A wireless parallel battery module

Abstract

This invention provides a wireless parallel battery module, comprising several battery module units connected in parallel to the HV bus. Each battery module unit includes a first module and a second module. The first module includes a first rectifier-inverter circuit and a first coil; the second module includes a cell unit, a battery management system, a second rectifier-inverter circuit, and a second coil. The first module and the second module achieve bidirectional mutual inductive coupling through the connection of the first coil and the second coil. The battery management system is connected to both the cell unit and the second rectifier-inverter circuit, and is used to monitor and manage the operating status of the cell unit and control the operating status and power output of the second rectifier-inverter circuit. Each battery module unit of this invention is equipped with an independent power circuit and a battery management system, and achieves bidirectional energy transfer between the battery module and the HV bus through magnetic coupling, making the expansion of the battery module more flexible and convenient.

Description

Technical Field

[0001] This utility model relates to the field of wireless power transmission technology, and in particular to a wireless parallel battery module. Background Technology

[0002] A residential energy storage battery is a large rechargeable battery system installed in a home. Its primary function is to store electrical energy and release it when needed, thereby achieving home electricity self-sufficiency, saving on electricity bills, and improving power supply reliability.

[0003] Currently, the connection between battery packs in residential energy storage battery systems mainly relies on wired cables for electrical connection. The positive and negative terminals of the battery packs are connected in series or parallel according to the topology of the system design, thereby expanding the capacity or increasing the voltage. The system usually selects a host unit from the battery packs mounted on the high-voltage DC bus (HV bus). The battery management system realizes data acquisition and centralized control of the battery pack through interaction with the host unit.

[0004] In residential energy storage systems employing high-capacity, low-series-count cells, the low output voltage of the battery pack typically necessitates a DC-DC booster module to raise the voltage to match the HV bus level. Furthermore, communication between battery packs and between battery packs and the battery management system currently primarily relies on wired methods, such as RS-485 or CAN bus protocols, which significantly limits flexibility, scalability, and ease of maintenance. Utility Model Content

[0005] To address the problems existing in the prior art, this utility model discloses a wireless parallel battery module, aiming to solve the problems of flexibility, scalability and maintenance convenience of traditional wired parallel connection methods.

[0006] The objective of this utility model is achieved through the following technical solution:

[0007] This utility model provides a wireless parallel battery module, including a plurality of battery module units connected in parallel to the HV bus, each of the battery module units including a first module and a second module; The first module includes a first rectifier-inverter circuit and a first coil. The DC side of the first rectifier-inverter circuit is connected to the HV bus, and its AC side is connected to the first coil. The second module includes a cell unit, a battery management system, a second rectifier-inverter circuit, and a second coil. The DC side of the second rectifier-inverter circuit is connected to the cell unit, and its AC side is connected to the second coil. The first module and the second module achieve bidirectional mutual inductive coupling through the docking of the first coil and the second coil, forming a non-contact power transmission path; The first rectifier-inverter circuit is configured as follows: During charging, the high-voltage DC power from the HV bus is rectified and inverted into high-frequency AC power, which is then output through the first coil. During discharge, the high-frequency AC power from the first coil is rectified and inverted into high-voltage DC power and fed back to the HV bus. The second rectifier-inverter circuit is configured as follows: During discharge, the low-voltage DC power output from the battery cell unit is rectified and inverted into high-frequency AC power, and then output through the second coil; During charging, the high-frequency AC power from the second coil is rectified and inverted into low-voltage DC power to charge the battery cell unit; The battery management system is connected to the battery cell and the second rectifier-inverter circuit respectively, and is used to monitor and manage the working status of the battery cell and control the working status and power output of the second rectifier-inverter circuit.

[0008] Furthermore, the first module of each battery module unit is packaged to form an independent energy interface module, which is fixedly installed in the battery cabinet and electrically connected to the HV bus; the second module of each battery module unit is packaged to form an independent energy storage module, which is fixedly installed in a preset slot in the battery cabinet; the energy interface module is physically connected and fixed to the second coil of the energy storage module through the first coil.

