WO2024044999A1

WO2024044999A1 - Auxiliary power source for energy storage system

Info

Publication number: WO2024044999A1
Application number: PCT/CN2022/116023
Authority: WO
Inventors: 任玉伟; 聂洪涛; 王大庆
Original assignee: 深圳市富兰瓦时技术有限公司
Priority date: 2022-08-31
Filing date: 2022-08-31
Publication date: 2024-03-07
Also published as: WO2024044999A9; CN219287376U

Abstract

An auxiliary power source for an energy storage system. The auxiliary power source comprises: a resonant circuit module (110), comprising a first power supply input end (IN1), a second power supply input end (IN2), a first power supply output end (OUT1) and a second power supply output end (OUT2), wherein the resonant circuit module (110) operates in an open-loop mode, and converts a direct-current bus voltage into a secondary output voltage; and a flyback power source module (120), comprising a third power supply input end (IN3), a fourth power supply input end (IN4), a fifth power supply input end (IN5), a sixth power supply input end (IN6) and a power supply output end (VOUT), wherein the flyback power source module (120) operates in a closed-loop operating mode, and converts the voltage of an energy storage battery (130) and/or the secondary output voltage of the resonant circuit module (110) into an auxiliary power source output voltage.

Description

Energy storage system auxiliary power supply

Technical field

This application relates to the field of energy storage technology, for example, to an auxiliary power supply for an energy storage system.

Background technique

The energy crisis and environmental pollution are becoming increasingly serious. The realization of the strategic goals of carbon neutrality and carbon peaking is inseparable from the larger-scale use of new energy. With the large-scale installed capacity of new energy sources such as wind and solar energy, the consumption of new energy sources is inseparable from energy storage.

The auxiliary power supply of the energy storage system in related technologies generally adopts a solution of setting two flyback power supplies on the battery side and AC side or a solution of setting two flyback power supplies on the battery side and DC side. Both auxiliary sources are under closed-loop control. When the energy storage system is in standby, both auxiliary sources will be put into work, resulting in a large standby power consumption of the energy storage system, resulting in a waste of energy.

Contents of the invention

This application provides an auxiliary power supply for an energy storage system to avoid energy waste due to large standby power consumption of the energy storage system.

This application provides an auxiliary power supply for an energy storage system, including:

The resonant circuit module includes a first power supply input terminal, a second power supply input terminal, a first power supply output terminal and a second power supply output terminal; the first power supply input terminal and the second power supply input terminal are respectively connected to the DC bus. Positive voltage and negative voltage; the resonant circuit module works in an open-loop mode, converting the DC bus voltage into a secondary output voltage. The positive voltage and negative voltage of the secondary output voltage pass through the first power supply output terminal and the second power supply output respectively. terminal output;

A flyback power supply module includes a third power supply input terminal, a fourth power supply input terminal, a fifth power supply input terminal, a sixth power supply input terminal and a power supply output terminal; the third power supply input terminal and the fourth power supply input terminal are respectively The positive voltage and negative voltage of the energy storage battery are connected, and the fifth power supply input terminal and the sixth power supply input terminal are respectively connected to the first power supply output terminal and the second power supply output of the resonant circuit module. end; the flyback power module operates in a closed-loop control mode, converting at least one of the voltage of the energy storage battery and the secondary output voltage of the resonant circuit module into an auxiliary power output voltage.

Description of drawings

Figure 1 is a schematic diagram of the hardware framework of an auxiliary power supply for an energy storage system provided by an embodiment of the present application;

Figure 2 is a schematic diagram of the hardware structure of a flyback power module of an auxiliary power supply for an energy storage system provided by an embodiment of the present application;

Figure 3 is a circuit schematic diagram of the first input unit of the flyback power module provided by the embodiment of the present application;

Figure 4 is a circuit schematic diagram of the first controller power supply unit of the flyback power module provided by the embodiment of the present application;

Figure 5 is a circuit schematic diagram of the first secondary circuit unit of the flyback power module provided by the embodiment of the present application;

Figure 6 is a schematic diagram of the hardware structure of a resonant circuit module of an auxiliary power supply for an energy storage system provided by an embodiment of the present application;

Figure 7 is a circuit schematic diagram of the second input unit of the resonant circuit module provided by the embodiment of the present application;

Figure 8 is a circuit schematic diagram of the second controller power supply unit of the resonant circuit module provided by the embodiment of the present application;

Figure 9 is a circuit schematic diagram of the primary circuit unit of the resonant circuit module provided by the embodiment of the present application;

Figure 10 is a circuit schematic diagram of the second secondary circuit unit of the resonant circuit module provided by the embodiment of the present application;

Figure 11 is a schematic circuit diagram of an auxiliary power supply for an energy storage system provided by an embodiment of the present application.

Detailed ways

It should be noted that the terms "first", "second", etc. in the description and claims of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances so that the embodiments of the application described herein can be practiced in sequences other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, e.g., a process, method, system, product, or apparatus that encompasses a series of steps or units and need not be limited to those explicitly listed. Those steps or elements may instead include other steps or elements not expressly listed or inherent to the process, method, product or apparatus.

