DESC:WIRELESS CHARGING ECOSYSTEM FOR SWAPPABLE POWERPACK
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority from Indian Provisional Patent Application No. 202321012850 filed on 25/02/2023, the entirety of which is incorporated herein by a reference.
TECHNICAL FIELD
The present disclosure generally relates to charging of swappable power packs. Particularly, the present disclosure relates to a charging ecosystem for swappable power packs.
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 powered from a power pack that drives the high voltage components such as motor and the low voltage components such as headlights, lamps of the vehicle. The power pack operating in the vehicle is electrically charged at desired time intervals after certain discharge or full discharge. The electrical vehicle consumes large time during charging of the power pack from residential outlets that increases the down time of the vehicle.
The alternative way of powering the electrical vehicle is to refuel the energy source of EVs by mechanically swapping the power pack of electric vehicle after discharging, with a power pack of similar ratings that is referred to as swappable power pack. The swappable power pack are typically fully charged batteries. The depleted batteries are again charged to full capacity and made available for swapping. The swappable power pack offers advantages such as refueling the vehicle in a shorter time and charging of the discharged power packs at user desired time intervals. The swapping provides a faster and more user-friendly approach to extend the driving range of EVs by eliminating the need for time-consuming charging sessions. This approach enhances the overall flexibility and practicality of electric vehicle ownership, making EVs more accessible and appealing to a broader range of consumers.
Conventionally, the swappable power packs for electric vehicles are charged through plugin wired connection through a power source either residential outlet or commercial battery swapping stations. However, during plug in wired charging of swappable power packs, the physical connection between the swappable power packs and the charging cable is required for charging at regular time intervals that causes and increases the wear and tear of the power pack due to frequent plugging and unplugging of the cables from the connectors and even damages the connectors of the power pack. Moreover, the connectors of the power pack are exposed to environment that causes corrosion and other damages to the exposed connectors. The increase in wear and tear and corrosion reduces the life of the swappable power pack. During plugin wired charging of the power packs, the exposure of connectors causes harms to the human life as a result of the spark, electric shocks or bursts of power packs.
An alternative solution to the plugin wired charging of the electric vehicle is wireless charging of the electric vehicle. With recent developments in the area of wireless charging of electric vehicles, the electric vehicle is parked over a wireless charging system and the power transferred wirelessly to the power pack of the electric vehicle to charge the power pack of the electric vehicle. However, such systems suffer from multiple problems. There is a considerable amount of distance between the transmitter coil and the receiver coil based on the ground clearance of the vehicle. The larger distance poses difficulty in alignment of the coils and thereby increases the electric energy losses during transmission of electric power. For improving the alignment between the coils, in wireless charging systems, the number of coils are increased in the transmitter coil. However, the increase in number of coils increases the unutilized magnetic field and thereby further widens the power transfer losses. In addition, the onboard charging apparatus of typical wireless charger is heavy due to larger weight and volume occupancy in the vehicle and thereby, demands high electrical power and reduces the performance of the power packs.
Therefore, there exists a need for an improved charging ecosystem for electric vehicles.
SUMMARY
An object of the present disclosure is to provide a system for wireless charging of at least one swappable power pack.
In accordance with an aspect of the present disclosure, there is provided a system for wireless charging of at least one swappable power pack. The system comprises a home inverter cum swappable battery charging station and the at least one swappable power pack. The home inverter cum swappable battery charging station comprises a first magnetic coil. The swappable power pack comprises a second magnetic coil. The first magnetic coil and the second magnetic coil form a high-frequency air core transformer to enable transfer of electrical energy between the home inverter and the at least one swappable power pack.
The present disclosure provides system for wireless charging of at least one swappable power pack. The system for wireless charging of at least one swappable power pack as disclosed in the present disclosure is advantageous in terms of providing mechanical connector-less charging to the swappable power packs. Beneficially, the connector-less charging of the swappable power packs reduces mechanical wear and tear of the swappable power packs over time, thus, may increase operational life of the swappable power pack. The system as disclosed in the present disclosure is advantageous in terms of improved charging efficiency as airgap between the magnetic coils is negligible. Furthermore, the system of the present disclosure is advantageous in terms of ensuring proper alignment between the magnetic coils for efficient power transfer. Moreover, the system of the present disclosure is advantageous in terms of eliminating open electrical connectors and/or contactors improving human safety around the system while the system is operational. Moreover, the system of the present disclosure is advantageous in terms of enabling power backup from the swappable power packs due to the bi-directional nature of the system.
