DESC:METHOD AND SYSTEM FOR CURRENT BALANCING IN SWAPPABLE
BATTERIES
CROSS REFERENCE TO RELATED APPLICTIONS
The present application claims priority from Indian Provisional Patent Application No. 202321065128 filed on 28/09/2023, the entirety of which is incorporated herein by a reference.
TECHNICAL FIELD
Generally, the present disclosure relates to current balancing in an energy storage system. Particularly, the present disclosure relates to a system for current balancing in an energy storage system. Furthermore, the present disclosure relates to a method of current balancing in an energy storage system.
BACKGROUND
As more industries and consumers shift towards sustainable energy solutions, batteries are becoming essential for powering devices, vehicles, and homes. Technological advancements have also led to more efficient and affordable battery designs. The widespread application of batteries is accelerating battery usage across various sectors.
Recently, the usage of a rechargeable batteries is increased which is driven by the global shift towards sustainability and reducing reliance on fossil fuels. Electric vehicles (EVs) are a key contributor in increasing demand for high-capacity rechargeable batteries. The rechargeable batteries in vehicles, primarily lithium-ion types, are utilized to store and supply electrical energy for propulsion and auxiliary systems. The rechargeable batteries feature high energy density and allowing for extended range and efficiency in electric vehicles (EVs). Furthermore, in electric vehicles, multiple battery cells are connected in parallel to form a module. The cell module enhances the overall capacity and discharge rate of the cell while maintaining a consistent voltage. Moreover, each parallel cell shares the load, thereby reducing the risk of individual cell failure and improving overall performance. The cell modules are grouped together to create a battery pack, which provides the necessary energy storage for the vehicle. Moreover, in a system with multiple battery modules, each equipped with its own BMS and current limiters to manage charging discharging current among the multiple cell modules. Similarly, a battery swapping stations are facilities to exchange the depleted electric vehicle battery with charged battery. The battery swapping stations significantly eliminating the need for extended charging times. Furthermore, multiple batteries of electric vehicles at a swapping station are charged simultaneously, specifically those with varying State of Charge (SOC) levels. In the battery swapping station, each battery has its own BMS to monitor and manage parameters such as voltage, temperature, and state of charge. Moreover, in battery charging station, current limiters are provided to regulate the amount of electrical current flowing into or out of the battery cells of battery pack.
However, in both battery module and the swapping station, each BMS independently controls current flow of cell module and the battery. But when multiple BMS units are involved, coordinating which current limiter to activate at any given time is challenging. Inconsistent activation may lead to imbalanced current distribution, thereby risking overloading, which may affect performance and safety of the cell module or battery pack. Proper synchronization and communication between BMS units are crucial to effectively manage the current limiters across the entire cell module and battery pack.
Therefore, there is a need to provide an improved mechanism that overcomes one or more problems as set forth above.
SUMMARY
An object of the present disclosure is to provide a system for current balancing in an energy storage system.
Another object of the present disclosure is to provide a method of current balancing in an energy storage system
In accordance with an aspect of present disclosure there is provided a system for current balancing in an energy storage system. The system comprises a plurality of module management units, wherein each of the module management unit is coupled to a corresponding energy storage module. Each of the module management unit comprises at least one charge current limiter, at least one discharge current limiter and a control unit. The control unit is configured to determine a state of charge of all the energy storage modules. Furthermore, the control unit compute a mean value and a standard deviation value of the determined state of charges. Moreover, the control unit is configured determine a first threshold value and a second threshold value of the state of charge based on the computed mean value and the computed standard deviation value. Furthermore, the control unit activate the at least one charge current limiter associated with the energy storage modules having the state of charge between the mean value and the first threshold value and activate the at least one discharge current limiter associated with the energy storage modules having the state of charge between the mean value and the second threshold value.