Figure 1 is a schematic diagram of the hardware framework of an auxiliary power supply for an energy storage system provided by an embodiment of the present application. Referring to Figure 1, the auxiliary power supply of the energy storage system includes:

The resonant circuit module 110 includes a first power supply input terminal IN1, a second power supply input terminal IN2, a first power supply output terminal OUT1 and a second power supply output terminal OUT2; the first power supply input terminal IN1 and the second power supply input terminal IN2 are connected respectively. The positive voltage and negative voltage of the DC bus; the resonant circuit module works in open-loop mode and converts the DC bus voltage into the secondary output voltage. The positive voltage and negative voltage of the secondary output voltage pass through the first power supply output terminal OUT1 and the second power supply output terminal OUT1 respectively. Power supply output terminal OUT2 output;

The flyback power module 120 includes a third power supply input terminal IN3, a fourth power supply input terminal IN4, a fifth power supply input terminal IN5, a sixth power supply input terminal IN6 and a power supply output terminal VOUT; the third power supply input terminal IN3 and the fourth power supply input terminal IN3 The input terminal IN4 is respectively connected to the positive voltage and the negative voltage of the energy storage battery 130, and the fifth power supply input terminal IN5 and the sixth power supply input terminal IN6 are respectively connected to the first power supply output terminal OUT1 and the second power supply output terminal of the resonant circuit module 110. OUT2; the flyback power module 120 operates in a closed-loop control mode, converting the voltage of the energy storage battery 130 and/or the secondary output voltage of the resonant circuit module 110 into the auxiliary power output voltage.

For example, the auxiliary power supply of the energy storage system has two working modes: off-grid mode and grid-connected mode. In the off-grid mode, when the control unit of the energy storage system detects that the energy storage system needs to intervene, the resonant circuit module 110 cannot operate normally due to insufficient voltage on the DC bus of the energy storage system, and thus cannot provide the flyback power module 120 Provide power. In this state, the power supply of the flyback power module 120 comes entirely from the energy storage battery 130, and the flyback power module 120 converts the voltage output by the energy storage battery 130 into the auxiliary power output voltage. When the energy storage battery starts to supply power to the DC bus, the energy storage battery 130 supplies power to the DC bus through the main power circuit, thereby increasing the DC bus voltage to a predetermined voltage. After the DC bus voltage rises to a predetermined voltage, the resonant circuit module 110 begins to intervene, converting the DC bus voltage into a secondary output voltage and providing power to the flyback power module 120 . Moreover, the flyback power module 120 of the energy storage system works in the closed-loop control mode. The flyback power module 120 monitors the voltage value of the auxiliary power output voltage in real time, and adjusts the auxiliary power output voltage through feedback of the voltage value to achieve auxiliary power. Stable output of power supply output voltage.

In the off-grid mode, when the energy storage system is in the standby state, since the energy storage system is not involved in the work at this time, the voltage on the DC bus is insufficient, and the resonant circuit module 110 cannot work normally, and thus the flyback power module 120 cannot operate. powered by. At this time, the power supply of the flyback power module 120 comes entirely from the energy storage battery 130 . In this state, the auxiliary power output voltage output by the flyback power module 120 is only used to supply power to the control unit of the energy storage system to maintain the operation of the control unit. Since the auxiliary power output voltage output by the flyback power module 120 is only used to supply power to the control unit of the energy storage system, the main power circuit of the energy storage system does not work, and the voltage of the DC bus is still insufficient to maintain the normal operation of the resonant circuit module 110. Therefore, the resonant circuit module 110 does not consume power. In this way, the energy storage system reduces power consumption in standby mode.

In the grid-connected mode, when the energy storage battery 130 of the energy storage system is under-voltage, the energy storage battery 130 cannot supply power to the flyback power module 120. Therefore, the power supply of the flyback power module 120 comes entirely from the DC bus. The voltage of the DC bus rises to a predetermined voltage through the soft start circuit. After the DC bus voltage rises to a predetermined voltage, the resonant circuit module 110 begins to intervene, converting the DC bus voltage into a secondary output voltage and providing power to the flyback power module 120 .

The auxiliary power supply of the energy storage system in the embodiment of the present application adopts a two-circuit power supply design with closed-loop control of the flyback power module 120 and open-loop control of the resonant circuit module 110. In the off-grid mode, when the control unit of the energy storage system detects the need for energy storage When the system is involved in the work, the energy storage system uses the energy storage battery 130 to provide power to maintain the normal operation of the energy storage system; in the grid-connected mode, when the energy storage battery 130 of the energy storage system is under voltage, the energy storage system uses power supply from the grid. method to maintain the normal operation of the energy storage system. The design of the two-circuit power supply of the auxiliary power supply of the energy storage system ensures continuous power supply to the energy storage system. In addition, when the energy storage system is in the standby state in the off-grid mode, the power supply source of the control unit of the energy storage system is only the energy storage battery 130, and the resonant circuit module 110 does not work, which reduces the energy storage capacity in the standby state. System power consumption to avoid energy waste.

For example, the resonant circuit module 110 includes an asymmetric half-bridge structure or a symmetric half-bridge structure; the flyback power module includes a single-tube flyback structure or a dual-tube flyback structure.

For example, both the symmetrical half-bridge resonant circuit and the asymmetrical half-bridge resonant circuit have fewer switching tubes, which can reduce the pressure on the primary side components. The single-tube flyback structure has a switching tube and a transformer. The single-tube flyback has the characteristics of low standby power consumption and low use cost. The two-tube flyback structure has two switching tubes and two transformers. The double-tube flyback has the characteristics of low energy loss and high reliability. It should be noted that this embodiment does not limit the resonant circuit structure and flyback structure of the resonant circuit module 110. The structures of the resonant circuit module 110 and the flyback power supply module 120 will be described in detail below.