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 system for wireless charging of at least one swappable power pack, in accordance with an embodiment of the present disclosure.
FIG. 2 illustrates a circuit diagram of a system for wireless charging of at least one swappable power pack, in accordance with an 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 a system for wireless charging of at least one swappable power pack 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 term “swappable power pack” refers to a fully charged power pack typically, that is designed to replace a power pack operating in the electric vehicle, after the operating power pack is fully discharged or semi-discharged. The swapping of the operating power pack with the swappable power pack refuels the electric vehicle. The swappable power pack may comprise one or more rechargeable battery modules and associated control systems enclosed in a housing. The housing may be configured with standardized dimensions and mechanical interfaces to facilitate integration and disintegration from the electric vehicle.
As used herein, the term “home inverter” or “swappable battery charging station” are used herein interchangeably and refers to a power conversion device that is designed to convert the AC power from the residential outlets into DC power for charging the battery pack and convert the DC power of the charged battery pack into AC power to provide power pack to the residential (domestic loads) during the unavailability of the AC power from grid. The home inverter (swappable battery charging station) may have a fixed battery pack along with swappable battery packs. It may be understood by the person skilled in the art that the swappable battery pack charged by the home inverter (swappable battery charging station) may be used for mobility application.
As used herein, the term “first magnetic coil” refers to the electrical component of the home inverter that converts the electrical energy into a varying magnetic field propagating in the vicinity of the first magnetic coil. The first magnetic coil is used herein, in the home inverter, to receive and carry the high frequency AC input. The high frequency AC input, flows through the first magnetic coil to produce a rapidly varying magnetic field in the vicinity of the first magnetic coil.
As used herein, the term “second magnetic coil” refers to the electrical component of the swappable power pack that receives varying magnetic field from the first magnetic coil for induction of electrical energy therein. The second magnetic coil is magnetically coupled with the first magnetic coil to induce high frequency AC output therein.
As used herein, the term “high-frequency air core transformer” refers to the transformer formed with the first magnetic coil and the second magnetic coil along with air gap therebetween. The high frequency air core transformer magnetically and electrically couples the home inverter and the swappable battery pack enabling wireless power transfer between them. Moreover, the high frequency air core transformer may also step up or step down the power between the home inverter and the swappable battery pack.
As used herein, the term “battery pack compartment” refers to the compartment in the home inverter to accommodate the swappable power pack in a pre-decided location. The battery pack compartment used herein, is included in the home inverter, to receive and secure the swappable power pack. The battery pack compartment includes alignment mechanism/grooves to correctly position the second magnetic coil with respect to the first magnetic coil. The material of the battery pack compartment may include carbon fibre reinforced polymers (CFRP) or glass fibre reinforced polymers (GFRP). Alternatively, the battery pack compartment may be made up of any suitable material.
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 the home inverter, 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 that includes vehicle to line and line 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 shape 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 link 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 “high frequency DC-AC resonant converter” refers to the component that converts DC link voltage into a high frequency AC input for the transformer. The high frequency DC-AC resonant converter used herein in DC-DC converter, receives the DC voltage from the active front end AC-DC converter along with DC link capacitor and converts DC voltage into AC input voltage/current of a high frequency. The high frequency DC-AC resonant converter includes insulated gate bipolar transistors (IGBTs) or metal-oxide-semiconductor field-effect transistors (MOSFETs), as switches. The switching rate of the switching sequence of the pair of switches of the switching legs, determines the amplitude and the frequency of the AC input at the output of the high frequency DC-AC resonant converter. The frequency/rate of the switching may be controlled to stay close to the resonant frequency of the resonant components of the high frequency DC-AC resonant converter, to efficiently convert the DC voltage into high frequency AC input. Such operation of the resonant converter minimizes the switching loss during operation of the high frequency DC-AC resonant converter.
As used herein, the term “switching legs” refers to the circuit provided in the high frequency resonant DC-AC converter for conversion of power either from AC to DC or from DC to AC. Each of the switching leg comprises a pair of switches. The switching legs may be arranged in a bridge configuration. Furthermore, the number of switching legs in the converter may be determined according to the number of phases to be converted.
