Energy storage system discharge circuit

Abstract

The utility model belongs to energy transmission technical field discloses a kind of energy storage system discharge circuit, comprising: AC-DC soft start discharge circuit, AC soft start control circuit, DC soft start control circuit, bus discharge control circuit and control device;AC-DC soft start discharge circuit and control device are connected with AC soft start control circuit, DC soft start control circuit and bus discharge control circuit respectively;Control device is used to output control signal;AC-DC soft start discharge circuit includes AC access end, DC access end, bus access end and power resistance module;Power resistance module includes the first branch and the second branch with multiple power resistances respectively in series connection;AC soft start control circuit, DC soft start control circuit and bus discharge control circuit are used to respectively according to control signal control the conduction between AC access end, DC access end and bus access end.The utility model aims at reducing the circuit cost required by energy storage converter bus discharge and port discharge.

Description

Technical Field

[0001] This utility model relates to the field of energy transmission technology, and in particular to a discharge circuit for an energy storage system. Background Technology

[0002] Among related technologies, the development and popularization of renewable energy and related industries have further promoted the development of energy storage technology. Energy storage converters are bidirectional current-controllable conversion devices that connect energy storage battery systems to the power grid. Current energy storage industry-related requirements documents all specify that the port voltage of the energy storage converter must decrease to a safe voltage range within a specified time after a power outage.

[0003] However, energy storage converters typically have EMC certification requirements. During testing, adjusting EMC necessitates increasing the X / Y capacitance at the AC and / or DC ports. This leads to increased capacitance resistance and slower discharge rates at the AC and bus ports. To address this issue, current solutions generally involve configuring bus discharge circuits and port discharge circuits for the energy storage module. However, the discharge resistors in these circuits occupy excessive board space, resulting in high costs.

[0004] In summary, the technical problems existing in the relevant technologies need to be improved. Utility Model Content

[0005] This utility model aims to solve at least one of the technical problems existing in the prior art. To this end, this utility model proposes a discharge circuit for an energy storage system, the circuit comprising: an AC / DC soft-start discharge circuit, an AC soft-start control circuit, a DC soft-start control circuit, a bus discharge control circuit, and a control device;

[0006] The AC / DC soft-start discharge circuit is connected to the AC soft-start control circuit, the DC soft-start control circuit, and the bus discharge control circuit, respectively. The AC / DC soft-start discharge circuit includes an AC input terminal, a DC input terminal, a bus input terminal, and a power resistor module. The power resistor module includes a first branch and a second branch. The first branch is provided with a first resistor, a second resistor, and a third resistor connected in series. The second branch is provided with a fourth resistor, a fifth resistor, and a sixth resistor connected in series. The first branch is used to connect to the positive input, and the second branch is used to connect to the negative output.

[0007] The control device is connected to the AC soft start control circuit, the DC soft start control circuit and the bus discharge control circuit respectively, and is configured to output control signals to the AC soft start control circuit, the DC soft start control circuit and the bus discharge control circuit respectively.

[0008] The AC soft-start control circuit is used to control the conduction between the AC input terminal and the bus input terminal according to the control signal; the DC soft-start control circuit is used to control the conduction between the DC input terminal and the bus input terminal according to the control signal; and the bus discharge control circuit is used to control the conduction of the bus input terminal according to the control signal.

[0009] In some embodiments, the AC / DC soft-start discharge circuit includes a first disconnect switch, a second disconnect switch, a first diode, a second diode, and a rectifier bridge. The first pins of the first disconnect switch and the second disconnect switch are both connected to the power supply of the control circuit. The second pins of the first disconnect switch and the second disconnect switch are respectively connected to the AC soft-start control circuit. The first diode is connected in parallel between the first and second pins of the first disconnect switch, and the second diode is connected in parallel between the first and second pins of the second disconnect switch. The third pins of the first and second disconnect switches are respectively connected to the AC input terminal. The fourth pin of the first disconnect switch is connected to the second pin of the rectifier bridge, and the fourth pin of the second disconnect switch is connected to the third pin of the rectifier bridge. The first pin of the rectifier bridge is connected to the second branch, and the fourth pin of the rectifier bridge is connected to the first branch. The other end of the first branch and the other end of the second branch are connected to the bus input terminal.

[0010] In some embodiments, the AC soft-start control circuit includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a first PNP transistor, and a first NPN transistor. The AC control output terminal of the control device is connected to the seventh resistor and the emitter of the first PNP transistor, respectively. The other end of the seventh resistor is connected to the eighth resistor and the base of the first PNP transistor, respectively. The collector of the first PNP transistor is connected to the ninth resistor. The other end of the ninth resistor is connected to the tenth resistor and the base of the first NPN transistor, respectively. The other end of the tenth resistor is connected to the emitter of the first NPN transistor. The collector of the first NPN transistor is connected to the AC / DC soft-start discharge circuit. The other end of the eighth resistor and the emitter of the first NPN transistor are grounded, respectively.

[0011] In some embodiments, the first disconnecting switch and the second disconnecting switch are configured as high-voltage relays, the first and second pins of the high-voltage relays are the primary isolation side, and the third and fourth pins of the high-voltage relays are the secondary isolation side.