Figure 2 is a schematic diagram of the hardware structure of a flyback power module of an auxiliary power supply for an energy storage system provided by an embodiment of the present application. Referring to Figure 2, the flyback power module 110 includes: a first input unit 210, a first pulse width modulation (Pulse Width Modulation, PWM) controller 220, a first controller power supply unit 230, a switch unit 240, and a first transformer 250 , the first secondary circuit unit 260 and the feedback compensation unit 270; the first transformer 250 includes a first primary coil 251, a first secondary coil 252 and a second secondary coil 253;

The first terminal DK1 of the first input unit 210 serves as the third power supply input terminal IN3, the second terminal DK2 of the first input unit 210 serves as the fourth power supply input terminal IN4, and the third terminal DK3 of the first input unit 210 serves as the fifth power supply input terminal IN3. The input terminal IN5 and the fourth terminal DK4 of the first input unit 210 serve as the sixth power supply input terminal IN6; the fifth terminal DK5 of the first input unit 210 is electrically connected to the first terminal of the first primary coil 251. The first input unit 210 The sixth terminal DK6 is grounded; the first input unit 210 is configured to stabilize the input voltage;

The first terminal GD11 of the first controller power supply unit 230 is electrically connected to the fifth terminal DK5 of the first input unit 210 , and the second terminal GD12 of the first controller power supply unit 230 is electrically connected to the first terminal of the first secondary coil 252 connection, the third end GD13 of the first controller power supply unit 230 is electrically connected to the second end of the first secondary coil 252, the first end of the first secondary coil 252 is grounded; the fourth end of the first controller power supply unit 230 Terminal GD14 is electrically connected to the first PWM controller 220, and the first controller power supply unit 230 is configured to provide power to the first PWM controller 220;

The first terminal KG11 of the switch unit 240 is electrically connected to the second terminal of the first primary coil 251, the second terminal KG12 of the switch unit 240 is grounded, and the control terminal KZ of the switch unit 240 is electrically connected to the first PWM controller 220. The switch unit 240 is configured to turn on or off the first primary coil 251 branch in response to the control of the first PWM controller 220;

The first terminal CJ11 of the first secondary circuit unit 260 is electrically connected to the first terminal of the second secondary coil 253, and the second terminal CJ12 of the first secondary circuit unit 260 is electrically connected to the second terminal of the second secondary coil 253. connection, the third terminal of the first secondary circuit unit 260 serves as the power output terminal, and the fourth terminal of the secondary circuit is grounded; the first secondary circuit unit 260 is configured to induce electromagnetic changes in the first primary coil 251 to generate auxiliary power. The output voltage;

The first terminal FK1 of the feedback compensation unit 270 is electrically connected to the power output terminal VOUT, and the second terminal FK2 of the feedback compensation unit 270 is electrically connected to the first PWM controller 220. The first PWM controller 220 adjusts based on the feedback from the feedback compensation unit 270. Generate control signals.

For example, the flyback power module 120 is configured to convert the voltage of the energy storage battery 130 and/or the secondary output voltage of the resonant circuit module 110 into an auxiliary power output voltage. The power supply of the flyback power module 120 comes from the first input unit 210 . The first input unit 210 integrates the output voltage of the energy storage battery 130 and/or the secondary output voltage of the resonant circuit module 110 and outputs it to the first controller power supply unit 230 and the first transformer 250 . The first controller power supply unit 230 outputs the voltage of the first input unit 210 to the first PWM controller 220 . When the first PWM controller 220 operates, it sends a control signal to the switch unit 240, and the switch unit 240 turns on and off the first primary coil 251 of the first transformer 250 according to the control instructions of the first PWM controller 220. When the switch unit 240 is turned on, the first primary coil 251 of the first transformer 250 continuously stores energy; when the switch unit 240 is turned off, the inductive energy stored in the first primary coil 251 is released to other secondary coils of the first transformer 250 . The first secondary coil 252 of the first transformer 250 receives the energy conducted by the first primary coil 251 , and the first secondary coil 252 converts the energy into electrical energy and transmits it to the first PWM controller 220 through the first controller power supply unit 230 . The second secondary coil 253 of the first transformer 250 receives the energy of the first primary coil 251. The first secondary coil 252 converts the energy into electrical energy and transmits it to the first secondary circuit unit 260. The first secondary circuit unit 260 passes The power output terminal VOUT is output to the control unit of the energy storage system. The feedback compensation unit 270 is configured to monitor the output voltage of the power output terminal VOUT of the first secondary circuit unit 260 and feedback the output voltage to the first PWM controller 220. The first PWM controller 220 adjusts the switch according to the feedback voltage. The switching frequency of voltage 240 is adjusted to adjust the output voltage of the power output terminal VOUT of the first secondary circuit unit to achieve a stable output of the auxiliary power supply output voltage.

FIG. 3 is a schematic circuit diagram of the first input unit of the flyback power module provided by the embodiment of the present application. Referring to Figure 3, the first input unit 210 includes: a first diode D1, a second diode D2, a third diode D3, a fourth diode D4 and a first capacitor C1;

The anode of the first diode D1 is connected to the positive voltage of the energy storage battery 130, and the cathode of the first diode D2 is used as the fifth terminal DK5 of the first input unit;

The anode of the second diode D2 is connected to the positive voltage of the secondary output voltage, and the cathode of the second diode D2 is electrically connected to the cathode of the first diode D1;

The cathode of the third diode D3 is connected to the negative voltage of the energy storage battery 130, and the anode of the third diode D3 is connected to the ground;

The cathode of the fourth diode D4 is connected to the negative voltage of the secondary output voltage, and the anode of the fourth diode D4 is connected to the ground;

The first terminal of the first capacitor C1 is electrically connected to the cathode of the first diode D1, and the second terminal of the first capacitor C1 is grounded.

