Battery matching device

Abstract

The application relates to a battery matching device connected between an inverter and an externally connected battery, which comprises at least one of a pre-charge module with a function of inhibiting starting impact current of the battery, an auxiliary function module for providing an external auxiliary circuit for the battery, a protection module for providing a protection function, an auxiliary power supply module and a control module for realizing control and communication functions; the pre-charge module, the auxiliary function module and the protection module are connected on a power line between the battery and the inverter, the auxiliary power supply module is connected with the power line and the control module, the control module is connected with a control line between the battery and the inverter and is connected with the pre-charge module, the auxiliary function module and the protection module respectively. The application integrates additional functions required by mainstream batteries, has strong compatibility, is convenient to replace and can simplify the inverter and reduce the cost.

Description

Technical Field

[0001] This invention relates to the field of energy storage battery technology, and more specifically to a battery matching device for matching an inverter with its external battery. Background Technology

[0002] Currently, all outdoor energy storage inverters require an external battery for energy storage. The wiring diagram for the inverter and external battery is attached. Figure 1 As shown, the two are connected via two power lines (one positive and one negative) and a control line. Currently, there are many mainstream manufacturers and product models of residential energy storage batteries on the market. Products fall into two main categories: high-voltage batteries and ordinary batteries. Considering market trends, user needs, and system efficiency, high-voltage batteries are becoming increasingly common. Furthermore, to meet the diverse needs of different users, energy storage inverters are typically designed to accommodate multiple brands and models of batteries.

[0003] Currently, in the process of matching battery designs, some battery models have built-in soft-start functionality, while others do not; some batteries require external auxiliary circuits (such as large-capacity capacitors, enable circuits, FUSE, etc.), and so on. In order to meet these requirements at the same time, the design of energy storage inverters becomes more complex, with more internal components, excessive circuit redundancy, and a larger overall inverter size, ultimately leading to excessively high costs. Summary of the Invention

[0004] The purpose of this invention is to provide a battery matching device that simplifies the internal design of energy storage inverters, has strong compatibility, reduces costs, and facilitates battery replacement.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A battery matching device is connected between an inverter and an external battery. The battery matching device includes a pre-charge module that suppresses the starting inrush current of the battery, an auxiliary function module that provides external auxiliary circuitry for the battery, a protection module that provides protection, an auxiliary power supply module, and a control module for implementing at least one of the control functions and communication functions. The pre-charge module, the auxiliary function module, and the protection module are connected to the power line between the battery and the inverter. The auxiliary power supply module is connected to the power line and the control module. The control module is connected to the control line between the battery and the inverter, and is also connected to the pre-charge module, the auxiliary function module, and the protection module.

[0007] The pre-charge module includes:

[0008] A main circuit connected on the power line, two ends of the main circuit form two groups of terminals, each group of terminals includes a positive terminal and a negative terminal;

[0009] A sampling circuit connected with the two groups of terminals, for sampling the voltage of the two groups of terminals;

[0010] A bypass circuit connected on the power line in parallel, the bypass circuit is connected or disconnected based on a pre-charge control signal;

[0011] A pre-charge control circuit connected with the sampling circuit and the bypass circuit respectively, for outputting the pre-charge control signal based on the voltage of the two groups of terminals.

[0012] The main circuit includes a limiting resistor, a reverse connection protection diode and a capacitor, two positive terminals are connected and located on a positive power line, the limiting resistor and the reverse connection protection diode are connected in series between two negative terminals and located on a negative power line, and the capacitor is connected between the positive power line and the negative power line.

[0013] The bypass circuit includes a controllable power switching device and a switching circuit, the switching circuit is connected with the pre-charge control circuit and the control end of the controllable power switching device respectively, the switching circuit is connected or disconnected based on the pre-charge control signal, and the controllable power switching device is connected or disconnected based on the connection or disconnection of the switching circuit.

