DESC:BATTERY MANAGEMENT SYSTEM FOR ELECTRIC VEHICLE(S)
CROSS REFERENCE TO RELATED APPLICATIONS
The present application claims priority from Indian Provisional Patent Application No. 202421002001 filed on 11/01/2024, the entirety of which is incorporated herein by a reference.
TECHNICAL FIELD
Generally, the present disclosure relates to electric vehicles. Particularly, the present disclosure relates to a battery management system for electric vehicle.
BACKGROUND
The increasing demand for more economical and efficient vehicles, along with consumer preferences for higher-performance batteries, compels automobile manufacturers to innovate in order to satisfy these needs. As a result, the automotive industry has consistently worked to improve battery packs with modular battery management systems, aiming for better safety and simplified maintenance and servicing.
Conventionally, a Battery Management System (BMS) usually comprises of integrated components that function as a single, cohesive unit to manage various aspects of a battery pack. The primary components of a BMS include a battery monitoring unit (BMU), a controller, a balancing circuit, and a protection circuit. The Battery Monitoring Unit (BMU) oversees voltage, current, and temperature monitoring of individual cells. Further, the controller makes decisions based on data from the BMU and the balancing circuit ensures uniform charge across all battery cells. Subsequently, the protection circuit safeguards the powerpack and/or system associated from the conditions such as overcharging, over-discharging, over current, over voltage, overheating and so forth. The components are integrated as a single unit, and the entire BMS is designed to function as a single, monolithic unit with a simplified design making the initial system setup faster and less complex.
However, the battery management system is also required to perform critical safety functions in the electric vehicles. For instance, the battery management system is required to maintain isolation between the chassis of the vehicle and the battery pack to prevent any leakage current and keep the user safe. In the conventional battery management systems, such critical safety functions may be processed slowly leading to critical safety risks.
Therefore, there exists a need of an improved battery management system that overcomes one or more problems as mentioned above.
SUMMARY
An object of the present disclosure is to provide a battery management system.
In accordance with an aspect of present disclosure there is provided a battery management system for an electric vehicle. The battery management system comprises an isolation resistance measurement unit configured to determine isolation resistance between a chassis and a battery pack, a short circuit detection unit configured to detect a short circuit, and a terminal cover sensing unit configured to detect removal of at least one terminal cover from terminals of the battery pack.
The battery management system of the present disclosure is advantageous in terms of accurate and timely determination of the isolation resistance. Furthermore, the battery management system of the present disclosure is advantageous in terms of detecting short circuits inside or outside the battery pack. Furthermore, the battery management system of the present disclosure is advantageous in terms of detecting exposure of terminals of the battery pack. Beneficially, the battery management system of the present disclosure cuts off the power supply from the battery pack in case any safety critical issue including short circuit, terminal cover removal and/or detection of decreased isolation resistance.
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:
Figure 1 illustrates a block diagram of a battery management system, in accordance with an aspect of 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 recognise that other embodiments for carrying out or practising 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 battery management system and is not intended to represent the only forms that may be developed or utilised. 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 minimised 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.
As used herein, the terms “comprise”, “comprises”, “comprising”, “include(s)”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, 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, and 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 refer to any vehicle having stored electrical energy, including the vehicle capable of being charged from an external electrical power source. This may include vehicles having batteries which are exclusively charged from an external power source, as well as hybrid-vehicles which may include batteries capable of being at least partially recharged via an external power source. Additionally, it is to be understood that the ‘electric vehicle’ as used herein includes electric two-wheeler, electric three-wheeler, electric four-wheeler, electric pickup trucks, electric trucks and so forth.
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.
As used herein, the terms “battery management system” and “BMS” are used interchangeably and refer to an electronic system that manages and monitors the performance, health, and safety of the vehicle battery pack. Further, the BMS ensures optimal battery operation by managing various functions such as (but not limited to) charging, discharging, temperature control, and state of charge assessment. Furthermore, the BMS protects the battery from potential hazards such as overcharging, deep discharging, and thermal runaway, thereby enhancing battery life and performance.
As used herein, the terms “battery pack” and “powerpack” are used interchangeably and refer to an assembled unit of a plurality of cell arrays that are connected electrically to form a larger energy storage capable of delivering the required amount of energy for high-power applications. The battery modules may be arranged in series or parallel configurations depending on the desired voltage and capacity requirements. The battery modules of the powerpack connected in series increase the overall voltage of the energy storage system. The electrical connections in the powerpack are formed by connecting the terminals of the battery cells with bus bars. Furthermore, in addition to the individual cells, a powerpack also includes circuitry for balancing the charge levels of the cells, managing the charging and discharging processes, and providing safety features such as overcharge and over-discharge protection. The powerpack, along with the associated electronics and packaging, forms the core component of an energy storage system, enabling the efficient and reliable storage and delivery of electrical energy.