As used herein, the term “DC link capacitor” refers to the component that stores electrical energy of DC link power, during periods of high voltage or high-power availability to be utilized during periods of lower voltage or low-power. The DC link capacitor used herein in the home inverter, absorbs electrical energy of the DC link voltage while the magnitudes of voltage are high. The DC link capacitor releases electrical energy during the lower magnitudes of the DC link voltage. The alternate storage and release of electrical energy minimizes the voltage ripples from DC link voltage to smooth out the DC link voltage at the output of the first DC link capacitor.
As used herein, the term “control unit” present in the home inverter refers to the component to control the operation of the active front-end AC-DC converter and the high frequency DC-AC resonant converter. The control unit may be a computational element that is operable to respond to and process instructions that controls the components in the system. Optionally, the control unit comprises 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 may operate based on instructions stored in a memory. The control unit may generate control signals to control the operation of the active front end AC-DC converter and the high frequency DC-AC converter.
As used herein, the terms “battery module” refers to multiple individual battery cells that are connected to provide a higher combined voltage or current capacity than what a single battery cell can offer. The battery module is designed to store electrical energy and supply it as needed to various devices or systems. Battery module, as referred herein may be used for various purposes such as power electric vehicles and other energy storage applications.
As used herein, the term “battery management system” refers to an electronic system used herein in the swappable power pack, monitors the plurality of parameters associated with battery modules and manages the charging/discharging of the plurality of battery cells of the battery module. The plurality of parameters may include the voltage and current associated with the battery module. The battery management system manages the operation within the safe current and voltage limits. Furthermore, the battery management system may protect the battery module from damage by preventing overcharging, over-discharging, overheating, and other abnormal conditions. Furthermore, the battery management system may balance the voltage across the individual cells in a battery pack to extend the battery's life and improve its performance. Moreover, the battery management system estimates the battery's state of charge (SoC), state of health (SoH), and remaining capacity.
As used herein, the term “control unit” present in the swappable power pack refers to component to control the operation of a high frequency bi-directional power converter. The control unit present in the swappable power pack may be communicably coupled with the battery management system. The control unit may be a computational element that is operable to respond to and process instructions that controls the components in the system. Optionally, the control unit comprises 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. The control unit may control the switches of the high frequency bi-directional power converter to regulate the DC power output provided to charge the battery module of the swappable power pack.
As used herein, the term “high frequency bi-directional power converter” refers to the component that converts the high frequency AC output into a DC power to charge the battery module or vice versa to provide power backup during unavailability of the AC grid. The high frequency bi-directional power converter used herein, converts the variable AC output of higher frequency received from the second magnetic coil, in the DC voltage ranging from 40 V to 120V. The high-frequency AC output is rectified into the 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 high frequency AC output, the bridge rectifier passes the AC 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 switches and blocks the AC current through first pair of switches. The alternate passing and blocking of the AC current i.e. rectification, generates DC voltage at the output of high frequency bi-directional power converter.
As used herein, the term “phase inverter legs” refers to the circuit provided in the high frequency bi-directional power converter for conversion of power either from AC to DC or from DC to AC. Each of the phase inverter leg comprises a pair of switches. The phase inverter legs may be arranged in a bridge configuration. Furthermore, the number of phase inverter legs in the converter may be determined according to the number of phases to be converted.
As used herein, the term “switches” refers to refers to power electronics devices that control the flow of electrical current. The switches used herein in the rectification bridge, high frequency DC-AC resonant converter and the high frequency bi-directional power converter are wide bandgap switches that are made up of wide band gap materials like SiC, 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 “DC link capacitor” refers to the component present in the swappable power pack, that alternately stores and releases the electrical energy obtained during high and low magnitudes of the DC voltage respectively. The alternate storing and releasing of energy eliminate the ripples from the DC voltage to smooth out the DC voltage output.
As used herein, the term ‘communicably coupled’ refers to a bi-directional connection between the various components of the system that enables the exchange of data between two or more components of the system. The components of the system may communicate with each other via suitable communication protocols.
Figure 1, in accordance with an embodiment, describes a system 100 for wireless charging of at least one swappable power pack 102. The system 100 comprises a home inverter cum swappable battery charging station 104 and the at least one swappable power pack 102. The home inverter cum swappable battery charging station 104 comprises a first magnetic coil 106. The swappable power pack 102 comprises a second magnetic coil 108. The first magnetic coil 106 and the second magnetic coil 108 form a high-frequency air core transformer 110 to enable transfer of electrical energy between the home inverter 104 and the at least one swappable power pack 102.