For example, with reference to Figures 1 and 3, when the auxiliary power supply of the energy storage system is powered by the secondary output voltage of the energy storage battery 130 and the resonant circuit module 110, the first input unit 210 is set to convert the output voltage of the energy storage battery 130 And/or the secondary output voltage of the resonant circuit module 110 is integrated and output to the first controller power supply unit 230 and the first transformer 250 . It should be noted that since the secondary output voltage of the resonant circuit module 110 is converted from the voltage of the DC bus, the secondary output voltage of the resonant circuit module 110 is affected by the DC bus voltage. When the DC bus voltage changes, the resonance The secondary output voltage of the circuit module 110 will also change, so the first input unit 210 needs to be provided to integrate the input voltage. For example, when the secondary output voltage of the resonant circuit module 110 changes, the secondary output voltage of the resonant circuit module 110 is inconsistent with the output voltage of the energy storage battery 130, causing the voltages of the two inputs of the first input unit 210 to be inconsistent and the voltage to be high. One path will flow to the path with lower voltage. To prevent this situation from happening, a diode D1, a second diode D2, a third diode D3 and a fourth diode D4 are set up in the circuit to prevent reverse current. . The input of the flyback power module 120 requires a stable voltage, so the first capacitor C1 is set in the first input unit 210 to stabilize the output voltage of the first input unit 210 .

The first input unit 210 in the embodiment of the present application consists of a first diode D1, a second diode D2, a third diode D3, a fourth diode D4 and a first capacitor C1, and is conducted through one-way conduction of the diodes. The characteristic prevents the secondary output voltage of the resonant circuit module 110 from affecting the two inputs, and utilizes the characteristic that the capacitor voltage cannot suddenly change to achieve a stable output voltage.

FIG. 4 is a circuit schematic diagram of the first controller power supply unit of the flyback power module provided by the embodiment of the present application. Referring to Figure 4, the first controller power supply unit 230 includes: a first resistor R1, a second resistor R2, a third resistor R3, a second capacitor C2 and a fifth diode D5; the first resistor R1 and the second resistor R2 is connected in series between the first terminal GD11 and the fourth terminal GD14 of the first controller power supply unit 230; the fifth diode D5 and the third resistor R3 are connected in series between the third terminal GD13 and the fourth terminal of the first controller power supply unit 230. between the terminals GD14; the first terminal of the second capacitor C2 is electrically connected to the fourth terminal GD14 of the first controller power supply unit 230, and the second terminal of the second capacitor C2 is grounded.

For example, the first controller power supply unit 230 is configured to power the first PWM controller 220 . The first resistor R1 and the second resistor R2 of the first controller power supply unit 230 are used to reduce the output voltage of the fourth terminal GD14 of the first controller power supply unit 230 . The fourth terminal GD14 of the first controller power supply unit 230 and the first PWM controller 220. Since the input voltage of the first PWM controller 220 is relatively small, a voltage dividing resistor needs to be set when powering the first PWM controller 220. to reduce the input voltage. The second capacitor C2, the third resistor R3, the fifth diode D5 of the first controller power supply unit 230 and the first secondary coil 252 of the first transformer 250 together form another power input of the first controller power supply unit 230. , the source of this power source is the induced voltage of the first secondary coil 252. Since the induced voltage of the first secondary coil 252 is AC, the fifth diode D5 is provided for rectification to convert the induced AC voltage into a DC voltage. The second capacitor C2 is a decoupling capacitor to prevent the voltage of the first terminal GD11 of the first controller power supply unit 230 from charging the first secondary coil 252 through the second terminal GD12 of the first controller power supply unit 230 to generate a magnetic field.

FIG. 5 is a circuit schematic diagram of the first secondary circuit unit of the flyback power module provided by the embodiment of the present application. Referring to Figure 5, the first secondary circuit unit 260 includes: a sixth diode D6 and a third capacitor C3; the anode of the sixth diode D6 is electrically connected to the second terminal CJ12 of the first secondary circuit unit 260, The cathode of the sixth diode D6 is electrically connected to the power output terminal VOUT; the first terminal of the third capacitor C3 is electrically connected to the power output terminal VOUT, and the second terminal of the third capacitor C3 is electrically connected to the first terminal of the first secondary circuit unit 260. Two-terminal electrical CJ12 connection.

For example, the first secondary circuit unit 260 is configured to induce electromagnetic changes in the first primary coil 251 to generate the auxiliary power output voltage. Since the voltage sensed by the first secondary circuit unit 260 is AC, the sixth diode D6 is provided for rectification. When the induced voltage of the first primary coil 251 is higher than the voltage on both sides of the capacitor, the capacitor C3 is charged; when the induced voltage of the first primary coil 251 is lower than the voltage on both sides of the capacitor, the capacitor C3 is discharged. Therefore, the third capacitor C3 is provided to stabilize the voltage output.

Figure 6 is a schematic diagram of the hardware structure of a resonant circuit module of an auxiliary power supply for an energy storage system provided by an embodiment of the present application. Referring to FIG. 6 , the resonant circuit module 110 includes: a second input unit 310 , a second PWM controller 330 , a second controller power supply unit 320 , a driver 340 , a primary circuit unit 350 , a second transformer 360 and a second secondary circuit unit. 370; The second transformer 360 includes a second primary coil 361, a third secondary coil 362 and a fourth secondary coil 363. The second end of the third secondary coil 362 is electrically connected to the first end of the fourth secondary coil 363. .

The first terminal DK7 of the second input unit 310 serves as the first power supply input terminal IN1, and the second terminal DK8 of the second input unit 310 serves as the second power supply input terminal IN2; the third terminal DK9 of the second input unit 310 is connected to the primary circuit unit The first terminal of 350 is electrically connected, and the fourth terminal DK9 of the second input unit 310 is electrically connected to the second terminal of the primary circuit unit 350; the second input unit 310 is configured to stabilize the input voltage.