[0012] In some embodiments, the AC / DC soft-start discharge circuit includes a third disconnect switch, a fourth disconnect switch, a third diode, and a fourth diode. The first pins of the third disconnect switch and the fourth disconnect switch are both connected to the power supply of the control circuit. The second pins of the third disconnect switch and the fourth disconnect switch are respectively connected to the DC soft-start control circuit. The third diode is connected in parallel between the first and second pins of the third disconnect switch, and the fourth diode is connected in parallel between the first and second pins of the fourth disconnect switch. The DC input terminal includes a battery positive input terminal and a battery negative input terminal. The third pin of the third disconnect switch is connected to the battery positive input terminal, and the third pin of the fourth disconnect switch is connected to the battery negative input terminal. The fourth pin of the third disconnect switch is connected to the first branch, and the fourth pin of the fourth disconnect switch is connected to the second branch. The other end of the first branch and the other end of the second branch are connected to the bus input terminal.

[0013] In some embodiments, the DC soft-start control circuit includes an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, a first capacitor, a second NPN transistor, a second PNP transistor, and a first MOSFET. The DC control output terminal of the control device is connected to the eleventh resistor. The other end of the eleventh resistor is connected to the base of the first capacitor, the twelfth resistor, and the second NPN transistor, respectively. The other end of the twelfth resistor and the emitter of the second NPN transistor are both connected to the other end of the first capacitor. The collector of the second NPN transistor is connected to the thirteenth resistor and the fourteenth resistor, respectively. The other end of the thirteenth resistor is connected to the second power supply. The other end of the fourteenth resistor is connected to the base of the fifteenth resistor and the second PNP transistor, respectively. The other end of the fifteenth resistor and the emitter of the second PNP transistor are both connected to the power supply of the control circuit. The collector of the second PNP transistor is connected to the sixteenth resistor. The other end of the sixteenth resistor is connected to the gate of the first MOS transistor and the seventeenth resistor, respectively. The other end of the seventeenth resistor is connected to the source of the first MOS transistor. The drain of the first MOS transistor is connected to the AC / DC soft-start discharge circuit. The other end of the first capacitor and the source of the first MOS transistor are grounded.

[0014] In some embodiments, the third disconnect switch and the fourth disconnect switch are configured as high-voltage relays, with the first and second pins of the high-voltage relays serving as the primary isolation side and the third and fourth pins serving as the secondary isolation side.

[0015] In some embodiments, the AC / DC soft-start discharge circuit includes a fifth disconnect switch and a fifth diode. The first pin of the fifth disconnect switch is connected to the bus discharge control circuit, the second pin of the fifth disconnect switch is connected to the power supply of the control circuit, the fifth diode is connected in parallel between the first pin and the second pin of the fifth disconnect switch, the third pin of the fifth disconnect switch is connected to the first branch, the fourth pin of the fifth disconnect switch is connected to the second branch, and the other end of the first branch and the other end of the second branch are connected to the bus access terminal.

[0016] The bus discharge control circuit includes an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a twenty-fourth resistor, a second capacitor, a third NPN transistor, a third PNP transistor, and a second MOSFET. The DC control output terminal of the control device is connected to the eighteenth resistor. The other end of the eighteenth resistor is connected to the base of the second capacitor, the nineteenth resistor, and the third NPN transistor. The other end of the nineteenth resistor and the emitter of the third NPN transistor are both connected to the other end of the second capacitor. The collector of the third NPN transistor is connected to the twentyth and twenty-first resistors, respectively. The other end of resistor 20 is connected to the second power supply. The other end of resistor 21 is connected to resistor 22 and the base of the third PNP transistor. The other end of resistor 22 and the emitter of the third PNP transistor are both connected to the power supply of the control circuit. The collector of the third PNP transistor is connected to resistor 23. The other end of resistor 23 is connected to the gate of the second MOS transistor and resistor 24. The other end of resistor 24 is connected to the source of the second MOS transistor. The drain of the second MOS transistor is connected to the AC / DC soft-start discharge circuit. The other end of capacitor 2 and the source of the second MOS transistor are grounded.

[0017] In some embodiments, the fifth disconnecting switch is configured as a high-voltage relay, wherein the first and second pins of the high-voltage relay are the primary isolation side, and the third and fourth pins of the high-voltage relay are the secondary isolation side.

[0018] In some embodiments, the circuit further includes a first filter circuit and a second filter circuit;

[0019] The first filter circuit includes a third capacitor and a first electrolytic capacitor. The positive terminals of the third capacitor and the first electrolytic capacitor are both connected to the power supply of the control circuit in the DC soft start control circuit. The other end of the third capacitor and the negative terminal of the first electrolytic capacitor are grounded.

[0020] The second filter circuit includes a fourth capacitor and a second electrolytic capacitor. The positive terminals of both the fourth capacitor and the second electrolytic capacitor are connected to the power supply of the control circuit in the bus discharge control circuit, and the other end of the fourth capacitor and the negative terminal of the second electrolytic capacitor are grounded.