[0009] Furthermore, the battery management system includes a power supply unit, an AFE acquisition unit, a charge / discharge control unit, a wireless communication unit, and a second main control unit; The power supply unit is connected to the AFE acquisition unit, the charge and discharge control unit, the wireless communication unit, and the second main control unit, respectively, and is configured to provide operating voltage to each unit. The second main control unit is connected to the AFE acquisition unit, the charge / discharge control unit, and the wireless communication unit respectively, and is configured to run control algorithms, process data, and coordinate the work of each unit; The AFE acquisition unit is connected to the cell unit and is configured to acquire signals from the cell unit and transmit the acquired signals to the second main control unit; The charge / discharge control unit is connected to the second main control unit and the battery cell unit respectively, and is configured to receive instructions from the second main control unit and control the battery cell unit to charge and discharge. The wireless communication unit is connected to the second main control unit and configured to communicate wirelessly with the external first main control unit.

[0010] Furthermore, the battery management system also includes a thermal management unit, which is connected to the second main control unit and the cell unit respectively, and is configured to perform heating or heat dissipation operations according to the instructions of the second main control unit.

[0011] Furthermore, the battery management system also includes a storage unit connected to the second main control unit and configured to store data from the AFE acquisition unit and data processed by the second main control unit.

[0012] Furthermore, the plurality of battery module units include a main battery module unit and at least one slave battery module unit; The main battery module unit communicates with the external first main control unit through its wireless communication unit, and is used to receive the control signal from the first main control unit and forward the control signal to the wireless communication unit of each of the slave battery module units. Each of the slave battery module units sends its own operating status information to the main battery module unit through its wireless communication unit; The main battery module unit is further configured to receive and summarize the operating status information and its own status information of each of the slave battery module units, and interact with the first main control unit.

[0013] Furthermore, the second main control unit is also configured as follows: Based on the data collected by the AFE acquisition unit, the state of charge (SOC) and state of health (SOH) of the battery cell are estimated and evaluated using a preset algorithm.

[0014] Furthermore, the second main control unit is also configured as follows: Real-time monitoring of the voltage and current of the battery cell unit; When the voltage or current exceeds a preset safety threshold, the charging and discharging control unit is controlled to perform a protection action.

[0015] Furthermore, the battery module unit also includes a first inductor and a second inductor, and a second compensation network is provided between the second rectifier-inverter circuit and the second inductor; a first compensation network is provided between the first rectifier-inverter circuit and the first inductor; the first compensation network and the second compensation network are used to adjust the circuit resonance characteristics.

[0016] Furthermore, the battery module unit also includes a first driving circuit, a second driving circuit, a first main control unit, and a second main control unit; The first driving circuit is connected to the first main control unit and the first rectifier-inverter circuit respectively, and is used to receive control commands issued by the first main control unit and drive the power switching devices in the first rectifier-inverter circuit. The second drive circuit is connected to the second main control unit and the second rectifier-inverter circuit respectively, and is used to receive control commands issued by the second main control unit and drive the power switching devices in the second rectifier-inverter circuit.

[0017] Compared with existing technologies, the advantages of this invention are as follows: Each battery module unit is equipped with an independent power circuit and a BMS battery management system, achieving bidirectional energy transfer between the battery module and the HV bus through magnetic coupling. While achieving energy transfer, electrical isolation is also implemented, thus limiting faults to a single module unit, resulting in strong fault isolation. During maintenance, faulty module units can be directly replaced without system downtime, greatly improving system reliability and maintenance convenience. Furthermore, this architecture enables true plug-and-play expansion; adding new battery module units requires no hardware modifications or software reconfiguration of the existing system, significantly improving system flexibility and scalability. Attached Figure Description

[0018] Figure 1 This invention illustrates a modular architecture diagram of a wireless parallel battery module. Figure 2 A modular structure diagram of the battery module unit of this utility model is shown; Figure 3 A system structure diagram based on the wireless parallel battery module of this utility model is shown; Figure 4 This invention shows a structural diagram of the second module of the battery module unit. Figure 5 The diagram shows the bidirectional mutual inductance circuit structure of the battery module unit of this utility model. Detailed Implementation

[0019] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0020] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0022] Figure 1 This diagram illustrates the modular architecture of the wireless parallel battery module of this invention, including several battery module units connected in parallel to the HV bus. Each battery module unit includes a first rectifier-inverter circuit (DC / AC), a coupling inductor, a second rectifier-inverter circuit (AC / DC), a BMS battery management system, and a cell unit. During charging (energy flows from the external power grid or photovoltaic power to the battery), the high-voltage DC power on the HV bus is input to the first rectifier-inverter circuit (DC / AC) and rectified and inverted into high-frequency AC power. This high-frequency AC power undergoes energy transfer and filtering through the coupling inductor, and is then rectified and inverted into low-voltage DC power by the second rectifier-inverter circuit (AC / DC). Under the intelligent control of the BMS battery management system, this DC power is stored in the cell unit. During discharge (energy flows from the battery to the load), the low-voltage DC power from the battery cell is rectified and inverted into high-frequency AC power by the second rectifier-inverter circuit (AC / DC). This high-frequency AC power is then rectified and inverted back into high-voltage DC power by the first rectifier-inverter circuit (DC / AC) after energy transfer and filtering through a coupling inductor. Finally, it is fed into the HV bus for unified output to power the load.