The system 100 for wireless charging of at least one swappable power pack 102 as disclosed in the present disclosure is advantageous in terms of providing mechanical connector-less charging to the swappable power packs 102. Beneficially, the connector-less charging of the swappable power packs 102 reduces mechanical wear and tear of the swappable power packs 102 over time, thus, may increase operational life of the swappable power pack 102. The system 100 as disclosed in the present disclosure is advantageous in terms of improved charging efficiency as airgap between the magnetic coils 106 and 108 is negligible. Furthermore, the system 100 of the present disclosure is advantageous in terms of ensuring proper alignment between the magnetic coils 106 and 108 for efficient power transfer. Moreover, the system 100 of the present disclosure is advantageous in terms of eliminating open electrical connectors and/or contactors improving human safety around the system 100 while the system 100 is operational. Moreover, the system 100 of the present disclosure is advantageous in terms of enabling power backup from the swappable power packs 102 due to the bi-directional nature of the system 100.
In an embodiment, the home inverter 104 comprises at least one battery pack compartment 112 for receiving and securing the at least one swappable power pack 102. It is to be understood that the battery pack compartment 112 comprises complementary shape to the exposed surface area of second magnetic coil 108. Beneficially, the securing of the swappable power pack 102 in the battery pack compartment 112 provides for the correct positioning of the second magnetic coil 108 at a predefined distance from the first magnetic coil 106.
In an embodiment, the home inverter 104 comprises an active front-end AC-DC converter 114, wherein the active front-end AC-DC converter 114 comprises a rectification bridge 114a configured to convert AC input received from a power source into DC link voltage. Beneficially, the rectification bridge 114a rectifies the AC input to generate the DC link voltage.
In an embodiment, the active front-end AC-DC converter 114 comprises an inductor 114b for power factor correction of the AC input received from the power source. It is to be understood that the inductor 114b is included in the active front-end AC-DC converter 114 to actively shape the waveform of AC input. Beneficially, the shaping of the waveform of the AC input current eliminates the phase shift in the waveform of the AC input thereby, reduces losses.
In an embodiment, the home inverter 104 comprises a high frequency DC-AC resonant converter 116, wherein the high frequency DC-AC resonant converter 116 comprises at least two switching legs 116a, 116b configured in a bridge configuration, and wherein each of the switching leg 116a, 116b comprises a pair of switches S1, S2. It is to be understood that the bridge configuration of switching legs 116a,116b enables conversion of the DC link voltage into AC input 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 input of high frequency at the output of the high frequency DC-AC resonant converter 116. The switching rate of the switching sequence of state of switches S1, S2 determines the frequency of the high frequency AC input. The high frequency DC-AC resonant converter 116 comprises a resonant circuit, wherein the resonant circuit comprises an inductor and a capacitor. Beneficially, the inductor and the capacitor are in resonance.
In an embodiment, home inverter 104 comprises a DC link capacitor 118 installed between the active front-end AC-DC converter 114 and the high frequency DC-AC resonant converter 116 to minimize voltage ripple between the active front-end AC-DC converter 114 and the high frequency DC-AC resonant converter 116. It is to be understood that the DC link capacitor 118 absorbs electrical energy of the DC link voltage during higher magnitudes of the DC link voltage and releases energy during the lower magnitudes of the DC link voltage. Beneficially, the DC link capacitor 118 alternately stores and releases the electrical energy to minimize the voltage ripples from DC link voltage.
In an embodiment, the control unit 120 is configured to control switching sequence of the pair of switches S1, S2 of each of the switching leg 116a, 116b to convert the DC link voltage received from the active front-end AC-DC converter 114 into a high frequency AC input for the first magnetic coil 106. Beneficially, the control unit 120 controls the switching frequency and the switching sequence of the pair of switches S1, S2.
In an embodiment, the first magnetic coil 106 generates a magnetic field upon receiving the high frequency AC input and the generated magnetic field induces a high frequency AC output in the second magnetic coil 108 of the at least one swappable power pack 102. It is to be understood that the high frequency AC voltage at the output of the high frequency DC-AC resonant converter 116 causes the flow of the high frequency AC current in the first magnetic coil 106. Beneficially, the flow of the high frequency AC current in the first magnetic coil 106 generates the rapidly changing magnetic field in the vicinity of the first magnetic coil 106. It is to be understood that the second magnetic coil 108 of the swappable power pack 102, placed in vicinity of the rapidly changing magnetic field, induces with the high frequency AC output voltage via the magnetic inductance. Beneficially, the high frequency AC output voltage causes the flow of the high frequency AC current in the second magnetic coil 108.