[0014] The protection module includes at least one of an overvoltage protection circuit, an overcurrent protection circuit and a temperature protection circuit.

[0015] The overvoltage protection circuit includes:

[0016] A detection circuit connected with the port of the inverter, for detecting the port voltage of the inverter;

[0017] A protection switch connected on the power line, the protection switch is connected or disconnected based on a drive signal;

[0018] A protection control circuit connected with the detection circuit and the control module, for outputting a protection control signal when the port voltage of the inverter exceeds a preset voltage threshold;

[0019] A drive circuit connected with the protection control circuit and the protection switch, for outputting the drive signal based on the protection control signal.

[0020] The overvoltage protection circuit further comprises a third resistor, a fourth resistor, a fifth resistor and a first capacitor, the source and the drain of the protection switch are connected to the positive power line, the third resistor, the fourth resistor and the first capacitor are connected in parallel between the positive power line and the negative power line, and the fifth resistor is connected to the driving circuit and the gate of the protection switch respectively.

[0021] The protection module further comprises an overcurrent protection circuit and / or a temperature protection circuit.

[0022] The auxiliary function module comprises a capacitor group connected in parallel to the power line and / or an enable circuit for outputting an enable signal to trigger the battery.

[0023] The enable circuit comprises an enable control circuit, a first enable switch tube and a second enable switch tube, the enable control circuit is connected to the control module, the base of the first enable switch tube is connected to the enable control circuit, the collector of the first enable switch tube is connected to the base of the second enable switch tube, the source of the first enable switch tube is grounded, the emitter of the second enable switch tube is connected to the working power supply, and the collector of the second enable switch tube is connected to the battery.

[0024] The enable circuit further comprises a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor and a second capacitor, the sixth resistor is connected to the base of the first enable switch tube and the enable control circuit respectively, the seventh resistor is connected to the base and the emitter of the first enable switch tube respectively, the eighth resistor is connected to the working power supply and the emitter of the second enable switch tube respectively, the ninth resistor is connected to the working power supply and the base of the second enable switch tube respectively, the tenth resistor is connected to the collector of the second enable switch tube and the ground respectively, and the second capacitor is connected to the base and the emitter of the first enable switch tube respectively.

[0025] The auxiliary power supply module comprises a power circuit connected to the power line, an SPS control circuit connected to the power circuit, a plurality of groups of transformers with the primary sides connected to the power circuit, and an output power supply circuit connected to the secondary sides of the transformers.

[0026] The battery matching device further comprises a reserved expansion module connected to the power line.

[0027] Thanks to the above technical solution, the present application has the following advantages compared with the prior art: the present application integrates the additional functions required by mainstream batteries, has strong compatibility, is convenient to replace, and thus can simplify the inverter involved and reduce the cost. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a schematic diagram of the connection between the existing inverter and the battery. Figure 1 Figure 2 is a schematic diagram of the connection between the existing inverter and the battery.

[0029] Figure 3 is a schematic diagram of the structure of the battery matching device of the present application. Figure 2 Figure 4 is a schematic diagram of the connection between the battery matching device of the present application and the battery.

[0030] Figure 5 is a circuit diagram of the pre-charge module in the battery matching device of the present application. Figure 3 Figure 6 is a circuit diagram of the protection module in the battery matching device of the present application.

[0031] Figure 7 is a circuit diagram of the auxiliary function module in the battery matching device of the present application. Figure 4 Figure 8 is a circuit diagram of the auxiliary power supply module in the battery matching device of the present application.

[0032] Figure 9 is a circuit diagram of the control module in the battery matching device of the present application. Figure 5 Figure 10 is a circuit diagram of the reserved expansion module in the battery matching device of the present application.

[0033] Figure 11 is a circuit diagram of the reserved expansion module in the battery matching device of the present application. Figure 6 Figure 12 is a circuit diagram of the reserved expansion module in the battery matching device of the present application. DETAILED DESCRIPTION

[0034] The present application will be further described below in conjunction with the embodiments shown in the accompanying drawings.