The present disclosure discloses the system for current balancing in an energy storage system. The system for current balancing in an energy storage system as disclosed by present disclosure is advantageously ensuring the efficient charge distribution and prolonging the lifespan of the energy storage modules. Moreover, the system as disclosed by present disclosure is advantageous in terms of incorporating a plurality of module management units, each equipped with dedicated charge current limiter and discharge current limiter, thereby the system ensures precise control of current flow at the individual module level. Beneficially, by dynamically activating charge current limiter and discharge current limiter based on real-time data significantly maintain an optimal state of charge across multiple energy storage modules of the system. The control unit as disclosed by present disclosure is beneficially computing both a mean value and a standard deviation of the state of charge which ensures the energy storage modules are neither overcharged nor excessively discharged, thereby overall system stability is significantly enhanced. Beneficially, the use of thresholds based on operational parameters helps to intelligently regulate the current flow, thereby preventing imbalances that may otherwise lead to inefficient energy use or potential damage of the energy storage system. Additionally, balancing the charge and discharge rates beneficially extends the energy storage modules life by minimizing the risk of over-cycling individual energy storage modules. The extended life of the energy storage module significantly results in reduction of maintenance and operational costs of the energy storage system. Moreover, each module management unit beneficially monitors operational parameters independently which significantly allows real-time adjustments to current limits with the help of the charge current limiters and the discharge current limiters. Beneficially, the real-time current limiting adjustments occurs based on module-specific conditions, such as temperature or state of charge provided by sensor arrangement. Beneficially, the module management unit contributes to longer module life, better energy efficiency, and reduced wear and tear on the energy storage module components. Beneficially, the system of the present disclosure enables battery module paralleling while eliminating the problem of circulating currents.
In accordance with another aspect of present disclosure there is provided a method of current balancing in an energy storage system. At first step, the method comprises determining a state of charge of all energy storage modules of the energy storage system. At second step, the method comprises computing a mean value of the determined state of charges. At third step, the method comprises computing a standard deviation value of the determined state of charges. At fourth step, the method comprises determining a first threshold value and a second threshold value of the state of charge based on the computed mean value and the computed standard deviation value. At fifth step, the method comprises activating the at least one charge current limiter associated with the energy storage modules having the state of charge between the mean value and the first threshold value. At sixth step, the method comprises activating the at least one discharge current limiter associated with the energy storage modules having the state of charge between the mean value and the second threshold value.
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 system for current balancing in an energy storage system, in accordance with an aspect of the present disclosure.
Figure 2 illustrates a flow chart of a method of current balancing in an energy storage system, in accordance with another aspect 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 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 the a system for current balancing in an energy storage 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 “battery management system” and “system” are used interchangeably and refer to an electronic control system designed to monitor, manage, and regulate the performance of an energy storage system, typically comprised of multiple battery cells or modules. The BMS is responsible for ensuring the safe and efficient operation of the battery pack by monitoring key parameters such as voltage, current, temperature, and state of charge (SOC). Additionally, the BMS provides protection by controlling charging and discharging processes, detecting and responding to faults, balancing cell performance, and managing thermal conditions. The system may also include communication interfaces to provide real-time data and control signals for system optimization and fault recovery.
As used herein, the term “energy storage system” refers to a system comprising one or more energy storage modules, such as batteries or other energy storage devices, configured to store electrical energy and supply the energy for use in various applications. The energy storage system may be a battery energy storage system having multiple battery modules. Alternatively, the energy storage system may be a battery swapping station having multiple swappable batteries. The energy storage system may also incorporate control units, sensors, current limiters, and thermal management mechanisms to optimize performance and prevent faults during operation.
As used herein, the term “a plurality of module management units” refers to multiple distinct and independent units within a battery management system (BMS), each of which is responsible for controlling, monitoring, and managing a corresponding energy storage module. Each module management unit (MMU) is configured to perform specific tasks such as monitoring operational parameters (e.g., voltage, temperature, state of charge), managing charge and discharge currents through current limiters, and detecting or responding to faults. The plurality of module management unit operates collectively to ensure efficient and safe management of the entire energy storage system by handling the individual requirements of each connected module.
As used herein, the term “energy storage module” refers to a unit within an energy storage system that is comprised of one or more interconnected energy storage cells, such as battery cells, designed to store and release electrical energy. Each energy storage module includes the necessary components, such as electrical connections, monitoring systems, and thermal management, to operate independently or as part of a larger system. The module is configured to supply electrical energy to a load or store energy.
As used herein, the term “at least one charge current limiter” refers to a component or device within the battery management system configured to regulate and control the maximum electrical current allowed to flow into an energy storage module during the charging process. The purpose of the charge current limiter is to prevent overcurrent conditions that could potentially damage the battery cells, reduce efficiency, or lead to unsafe operating conditions, such as overheating or thermal runaway.