[0021] The beneficial effects of this utility model are as follows: A discharge circuit for an energy storage system is designed. During AC soft start, a control signal is sent to the AC soft start control circuit via a control device. The AC soft start control circuit controls the AC input terminal to conduct, and the resistor in the power resistor module is used as a pre-charging resistor to charge the bus capacitor, thus achieving AC soft start. During DC soft start, a control signal is sent to the DC soft start control circuit via a control device. The DC soft start control circuit controls the DC input terminal to conduct, and the resistor in the power resistor module is used as a pre-charging resistor to charge the bus capacitor, thus achieving DC soft start. During bus discharge, a control signal is sent to the bus discharge control circuit via a control device. The bus discharge control circuit controls the conduction between the bus input terminal and the AC / DC soft start discharge circuit, and the energy on the bus capacitor is discharged through the resistor in the power resistor module. Based on this, the same power resistor module is reused as both the soft start resistor and the discharge resistor, avoiding the need for separate bus discharge circuits and port discharge circuits, thus reducing the circuit cost required for bus discharge and port discharge of the energy storage converter. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0023] Figure 1 A schematic diagram of the structure of a discharge circuit for an energy storage system provided in an embodiment of this utility model;

[0024] Figure 2 A schematic diagram of an AC / DC soft-start discharge circuit provided for an embodiment of this utility model;

[0025] Figure 3 A schematic diagram of an AC soft-start control circuit provided for an embodiment of this utility model;

[0026] Figure 4 A schematic diagram of the DC soft-start control circuit and the first filter circuit provided for an embodiment of this utility model;

[0027] Figure 5 A schematic diagram of the bus discharge control circuit and the second filter circuit provided in the embodiment of this utility model.

[0028] In the diagram: Resistor R1, Resistor R2, Resistor R3, Resistor R4, Resistor R5, Resistor R6, Resistor R7, Resistor R8, Resistor R9, Resistor R10, Resistor R11, Resistor R12, Resistor R13, Resistor R14, Resistor R15, Resistor R16, Resistor R17, Resistor R18, Resistor R19, Resistor R20, Resistor R21, Resistor R22, Rectifier Bridge BD1, First Isolating Switch K1, Second Isolating Switch K1... Switch K2, third isolating switch K3, fourth isolating switch K4, fifth isolating switch K5, first diode D1, second diode D2, third diode D3, fourth diode D4, fifth diode D5, first capacitor C1, second capacitor C2, third capacitor C3, fourth capacitor C4, first electrolytic capacitor CE1, second electrolytic capacitor CE2, first PNP transistor Q1, first NPN transistor Q2, second NPN transistor Q3, second PNP transistor Q4, first MOSFET Q5, third NPN transistor Q6, third PNP transistor Q7, second MOSFET Q8. Detailed Implementation

[0029] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0030] Among related technologies, the development and popularization of renewable energy and related industries have further promoted the development of energy storage technology. Energy storage converters are bidirectional current-controllable conversion devices that connect energy storage battery systems to the power grid. Current energy storage industry-related requirements documents all specify that the port voltage of the energy storage converter must decrease to a safe voltage range within a specified time after a power outage.

[0031] However, energy storage converters typically have EMC certification requirements. During testing, adjusting EMC necessitates increasing the X / Y capacitance at the AC and / or DC ports. This leads to increased capacitance resistance and slower discharge rates at the AC and bus ports. To address this issue, current solutions generally involve configuring bus discharge circuits and port discharge circuits for the energy storage module. However, the discharge resistors in these circuits occupy excessive board space, resulting in high costs.

[0032] In view of this, this application provides a discharge circuit for an energy storage system. Figure 1 This is a schematic diagram of the structure of a discharge circuit for an energy storage system provided in an embodiment of this application. Figure 1The discharge circuit of the energy storage system may include, but is not limited to: AC / DC soft-start discharge circuit, AC soft-start control circuit, DC soft-start control circuit, bus discharge control circuit and control device.

[0033] The AC / DC soft start discharge circuit is connected to the AC soft start control circuit, the DC soft start control circuit, and the bus discharge control circuit, respectively. The AC / DC soft start discharge circuit includes an AC input terminal, a DC input terminal, a bus input terminal, and a power resistor module. The power resistor module includes a first branch and a second branch. The first branch is equipped with a first resistor R1, a second resistor R2, and a third resistor R3 connected in series. The second branch is equipped with a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6 connected in series. The first branch is used to connect to the positive input, and the second branch is used to connect to the negative output.

[0034] The control device is connected to the AC soft start control circuit, the DC soft start control circuit and the bus discharge control circuit respectively, and is configured to output control signals to the AC soft start control circuit, the DC soft start control circuit and the bus discharge control circuit respectively.

[0035] The AC soft start control circuit is used to control the conduction between the AC input terminal and the bus input terminal according to the control signal; the DC soft start control circuit is used to control the conduction between the DC input terminal and the bus input terminal according to the control signal; and the bus discharge control circuit is used to control the conduction of the bus input terminal according to the control signal.

[0036] Specifically, the AC / DC soft-start discharge circuit is the core multiplexing circuit in this embodiment. The first resistor R1, second resistor R2, third resistor R3, fourth resistor R4, fifth resistor R5, and sixth resistor R6 of the power resistor module are all power resistors. For example, 20W-400RJ power resistors can be selected for each. In AC and DC soft-start, these resistors act as pre-charging resistors to charge the bus capacitor. During bus discharge, the energy on the bus capacitor is then discharged through these resistors, achieving multiplexing.