[0035] Embodiment 1: As shown in Figure 2, a battery matching device is connected between an inverter and an externally connected battery, and is connected to the power lines (including positive and negative power lines) and control lines between the inverter and the battery. Figure 2 The battery matching device includes at least one of a pre-charge module, an auxiliary function module, a protection module, and an auxiliary power supply module, and a control module, and can also include a reserved expansion module. The pre-charge module, the auxiliary function module, and the protection module are connected to the power lines between the battery and the inverter, the auxiliary power supply module is connected to the power lines and the control module, the control module is connected to the control lines between the battery and the inverter, and is connected to the pre-charge module, the auxiliary function module, and the protection module, respectively.

[0036] 1. Pre-charge module

[0037] The pre-charge module has the function of suppressing the starting impact current of the battery, specifically suppressing the starting impact current of the battery, preventing damage to circuit devices or triggering overcurrent protection devices, causing the starting to fail, and at the same time providing the battery with the anti-reverse connection function (reverse connection, the equipment is not damaged and the error information is reported through the inverter APP; after recovery, normal work).

[0038] Figure 3 is a schematic diagram of the structure of the battery matching device of the present application.

[0039] Figure 4 is a schematic diagram of the connection between the battery matching device of the present application and the battery. Figure 3As shown, the pre-charge module includes a main circuit, a sampling circuit, a bypass circuit and a pre-charge control circuit. The main circuit is connected to the power line, and two ends of the main circuit form two groups of terminals (one group is BAT IN+ and BAT IN-, and the other group is BAT OUT+ and BAT OUT-), each group of terminals includes a positive terminal (BAT IN+, BAT OUT+) and a negative terminal (BAT IN-, BAT OUT-), the terminals on the positive power line are positive terminals, and the terminals on the negative power line are negative terminals. The sampling circuit is connected to the two groups of terminals and is used to sample the voltages of the two groups of terminals. The bypass circuit is connected in parallel to the power line, and the bypass circuit is turned on or disconnected based on the pre-charge control signal. The pre-charge control circuit is connected to the sampling circuit and the bypass circuit, and is used to output the pre-charge control signal based on the voltages of the two groups of terminals.

[0040] Specifically, the main circuit includes a limiting resistor R3, a reverse connection protection diode D1 and a capacitor C1, the two positive terminals are connected and located on the positive power line, the limiting resistor R3 and the reverse connection protection diode D1 are connected in series between the two negative terminals and located on the negative power line, and the capacitor C1 is connected between the positive power line and the negative power line. The bypass circuit includes a controllable power switching device and a switching circuit, the switching circuit is connected to the pre-charge control circuit and the control end of the controllable power switching device, the switching circuit is turned on or disconnected based on the pre-charge control signal, and the controllable power switching device is turned on or disconnected based on the turning on or disconnection of the switching circuit. Specifically, the controllable power switching device Q1 (such as RELAY, MOS, etc. controlled device) is connected in parallel across the limiting resistor R3 and the reverse connection protection diode D1. The pre-charge control circuit is connected to the switching circuit which is turned on or disconnected based on the pre-charge control signal, and the switching circuit is connected to the control end of the controllable power switching device Q1. When the switching circuit is turned on or disconnected under the control of the pre-charge control signal output by the pre-charge control circuit, the controllable power switching device Q1 is further turned on or disconnected based on the on-off state of the switching circuit. The switching circuit includes a switching tube Q10, a first resistor R5 and a second resistor R6, one end of the first resistor R5 is connected to the pre-charge control circuit, the other end of the first resistor R5 is connected to the base of the switching tube Q10, the collector of the switching tube Q10 is connected to the power supply end of the controllable power switching device Q1, the emitter of the switching tube Q10 is grounded, and the second resistor R6 is connected between the base and the emitter of the switching tube Q10. The input end of the sampling circuit is connected to the four terminals through corresponding resistors R10-R13.