As used herein, the term “at least one discharge current limiter” refers to a component or mechanism within the system that is configured to regulate and limit the amount of current flowing from the energy storage module during the discharge process. This limiter ensures that the discharge current does not exceed a predetermined threshold, thereby preventing potential damage to the energy storage module, protecting the system from overloading, and maintaining safe and efficient operation. The discharge current limiter is designed to activate based on operational parameters and fault conditions, ensuring controlled and optimized discharging of the energy storage module under various operating conditions.
As used herein, the term “control unit” refers to an electronic module configured to monitor, manage, and regulate various operational parameters of the battery or energy storage system. The control unit is responsible for processing input data, such as temperature, voltage, current, and state of charge, received from sensors or module management units. Based on the processed data, the control unit executes control algorithms to optimize the performance and safety of the system. This includes adjusting charging and discharging currents, activating current limiters, balancing cell voltages, detecting faults, and implementing fault recovery protocols to ensure reliable and efficient battery operation. Optionally, the control unit includes, but is not limited to, a microprocessor, a micro-controller, a complex instruction set computing (CISC) microprocessor, a reduced instruction set (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, or any other type of processing circuit. Furthermore, the term “processor” may refer to one or more individual processors, processing devices and various elements associated with a processing device that may be shared by other processing devices. Furthermore, the control unit may comprise ARM Cortex-M series processors, such as the Cortex-M4 or Cortex-M7, or any similar processor designed to handle real-time tasks with high performance and low power consumption. Furthermore, the control unit may comprise custom and/or proprietary processors.
As used herein, the term “sensor arrangement” refers to a collection of sensors strategically integrated within the energy storage system to monitor various operational parameters of the battery modules. This arrangement may include voltage sensors, temperature sensors, current sensors, and state-of-charge (SOC) sensors, among others. The sensors are configured to continuously collect real-time data related to the performance and condition of the battery modules. The information gathered by the sensor arrangement is transmitted to the control unit of the battery management system, enabling it to assess the health of the battery modules, detect faults, and implement corrective actions as necessary to optimize charging and discharging processes.
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 “at least one operational parameter” refers to any measurable variable that characterizes the performance or condition of an energy storage module. The operational parameters may include parameters such as voltage, current, temperature, state of charge (SOC), state of health (SOH), and rate of charge or discharge. These parameters provide critical data for the control unit to assess the operational status of the battery module, enabling it to make informed decisions regarding the management of charge and discharge current limiters, detect faults, and implement appropriate fault recovery strategies. The inclusion of such operational parameters is essential for ensuring optimal performance, safety, and longevity of the energy storage system.
As used herein, the term “a buck converter” refers to a DC-DC power converter designed to step down the voltage from a higher level to a lower level while efficiently regulating the output. In the BMS, the buck converter is used to control the voltage supplied to the battery or specific components within the system, ensuring that the energy storage modules receive the appropriate charging voltage. The buck converter operates by switching transistors at high frequencies and utilizing inductors and capacitors to maintain a stable and reduced output voltage, thereby optimizing energy conversion and minimizing power losses.
As used herein, the term “at least one resistor” refers to an electrical component configured to limit the flow of electric current through a circuit by providing resistance. The resistor is designed to reduce the current to safe levels, preventing overcurrent conditions that could damage the energy storage module or other components of the system. This resistor may be placed in series with the charging or discharging path to regulate the current, ensuring controlled and balanced power flow during battery operation.
As used herein, the term “at least one power switch” refers to an electrical switching component configured to control the connection and disconnection of the battery or battery modules to external circuits or loads. The power switch can regulate the flow of electrical current between the battery and external systems, enabling the BMS to manage charging, discharging, and isolation of the battery in case of faults or other operational conditions. The power switch can be implemented as a relay, transistor, or other suitable switching device, and it is operated by the BMS control unit based on monitored parameters like voltage, current, and temperature. The power switch may include MOSFETs, IGBTs and so on.
As used herein, the term “first threshold” refers to a predefined or dynamically computed value that serves as a boundary for managing the charging current of an energy storage module. The first threshold represents a limit below which the state of charge of a specific module must fall in order to trigger an action, such as activating a charge current limiter. The first threshold value is typically determined using statistical methods, such as calculating the mean value of the state of charge across all modules and may be set between the minimum and mean SoC values.
As used herein, the term “second threshold” refers to a predetermined or dynamically calculated state of charge (SoC) limit, below the computed mean value which is used to regulate the discharge of an energy storage module. This second threshold value serves as a lower boundary to activate a discharge current limiter, ensuring that modules with a state of charge between the mean value and the second threshold are restricted in their discharge to prevent excessive depletion, which could lead to system inefficiencies or potential damage to the energy storage module. The second threshold value is calculated by subtracting a multiple of the computed standard deviation from the mean state of charge. This value adjusts dynamically based on the variation in the state of charge across the energy storage modules.