In an embodiment, the at least one swappable power pack 102 comprises: at least one battery module 122, a battery management system 124 and a high frequency bi-directional power converter 126. It is to be understood that the battery module 122, the battery management system 124 and the high frequency bi-directional power converter 126 are included in the swappable power pack 102 to receive the the high frequency AC output current/voltage from the the second magnetic coil 108. The high frequency AC output is converted to DC voltage to charge the battery module 122.
In an embodiment, the high frequency bi-directional power converter 126 is configured to convert the high frequency AC output induced in the second magnetic coil 108 into a DC voltage to charge the at least one battery module 122. It is to be understood that the high frequency bi-directional power converter 126 rectifies the high-frequency AC output into the DC voltage. Beneficially, the high frequency bi-directional power converter 126 is further capable of converting the DC voltage of the at least one battery module 122 into high frequency AC input for the second magnetic coil 108 to enable power backup for domestic loads during the unavailability of the AC grid supply.
In an embodiment, the battery management system 124 manages charging and discharging of the at least one battery module 122. The battery management system 124 monitors a plurality of parameters associated with the at least one battery module 122. It is to be understood that the battery management system 124 monitors the plurality of parameters that includes voltage and current and compares with the rated voltage and current capacity of the battery module 122. Beneficially, the battery management system 124 continues the charging/discharging of the battery module 122 to charge/discharge the battery module 122 within the safe voltage and safe current limit.
In an embodiment, the battery management system 124 is communicably coupled to the high frequency bi-directional power converter 126, to communicate the monitored plurality of parameters associated with the at least one battery module 122 to the high frequency bi-directional power converter 126. It is to be understood that the communication of the parameters from the battery management system 124 to the high frequency bi-directional power converter 126 enables the control unit 130 to precisely control the high frequency bi-directional power converter 126 to generate the DC voltage output suitable for charging the battery module 122 of the swappable battery pack 102.
In an embodiment, the at least one swappable power pack 102 comprises a DC link capacitor 128 installed between the high frequency bi-directional power converter 126 and the battery management system 124 to minimize voltage ripple between the high frequency bi-directional power converter 126 and the battery management system 124. Beneficially, the DC link capacitor 128 alternately stores and releases the electrical energy to minimize the voltage ripples from DC voltage.
In an embodiment, the high frequency bi-directional power converter 126 comprises a plurality of phase inverter legs 126a, 126b wherein each of the phase inverter leg 126a, 126b comprises a pair of switches W1, W2. It is to be understood that the plurality of phase inverter legs 126a, 126b are included in the high frequency bi-directional power converter 126 to connect the switches W1, W2 in a bridge configuration. Beneficially, the phase inverter legs 126a, 126b accommodates and connects the switches W1, W2 in a bridge configuration within the high frequency bi-directional power converter 126.
In an embodiment, the high frequency bi-directional power converter 126 comprises a control unit 130 configured to control plurality of phase inverter legs 126a, 126b. Beneficially, the switches W1, W2 of the plurality of phase inverter legs 126a, 126b are controlled by the control unit 130 to regulate the DC voltage output.
In an embodiment, the control unit 130 is configured to control switching operation of the pair of switches W1, W2 of the plurality of phase inverter legs 126a, 126b to convert the high frequency AC output induced in the second magnetic coil 108 in the DC voltage.
In an embodiment, the high frequency bi-directional power converter 126 supplies the DC voltage to the battery management system 124 to charge the at least one battery module 122. It is to be understood that the battery management system 124 receives the DC voltage from the high frequency bi-directional power converter 126 and regulates the transfer of the DC voltage to the battery module 122. Beneficially, the transfer of the DC voltage to the battery module 122 charges the battery module 122.
In an embodiment, the control unit 130 is configured to control switching operation of the pair of switches W1, W2 of the plurality of phase inverter legs 126a, 126b based on the monitored plurality of parameters associated with the at least one battery module 122, to convert the high frequency AC output in the DC voltage. It is to be understood that the control unit 130 receives the monitored plurality of parameters associated with the battery module 122 from the battery management system 124 to control accordingly the switching operation of the pair of switches W1, W2 of the plurality of phase inverter legs 126a, 126b. Beneficially, the control in switching operation controls the conversion of the high frequency AC output in the DC voltage and thereby the magnitude of the DC voltage that charges the battery module 122. The magnitude of the DC voltage is regulated in accordance to the monitored parameters associated with the battery module 122.