[0037] On the other hand, the control device is connected to the AC soft start control circuit, the DC soft start control circuit, and the bus discharge control circuit, respectively. The AC and DC soft start discharge circuits are also connected to the three control circuits, forming a control link of control device-control circuit-soft start discharge circuit. During AC soft start, the control device controls the AC soft start control circuit through a control signal, making the AC input terminal and the bus input terminal conductive. AC current flows in from the AC input terminal and passes through the power resistor module to enter the bus input terminal. During DC soft start, the control device controls the DC soft start control circuit through a control signal, making the DC input terminal and the bus input terminal conductive. DC current flows in from the DC input terminal and passes through the power resistor module to enter the bus input terminal. During bus discharge, the control device controls the bus discharge control circuit through a control signal, making the positive and negative terminals of the bus input terminal conductive. The bus discharge current flows in from the positive terminal of the bus input terminal, passes through the power resistor module, and then flows out from the negative terminal of the bus input terminal.

[0038] When the energy storage converter starts up, the operator uses a control device to activate either the AC or DC soft starter. The soft starter waits until the bus voltage reaches the pre-charge voltage (e.g., a 30V difference between the bus voltage and the battery voltage) before disconnecting the soft starter circuit and activating the main power relay to complete the startup. Furthermore, the method described in this application can also be applied to scenarios such as on-board chargers and DC bus management for motor controllers.

[0039] This embodiment designs a discharge circuit for an energy storage system. During AC soft start, a control signal is sent to the AC soft start control circuit via a control device. The AC soft start control circuit controls the AC input terminal to conduct, and the resistor in the power resistor module serves as a pre-charging resistor for charging the bus capacitor, thus achieving AC soft start. During DC soft start, a control signal is sent to the DC soft start control circuit via a control device. The DC soft start control circuit controls the DC input terminal to conduct, and the resistor in the power resistor module serves as a pre-charging resistor for charging the bus capacitor, thus achieving DC soft start. During bus discharge, a control signal is sent to the bus discharge control circuit via a control device. The bus discharge control circuit controls the conduction between the bus input terminal and the AC / DC soft start discharge circuits, and the energy on the bus capacitor is discharged through the resistor in the power resistor module. Based on this, the same power resistor module is reused as both the soft start resistor and the discharge resistor, avoiding the need for separate bus discharge circuits and port discharge circuits, thus reducing the circuit cost required for bus discharge and port discharge of the energy storage converter.

[0040] refer to Figure 2In some embodiments, the AC / DC soft-start discharge circuit includes a first disconnect switch K1, a second disconnect switch K2, a first diode D1, a second diode D2, and a rectifier bridge BD1. The first pin of the first disconnect switch K1 and the first pin of the second disconnect switch K2 are both connected to the power supply of the control circuit. The second pin of the first disconnect switch K1 and the second pin of the second disconnect switch K2 are respectively connected to the AC soft-start control circuit. The first diode D1 is connected in parallel between the first pin and the second pin of the first disconnect switch K1, and the second diode D2 is connected in parallel between the first pin and the second pin of the second disconnect switch K2. The third pin of the first disconnect switch K1 and the third pin of the second disconnect switch K2 are respectively connected to the AC input terminal. The fourth pin of the first disconnect switch K1 is connected to the second pin of the rectifier bridge BD1, and the fourth pin of the second disconnect switch K2 is connected to the third pin of the rectifier bridge BD1. The first pin of the rectifier bridge BD1 is connected to the second branch, and the fourth pin of the rectifier bridge BD1 is connected to the first branch. The other end of the first branch and the other end of the second branch are connected to the bus input terminal.

[0041] It should be noted that, in order to illustrate the reuse effect, Figure 2 The AC / DC soft start discharge circuit also includes other parts for DC soft start and bus discharge, which can be described with reference to other embodiments.

[0042] Specifically, the conduction control operation is achieved through the first isolating switch K1 and the second isolating switch K2. In some embodiments, the first isolating switch K1 and the second isolating switch K2 are configured as high-voltage relays, with the first and second pins of the high-voltage relays forming the primary isolation side and the third and fourth pins forming the secondary isolation side, thus achieving high-voltage isolation control. In other embodiments, IGBT modules or power MOSFETs can also be used as the first isolating switch K1 and the second isolating switch K2.

[0043] The control circuit power supply is used to provide power to the control circuit on the isolated primary side, and can be set to a 5V power supply.

[0044] The communication access terminals include the GRIDA port of phase A on the schematic network side and the GRIDB port of phase B on the schematic network side.

[0045] The rectifier bridge BD1 is used to convert the input AC power into DC power, which is then supplied to the subsequent power resistor module and bus input terminal.

[0046] The AC / DC soft starter circuit described above enables the AC / DC soft starter circuit to support AC soft start.

[0047] refer to Figure 3In some embodiments, the AC soft-start control circuit includes a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, a first PNP transistor Q1, and a first NPN transistor Q2. The AC control output terminal of the control device is connected to the seventh resistor R7 and the emitter of the first PNP transistor Q1, respectively. The other end of the seventh resistor R7 is connected to the eighth resistor R8 and the base of the first PNP transistor Q1, respectively. The collector of the first PNP transistor Q1 is connected to the ninth resistor R9. The other end of the ninth resistor R9 is connected to the tenth resistor R10 and the base of the first NPN transistor Q2, respectively. The other end of the tenth resistor R10 is connected to the emitter of the first NPN transistor Q2. The collector of the first NPN transistor Q2 is connected to the AC / DC soft-start discharge circuit. The other end of the eighth resistor R8 and the emitter of the first NPN transistor Q2 are grounded, respectively.