The first terminal GD21 of the second controller power supply unit 320 is electrically connected to the third terminal DK9 of the second input unit 310, and the second terminal GD22 of the second controller power supply unit 320 is electrically connected to the fourth terminal DK10 of the second input unit 310. connection, the third terminal DK9 of the second controller power supply unit 320 is electrically connected to the second PWM controller 330; the second controller power supply unit 320 is configured to supply power to the second PWM controller 330.

The driver 340 is connected between the second PWM controller 330 and the control terminal KZ1 of the primary circuit unit 350, and the driver 340 is configured to control the primary circuit unit 350 in response to the control of the second PWM controller 340.

The third terminal CJDL3 of the primary circuit unit 350 is electrically connected to the first terminal of the second primary coil 361, and the fourth terminal CJDL4 of the primary circuit unit 350 is electrically connected to the second terminal of the second primary coil 361; the primary circuit unit 350 is configured as In response to the control of the driver 340, the branch of the second primary coil 361 is turned on or off.

The first terminal CJ21 of the second secondary circuit unit 370 is electrically connected to the first terminal of the third secondary coil 362, and the second terminal CJ22 of the second secondary circuit unit 370 is electrically connected to the second terminal of the fourth secondary coil 363. connection, the third terminal CJ23 of the second secondary circuit unit 370 serves as the first power supply output terminal OUT1, and the first terminal of the fourth secondary coil 363 serves as the second power supply output terminal OUT2; the second secondary circuit unit 370 is set as an induction The electromagnetic changes in the second primary coil 361 generate a secondary output voltage.

For example, with reference to Figures 1 and 6, the resonant circuit module 110 is configured to convert the DC bus voltage into a secondary output voltage. The power supply of the resonant circuit module 110 comes from the second input unit 310 . The second input unit 310 stabilizes the voltage input by the DC bus and outputs it to the second controller power supply unit 320 and the primary circuit unit 350 . The second controller power supply unit 320 outputs the voltage of the second input unit 310 to the second PWM controller 330 . When the second PWM controller 330 is working, it sends a control signal to the driver 340, and the driver 340 controls the on and off of the primary circuit unit 350 according to the control instructions of the second PWM controller 330. It should be noted that the on-off frequency of the primary circuit unit 350 is set at the resonant frequency point. When the primary circuit unit 350 is turned on, the second primary coil 361 of the second transformer 360 continuously stores energy; when the primary circuit unit 350 is turned off, the third secondary coil 362 and the fourth secondary coil 363 of the second transformer 360 receive energy. The energy conducted by the second primary coil 361 is converted into electrical energy by the third secondary coil 362 and the fourth secondary coil 363 and transmitted to the first input unit 210 of the flyback power module 130 through the second secondary circuit unit 370 . The first controller power supply unit 230 outputs the voltage of the first input unit 210 to the first PWM controller 220 . When the first PWM controller 220 operates, it sends a control signal to the switch unit 240, and the switch unit 240 turns on and off the first primary coil 251 of the first transformer 250 according to the control instructions of the first PWM controller 220. When the switch unit 240 is turned on, the first primary coil 251 of the first transformer 250 continuously stores energy; when the switch unit 240 is turned off, the inductive energy stored in the first primary coil 251 is released to other coils of the first transformer 250 . The first secondary coil 252 of the first transformer 250 receives the energy conducted by the first primary coil 251 , and the first secondary coil 252 converts the energy into electrical energy and transmits it to the first PWM controller 220 through the first controller power supply unit 230 . The second secondary coil 2523 of the first transformer 250 receives the energy of the first primary coil 251. The first secondary coil 252 converts the energy into electrical energy and transmits it to the first secondary circuit unit 260. The first secondary circuit unit 260 passes The power output terminal VOUT is output to the control unit of the energy storage system. The feedback compensation unit 270 is configured to monitor the output voltage of the power output terminal VOUT of the first secondary circuit unit 260 and feedback the output voltage to the first PWM controller 220. The first PWM controller 220 adjusts the switch according to the feedback voltage. The switching frequency of voltage 240 is adjusted to adjust the output voltage of the power output terminal VOUT of the first secondary circuit unit to achieve a stable output of the auxiliary power supply output voltage.

For example, the second PWM controller 330 and the first PWM controller 220 have the same model.

For example, the first PWM controller 220 in the resonant circuit module 110 and the second PWM controller 330 in the flyback power module 120 are of the same model. This setting reduces the difficulty of development and design and the cost of energy storage systems.

FIG. 7 is a schematic circuit diagram of the second input unit of the resonant circuit module provided by the embodiment of the present application. FIG. 8 is a schematic circuit diagram of the second controller power supply unit of the resonant circuit module provided by the embodiment of the present application. Referring to Figure 7, the second input unit 310 includes: a seventh diode D7 and a fourth capacitor C4; the anode of the seventh diode D7 is connected to the positive voltage of the DC bus, and the cathode of the seventh diode D7 serves as the third capacitor. The third terminal DK9 of the second input unit 310; the first terminal of the fourth capacitor C4 is electrically connected to the cathode of the seventh diode D7; the second terminal of the fourth capacitor C4 is connected to the negative voltage of the DC bus and serves as the second The fourth terminal DK10 of the input unit 310;

Referring to Figure 8, the second controller power supply unit 320 includes: a buck controller 321, an eighth diode D8, a first inductor L1 and a fifth capacitor C5; the first terminal of the buck controller 321 and the second controller The first terminal GD21 of the power supply unit 320 is electrically connected, the second terminal of the buck controller 321 is electrically connected to the second terminal GD22 of the second controller power supply unit 320, and the third terminal of the buck controller 321 is connected to the first inductor L1 The first end is electrically connected;

The second end of the first inductor L1 serves as the third end GD23 of the second controller power supply unit 320. The anode of the eighth diode D8 is electrically connected to the second end of the buck controller 321. The eighth diode D8 The cathode is electrically connected to the third terminal of the buck controller 321, the first terminal of the fifth capacitor C5 is electrically connected to the second terminal of the first inductor L1, and the second terminal of the fifth capacitor C5 is electrically connected to the third terminal of the buck controller 321. Three-terminal electrical connection.