[0041] The basic working principle of the pre-charge module is that the pre-charge module voltage is sampled and compared, and when the voltage difference between the two ends is less than a certain value, the controllable power switching device of the bypass circuit is turned on, thereby reducing the normal working loss, wherein the limiting resistor R3 functions to limit the pre-charge circuit.

[0042] The sampling circuit can detect the voltage across the precharge module, which is the voltage across the controllable power switch Q1. When the device is first started, the controllable power switch Q1 is open, which reduces the inrush current of the line. When the device is operating stably, the controllable power switch Q1 is closed. Since the on-state impedance of the controllable power switch Q1 is very small, it reduces the loss during stable operation.

[0043] 2. Protection Module

[0044] The protection module provides protection for the battery, including at least one of overvoltage protection circuit, overcurrent protection circuit, and temperature protection circuit. The overvoltage protection circuit prevents abnormal high voltage from the inverter port from flowing back to the battery port and damaging the battery.

[0045] As attached Figure 4 As shown, the overvoltage protection circuit includes a detection circuit, a protection switch, a protection control circuit, and a drive circuit. The detection circuit is connected to the inverter's ports to detect the inverter's port voltage. The protection switch Q40 is connected to the power line; it is a controllable device or similar apparatus, and it is switched on or off based on a drive signal. The protection control circuit is connected to the detection circuit and the control module, and outputs a protection control signal when the inverter's port voltage exceeds a preset voltage threshold. The drive circuit is connected to the protection control circuit and the protection switch, and outputs a drive signal based on the protection control signal.

[0046] The overvoltage protection circuit also includes a third resistor R40, a fourth resistor R41, a fifth resistor R43, and a first capacitor C40. The source and drain of the protection switch Q40 are connected to the positive power line. The third resistor R40, the fourth resistor R41, and the first capacitor C40 are connected in parallel between the positive power line and the negative power line. The two ends of the fifth resistor R43 are connected to the drive circuit and the gate of the protection switch Q40, respectively. The third resistor R40 and the fourth resistor R41 are connected in parallel in the circuit to discharge charge; the first capacitor C40 filters and decouples the circuit; the fifth resistor R43 is a controllable device, namely the drive resistor of the protection switch Q40, which controls the switching speed of the controllable device.

[0047] The basic working principle of the overvoltage protection circuit is: the internal detection circuit monitors the voltage of the battery matching device port (i.e., the port output device - inverter) in real time. When any state of the inverter causes the port voltage to exceed the set voltage threshold, the internal protection switch Q40 is turned off to prevent high voltage backflow and damage to the battery.

[0048] 3. Auxiliary function modules

[0049] The auxiliary function module is used to provide external auxiliary circuit for the battery. Some models of the battery need to be connected with external devices to ensure normal operation, such as external large-capacity electrolytic capacitor, enable circuit and other auxiliary circuits. The auxiliary function module includes a capacitor group (large-capacity electrolytic capacitor) connected in parallel with the power line and / or an enable circuit for outputting an enable signal to trigger the action of the battery. As shown in the accompanying Figure 5 The auxiliary function module in the embodiment includes a capacitor group and an enable circuit.

[0050] The capacitor group includes a plurality of series and / or parallel capacitors connected between the positive power line and the negative power line. The capacitor group is connected in parallel with the power bus and is located after the pre-charge circuit. Generally, due to the capacitive load in the line and the initial state of the charge being zero, when an external voltage excitation source is suddenly applied, a large instantaneous impact current will be generated, thereby causing partial device failure and device function failure. The pre-charge current is to reduce the impact current in this case, which is equivalent to adding an impedance directly between the external excitation source and the capacitive load to limit the impact current, and therefore the capacitor group is located after the pre-charge circuit.