[0048] In addition, Figure 3 AC_RLY_SOFT_CONA indicates the port where the AC soft start control circuit is connected to the control device, and SOFT_RLA indicates the port where the AC soft start control circuit is connected to the AC / DC soft start discharge circuit.

[0049] Specifically, the control device sends different control signals to the three control circuits. The signal used to control the AC soft start control circuit is defined as the AC control signal. The first isolating switch K1 and the second isolating switch K2 actually share the same AC control signal for control.

[0050] The control is active high. When the AC control signal is high, for example, 5V, the voltage across the first PNP transistor Q1 is divided by the seventh resistor R7 and the eighth resistor R8. be The voltage is reduced to -2.5V. Since its normal turn-on voltage is -1.2V, this ensures that the first PNP transistor Q1 is turned on. Then, through the voltage divider of the ninth resistor R9 and the tenth resistor R10, the voltage of the first NPN transistor Q2 is reduced to -2.5V. be The voltage is 4.48V. Since its normal conduction voltage is 1.2V, it can also ensure that the first NPN transistor Q2 is turned on, so that SOFT_RLA is connected to ground, thereby closing the first disconnect switch K1 and the second disconnect switch K2, and connecting the AC input terminal and the bus input terminal to realize the control of AC soft start.

[0051] refer to Figure 2In some embodiments, the AC / DC soft-start discharge circuit includes a third disconnect switch K3, a fourth disconnect switch K4, a third diode D3, and a fourth diode D4. The first pins of the third disconnect switch K3 and the fourth disconnect switch K4 are both connected to the power supply of the control circuit. The second pins of the third disconnect switch K3 and the fourth disconnect switch K4 are respectively connected to the DC soft-start control circuit. The third diode D3 is connected in parallel between the first and second pins of the third disconnect switch K3, and the fourth diode D4 is connected in parallel between the first and second pins of the fourth disconnect switch K4. The DC input terminal includes a battery positive input terminal and a battery negative input terminal. The third pin of the third disconnect switch K3 is connected to the battery positive input terminal, and the third pin of the fourth disconnect switch K4 is connected to the battery negative input terminal. The fourth pin of the third disconnect switch K3 is connected to the first branch, and the fourth pin of the fourth disconnect switch K4 is connected to the second branch. The other end of the first branch and the other end of the second branch are connected to the bus input terminal.

[0052] It should be noted that, in order to illustrate the reuse effect, Figure 2 The AC / DC soft-start discharge circuit also includes other parts for AC soft-start and bus discharge, which can be described with reference to other embodiments.

[0053] Specifically, the conduction control is achieved through the third disconnect switch K3 and the fourth disconnect switch K4. In some embodiments, the third disconnect switch K3 and the fourth disconnect switch K4 are configured as high-voltage relays, with the first and second pins of the high-voltage relay serving as the primary isolation side and the third and fourth pins serving as the secondary isolation side, thus achieving high-voltage isolation control. In other embodiments, IGBT modules or power MOSFETs can also be used as the third disconnect switch K3 and the fourth disconnect switch K4.

[0054] The control circuit power supply is used to provide power to the control circuit on the isolated primary side, and can be set to a 5V power supply.

[0055] The DC input terminals include the BAT+ port, which indicates the positive terminal of the battery, and the BAT- port, which indicates the negative terminal of the battery.

[0056] The AC / DC soft start discharge circuit described above enables the AC / DC soft start discharge circuit to support DC soft start.

[0057] refer to Figure 4In some embodiments, the DC soft-start control circuit includes an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, a first capacitor C1, a second NPN transistor Q3, a second PNP transistor Q4, and a first MOSFET Q5. The DC control output terminal of the control device is connected to the eleventh resistor R11. The other end of the eleventh resistor R11 is connected to the base of the first capacitor C1, the twelfth resistor R12, and the second NPN transistor Q3, respectively. The other end of the twelfth resistor R12 and the emitter of the second NPN transistor Q3 are both connected to the other end of the first capacitor C1. The collector of the second NPN transistor Q3 is connected to the thirteenth resistor R17. Resistor R13 and the fourteenth resistor R14 are connected. The other end of the thirteenth resistor R13 is connected to the second power supply. The other end of the fourteenth resistor R14 is connected to the fifteenth resistor R15 and the base of the second PNP transistor Q4. The other end of the fifteenth resistor R15 and the emitter of the second PNP transistor Q4 are both connected to the power supply of the control circuit. The collector of the second PNP transistor Q4 is connected to the sixteenth resistor R16. The other end of the sixteenth resistor R16 is connected to the gate of the first MOSFET Q5 and the seventeenth resistor R17. The other end of the seventeenth resistor R17 is connected to the source of the first MOSFET Q5. The drain of the first MOSFET Q5 is connected to the AC / DC soft-start discharge circuit. The other end of the first capacitor C1 and the source of the first MOSFET Q5 are grounded.

[0058] For ease of observation, Figure 4 The DC soft start control circuit is divided into two parts connected via the BUS+_RLY_SOFT port. Furthermore, BUS+_RLY_SOFT_CON indicates the port connecting the DC soft start control circuit to the control device, and DC_SOFT_RLY indicates the port connecting the DC soft start control circuit to the AC / DC soft start discharge circuit.