As used herein, the term “state of charge” and “SOC” are used interchangeably and refer to the current charge level of a rechargeable battery relative to its total capacity, expressed as a percentage. The State of charge (SOC) provides a measure of the remaining energy available in the battery for use, indicating how much charge has been consumed compared to the maximum charge the battery can hold. SOC is a critical parameter in battery management systems, as it influences charging and discharging operations, performance optimization, and overall energy management within an energy storage system.
As used herein, the term “state of health” and “SOH” are used interchangeably and refer to a quantifiable measure that indicates the current condition and performance capability of a battery or energy storage system relative to its original specifications. The SOH is determined based on various factors, including the battery's capacity, internal resistance, and overall efficiency, and is expressed as a percentage of the battery's nominal capacity. A higher SOH value signifies that the battery is functioning optimally, while a lower value indicates degradation or reduced performance, thereby informing decisions regarding maintenance, usage, or replacement of the battery within the energy storage system.
As used herein, the term “state of operation” refers to the current functional condition of an energy storage system or battery, which includes, but is not limited to, operational modes such as charging, discharging, idle, or standby. The state of operation may also encompass transitions between these modes and is determined based on various operational parameters, such as current, voltage, temperature, and system load.
Figure 1, in accordance with an aspect of present disclosure there is provided a system 100 for current balancing in an energy storage system 102. The system 100 comprises a plurality of module management units 104a-n, wherein each of the module management unit 104a-n is coupled to a corresponding energy storage module 106a-n. Each of the module management unit 104a-n comprises at least one charge current limiter 108, at least one discharge current limiter 110 and a control unit 112. The control unit 112 is configured to determine a state of charge of all the energy storage modules 106a-n. Furthermore, the control unit 112 compute a mean value and a standard deviation value of the determined state of charges. Moreover, the control unit 112 is configured determine a first threshold value and a second threshold value of the state of charge based on the computed mean value and the computed standard deviation value. Furthermore, the control unit 112 activate the at least one charge current limiter 108 associated with the energy storage modules 106a-n having the state of charge between the mean value and the first threshold value and activate the at least one discharge current limiter 110 associated with the energy storage modules 106a-n having the state of charge between the mean value and the second threshold value.
The present disclosure discloses the system 100 for current balancing in an energy storage system 102. The system 100 for current balancing in an energy storage system 102 as disclosed by present disclosure is advantageously ensuring the efficient charge distribution and prolonging the lifespan of the energy storage modules 106a-n. Moreover, the system 100 as disclosed by present disclosure is advantageous in terms of incorporating a plurality of module management units 104a-n, each equipped with dedicated charge current limiter 108 and discharge current limiter 110, thereby the system 100 ensures precise control of current flow at the individual module level. Beneficially, by dynamically activating charge current limiter 108 and discharge current limiter 110 based on real-time data significantly maintain an optimal state of charge across multiple energy storage modules 106a-n of the system 100. The control unit 112 as disclosed by present disclosure is beneficially computing both a mean value and a standard deviation of the state of charge which ensures the energy storage modules 106a-n are neither overcharged nor excessively discharged, thereby overall system stability is significantly enhanced. Beneficially, the use of thresholds based on operational parameters helps to intelligently regulate the current flow, thereby preventing imbalances that may otherwise lead to inefficient energy use or potential damage of the energy storage system 102. Additionally, balancing the charge and discharge rates beneficially extends the energy storage modules 106a-n life by minimizing the risk of over-cycling individual energy storage modules 106a-n. The extended life of the energy storage module 106a-n significantly results in reduction of maintenance and operational costs of the energy storage system 102. Moreover, each module management unit 104a-n beneficially monitors operational parameters independently which significantly allows real-time adjustments to current limits with the help of the charge current limiters 108 and the discharge current limiters 110. Beneficially, the real-time current limiting adjustments occurs based on module-specific conditions, such as temperature or state of charge provided by sensor arrangement 114. Beneficially, the module management unit 104a-n contributes to longer module life, better energy efficiency, and reduced wear and tear on the energy storage module components. Beneficially, the system 100 of the present disclosure enables battery module paralleling while eliminating the problem of circulating currents.