[0023] Specifically, in combination Figure 2 , 3As shown, each battery module unit has an independent first module and a second module. The first module includes a first rectifier-inverter circuit and a first coil. The DC side of the first rectifier-inverter circuit is connected to the HV bus, and its AC side is connected to the first coil. The second module includes a cell unit, a battery management system, a second rectifier-inverter circuit, and a second coil. The DC side of the second rectifier-inverter circuit is connected to the cell unit, and its AC side is connected to the second coil. The first and second modules achieve bidirectional mutual inductive coupling through the docking of the first and second coils, forming a contactless power transmission path. Specifically, during charging, the first rectifier-inverter circuit rectifies and inverts the high-voltage DC power from the HV bus into high-frequency AC power and outputs it through the first coil. During discharging, it rectifies and inverts the high-frequency AC power from the first coil into high-voltage DC power and feeds it back to the HV bus. During discharging, the second rectifier-inverter circuit rectifies and inverts the low-voltage DC power output from the cell unit into high-frequency AC power and outputs it through the second coil. During charging, it rectifies and inverts the high-frequency AC power from the second coil into low-voltage DC power to charge the cell unit. The battery management system is connected to the battery cell unit and the second rectifier-inverter circuit respectively. It is used to monitor and manage the working status of the battery cell unit and control the working status and power output of the second rectifier-inverter circuit.

[0024] In addition, each battery module unit also has a first drive circuit and a second drive circuit. The first drive circuit is connected to the first main control unit and the first rectifier-inverter circuit, and is used to receive control commands issued by the first main control unit and drive the power switching devices in the first rectifier-inverter circuit based on the control commands. It should be noted that... Figure 3 Only the first drive circuit included in one of the battery module units is shown in the figure; drive circuits with the same structure in the other battery module units are omitted in the figure. The second drive circuit is connected to the second main control unit and the second rectifier-inverter circuit, and is used to receive control commands issued by the second main control unit and drive the power switching devices in the second rectifier-inverter circuit based on the control commands.

[0025] The modular design of this battery module unit significantly improves the safety and operational reliability of wireless parallel battery module systems. Specifically, the design divides the battery module unit into two independent modules. The first module is encapsulated as an independent energy interface module, fixedly installed within the battery cabinet and electrically connected to the HV bus. The second module is encapsulated as an independent energy storage module, which can be inserted into a pre-designated battery slot within the battery cabinet. The energy interface module has a first coil, and the energy storage module has a second coil; the two are fixed and coupled through physical docking. The battery cabinet has no external electrical connectors. Users simply place the fully encapsulated energy storage module into the designated slot within the cabinet. Mechanical positioning automatically aligns and tightly engages the second coil of the energy storage module with the first coil of the energy interface module, completing the electrical connection and system expansion—truly plug-and-play.

[0026] Furthermore, combined with Figure 4 As shown, the battery management system (BMS) of this invention mainly includes a power supply unit, an AFE (Active Factor Estimation) acquisition unit, a charge / discharge control unit, a wireless communication unit, a second main control unit, a thermal management unit, and a storage unit. The second main control unit, as the core controller of the BMS, is connected to the AFE acquisition unit, the charge / discharge control unit, and the wireless communication unit. It is responsible for the overall scheduling, data processing, and algorithm execution of the system. Specific functions include estimating the state of charge (SOC) and state of health (SOH) of the battery cells based on the data collected by the AFE acquisition unit, monitoring the voltage and current of the battery cells in real time, and controlling the charge / discharge control unit through algorithms to achieve fault protection such as overvoltage, overcurrent, and undervoltage. Simultaneously, it saves the processed key data to the storage unit. The AFE acquisition unit is connected to the battery cells and is responsible for the synchronous acquisition of multiple battery cell signals, including voltage, current, and temperature, and transmits the acquired signals to the second main control unit. The power supply unit is connected to the AFE acquisition unit, the charge / discharge control unit, the wireless communication unit, and the second main control unit, providing a stable and isolated operating power supply voltage for the control circuit, drive circuit, and various main chips of the power main circuit in the BMS. The charge / discharge control unit is connected to both the second main control unit and the cell unit. It receives commands from the second main control unit and directly controls the on / off state of the charge / discharge circuit, managing the charge / discharge process of the cell unit. The wireless communication unit is connected to the second main control unit and is responsible for wireless data exchange with the first main control unit and other second main control units of the battery management system, supporting system-level coordination and control. The thermal management unit is connected to both the second main control unit and the cell unit. It performs heating or cooling operations according to commands from the second main control unit, ensuring the battery operates within a suitable temperature range, extending its lifespan and improving safety. The storage unit is connected to the second main control unit and stores raw data from the AFE acquisition unit and processed data from the second main control unit, supporting system operation logs and historical status queries.