As used herein, the term “processing unit” refers to a central component of an embedded system or electronic device responsible for managing and executing tasks based on input data, making decisions, and controlling other system components. The processing unit comprises a microcontroller (MCU) or microprocessor (CPU), memory modules (RAM and ROM), and input/output interfaces. The microcontroller or processor executes software instructions to process data from sensors (such as, but not limited to, temperature, current, or voltage), perform calculations, and make control decisions. The memory stores the program code and runtime data, and the input/output interfaces allow communication with other devices or modules. The processing unit performs by receiving sensor inputs, processing them according to predefined algorithms or logic, and then sending control signals to actuators or other parts of the system, enabling the required functions.
As used herein, the term “isolation resistance measurement unit” refers to an electronic unit of the battery management system capable of determining isolation resistance between different components of the vehicle.
As used herein, the term “short circuit detection unit” refers to an electronic unit of the battery management system capable of detecting short circuits inside the battery pack or outside the battery pack in the electric vehicle.
As used herein, the terms “switching devices”, and “switches” are used interchangeably and refer to the components that controls the flow of electricity to and from the battery pack, ensuring safe and efficient transmission from the battery pack. The switching devices comprise MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors), relays, and contactors. The MOSFETs are used for high-speed switching and controlling charge and discharge currents. The relays and contactors isolate the battery during fault conditions or during switching between charge and discharge modes. The switching devices functions by receiving control signals from the BMS, which monitors battery health, temperature, and voltage. When a specific condition (such as overvoltage, undervoltage, or thermal overload) is detected, the switching devices open or close the circuit, either allowing or cutting off power to the battery or external load, thus protecting the battery from damage and ensuring optimal performance.
Figure 1, in accordance with an embodiment describes a battery management system 100 for an electric vehicle. The battery management system 100 comprises an isolation resistance measurement unit 102 configured to determine isolation resistance between a chassis 112 and a battery pack 114, a short circuit detection unit 104 configured to detect a short circuit, and a terminal cover sensing unit 106 configured to detect removal of at least one terminal cover from terminals of the battery pack 114.
The battery management system 100 of the present disclosure is advantageous in terms of accurate and timely determination of the isolation resistance. Furthermore, the battery management system 100 of the present disclosure is advantageous in terms of detecting short circuits inside or outside the battery pack 114. Furthermore, the battery management system 100 of the present disclosure is advantageous in terms of detecting exposure of terminals of the battery pack 114. Beneficially, the battery management system 100 of the present disclosure cuts off the power supply from the battery pack 114 in case any safety critical issue including short circuit, terminal cover removal and/or detection of decreased isolation resistance.
In an embodiment, the isolation resistance measurement unit 102 comprises at least one switch 102a and a low voltage signal generator 102b. In an embodiment, the low voltage signal generator 102b is configured to generate a resistance detection signal and the at least one switch 102a is configured to direct the generated signal to the chassis 112. Beneficially, the low voltage signal generator 102b generates the signal and the least one switch 102a directs the low voltage signal to the chassis 112 for measuring the isolation resistance between the chassis 112 and the battery pack 114.
In an embodiment, the isolation resistance measurement unit 102 determines the isolation resistance between the chassis 112 and the battery pack 114 based on a response of the generated signal directed to the chassis 112. Beneficially, the isolation resistance measurement unit 102 detects if the low voltage signal directed to the chassis 112 is delivered and generates response. If the response is generated, the isolation resistance is determined from that response.
In an embodiment, the short circuit detection unit 104 is configured to employ a noise reduction mechanism 104a to detect the short circuit. Beneficially, the noise reduction mechanism 104a prevents false triggers and improves the robustness of short circuit detection by the short circuit detection unit 104.
In an embodiment, the noise reduction mechanism 104a comprises a counter circuit 104b configured to count number of triggers occurring during a predefined time period, and confirm the short circuit if the number of triggers exceeds a threshold in the predefined time period. Beneficially, the counter circuit 104b counts the number of triggers in predefined time period to reduce detection of any false triggers and improve the accuracy and robustness.
In an embodiment, the terminal cover sensing unit 106 comprises at least one proximity sensor 106a to detect removal of the at least one terminal cover from the terminals of the battery pack 114. Beneficially, the proximity sensor 106a continuously monitors the presence of the at least one terminal cover on the terminals of the battery pack 114 and detect if the cover is removed.
In an embodiment, the battery management system 100 comprises a power shutdown unit 108 communicably coupled to the isolation resistance measurement unit 102, the short circuit detection unit 104 and the terminal cover sensing unit 106. Beneficially, the power shutdown unit 108 cuts-off power supply from the battery pack 114 in case of detection of any safety critical fault.
