one provision for extension of cables from the first connector 12 and the second connector 14. Beneficially, the at least one provision for extension of cables allows extension of cables from the first connector 12 and the second connector 14.
In an embodiment, the enclosure 40 is configured to provide ingress protection to the connector hub 10, the power conversion module 20, and the residual current detection unit 30. Beneficially, the enclosure 40 prevents any external material from entering into the portable device 100.
Figure 2, in accordance with an embodiment, describes a circuit diagram of the portable device 100 for an electric vehicle. The portable device 100 comprises a connector hub 10 configured to electrically connect the electric vehicle with a power source, a power conversion module 20 configured to convert AC input received from the power source, a residual current detection unit 30, and an enclosure 40 comprising potting compound configured to enclose the power conversion module 20 and residual current detection unit 30. The power conversion module 20 comprises an active front-end AC-DC converter 102, a DC-DC converter 104 and a control unit 112. The DC-DC converter 104 comprises a hybrid network configured within the DC-DC converter 104. The DC-DC converter 104 comprises a high frequency DC-AC converter 106, a high frequency planar transformer 108 and a high frequency AC-DC converter 110. The control unit 112 is configured to control operation of the active front-end AC-DC converter 102 and the DC-DC converter 104. The residual current detection unit 30 communicably coupled with the control unit 112. Furthermore, the active front-end AC-DC converter 102 comprises a rectification bridge 102a configured to convert AC input received from a power source into DC voltage for the DC-DC converter 104. Furthermore, the active front-end AC-DC converter 102 comprises an inductor 102b for power factor correction of the AC input received from the power source. Furthermore, the portable device 100 comprises a first DC link capacitor 114 installed between the active front-end AC-DC converter 102 and the high frequency DC-AC converter 106 to minimize voltage ripple between the active front-end AC-DC converter 102 and high frequency DC-AC converter 106. Furthermore, the high frequency DC-AC converter 106 comprises at least two switching legs 116a, 116b configured in a bridge configuration. Each of the switching leg 116a, 116b comprises a pair of switches S1, S2 wherein the control unit 112 is configured to control switching sequence of the pair of switches S1, S2 of each of the switching leg 116a, 116b. Furthermore, each of the switch S1, S2 is a wide band gap switch. Furthermore, the pair of switches S1, S2 of the high frequency DC-AC converter 106, when in operation, convert the DC voltage received from the active front-end AC-DC converter 102 into a high frequency AC input for the high frequency planar transformer 108. Furthermore, the high frequency planar transformer 108 steps up or steps down the received high frequency AC input to provide a variable high frequency AC output. Furthermore, the high frequency AC-DC converter 110 converts the variable high frequency AC output received from the high frequency planar transformer 108 into a DC voltage to charge at least one power pack of the electric vehicle. Furthermore, the portable device 100 comprises a second DC link capacitor 118 installed between the high frequency AC-DC converter 110 and the at least one power pack to minimize voltage ripple between the high frequency AC-DC converter 110 and the at least one power pack. Furthermore, the control unit 112 is configured to control operation of the active front-end AC-DC converter 102, the high frequency DC-AC converter 106, the high frequency planar transformer 108, and the high frequency AC-DC converter 110 based on the at least one parameter associated with the at least one power pack, to regulate the DC voltage provided to charge the at least one power pack. Furthermore, the control unit 112 controls a duty cycle of the switches S1, S2 to regulate the DC voltage provided to charge the at least one power pack.
Figure 3, in accordance with another embodiment, describes the portable device 100 for the electric vehicle with resonant tank 120. The power conversion module 20 of the portable device 100 comprises the active front-end AC-DC converter 102, the DC-DC converter 104 and the control unit 112. The DC-DC converter 104 comprises the hybrid network configured within the DC-DC converter 104. The DC-DC converter 104 comprises the high frequency DC-AC converter 106, the high frequency planar transformer 108 and the high frequency AC-DC converter 110. The control unit 112 is configured to control operation of the active front-end AC-DC converter 102 and the DC-DC converter 104.
In an embodiment, the DC-DC converter 104 comprises a resonant tank 120, wherein at least one inductor 120a and at least one capacitor 120b of the resonant tank 120 are in resonance. Beneficially, the resonant tank 120 provides zero voltage and current switching to minimize the switching losses and thereby improves efficiency during manipulation of the magnitude of AC link voltage of high frequency. It is to be understood that the resonant nature of the DC-DC converter 104 allows the efficient variation of the AC link voltage that is suitable to produce DC voltage that charges the power pack.
In an embodiment, the control unit 112 controls a switching frequency of the switches S1, S2 to regulate the DC voltage provided to charge the at least one power pack. It is to be understood that the switching frequency of the switches S1, S2 regulates the voltage gain at the output of the DC-DC converter 104 and thereby controls the DC voltage output to charge the at least one power pack.