[0027] Furthermore, this utility model's wireless parallel battery module adopts a master-slave communication network architecture based on SN codes. The system automatically elects one master battery module unit, and the others are slave battery module units. The master battery module unit is responsible for managing all slave battery module units and communicating with the superior first master control unit. The slave battery module units obey the instructions of the master battery module unit and report their own status to the master battery module unit. Specifically, the wireless communication unit of the master battery module unit establishes a communication connection with the first master control unit to receive system-level control signals from the first master control unit and forward these control signals to the wireless communication units of each slave battery module unit. The wireless communication units in each slave battery module unit send their module's operating status information to the master battery module unit. The wireless communication units in the master battery module unit are used to receive and summarize the operating status information of all slave battery module units and their own status information, and interact with the first master control unit.

[0028] Furthermore, combined with Figure 5 As shown, a second compensation network is provided between the second rectifier-inverter circuit and the second inductor. A first compensation network is provided between the first rectifier-inverter circuit and the first inductor. Both the first and second compensation networks are composed of LCCL filters, used to filter out switching noise and shape a sine wave output, thereby improving power quality and reducing electromagnetic interference. When the residential energy storage system is in operation, the DC power output from the cell unit is converted into high-frequency AC power by the second rectifier-inverter circuit, and then the resonant characteristics of the circuit are adjusted by the second compensation network to achieve better impedance matching. Subsequently, the power is wirelessly transmitted through the mutual inductance between the second and first coils. The high-frequency AC power received by the first coil is filtered by the first compensation network and then sent to the first rectifier-inverter circuit for rectification and voltage regulation filtering, finally outputting a stable DC voltage to the HV bus by the battery module unit. During rectification and inversion, the first and second drive circuits receive wireless control commands from the first and second main control units respectively, forming a closed-loop feedback regulation mechanism to achieve efficient power control and system protection. When the residential energy storage system is in a charging state, the above energy conversion process is reversed: electrical energy is converted into AC power by the HV bus through the first rectifier-inverter circuit, and after being transmitted wirelessly through the first compensation network, it is converted into DC power by the second rectifier-inverter circuit, and finally charges the battery cell unit.

[0029] Each battery module unit in this invention is equipped with an independent bidirectional rectifier-inverter circuit and a BMS battery management system, achieving bidirectional energy transfer between the battery module and the HV bus via magnetic coupling. While enabling wireless energy transfer, electrical isolation is also achieved, thus confining faults to a single module unit, resulting in strong fault isolation. During maintenance, faulty module units can be directly replaced without system downtime, greatly improving system reliability and maintenance convenience. Furthermore, this architecture enables true plug-and-play expansion; adding new battery module units requires no hardware modifications or software reconfiguration of the existing system, significantly improving system flexibility and scalability.