For example, with reference to Figures 1, 7 and 8, the power supply source of the resonant circuit module 110 of the energy storage system is the DC bus. When the voltage on the DC bus fluctuates, the second input unit 310 will stabilize the input voltage of the DC bus. voltage, and output the stable DC bus voltage to the subsequent circuit. The fourth capacitor C4 of the second input unit 310 is used for voltage stabilization, and the voltage stabilization function is achieved by utilizing the charging and discharging characteristics of the energy storage element of the capacitor. The seventh diode D7 of the second input unit 310 is used to prevent reverse voltage. Since there is an energy storage element in the subsequent circuit, a diode is provided in the second input unit 310 to utilize the unidirectional conduction characteristics of the diode to avoid direct current The busbar causes impact.

The second controller power supply unit 320 is configured to reduce the voltage of the DC bus and output the reduced DC bus voltage to the second PWM controller. Since the input voltage of the second PWM controller 330 is relatively small, a voltage reduction circuit needs to be provided to reduce the input voltage when powering the second PWM controller 330 . For example, the voltage reduction control 321 of the second controller power supply unit 320 is actually equivalent to a combination of a signal generator and a switching tube structure. The buck controller 321 , the eighth diode D8 , the first inductor L1 and the fifth capacitor C5 form a BUCK circuit to process the DC bus voltage and transmit it to the second PWM controller 330 . It should be noted that this embodiment does not limit the circuit type and specific arrangement of the second controller power supply unit 320 .

FIG. 9 is a schematic circuit diagram of the primary circuit unit of the resonant circuit module provided by the embodiment of the present application. FIG. 10 is a circuit schematic diagram of the second secondary circuit unit of the resonant circuit module provided by the embodiment of the present application. Referring to FIG. 9 , the primary circuit unit 350 includes: a first switching tube Q1, a second switching tube Q2, a second inductor L2 and a sixth capacitor C6;

The first terminal of the first switching tube Q1 serves as the first terminal CJDL1 of the primary circuit unit 350, the second terminal of the first switching tube Q1 is electrically connected to the first terminal of the second switching tube Q2, and the second terminal of the second switching tube Q2 The terminal serves as the second terminal CJDL2 of the primary circuit unit 350; the control terminal of the first switching tube Q1 and the control terminal of the second switching tube Q2 serve as the control terminal KZ1 of the primary circuit unit 350;

The first end of the second inductor L2 is electrically connected to the second end of the first switch Q1, and the second end of the second inductor L2 serves as the third end CJDL3 of the primary circuit unit 350; the first end of the sixth capacitor C6 is connected to the second end of the first switch Q1. The second terminal of the two switch terminals Q2 is electrically connected, and the second terminal of the sixth capacitor C6 serves as the fourth terminal CJDL4 of the primary circuit unit 350;

Referring to FIG. 10 , the second secondary circuit unit 370 includes: a ninth diode D9 and a twelfth diode D10. The anode of the ninth diode D9 serves as the first terminal CJ21 of the second secondary circuit unit 370. The cathode of the nine-diode D9 is electrically connected to the third terminal CJ23 of the second secondary circuit unit 370; the anode of the twelfth diode D10 serves as the second terminal CJ22 of the second secondary circuit unit 370. The twelfth diode The cathode of D10 is electrically connected to the third terminal CJ23 of the second secondary circuit unit 370.

For example, the first switching tube Q1 and the second switching tube Q2 of the primary circuit unit 350 work in a soft switching state, the driver 340 controls the switching of the first switching tube Q1 and the second switching tube Q2 according to the control instruction, and the first switching tube Q1 The switching frequency of the second switching transistor Q2 is set at the resonant frequency point.

1 and 10 , the second secondary circuit unit 370 is configured to transmit the secondary output voltage of the resonant circuit module 110 to the flyback power module 120 . Since the voltage of the second secondary circuit 370 is induced by the third secondary coil 362 and the fourth secondary coil 363 of the second transformer 360, the induced voltage is AC. The ninth diode D9 and the twelfth diode D10 of the second secondary circuit unit 370 are used for rectification to convert the AC voltage induced by the third secondary coil 362 and the fourth secondary coil 363 into DC.

Figure 11 is a schematic circuit diagram of an auxiliary power supply for an energy storage system provided by an embodiment of the present application. Combined with Figure 1 and Figure 11, the working principle of the auxiliary power supply of the energy storage system is explained in detail below.

The power supply of the flyback power module 120 comes from the first input unit 210 . The first input unit 210 integrates the output voltage of the energy storage battery 130 and/or the secondary output voltage of the resonant circuit module 110 and outputs it to the first controller power supply unit 230 and the first transformer 250 . The first controller power supply unit 230 outputs the voltage of the first input unit 210 to the first PWM controller 220 . The first controller power supply unit 230 outputs the voltage of the first input unit 210 to the first PWM controller 220 . When the first PWM controller 220 operates, it sends a control signal to the switch unit 240, and the switch unit 240 turns on and off the first primary coil 251 of the first transformer 250 according to the control instructions of the first PWM controller 220. When the switch unit 240 is turned on, the first primary coil 251 of the first transformer 250 continuously stores energy; when the switch unit 240 is turned off, the inductive energy stored in the first primary coil 251 is released to other secondary coils of the first transformer 250 . The first secondary coil 252 of the first transformer 250 receives the energy conducted by the first primary coil 251 , and the first secondary coil 252 converts the energy into electrical energy and transmits it to the first PWM controller 220 through the first controller power supply unit 230 . The second secondary coil 253 of the first transformer 250 receives the energy of the first primary coil 251. The first secondary coil 252 converts the energy into electrical energy and transmits it to the first secondary circuit unit 260. The first secondary circuit unit 260 passes The power output terminal VOUT is output to the control unit of the energy storage system.