In an embodiment, the DC-DC converter 104 acts as a resonant DC-DC converter 104 due to the resonant tank 120 and provides the regulated DC voltage to charge the at least one power pack. Beneficially, the resonant tank 120 regulates the voltage gain at the output of the DC-DC converter 104 and thereby regulates the DC voltage to charge the at least one power pack.
Figure 4, in accordance with another embodiment, describes a circuit diagram of the portable device 100 for the electric vehicle with resonant tank 120. The portable device 100 comprises a connector hub 10 configured to electrically connect the electric vehicle with a power source, a power conversion module 20 configured to convert AC input received from the power source, a residual current detection unit 30, and an enclosure 40 comprising potting compound configured to enclose the power conversion module 20 and residual current detection unit 30. The power conversion module 20 comprises an active front-end AC-DC converter 102, a DC-DC converter 104 and a control unit 112. The DC-DC converter 104 comprises a hybrid network configured within the DC-DC converter 104. The DC-DC converter 104 comprises a high frequency DC-AC converter 106, a high frequency planar transformer 108 and a high frequency AC-DC converter 110. The control unit 112 is configured to control operation of the active front-end AC-DC converter 102 and the DC-DC converter 104. The residual current detection unit 30 communicably coupled with the control unit 112. Furthermore, the active front-end AC-DC converter 102 comprises a rectification bridge 102a configured to convert AC input received from a power source into DC voltage for the DC-DC converter 104. Furthermore, the active front-end AC-DC converter 102 comprises an inductor 102b for power factor correction of the AC input received from the power source. Furthermore, the portable device 100 comprises a first DC link capacitor 114 installed between the active front-end AC-DC converter 102 and the high frequency DC-AC converter 106 to minimize voltage ripple between the active front-end AC-DC converter 102 and high frequency DC-AC converter 106. Furthermore, the high frequency DC-AC converter 106 comprises at least two switching legs 116a, 116b configured in a bridge configuration. Each of the switching leg 116a, 116b comprises a pair of switches S1, S2 wherein the control unit 112 is configured to control switching sequence of the pair of switches S1, S2 of each of the switching leg 116a, 116b. Furthermore, each of the switch S1, S2 is a wide band gap switch. Furthermore, the pair of switches S1, S2 of the high frequency DC-AC converter 106, when in operation, convert the DC voltage received from the active front-end AC-DC converter 102 into a high frequency AC input for the high frequency planar transformer 108. Furthermore, the high frequency planar transformer 108 steps up or steps down the received high frequency AC input to provide a variable high frequency AC output. Furthermore, the high frequency AC-DC converter 110 converts the variable high frequency AC output received from the high frequency planar transformer 108 into a DC voltage to charge at least one power pack of the electric vehicle. Furthermore, the portable device 100 comprises a second DC link capacitor 118 installed between the high frequency AC-DC converter 110 and the at least one power pack to minimize voltage ripple between the high frequency AC-DC converter 110 and the at least one power pack. Furthermore, the control unit 112 is configured to control operation of the active front-end AC-DC converter 102, the high frequency DC-AC converter 106, the high frequency planar transformer 108, and the high frequency AC-DC converter 110 based on the at least one parameter associated with the at least one power pack, to regulate the DC voltage provided to charge the at least one power pack. Furthermore, the DC-DC converter 104 comprises a resonant tank 120, wherein at least one inductor 120a and at least one capacitor 120b of the resonant tank 120 are in resonance. Furthermore, the control unit 112 controls a switching frequency of the switches S1, S2 to regulate the DC voltage provided to charge the at least one power pack. Furthermore, the DC-DC converter 104 acts as a resonant DC-DC converter 104 due to the resonant tank 120 and provides the regulated DC voltage to charge the at least one power pack.
In the description of the present invention, it is also to be noted that, unless otherwise explicitly specified or limited, the terms “disposed,” “mounted,” and “connected” are to be construed broadly, and may for example be fixedly connected, detachably connected, or integrally connected, either mechanically or electrically. They may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Modifications to embodiments and combinations of different embodiments of the present disclosure described in the foregoing are possible without departing from the scope of the present disclosure as defined by the accompanying claims. Expressions such as “including”, “comprising”, “incorporating”, “have”, and “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural where appropriate.
Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the present disclosure, the drawings, and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.
,CLAIMS:We Claim:
1. A portable device (100) for charging an electric vehicle, wherein the portable device (100) comprises:
- a connector hub (10) configured to electrically connect the electric vehicle with a power source;
- a power conversion module (20) configured to convert AC input received from the power source, wherein the power conversion module (20) comprises:
- an active front-end AC-DC converter (102);
- a DC-DC converter (104) comprising a hybrid network configured within the DC-DC converter (104), wherein the DC-DC converter (104) comprises:
- a high frequency DC-AC converter (106);
- a high frequency planar transformer (108); and
- a high frequency AC-DC converter (110); and
- a control unit (112) configured to control operation of the active front-end AC-DC converter (102) and the DC-DC converter (104);
- a residual current detection unit (30) communicably coupled with the control unit (112); and
- an enclosure (40) comprising potting compound configured to enclose the power conversion module (20) and residual current detection unit (30).