In an embodiment, the power shutdown unit 108 is configured to cut-off power supply from the battery pack 114, when the determined isolation resistance is below a predefined threshold; the short circuit is detected; or the at least one terminal cover is removed from the terminals of the battery pack 114. Beneficially, the power shutdown unit 108 prevents any damage to other components of the vehicle or any danger to a user of the vehicle.
In an embodiment, the battery management system 100 comprises a wakeup unit 110 configured to detect a wakeup signal received from a charger and wake-up the battery management system 100 from a vacation mode. Beneficially, the wakeup unit 110 enables the functioning of other components of the battery management system 100 after the termination of the vacation mode.
In an embodiment, battery management system 100 comprises the isolation resistance measurement unit 102 configured to determine the isolation resistance between the chassis 112 and the battery pack 114, the short circuit detection unit 104 configured to detect the short circuit, and the terminal cover sensing unit 106 configured to detect removal of at least one terminal cover from terminals of the battery pack 114. Furthermore, the isolation resistance measurement unit 102 comprises the at least one switch 102a and the low voltage signal generator 102b. Furthermore, the low voltage signal generator 102b is configured to generate the resistance detection signal and the at least one switch 102a is configured to direct the generated signal to the chassis 112. Furthermore, the isolation resistance measurement unit 102 determines the isolation resistance between the chassis 112 and the battery pack 114 based on the response of the generated signal directed to the chassis 112. Furthermore, the short circuit detection unit 104 is configured to employ the noise reduction mechanism 104a to detect the short circuit. Furthermore, the noise reduction mechanism 104a comprises the counter circuit 104b configured to count number of triggers occurring during the predefined time period, and confirm the short circuit if the number of triggers exceeds a threshold in the predefined time period. Furthermore, the terminal cover sensing unit 106 comprises the at least one proximity sensor 106a to detect removal of the at least one terminal cover from the terminals of the battery pack 114. Furthermore, the battery management system 100 comprises the power shutdown unit 108 communicably coupled to the isolation resistance measurement unit 102, the short circuit detection unit 104 and the terminal cover sensing unit 106. Furthermore, the power shutdown unit 108 is configured to cut-off power supply from the battery pack 114, when the determined isolation resistance is below the predefined threshold; the short circuit is detected; or the at least one terminal cover is removed from the terminals of the battery pack 114. Furthermore, the battery management system 100 comprises the wakeup unit 110 configured to detect the wakeup signal received from the charger and wake-up the battery management system 100 from the vacation mode.
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 combination 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”, “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 battery management system (100) for an electric vehicle, wherein the battery management system (100) comprises:
- an isolation resistance measurement unit (102) configured to determine isolation resistance between a chassis (112) and a battery pack (114);
- a short circuit detection unit (104) configured to detect a short circuit; and
- a terminal cover sensing unit (106) configured to detect removal of at least one terminal cover from terminals of the battery pack (114).
2. The battery management system (100) as claimed in claim 1, wherein the isolation resistance measurement unit (102) comprises at least one switch (102a) and a low voltage signal generator (102b).
3. The battery management system (100) as claimed in claim 2, wherein the low voltage signal generator (102b) is configured to generate a resistance detection signal and the at least one switch (102a) is configured to direct the generated signal to the chassis (112).
4. The battery management system (100) as claimed in claim 3, wherein the isolation resistance measurement unit (102) determines the isolation resistance between the chassis (112) and the battery pack (114) based on a response of the generated signal directed to the chassis (112).
5. The battery management system (100) as claimed in claim 1, wherein the short circuit detection unit (104) is configured to employ a noise reduction mechanism (104a) to detect the short circuit.
6. The battery management system (100) as claimed in claim 5, wherein the noise reduction mechanism (104a) comprises a counter circuit (104b) configured to count number of triggers occurring during a predefined time period, and confirm the short circuit if the number of triggers exceeds a threshold in the predefined time period.
7. The battery management system (100) as claimed in claim 1, wherein the terminal cover sensing unit (106) comprises at least one proximity sensor (106a) to detect removal of the at least one terminal cover from the terminals of the battery pack (114).
8. The battery management system (100) as claimed in claim 1, wherein the battery management system (100) comprises a power shutdown unit (108) communicably coupled to the isolation resistance measurement unit (102), the short circuit detection unit (104) and the terminal cover sensing unit (106).
9. The battery management system (100) as claimed in claim 8, wherein the power shutdown unit (108) is configured to cut-off power supply from the battery pack (114), when:
- the determined isolation resistance is below a predefined threshold;
- the short circuit is detected; or
- the at least one terminal cover is removed from the terminals of the battery pack (114).
10. The battery management system (100) as claimed in claim 1, wherein the battery management system (100) comprises a wakeup unit (110) configured to detect a wakeup signal received from a charger and wake-up the battery management system (100) from a vacation mode.