[0030] It should be emphasized that the above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model in any way. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A wireless parallel battery module, comprising: It includes several battery module units connected in parallel to the HV bus, and each battery module unit includes a first module and a second module; The first module includes a first rectifier-inverter circuit and a first coil. The DC side of the first rectifier-inverter circuit is connected to the HV bus, and its AC side is connected to the first coil. The second module includes a cell unit, a battery management system, a second rectifier-inverter circuit, and a second coil. The DC side of the second rectifier-inverter circuit is connected to the cell unit, and its AC side is connected to the second coil. The first module and the second module achieve bidirectional mutual inductive coupling through the docking of the first coil and the second coil, forming a non-contact power transmission path; The first rectifier-inverter circuit is configured as follows: During charging, the high-voltage DC power from the HV bus is rectified and inverted into high-frequency AC power, which is then output through the first coil. During discharge, the high-frequency AC power from the first coil is rectified and inverted into high-voltage DC power and fed back to the HV bus. The second rectifier-inverter circuit is configured as follows: During discharge, the low-voltage DC power output from the battery cell unit is rectified and inverted into high-frequency AC power, and then output through the second coil; During charging, the high-frequency AC power from the second coil is rectified and inverted into low-voltage DC power to charge the battery cell unit; The battery management system is connected to the battery cell and the second rectifier-inverter circuit respectively, and is used to monitor and manage the working status of the battery cell and control the working status and power output of the second rectifier-inverter circuit.

2. The wireless parallel battery module of claim 1, wherein, The first module of each battery module unit is packaged to form an independent energy interface module, which is fixedly installed in the battery cabinet and electrically connected to the HV bus; the second module of each battery module unit is packaged to form an independent energy storage module, which is fixedly installed in a preset slot in the battery cabinet; the energy interface module is physically connected and fixed to the second coil of the energy storage module through the first coil.

3. The wireless parallel battery module of claim 1, wherein, The battery management system includes a power supply unit, an AFE acquisition unit, a charge / discharge control unit, a wireless communication unit, and a second main control unit; The power supply unit is connected to the AFE acquisition unit, the charge and discharge control unit, the wireless communication unit, and the second main control unit, respectively, and is configured to provide operating voltage to each unit. The second main control unit is connected to the AFE acquisition unit, the charge / discharge control unit, and the wireless communication unit respectively, and is configured to run control algorithms, process data, and coordinate the work of each unit; The AFE acquisition unit is connected to the cell unit and is configured to acquire signals from the cell unit and transmit the acquired signals to the second main control unit; The charge / discharge control unit is connected to the second main control unit and the battery cell unit respectively, and is configured to receive instructions from the second main control unit and control the battery cell unit to charge and discharge. The wireless communication unit is connected to the second main control unit and configured to communicate wirelessly with the external first main control unit.

4. The wireless parallel battery module of claim 3, wherein, The battery management system further includes a thermal management unit, which is connected to the second main control unit and the cell unit respectively, and is configured to perform heating or heat dissipation operations according to the instructions of the second main control unit.

5. The wireless parallel battery module of claim 3, wherein, The battery management system further includes a storage unit connected to the second main control unit and configured to store data from the AFE acquisition unit and data processed by the second main control unit.

6. The wireless parallel battery module of claim 3, wherein, The plurality of battery module units include a main battery module unit and at least one slave battery module unit; The main battery module unit communicates with the external first main control unit through its wireless communication unit, and is used to receive the control signal from the first main control unit and forward the control signal to the wireless communication unit of each of the slave battery module units. Each of the slave battery module units sends its own operating status information to the main battery module unit through its wireless communication unit; The main battery module unit is further configured to receive and summarize the operating status information and its own status information of each of the slave battery module units, and interact with the first main control unit.

7. The wireless parallel battery module of claim 3, wherein, The second main control unit is also configured as follows: Based on the data collected by the AFE acquisition unit, the state of charge (SOC) and state of health (SOH) of the battery cell are evaluated using a preset algorithm.

8. The wireless parallel battery module of claim 3, wherein, The second main control unit is also configured as follows: Real-time monitoring of the voltage and current of the battery cell unit; When the voltage or current exceeds a preset safety threshold, the charging and discharging control unit is controlled to perform a protection action.

9. The wireless parallel battery module of claim 1, wherein, It also includes a first inductor and a second inductor; a second compensation network is provided between the second rectifier-inverter circuit and the second inductor; a first compensation network is provided between the first rectifier-inverter circuit and the first inductor; the first compensation network and the second compensation network are used to adjust the circuit resonance characteristics.

10. The wireless parallel battery module of claim 1, wherein, It also includes a first driving circuit, a second driving circuit, a first main control unit, and a second main control unit; The first driving circuit is connected to the first main control unit and the first rectifier-inverter circuit respectively, and is used to receive control commands issued by the first main control unit and drive the power switching devices in the first rectifier-inverter circuit. The second drive circuit is connected to the second main control unit and the second rectifier-inverter circuit respectively, and is used to receive control commands issued by the second main control unit and drive the power switching devices in the second rectifier-inverter circuit.

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