[0059] Specifically, the control signal sent by the control device to control the DC soft start control circuit is defined as a DC control signal. The third disconnect switch K3 and the fourth disconnect switch K4 actually share the same DC control signal for control.

[0060] The first MOSFET, Q5, is an N-channel enhancement-mode MOSFET.

[0061] For example, the second power supply is set to 15V, the control circuit power supply is set to 5V, and the control is active high. When the DC control signal is high, for example, 5V, the eleventh resistor R11 and the twelfth resistor R12 divide the voltage of the second NPN transistor Q3. beThe voltage reaches 4.16V. Since its normal on-state voltage is 1.2V, it ensures that the second NPN transistor Q3 is turned on, connecting BUS+_RLY_SOFT to ground. This allows the power supply of the control circuit, which serves as the pull-up signal, to be divided by resistors fourteen (R14) and fifteen (R15), thus reducing the voltage of the second PNP transistor Q4 to 4.16V. be The voltage is -2.5V. Since its normal conduction voltage is -1.2V, it can ensure that the second PNP transistor Q4 is turned on. When the second PNP transistor Q4 is turned on, the pull-up signal is divided by the sixteenth resistor R16 and the seventeenth resistor R17, so that the gate-source voltage of the first MOSFET Q5 is 4.69V. Since its normal conduction voltage is 2.5V, it ensures that the first MOSFET Q5 is turned on, so that DC_SOFT_RLY is connected to ground, thereby closing the third isolating switch K3 and the fourth isolating switch K4, and connecting the DC input terminal with the bus input terminal, realizing the control of DC soft start.

[0062] refer to Figure 2 In some embodiments, the AC / DC soft-start discharge circuit includes a fifth disconnect switch K5 and a fifth diode D5. The first pin of the fifth disconnect switch K5 is connected to the bus discharge control circuit, the second pin of the fifth disconnect switch K5 is connected to the power supply of the control circuit, the fifth diode D5 is connected in parallel between the first pin and the second pin of the fifth disconnect switch K5, the third pin of the fifth disconnect switch K5 is connected to the first branch, the fourth pin of the fifth disconnect switch K5 is connected to the second branch, and the other end of the first branch and the other end of the second branch are connected to the bus access terminal.

[0063] It should be noted that, in order to illustrate the reuse effect, Figure 2 The AC / DC soft-start discharge circuit also includes other parts for AC soft-start and DC soft-start, which can be described with reference to other embodiments.

[0064] Specifically, the conduction control is achieved through the fifth isolating switch K5. In some embodiments, the fifth isolating switch K5 is configured as a high-voltage relay, with the first and second pins of the high-voltage relay forming the primary isolation side, and the third and fourth pins forming the secondary isolation side. High-voltage isolation control is achieved through the high-voltage relay. In other embodiments, an IGBT module or a power MOSFET can also be used as the fifth isolating switch K5.

[0065] The control circuit power supply is used to provide power to the control circuit on the isolated primary side, and can be set to a 5V power supply.

[0066] The busbar connection includes a BUS+ port indicating the positive terminal and a BUS- port indicating the negative terminal.

[0067] The AC / DC soft-start discharge circuit described above enables the AC / DC soft-start discharge circuit to support bus discharge.

[0068] refer to Figure 5 The bus discharge control circuit includes resistors R18 (18th), R19 (19th), R20 (20th), R21 (21st), R22 (22nd), R23rd, and R24th, capacitor C2 (2nd), NPN transistor Q6 (3rd), PNP transistor Q7 (3rd), and MOSFET Q8 (2nd). The DC control output terminal of the control device is connected to resistor R18. The other end of resistor R18 is connected to capacitor C2, resistor R19, and the base of NPN transistor Q6. The other end of resistor R19 and the emitter of NPN transistor Q6 are both connected to the other end of capacitor C2. The collector of NPN transistor Q6 is connected to resistor R20 (20th). The 21st resistor R21 is connected to the 20th resistor R20. The other end of the 21st resistor R21 is connected to the 22nd resistor R22 and the base of the third PNP transistor Q7. The other end of the 22nd resistor R22 and the emitter of the third PNP transistor Q7 are both connected to the control circuit power supply. The collector of the third PNP transistor Q7 is connected to the 23rd resistor. The other end of the 23rd resistor is connected to the gate of the second MOSFET Q8 and the 24th resistor. The other end of the 24th resistor is connected to the source of the second MOSFET Q8. The drain of the second MOSFET Q8 is connected to the AC / DC soft-start discharge circuit. The other end of the second capacitor C2 and the source of the second MOSFET Q8 are grounded.

[0069] For ease of observation, Figure 5 The bus discharge control circuit is divided into two parts connected via the DIS_RLY_SOFT port. Furthermore, DIS_RLY1_SOFT_CON indicates the port connecting the bus discharge control circuit to the control device, and DIS_RLY indicates the port connecting the bus discharge control circuit to the AC / DC soft-start discharge circuit.

[0070] The second MOSFET, Q8, is an N-channel enhancement-mode MOSFET.

[0071] Specifically, the control signal sent by the control device to control the bus discharge control circuit is defined as the discharge control signal.