The power supply of the resonant circuit module 110 comes from the DC bus. The second input unit 310 stabilizes the voltage input by the DC bus and outputs it to the second controller power supply unit 320 and the primary circuit unit 350 . The second controller power supply unit 320 outputs the voltage of the second input unit 310 to the second PWM controller 330 . When the second PWM controller 330 is working, it sends a control signal to the driver 340, and the driver 340 controls the on and off of the primary circuit unit 350 according to the control instructions of the second PWM controller 330. When the primary circuit unit 350 is turned on, the second primary coil 361 of the second transformer 360 continuously stores energy; when the primary circuit unit 350 is turned off, the third secondary coil 362 and the fourth secondary coil 363 of the second transformer 360 receive energy. The energy conducted by the second primary coil 361 is converted into electrical energy by the third secondary coil 362 and the fourth secondary coil 363 and transmitted to the first input unit 210 of the flyback power module 130 through the second secondary circuit unit 370 .

It should be understood that various forms of the process shown above may be used, with steps reordered, added or deleted. For example, multiple steps described in this application can be executed in parallel, sequentially, or in different orders. As long as the desired results of the technical solution of this application can be achieved, there is no limitation here.

Claims

An auxiliary power supply for an energy storage system, including:

The resonant circuit module includes a first power supply input terminal, a second power supply input terminal, a first power supply output terminal and a second power supply output terminal; the first power supply input terminal and the second power supply input terminal are respectively connected to the DC bus. Positive voltage and negative voltage; the resonant circuit module works in open-loop mode, converting the DC bus voltage into a secondary output voltage. The positive voltage and negative voltage of the secondary output voltage pass through the first power supply output terminal and The second power supply output terminal outputs;

A flyback power supply module includes a third power supply input terminal, a fourth power supply input terminal, a fifth power supply input terminal, a sixth power supply input terminal and a power supply output terminal; the third power supply input terminal and the fourth power supply input terminal are respectively The positive voltage and negative voltage of the energy storage battery are connected, and the fifth power supply input terminal and the sixth power supply input terminal are respectively connected to the first power supply output terminal and the second power supply output of the resonant circuit module. end; the flyback power module operates in a closed-loop control mode, converting at least one of the voltage of the energy storage battery and the secondary output voltage of the resonant circuit module into an auxiliary power output voltage.
The power supply according to claim 1, wherein the resonant circuit module includes an asymmetric half-bridge structure or a symmetric half-bridge structure;

The flyback power module includes a single-tube flyback structure or a dual-tube flyback structure.
The power supply according to claim 1, wherein the flyback power supply module includes: a first input unit, a first pulse width modulation PWM controller, a first controller power supply unit, a switching unit, a first transformer, a first A secondary circuit unit and a feedback compensation unit; the first transformer includes a first primary coil, a first secondary coil and a second secondary coil;

The first terminal of the first input unit serves as the third power supply input terminal, the second terminal of the first input unit serves as the fourth power supply input terminal, and the third terminal of the first input unit serves as the third power supply input terminal. The fifth power supply input terminal, the fourth terminal of the first input unit serves as the sixth power supply input terminal; the fifth terminal of the first input unit is electrically connected to the first terminal of the first primary coil, The sixth terminal of the first input unit is grounded; the first input unit is configured to stabilize the input voltage;

The first end of the first controller power supply unit is electrically connected to the fifth end of the first input unit, and the second end of the first controller power supply unit is electrically connected to the first end of the first secondary coil. Electrically connected, the third end of the first controller power supply unit is electrically connected to the second end of the first secondary coil, the first end of the first secondary coil is grounded; the first controller power supply The fourth end of the unit is electrically connected to the first PWM controller, and the first controller power supply unit is configured to supply power to the first PWM controller;

The first end of the switch unit is electrically connected to the second end of the first primary coil, the second end of the switch unit is grounded, and the control end of the switch unit is electrically connected to the first PWM controller, The switch unit is configured to turn on or off the first primary coil branch in response to the control of the first PWM controller;

The first end of the first secondary circuit unit is electrically connected to the first end of the second secondary coil, and the second end of the first secondary circuit unit is electrically connected to the second end of the second secondary coil. terminals are electrically connected, the third terminal of the first secondary circuit unit serves as the power output terminal, and the fourth terminal of the secondary circuit is grounded; the first secondary circuit unit is configured to sense the first primary The electromagnetic changes in the coil generate the auxiliary power output voltage;

The first end of the feedback compensation unit is electrically connected to the power output end, the second end of the feedback compensation unit is electrically connected to the first PWM controller, and the first PWM controller is configured to operate according to the The feedback of the feedback compensation unit generates a control signal.
The power supply according to claim 3, wherein the first input unit includes: a first diode, a second diode, a third diode, a fourth diode and a first capacitor;

The anode of the first diode is connected to the positive voltage of the energy storage battery, and the cathode of the first diode serves as the fifth terminal of the first input unit;

The anode of the second diode is connected to the positive voltage of the secondary output voltage, and the cathode of the second diode is electrically connected to the cathode of the first diode;