Figure 2, in accordance with an embodiment, describes a circuit diagram of the system 100 for wireless charging of at least one swappable power pack 102. The system 100 comprises the home inverter cum swappable battery charging station 104 and the at least one swappable power pack 102. The home inverter cum swappable battery charging station 104 comprises the first magnetic coil 106. The swappable power pack 102 comprises the second magnetic coil 108. The first magnetic coil 106 and the second magnetic coil 108 form the high-frequency air core transformer 110 to enable transfer of electrical energy between the home inverter 104 and the at least one swappable power pack 102. Furthermore, the home inverter 104 comprises at least one battery pack compartment 112 for receiving and securing the at least one swappable power pack 102. Furthermore, the home inverter 104 comprises the active front-end AC-DC converter 114, wherein the active front-end AC-DC converter 114 comprises the rectification bridge 114a configured to convert AC input received from the power source into DC link voltage. Furthermore, the active front-end AC-DC converter 114 comprises the inductor 114b for power factor correction of the AC input received from the power source. The home inverter 104 comprises the high frequency DC-AC resonant converter 116, wherein the high frequency DC-AC resonant converter 116 comprises at least two switching legs 116a, 116b configured in the bridge configuration, and wherein each of the switching leg 116a, 116b comprises the pair of switches S1, S2. Furthermore, home inverter 104 comprises the DC link capacitor 118 installed between the active front-end AC-DC converter 114 and the high frequency DC-AC resonant converter 116 to minimize voltage ripple between the active front-end AC-DC converter 114 and the high frequency DC-AC resonant converter 116. Furthermore, the control unit 120 is configured to control switching sequence of the pair of switches S1, S2 of each of the switching leg 116a, 116b to convert the DC link voltage received from the active front-end AC-DC converter 114 into the high frequency AC input for the first magnetic coil 106. Furthermore, the first magnetic coil 106 generates the magnetic field upon receiving the high frequency AC input and the generated magnetic field induces the high frequency AC output in the second magnetic coil 108 of the at least one swappable power pack 102. Furthermore, the at least one swappable power pack 102 comprises: at least one battery module 122, the battery management system 124 and the high frequency bi-directional power converter 126. Furthermore, the high frequency bi-directional power converter 126 is configured to convert the high frequency AC output induced in the second magnetic coil 108 into the DC voltage to charge the at least one battery module 122. Furthermore, the battery management system 124 manages charging and discharging of the at least one battery module 122. Furthermore, the battery management system 124 is communicably coupled to the high frequency bi-directional power converter 126, to communicate the monitored plurality of parameters associated with the at least one battery module 122 to the high frequency bi-directional power converter 126. Furthermore, the at least one swappable power pack 102 comprises the DC link capacitor 128 installed between the high frequency bi-directional power converter 126 and the battery management system 124 to minimize voltage ripple between the high frequency bi-directional power converter 126 and the battery management system 124. Furthermore, the high frequency bi-directional power converter 126 comprises the plurality of phase inverter legs 126a, 126b wherein each of the phase inverter leg 126a, 126b comprises the pair of switches W1, W2. Furthermore, the high frequency bi-directional power converter 126 comprises the control unit 130 configured to control plurality of phase inverter legs 126a, 126b. Furthermore, the control unit 130 is configured to control switching operation of the pair of switches W1, W2 of the plurality of phase inverter legs 126a, 126b to convert the high frequency AC output induced in the second magnetic coil 108 in the DC voltage. Furthermore, the high frequency bi-directional power converter 126 supplies the DC voltage to the battery management system 124 to charge the at least one battery module 122. Furthermore, the control unit 130 is configured to control switching operation of the pair of switches W1, W2 of the plurality of phase inverter legs 126a, 126b based on the monitored plurality of parameters associated with the at least one battery module 122, to convert the high frequency AC output in the DC voltage.
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 system (100) for wireless charging of at least one swappable power pack (102), the system (100) comprises:
- a home inverter cum swappable battery charging station (104) comprising a first magnetic coil (106);
- the at least one swappable power pack (102) comprising a second magnetic coil (108),
wherein the first magnetic coil (106) and the second magnetic coil (108) form a high-frequency air core transformer (110) to enable transfer of electrical energy between the home inverter (104) and the at least one swappable power pack (102).