In an embodiment, each of the plurality of module management units 104a-n are communicably coupled with each other to communicate the state of charge of the corresponding energy storage module 106a-n. The communication network of the plurality of module management units 104a-n enables the real-time data exchange between the plurality of module management units 104a-n and the energy storge modules 106a-n. Beneficially, the plurality of module management units 104a-n allows synchronized control and coordination of state of charge of the corresponding energy storage module 106a-n across all the energy storage modules 106a-n. Beneficially, the plurality of module management units 104a-n shares the operational parameters such as state of charge, temperature, and fault conditions with the system 100. The system 100 significantly balance the load across all the energy storage modules 106a-n, thereby optimizing energy usage and preventing issues like overcharging or under-discharging of individual energy storage modules 106a-n.
In an embodiment, each of the module management unit 104a-n comprises a sensor arrangement 114. The sensor arrangement 114 is configured to determine the at least one operational parameter associated with the corresponding energy storage module 106a-n. The at least one operational parameter may include, voltage, current, temperature, and state of charge. Beneficially, the sensor arrangement 114 continuously monitors the at least one operational parameter and provides real-time data to the control unit 112 which allows the system 100 for precise management of the charge and discharge processes, thereby ensuring balanced operation and enhanced performance of the energy storage system 102.
In an embodiment, the control unit 112 is communicably coupled to the sensor arrangement 114 to receive the at least one operational parameter associated with the energy storage modules 106a-n. The sensor arrangement 114 is configured to monitor and transmit at least one operational parameter associated with the energy storage modules 106a-n. The control unit 112 receives the at least one operations parameter in real-time, which enables the control unit 112 to make informed decisions regarding charge balancing and the activation of the charge current limiters 108 and the discharge current limiters 110. Beneficially, the control unit 112 ensures optimal performance and protection of the energy storage system 102 by actively monitoring and responding to the conditions of the energy storage modules 106a-n.
In an embodiment, the control unit 112 is configured to determine the state of charge of the energy storage modules 106a-n based on the at least one operational parameter associated with the corresponding energy storage module 106a-n. The at least one operational parameter, which may include voltage, current, and temperature, are received from the sensor arrangement 114 and processed by the control unit 112 to accurately assess the state of charge of each energy storage module 106a-n. Beneficially, the determination of state of charge of each of the energy storage module 106a-n enables the control unit 112 to manage and balance the charge and discharge processes effectively, thereby ensuring optimal functionality and longevity of the energy storage system 102.
In an embodiment, the control unit 112 is configured to set priority of activation of the at least one charge current limiter 108 and activation of the at least one discharge current limiter 110 in an order of the state of charge of the energy storage modules 106a-n. The control unit 112 assigns a higher priority to modules with state of charge values that deviate the most from the computed mean value, thereby ensuring the modules with the highest or lowest state of charge are regulated first. Beneficially, the control unit 112 optimizes the balancing process by addressing the energy storage modules 106a-n that require immediate attention. Beneficially, the process significantly enhances the overall system efficiency and prevents the imbalances that may degrade the performance or lifespan of the energy storage system 102.
In an embodiment, the first threshold value of the state of charge is less than the second threshold value of the state of charge. The threshold condition ensures a clear representation between the operational ranges for the charge current limiters 108 and the discharge current limiters 110, facilitating effective management of energy flow within the energy storage system 102. The energy storage modules 106a-n with a state of charge above the first threshold value but below the mean value may be regulated to limit charging, while those between the mean value and the second threshold value may be controlled to restrict discharging. Beneficially, the threshold values conditions significantly enhance the system’s ability to maintain balance across all energy storage modules 106a-n and optimizes the overall efficiency and longevity of the energy storage system 102.
In an embodiment, the at least one charge current limiter 108 comprises at least one buck converter 116 and at least one resistor 118. The buck converter 116 is designed to efficiently reduce the voltage supplied to the energy storage module 106a-n while regulating the current during the charging process. By stepping down the voltage, the at least one buck converter 116 ensures that the energy storage module 106a-n receives a controlled amount of current, thereby preventing overcharging and prolonging the lifespan of the energy storage module 106a-n. Moreover, the at least one resistor 118 serves as an additional safety measure, providing a passive means to limit current flow and dissipate excess energy as heat, further safeguarding the module from potential damage. Beneficially, the combination of the at least one buck converter 116 and the at least one resistor 118 ensures the energy storage modules 106a-n operate within safe parameters, thereby enhancing the reliability and longevity of the battery management system 100 while providing optimal charging performance.