[0051] The enable circuit includes an enable control circuit, a first enable switch tube Q31 and a second enable switch tube Q30. The enable control circuit is connected with the control module, the base of the first enable switch tube Q31 is connected with the enable control circuit, the collector of the first enable switch tube Q31 is connected with the base of the second enable switch tube Q30, the source of the first enable switch tube Q31 is grounded, the emitter of the second enable switch tube Q31 is connected with the working power supply VCC, and the collector of the second enable switch tube Q31 is connected with the battery as an enable output end, thereby activating the battery. The enable circuit further includes a sixth resistor R35, a seventh resistor R34, an eighth resistor R30, a ninth resistor R31, a tenth resistor R32 and a second capacitor C36, which can control the on-off of the small signal switch and thereby control the output of the enable signal. The two ends of the sixth resistor R35 are respectively connected with the base of the first enable switch tube Q31 and the enable control circuit, the two ends of the seventh resistor R34 are respectively connected with the base and the emitter of the first enable switch tube Q31, the two ends of the eighth resistor R30 are respectively connected with the working power supply VCC and the emitter of the second enable switch tube Q30, the two ends of the ninth resistor R31 are respectively connected with the working power supply VCC and the base of the second enable switch tube Q30, the two ends of the tenth resistor R32 are respectively connected with the collector of the second enable switch tube Q30 and the ground, and the two ends of the second capacitor C36 are respectively connected with the base and the emitter of the first enable switch tube Q31.

[0052] 4. Auxiliary power supply module

[0053] The auxiliary power supply module is used to provide stable working power supply for each module inside the device.

[0054] As attached Figure 6 As shown, the auxiliary power supply module includes a power circuit, an SPS control circuit, multiple transformers T50, and an output power supply circuit. The power circuit is connected to the power lines, and a capacitor C50 is connected between the positive and negative power lines. The SPS control circuit is connected to the power circuit. The primary winding of the multiple transformers T50 is connected to the power circuit, and the output power supply circuit is connected to the secondary winding of the transformers.

[0055] The basic working principle of the auxiliary power supply module is: through internal isolation power supply, it generates 12V, 5V and other working power supplies to provide power to each module in each system.

[0056] 5. Control Module

[0057] The control module is used to implement control and communication functions, specifically including: executing control actions of individual modules; communication interfaces between modules; and coordinated communication between the battery, battery matching device, and inverter equipment.

[0058] 6. Extension Module

[0059] The reserved expansion module is connected to the power line and can be connected in series between the auxiliary function module and the protection module.

[0060] The aforementioned battery matching device can be externally mounted, integrating additional functions required by mainstream batteries, offering strong compatibility and easy replacement. This solution simplifies the internal design of energy storage inverters, enabling the inverter to match most batteries without the battery matching device; other battery models with special requirements are used in conjunction with this matching device. The device's functionality is expandable to meet future needs. Each functional module in the solution executes independently, facilitating expansion and stacking, and can adaptively select the corresponding functional module based on external battery functions to achieve full matching.