[0072] For example, the second power supply is set to 15V, the control circuit power supply is set to 5V, and the control is active high. When the discharge control signal is high, for example, 5V, the eighteenth resistor R18 and the nineteenth resistor R19 divide the voltage of the third NPN transistor Q6. beThe voltage reaches 4.16V. Since its normal on-state voltage is 1.2V, it ensures that the third NPN transistor Q6 is turned on, connecting DIS_RLY_SOFT to ground. This allows the power supply of the control circuit, which serves as a pull-up signal, to be divided by the twenty-first resistor R21 and the twenty-second resistor R22, thus reducing the voltage of the third PNP transistor Q7. be The voltage is -2.5V. Since its normal conduction voltage is -1.2V, it can ensure that the third PNP transistor Q7 is turned on. When the third PNP transistor Q7 is turned on, the pull-up signal is divided by the twenty-third and twenty-fourth resistors, making the gate-source voltage of the second MOSFET Q8 4.69V. Since its normal conduction voltage is 2.5V, it ensures that the second MOSFET Q8 is turned on, so that DIS_RLY is connected to ground, thereby closing the fifth isolating switch K5, and connecting the first and second branches between the bus access terminals to achieve bus discharge control.

[0073] In some embodiments, the circuit further includes a first filter circuit and a second filter circuit;

[0074] The first filter circuit includes a third capacitor C3 and a first electrolytic capacitor CE1. The positive terminals of the third capacitor C3 and the first electrolytic capacitor CE1 are both connected to the power supply of the control circuit in the DC soft start control circuit, and the other end of the third capacitor C3 and the negative terminal of the first electrolytic capacitor CE1 are grounded.

[0075] The second filter circuit includes a fourth capacitor C4 and a second electrolytic capacitor CE2. The positive terminals of both the fourth capacitor C4 and the second electrolytic capacitor CE2 are connected to the power supply of the control circuit in the bus discharge control circuit, and the other end of the fourth capacitor C4 and the negative terminal of the second electrolytic capacitor CE2 are grounded.

[0076] Furthermore, to improve the accuracy of circuit control, corresponding first filter circuits can be set for the control circuit power supply connected to the DC soft start control circuit and the control circuit power supply connected to the bus discharge control circuit (see reference). Figure 4 ) and second filter circuit (reference) Figure 5 This filters out high and low frequency interference in the power supply, improving the accuracy of circuit control.

[0077] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0078] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0079] In the description of this utility model, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0080] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A discharge circuit for an energy storage system, characterized in that, The circuit includes: an AC / DC soft start discharge circuit, an AC soft start control circuit, a DC soft start control circuit, a bus discharge control circuit, and a control device. The AC / DC soft-start discharge circuit is connected to the AC soft-start control circuit, the DC soft-start control circuit, and the bus discharge control circuit, respectively. The AC / DC soft-start discharge circuit includes an AC input terminal, a DC input terminal, a bus input terminal, and a power resistor module. The power resistor module includes a first branch and a second branch. The first branch is provided with a first resistor, a second resistor, and a third resistor connected in series. The second branch is provided with a fourth resistor, a fifth resistor, and a sixth resistor connected in series. The first branch is used to connect to the positive input, and the second branch is used to connect to the negative output. The control device is connected to the AC soft start control circuit, the DC soft start control circuit and the bus discharge control circuit respectively, and is configured to output control signals to the AC soft start control circuit, the DC soft start control circuit and the bus discharge control circuit respectively. The AC soft-start control circuit is used to control the conduction between the AC input terminal and the bus input terminal according to the control signal; the DC soft-start control circuit is used to control the conduction between the DC input terminal and the bus input terminal according to the control signal; and the bus discharge control circuit is used to control the conduction of the bus input terminal according to the control signal.

2. The circuit according to claim 1, characterized in that, The AC / DC soft-start discharge circuit includes a first disconnect switch, a second disconnect switch, a first diode, a second diode, and a rectifier bridge. The first pins of both the first and second disconnect switches are connected to the power supply of the control circuit. The second pins of both the first and second disconnect switches are connected to the AC soft-start control circuit. The first diode is connected in parallel between the first and second pins of the first and second disconnect switches, and the second diode is connected in parallel between the first and second pins of the second disconnect switch. The third pins of both the first and second disconnect switches are connected to the AC input terminal. The fourth pin of the first disconnect switch is connected to the second pin of the rectifier bridge, and the fourth pin of the second disconnect switch is connected to the third pin of the rectifier bridge. The first pin of the rectifier bridge is connected to the second branch, and the fourth pin of the rectifier bridge is connected to the first branch. The other ends of the first and second branches are connected to the bus input terminal.

3. The circuit according to claim 2, characterized in that, The AC soft-start control circuit includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a first PNP transistor, and a first NPN transistor. The AC control output terminal of the control device is connected to the seventh resistor and the emitter of the first PNP transistor, respectively. The other end of the seventh resistor is connected to the eighth resistor and the base of the first PNP transistor, respectively. The collector of the first PNP transistor is connected to the ninth resistor. The other end of the ninth resistor is connected to the tenth resistor and the base of the first NPN transistor, respectively. The other end of the tenth resistor is connected to the emitter of the first NPN transistor. The collector of the first NPN transistor is connected to the AC / DC soft-start discharge circuit. The other end of the eighth resistor and the emitter of the first NPN transistor are grounded, respectively.