2. The portable device (100) as claimed in claim 1, wherein the connector hub (10) comprises a first connector (12) and to connect the portable device (100) with the power source and a second connector (14) to connect the portable device with the electric vehicle.
3. The portable device (100) as claimed in claim 1, wherein the active front-end AC-DC converter (102) comprises a rectification bridge (102a) configured to convert AC input received from the power source into DC voltage for the DC-DC converter (104) and an inductor (102b) for power factor correction of the AC input received from the power source.
4. The portable device (100) as claimed in claim 1, wherein the portable device (100) comprises a first DC link capacitor (114) installed between the active front-end AC-DC converter (102) and the high frequency DC-AC converter (106) to minimize voltage ripple between the active front-end AC-DC converter (102) and high frequency DC-AC converter (106).
5. The portable device (100) as claimed in claim 1, wherein the high frequency DC-AC converter (106) comprises at least two switching legs (116a, 116b) configured in a bridge configuration, wherein each of the switching leg (116a, 116b) comprises a pair of switches (S1, S2), and wherein the control unit (112) is configured to control switching sequence of the pair of switches (S1, S2) of each of the switching leg (116a, 116b).
6. The portable device (100) as claimed in claim 5, wherein each of the switch (S1, S2) is a wide band gap switch.
7. The portable device (100) as claimed in claim 1, wherein the pair of switches (S1, S2) of the high frequency DC-AC converter (106), when in operation, convert the DC voltage received from the active front-end AC-DC converter (102) into a high frequency AC input for the high frequency planar transformer (108).
8. The portable device (100) as claimed in claim 1, wherein the high frequency planar transformer (108) steps up or steps down the received high frequency AC input to provide a variable high frequency AC output.
9. The portable device (100) as claimed in claim 1, wherein the high frequency AC-DC converter (110) converts the variable high frequency AC output received from the high frequency planar transformer (108) into a DC voltage to charge at least one power pack of the electric vehicle.
10. The portable device (100) as claimed in claim 1, wherein the portable device (100) comprises a second DC link capacitor (118) installed between the high frequency AC-DC converter (110) and the at least one power pack to minimize voltage ripple between the high frequency AC-DC converter (110) and the at least one power pack of the electric vehicle.
11. The portable device (100) as claimed in claim 1, wherein the control unit (112) comprises a communication module (122) to communicably couple the portable device with the at least one power pack of the electric vehicle, wherein the communication module (122) is configured to receive at least one parameter associated with the at least one power pack from a battery management system of the at least one power pack of the electric vehicle.
12. The portable device (100) as claimed in claim 11, wherein the control unit (112) is configured to control operation of the active front-end AC-DC converter (102), the high frequency DC-AC converter (106), the high frequency planar transformer (108), and the high frequency AC-DC converter (110) based on the received at least one parameter associated with the at least one power pack, to regulate the DC voltage provided to charge the at least one power pack.
13. The portable device (100) as claimed in claim 12, wherein the control unit (112) controls a duty cycle of the switches (S1, S2) to regulate the DC voltage provided to charge the at least one power pack.
14. The portable device (100) as claimed in claim 1, wherein the DC-DC converter (104) comprises a resonant tank (120), wherein at least one inductor (120a) and at least one capacitor (120b) of the resonant tank (120) are in resonance.
15. The portable device (100) as claimed in claim 14, wherein the control unit (112) controls a switching frequency of the switches (S1, S2) to regulate the DC voltage provided to charge the at least one power pack.
16. The portable device (100) as claimed in claim 15, wherein the DC-DC converter (104) acts as a resonant DC-DC converter (104) due to the resonant tank (120) and provides the regulated DC voltage to charge the at least one power pack.
17. The portable device (100) as claimed in claim 1, wherein the residual current detection unit (30) is configured to detect a residual current in the portable device (100) and communicate with the control unit (112) to stop the operation of the power conversion module (20), when the residual current is detected in the portable device (100).
18. The portable device (100) as claimed in claim 1, wherein the enclosure (40) comprises a heat sink (42) configured in surface contact with components of the power conversion module (20) for thermal management in the portable device (100).
19. The portable device (100) as claimed in claim 1, wherein the enclosure (40) comprises at least one provision for extension of cables from the first connector (12) and the second connector (14).
20. The portable device (100) as claimed in claim 1, wherein the enclosure (40) is configured to provide ingress protection to the connector hub (10), the power conversion module (20), and the residual current detection unit (30).