[0061] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A battery matching device connected between an inverter and a battery externally connected thereto, characterized by comprising: a battery matching unit configured to match the battery to the inverter; and a battery matching control unit configured to control the battery matching unit. The battery matching device comprises a pre-charging module having a function of suppressing a starting impact current of the battery, an auxiliary function module for providing an external auxiliary circuit for the battery, a protection module for providing a protection function, an auxiliary power supply module, and a control module for realizing control and communication functions; the pre-charging module, the auxiliary function module, and the protection module are connected on a power line between the battery and the inverter, the auxiliary power supply module is connected with the power line and the control module, the control module is connected with a control line between the battery and the inverter, and is connected with the pre-charging module, the auxiliary function module, and the protection module respectively; The pre-charging module comprises: a main circuit connected on the power line, two ends of the main circuit forming two groups of terminals, each group of the terminals comprising a positive terminal and a negative terminal; a sampling circuit connected with the two groups of terminals for sampling voltages of the two groups of terminals; a bypass circuit connected on the power line in bypass, the bypass circuit being connected or disconnected based on a pre-charging control signal; a pre-charging control circuit connected with the sampling circuit and the bypass circuit respectively for outputting the pre-charging control signal based on the voltages of the two groups of terminals; the main circuit comprising a limiting resistor, a reverse connection protection diode, and a capacitor, two positive terminals being connected and located on a positive power line, the limiting resistor and the reverse connection protection diode being connected in series between two negative terminals and located on a negative power line, and the capacitor being connected between the positive power line and the negative power line; the bypass circuit comprising a controllable power switching device and a switching circuit, the switching circuit being connected with the pre-charging control circuit and a control end of the controllable power switching device respectively, the switching circuit being connected or disconnected based on the pre-charging control signal, and the controllable power switching device being connected or disconnected based on the connection or disconnection of the switching circuit; the pre-charging module being sampled for voltage comparison, and when a voltage difference is less than a certain value, the controllable power switching device of the bypass circuit is connected; the control and communication functions realized by the control module comprising: performing a control action of a single module; communicating and interfacing between modules; cooperating communication between the battery, the battery matching device, and the inverter equipment; when reversed, reporting error information through an inverter APP; The battery matching device further comprises a reserved expansion module connected on the power line.

2. The battery matching apparatus of claim 1, wherein: The protection module comprises at least one of an overvoltage protection circuit, an overcurrent protection circuit, and a temperature protection circuit.

3. The battery matching apparatus of claim 2, wherein: The overvoltage protection circuit comprises: a detection circuit connected with a port of the inverter for detecting a port voltage of the inverter; a protection switch connected on the power line, the protection switch being connected or disconnected based on a driving signal; a protection control circuit connected with the detection circuit and the control module for outputting a protection control signal when the port voltage of the inverter exceeds a preset voltage threshold. A driving circuit connected with the protection control circuit and the protection switch, configured to output the driving signal based on the protection control signal.

4. The battery matching apparatus of claim 3, wherein: The overvoltage protection circuit further comprises a third resistor, a fourth resistor, a fifth resistor and a first capacitor, the source and the drain of the protection switch are connected to the positive power line, the third resistor, the fourth resistor and the first capacitor are connected in parallel between the positive power line and the negative power line, and the fifth resistor is connected with the driving circuit and the gate of the protection switch respectively.

5. The battery matching apparatus of claim 1, wherein: The auxiliary function module comprises a capacitor group connected in parallel with the power line and / or an enable circuit configured to output an enable signal to trigger the battery.

6. The battery matching apparatus of claim 5, wherein: The enable circuit comprises an enable control circuit, a first enable switch tube and a second enable switch tube, the enable control circuit is connected with the control module, the base of the first enable switch tube is connected with the enable control circuit, the collector of the first enable switch tube is connected with the base of the second enable switch tube, the source of the first enable switch tube is grounded, the emitter of the second enable switch tube is connected with a working power supply, and the collector of the second enable switch tube is connected with the battery.

7. The battery matching apparatus of claim 6, wherein: The enable circuit further comprises a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor and a second capacitor, the sixth resistor is connected with the base of the first enable switch tube and the enable control circuit respectively, the seventh resistor is connected with the base and the emitter of the first enable switch tube respectively, the eighth resistor is connected with the working power supply and the emitter of the second enable switch tube respectively, the ninth resistor is connected with the working power supply and the base of the second enable switch tube respectively, the tenth resistor is connected with the collector of the second enable switch tube and the ground respectively, and the second capacitor is connected with the base and the emitter of the first enable switch tube respectively.

8. The battery matching apparatus of claim 1, wherein: The auxiliary power supply module comprises a power circuit connected with the power line, an SPS control circuit connected with the power circuit, a plurality of groups of transformers with the primary sides connected with the power circuit, and an output power supply circuit connected with the secondary sides of the transformers.

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