4. The circuit according to claim 2, characterized in that, The first disconnect switch and the second disconnect switch are configured as high-voltage relays, with the first and second pins of the high-voltage relays serving as the primary isolation side and the third and fourth pins serving as the secondary isolation side.

5. The circuit according to claim 1, characterized in that, The AC / DC soft-start discharge circuit includes a third disconnect switch, a fourth disconnect switch, a third diode, and a fourth diode. The first pins of the third and fourth disconnect switches are both connected to the power supply of the control circuit. The second pins of the third and fourth disconnect switches are respectively connected to the DC soft-start control circuit. The third diode is connected in parallel between the first and second pins of the third and fourth disconnect switches, and the fourth diode is connected in parallel between the first and second pins of the fourth disconnect switch. The DC input terminal includes a battery positive input terminal and a battery negative input terminal. The third pin of the third disconnect switch is connected to the battery positive input terminal, and the third pin of the fourth disconnect switch is connected to the battery negative input terminal. The fourth pin of the third disconnect switch is connected to the first branch, and the fourth pin of the fourth disconnect switch is connected to the second branch. The other ends of the first and second branches are connected to the bus input terminal.

6. The circuit according to claim 5, characterized in that, The DC soft-start control circuit includes an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, a first capacitor, a second NPN transistor, a second PNP transistor, and a first MOSFET. The DC control output terminal of the control device is connected to the eleventh resistor. The other end of the eleventh resistor is connected to the base of the first capacitor, the twelfth resistor, and the second NPN transistor. The other end of the twelfth resistor and the emitter of the second NPN transistor are both connected to the other end of the first capacitor. The collector of the second NPN transistor is connected to the thirteenth resistor and the fourteenth resistor. The other end of the thirteenth resistor is connected to the second power supply. The other end of the fourteenth resistor is connected to the fifteenth resistor and the base of the second PNP transistor. The other end of the fifteenth resistor and the emitter of the second PNP transistor are both connected to the power supply of the control circuit. The collector of the second PNP transistor is connected to the sixteenth resistor. The other end of the sixteenth resistor is connected to the gate of the first MOS transistor and the seventeenth resistor. The other end of the seventeenth resistor is connected to the source of the first MOS transistor. The drain of the first MOS transistor is connected to the AC / DC soft-start discharge circuit. The other end of the first capacitor and the source of the first MOS transistor are grounded.

7. The circuit according to claim 5, characterized in that, The third and fourth disconnect switches are configured as high-voltage relays, with the first and second pins of the high-voltage relays serving as the primary isolation side and the third and fourth pins serving as the secondary isolation side.

8. The circuit according to claim 1, characterized in that, The AC / DC soft-start discharge circuit includes a fifth disconnect switch and a fifth diode. The first pin of the fifth disconnect switch is connected to the bus discharge control circuit, the second pin of the fifth disconnect switch is connected to the power supply of the control circuit, the fifth diode is connected in parallel between the first and second pins of the fifth disconnect switch, the third pin of the fifth disconnect switch is connected to the first branch, the fourth pin of the fifth disconnect switch is connected to the second branch, and the other end of the first branch and the other end of the second branch are connected to the bus access terminal. The bus discharge control circuit includes an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a twenty-fourth resistor, a second capacitor, a third NPN transistor, a third PNP transistor, and a second MOSFET. The DC control output terminal of the control device is connected to the eighteenth resistor. The other end of the eighteenth resistor is connected to the base of the second capacitor, the nineteenth resistor, and the third NPN transistor. The other end of the nineteenth resistor and the emitter of the third NPN transistor are both connected to the other end of the second capacitor. The collector of the third NPN transistor is connected to the twentyth and twenty-first resistors, respectively. The other end of resistor 20 is connected to the second power supply. The other end of resistor 21 is connected to resistor 22 and the base of the third PNP transistor. The other end of resistor 22 and the emitter of the third PNP transistor are both connected to the power supply of the control circuit. The collector of the third PNP transistor is connected to resistor 23. The other end of resistor 23 is connected to the gate of the second MOS transistor and resistor 24. The other end of resistor 24 is connected to the source of the second MOS transistor. The drain of the second MOS transistor is connected to the AC / DC soft-start discharge circuit. The other end of capacitor 2 and the source of the second MOS transistor are grounded.

9. The circuit according to claim 8, characterized in that, The fifth disconnecting switch is configured as a high-voltage relay, with the first and second pins of the high-voltage relay serving as the primary isolation side, and the third and fourth pins of the high-voltage relay serving as the secondary isolation side.

10. The circuit according to claim 1, characterized in that, The circuit also includes a first filter circuit and a second filter circuit. The first filter circuit includes a third capacitor and a first electrolytic capacitor. The positive terminals of the third capacitor and the first electrolytic capacitor are both connected to the power supply of the control circuit in the DC soft start control circuit. The other end of the third capacitor and the negative terminal of the first electrolytic capacitor are grounded. The second filter circuit includes a fourth capacitor and a second electrolytic capacitor. The positive terminals of both the fourth capacitor and the second electrolytic capacitor are connected to the power supply of the control circuit in the bus discharge control circuit, and the other end of the fourth capacitor and the negative terminal of the second electrolytic capacitor are grounded.

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