In an embodiment, the at least one discharge current limiter 110 comprises at least one buck converter 116 and at least one resistor 118. During discharge, the at least one buck converter 116 is configured to regulate and reduce the voltage during the discharging process and ensure a controlled and stable current flow from the energy storage module 106a-n to the load, thereby preventing excessive current discharge that could damage the energy storage module 106a-n. Moreover, by stepping down the voltage, the buck converter ensures that the discharge current remains within safe operating limits, preventing excessive current draw that could damage the energy storage module 106a-n. Furthermore, the resistor 118 serves as a passive component to limit the discharge current further, thereby providing additional protection by dissipating excess energy in the form of heat. Beneficially, the discharge current limiter 110 has precise control over discharge current, which helps to prevent rapid degradation of the battery cells, thereby extending the overall life of the energy storage system 102.
Figure 2, describes a method 200 of current balancing in an energy storage system 102. The method 200 starts at step 202 and completes at step 212. At step 202, the method 200 comprises determining a state of charge of all energy storage modules 106a-n of the energy storage system 102. At step 204, the method 200 comprises computing a mean value of the determined state of charges. At step 206, the method 200 comprises computing a standard deviation value of the determined state of charges. At step 208, the method 200 comprises determining a first threshold value and a second threshold value of the state of charge based on the computed mean value and the computed standard deviation value. At step 210, the method 200 comprises activating the at least one charge current limiter 108 associated with the energy storage modules 106a-n having the state of charge between the mean value and the first threshold value. At step 212, the method 200 comprises activating the at least one discharge current limiter 110 associated with the energy storage modules 106a-n having the state of charge between the mean value and the second threshold value.
It would be appreciated that all the explanations and embodiments of the system 100 also applies mutatis-mutandis to the method 200.
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 energy storage system (102), wherein the battery management system (100) comprises a plurality of module management units (104a-n), wherein each of the module management unit (104a-n) is coupled to a corresponding energy storage module (106a-n), wherein each of the module management unit (104a-n) comprises:
- at least one charge current limiter (108);
- at least one discharge current limiter (110); and
- a control unit (112) configured to:
- receive at least one operational parameter associated with the energy storage module (106a-n);
- determine at least one fault and/or fault recovery associated with the energy storage module (106a-n); and
- operate the at least one charge current limiter (108) and/or the at least one discharge current limiter (110) based on the at least one operational parameter and the at least one fault and/or fault recovery associated with the energy storage module (106a-n) to manage charging or discharging of the respective energy storage module (106a-n).
2. The battery management system (100) of claim 1, wherein each of the plurality of module management units (104a-n) are communicably coupled with each other to manage the charging and/or discharging of the energy storge modules (106a-n).
3. The battery management system (100) of claim 2, wherein each of the control unit (112) is configured to receive the at least one operational parameter and the at least one fault and/or fault recovery associated with all the energy storage modules (106a-n).
4. The battery management system (100) of claim 3, wherein each of the control unit (112) is configured to operate the at least one charge current limiter (108) and/or the at least one discharge current limiter (110) based on the received at least one operational parameter associated with all the energy storage modules (106a-n).
5. The battery management system (100) of claim 3, wherein each of the control unit (112) is configured to operate the at least one charge current limiter (108) and/or the at least one discharge current limiter (110) based on the at least one fault and/or fault recovery associated with all the energy storage modules (106a-n).
6. The battery management system (100) of claim 1, wherein each of the module management unit (104a-n) comprises a sensor arrangement (114), and wherein the sensor arrangement (114) is configured to determine the at least one operational parameter associated with the energy storage module (106a-n).
7. The battery management system (100) of claim 1, wherein the at least one charge current limiter (108) comprises at least one of: a buck converter (116) and at least one resistor (118).
8. The battery management system (100) of claim 1, wherein the at least one discharge current limiter (110) comprises at least one of: a buck converter (116) and at least one resistor (118).
9. The battery management system (100) of claim 1, wherein each of the module management unit (104a-n) comprises at least one power switch (120) configured to electrically connect and/or disconnect the respective energy storage module (106a-n) with rest of the energy storage modules (106b-n).
10. The battery management system (100) of claim 9, wherein the control unit (112) is configured to control the at least one power switch (120) to electrically connect and/or disconnect the respective energy storage module (106a-n) with rest of the energy storage modules (106b-n) based on the at least one fault and/or fault recovery.