2. The system (100) as claimed in claim 1, wherein the home inverter (104) comprises at least one battery pack compartment (112) for receiving and securing the at least one swappable power pack (102).
3. The system (100) as claimed in claim 1, wherein the home inverter (104) comprises an active front-end AC-DC converter (114), wherein the active front-end AC-DC converter (114) comprises a rectification bridge (114a) configured to convert AC input received from a power source into DC link voltage.
4. The system (100) as claimed in claim 3, wherein the active front-end AC-DC converter (114) comprises an inductor (114b) for power factor correction of the AC input received from the power source.
5. The system (100) as claimed in claim 1, wherein the home inverter (104) comprises a high frequency DC-AC resonant converter (116), wherein the high frequency DC-AC resonant converter (116) comprises at least two switching legs (116a,116b) configured in a bridge configuration, and wherein each of the switching leg (116a,116b) comprises a pair of switches (S1, S2).
6. The system (100) as claimed in claim 1, wherein the home inverter (104) comprises a DC link capacitor (118) installed between the active front-end AC-DC converter (114) and the high frequency DC-AC resonant converter (116) to minimize voltage ripple between the active front-end AC-DC converter (114) and the high frequency DC-AC resonant converter (116).
7. The system (100) as claimed in claim 1, wherein the home inverter (104) comprises a control unit (120) configured to control operation of the active front-end AC-DC converter (114) and the high frequency DC-AC resonant converter (116).
8. The system (100) as claimed in claim 7, wherein the control unit (120) is configured to control switching sequence of the pair of switches (S1, S2) of each of the switching leg (116a,116b) to convert the DC link voltage received from the active front-end AC-DC converter (114) into a high frequency AC input for the first magnetic coil (106).
9. The system (100) as claimed in claim 8, wherein the first magnetic coil (106) generates a magnetic field upon receiving the high frequency AC input and the generated magnetic field induces a high frequency AC output in the second magnetic coil (108) of the at least one swappable power pack (102).
10. The system (100) as claimed in claim 1, wherein the at least one swappable power pack (102) comprises: at least one battery module (122), a battery management system (124) and a high frequency bi-directional power converter (126).
11. The system (100) as claimed in claim 10, wherein the high frequency bi-directional power converter (126) is configured to convert the high frequency AC output induced in the second magnetic coil (108) into a DC voltage to charge the at least one battery module (122).
12. The system (100) as claimed in claim 10, wherein the battery management system (124) manages charging and discharging of the at least one battery module (122).
13. The system (100) as claimed in claim 10, wherein the battery management system (124) monitors a plurality of parameters associated with the at least one battery module (122).
14. The system (100) as claimed in claim 10, wherein the battery management system (124) is communicably coupled to the high frequency bi-directional power converter (126), to communicate the monitored plurality of parameters associated with the at least one battery module (122) to the high frequency bi-directional power converter (126).
15. The system (100) as claimed in claim 10, wherein the at least one swappable power pack (102) comprises a DC link capacitor (128) installed between the high frequency bi-directional power converter (126) and the battery management system (124) to minimize voltage ripple between the high frequency bi-directional power converter (126) and the battery management system (124).
16. The system (100) as claimed in claim 11, wherein the high frequency bi-directional power converter (126) comprises a plurality of phase inverter legs (126a,126b) wherein each of the phase inverter leg (126a,126b) comprises a pair of switches (W1, W2).
17. The system (100) as claimed in claim 11, wherein the high frequency bi-directional power converter (126) comprises a control unit (130) configured to control plurality of phase inverter legs (126a,126b).
18. The system (100) as claimed in claim 17, wherein the control unit (130) is configured to control switching operation of the pair of switches (W1, W2) of the plurality of phase inverter legs (126a,126b) to convert the high frequency AC output induced in the second magnetic coil (108) in the DC voltage.
19. The system (100) as claimed in claim 10, wherein the high frequency bi-directional power converter (126) supplies the DC voltage to the battery management system (124) to charge the at least one battery module (122).
20. The system (100) as claimed in claim 17, wherein the control unit (130) is configured to control switching operation of the pair of switches (W1, W2) of the plurality of phase inverter legs (126a,126b) based on the monitored plurality of parameters associated with the at least one battery module (122), to convert the high frequency AC output in the DC voltage.