The cathode of the third diode is connected to the negative voltage of the energy storage battery, and the anode of the third diode is connected to ground;

The cathode of the fourth diode is connected to the negative voltage of the secondary output voltage, and the anode of the fourth diode is connected to ground;

The first end of the first capacitor is electrically connected to the cathode of the first diode, and the second end of the first capacitor is grounded.
The power supply according to claim 3, wherein the first controller power supply unit includes: a first resistor, a second resistor, a third resistor, a second capacitor and a fifth diode;

The first resistor and the second resistor are connected in series between the first terminal and the fourth terminal of the first controller power supply unit; the fifth diode and the third resistor are connected in series between the first terminal and the fourth terminal of the first controller power supply unit. Between the third end and the fourth end of a controller power supply unit; the first end of the second capacitor is electrically connected to the fourth end of the first controller power supply unit, and the second end of the second capacitor Ground.
The power supply according to claim 3, wherein the first secondary circuit unit includes: a sixth diode and a third capacitor;

The anode of the sixth diode is electrically connected to the second terminal of the first secondary circuit unit, and the cathode of the sixth diode is electrically connected to the power output terminal; the third capacitor of the third capacitor is electrically connected to the output terminal of the power supply. One end is electrically connected to the power output end, and a second end of the third capacitor is electrically connected to the second end of the first secondary circuit unit.
The power supply according to claim 3, wherein the resonant circuit module includes: a second input unit, a second PWM controller, a second controller power supply unit, a driver, a primary circuit unit, a second transformer and a second secondary Circuit unit; the second transformer includes a second primary coil, a third secondary coil and a fourth secondary coil, and the second end of the third secondary coil is electrically connected to the first end of the fourth secondary coil. connect;

The first end of the second input unit serves as the first power supply input end, and the second end of the second input unit serves as the second power supply input end; the third end of the second input unit is connected to the first power supply input end. The first end of the primary circuit unit is electrically connected, and the fourth end of the second input unit is electrically connected to the second end of the primary circuit unit; the second input unit is configured to stabilize the input voltage;

The first end of the second controller power supply unit is electrically connected to the third end of the second input unit, and the second end of the second controller power supply unit is electrically connected to the fourth end of the second input unit. connection, the third end of the second controller power supply unit is electrically connected to the second PWM controller; the second controller power supply unit is configured to supply power to the second PWM controller;

The driver is connected between the second PWM controller and the control terminal of the primary circuit unit, and the driver is configured to control the primary circuit unit in response to control of the second PWM controller;

The third end of the primary circuit unit is electrically connected to the first end of the second primary coil, and the fourth end of the primary circuit unit is electrically connected to the second end of the second primary coil; the primary circuit The unit is configured to conduct or disconnect the second primary coil branch in response to control of the driver;

The first end of the second secondary circuit unit is electrically connected to the first end of the third secondary coil, and the second end of the second secondary circuit unit is electrically connected to the second end of the fourth secondary coil. terminals are electrically connected, the third terminal of the second secondary circuit unit serves as the first power supply output terminal, and the first terminal of the fourth secondary coil serves as the second power supply output terminal; the second The secondary circuit unit is configured to induce electromagnetic changes in the second primary coil to generate a secondary output voltage.
The power supply according to claim 7, wherein the second PWM controller and the first PWM controller are of the same model.
The power supply according to claim 7, wherein the second input unit includes: a seventh diode and a fourth capacitor; the anode of the seventh diode is connected to the positive voltage of the DC bus, and the The cathode of the seventh diode serves as the third terminal of the second input unit; the first terminal of the fourth capacitor is electrically connected to the cathode of the seventh diode, and the second terminal of the fourth capacitor Connect to the negative voltage of the DC bus and serve as the fourth terminal of the second input unit;

The second controller power supply unit includes: a buck controller, an eighth diode, a first inductor and a fifth capacitor; the first terminal of the buck controller and the third terminal of the second controller power supply unit One end is electrically connected, the second end of the buck controller is electrically connected to the second end of the second controller power supply unit, and the third end of the buck controller is electrically connected to the first end of the first inductor. terminal electrical connection;

The second end of the first inductor serves as the third end of the second controller power supply unit, the anode of the eighth diode is electrically connected to the second end of the buck controller, and the eighth The cathode of the diode is electrically connected to the third terminal of the buck controller, the first terminal of the fifth capacitor is electrically connected to the second terminal of the first inductor, and the second terminal of the fifth capacitor It is electrically connected to the third terminal of the buck controller.
The power supply according to claim 7, wherein the primary circuit unit includes: a first switch tube, a second switch tube, a second inductor and a sixth capacitor;

The first end of the first switch tube serves as the first end of the primary circuit unit, the second end of the first switch tube is electrically connected to the first end of the second switch tube, and the second switch The second end of the tube serves as the second end of the primary circuit unit; the control end of the first switching tube and the control end of the second switching tube serve as the control end of the primary circuit unit;

The first end of the second inductor is electrically connected to the second end of the first switch tube, and the second end of the second inductor serves as the third end of the primary circuit unit; the third end of the sixth capacitor One end is electrically connected to the second end of the second switch end, and the second end of the sixth capacitor serves as the fourth end of the primary circuit unit;

The second secondary circuit unit includes: a ninth diode and a twelfth diode, the anode of the ninth diode serves as the first end of the second secondary circuit unit, the ninth diode The cathode of the twelfth electrode tube is electrically connected to the third end of the second secondary circuit unit; the anode of the twelfth electrode tube serves as the second end of the second secondary circuit unit, and the twelfth electrode tube The cathode is electrically connected to the third terminal of the second secondary circuit unit.