Power supply system, protection method and protection circuit

Abstract

The invention discloses a power supply system, a protection method and a protection circuit. The system comprises a controller and the protection circuit. The protection circuit is connected in series between a direct current source and a post-stage circuit of the power supply system; the protection circuit comprises a semiconductor switch module and an explosion fuse. The semiconductor switch module and the explosion fuse are connected in parallel; and the controller is used for sending out a first signal, controlling the semiconductor switch module to be switched on and controlling the explosion fuse to be switched off. Under the abnormal working condition, the controller can be conducted in a pilot mode, the semiconductor switch module bypasses the explosion fuse, energy shunting is achieved, voltage at the two ends of the explosion fuse is reduced, and meanwhile current passing through the explosion fuse is reduced, so that rapid disconnection of the explosion fuse is facilitated, and due to the fact that the voltage at the two ends of the explosion fuse is small, the explosion fuse cannot be damaged. And the passing current can be neglected, so that the arc discharge phenomenon is avoided, the power supply system is protected, and the safety requirement is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power electronics, in particular to a power supply system, a protection method and a protection circuit. BACKGROUND

[0002] With the development of new energy, the voltage level or current level is getting higher and higher, such as photovoltaic systems or energy storage systems, etc. Therefore, when overvoltage or overcurrent occurs in the new energy system, the protection circuit needs to disconnect the direct current power supply from the subsequent stage in time. The existing protection circuit mainly includes mechanical or fuse types. The protection circuit of mechanical or fuse type applied in the new energy system generally has slow response speed and poor timeliness, which cannot meet the requirements of safety regulations. SUMMARY

[0003] Therefore, the present application provides a power supply system, a protection method and a protection circuit, which can quickly cut off the circuit when overcurrent or overvoltage occurs in the power supply system, thereby playing a protection role.

[0004] The present application provides a power supply system, comprising: a controller and a protection circuit; the protection circuit is connected in series between a direct current source of the power supply system and a subsequent circuit; the protection circuit comprises: a semiconductor switch module and an explosion fuse; the semiconductor switch module and the explosion fuse are connected in parallel; the controller is used to send a first signal to control the semiconductor switch module to be turned on and control the explosion fuse to be disconnected.

[0005] In a possible implementation, the controller sends a second signal to control the semiconductor switch module to be disconnected and the explosion fuse to be turned on.

[0006] In a possible implementation, the first signal is sent when the voltage or current of the protection circuit exceeds the corresponding preset range or a fault instruction sent by an upper computer is received.

[0007] The second signal is that the voltage or current of the protection circuit is within the corresponding preset range and no fault instruction sent by the upper computer is received.

[0008] In a possible implementation, the controller is further used to control the semiconductor switch module to be disconnected after the explosion fuse is disconnected.

[0009] In a possible implementation, the semiconductor switch module comprises: a first controllable switching device.

[0010] The first controllable switching device is connected in parallel with the explosion fuse.

[0011] In a possible implementation, the semiconductor switch module comprises: a first controllable switching device and a second controllable switching device; the first controllable switching device and the second controllable switching device are connected in series and are connected in parallel with the explosion fuse; the controller is configured to send a first signal to control the semiconductor switch module to be turned on, and specifically comprises: when the current direction is from the direct current source to the subsequent circuit, the first controllable switching device is controlled to be turned off; and when the current direction is from the subsequent circuit to the direct current source, the second controllable switching device is controlled to be turned off; the controller is configured to send a second signal to control the semiconductor switch module to be turned off, and specifically comprises: one of the first controllable switching device and the second controllable switching device is controlled to be turned on according to the current direction.

[0012] In a possible implementation, the semiconductor switch module comprises: a first controllable switching device, a first diode, a second diode, a third diode, and a fourth diode; the anode and the cathode of the first diode are connected to the first end of the explosion fuse and the cathode of the third diode respectively, and the anode of the third diode is connected to the second end of the explosion fuse; the cathode and the anode of the fourth diode are connected to the first end of the explosion fuse and the anode of the second diode respectively, and the cathode of the second diode is connected to the second end of the explosion fuse; and the first end and the second end of the first controllable switching tube are connected to the cathode of the first diode and the anode of the fourth diode respectively.

[0013] In a possible implementation, the direct current source is an energy storage battery or a photovoltaic array; when the direct current source is an energy storage battery, the power supply system further comprises an energy storage converter, and the protection circuit is connected between the energy storage battery and the energy storage converter; when the direct current source is a photovoltaic array, the power supply system further comprises an inverter, and the protection circuit is connected between the photovoltaic array and the inverter.

[0014] In a possible implementation, the power supply system comprises two protection circuits: a first protection circuit and a second protection circuit; the first protection circuit is connected between the positive electrode of the direct current source and the subsequent circuit, and the second protection circuit is connected between the negative electrode of the direct current source and the subsequent circuit.

[0015] In a possible implementation, the controller is further configured to directly control the explosion fuse to be turned off when the voltage or the current of the protection circuit exceeds a preset threshold value, and the preset threshold value is greater than the maximum value of the preset range.

[0016] In a possible implementation, the power supply system further comprises: an absorption circuit and a clamping circuit connected in parallel across the semiconductor switch module; the absorption circuit comprises a resistor and a capacitor connected in series; and the clamping circuit comprises a varistor or a Schottky diode.

[0017] This application also provides a protection method for a power supply system, the power supply system including a protection circuit connected in series between the DC source and the subsequent circuit of the power supply system; the protection circuit includes: a semiconductor switch module and an explosive fuse; the semiconductor switch module and the explosive fuse are connected in parallel; a first signal is issued to control the semiconductor switch module to conduct and to control the explosive fuse to disconnect.

[0018] One possible implementation further includes: issuing a second signal to control the semiconductor switch module to disconnect and control the explosive fuse to conduct; the first signal is when the voltage or current of the protection circuit exceeds a corresponding preset range, or when a fault command is received from the host computer; the second signal is when the voltage or current of the protection circuit is within the corresponding preset range, and no fault command is received from the host computer.

[0019] One possible implementation also includes: controlling the semiconductor switch module to disconnect after the explosive fuse is disconnected.

[0020] One possible implementation further includes: directly controlling the exploding fuse to disconnect when the voltage or current of the protection circuit exceeds a preset threshold, wherein the preset threshold is greater than the maximum value of the preset range.

[0021] This application also provides a protection circuit, including: a semiconductor switch module and an explosive fuse; the semiconductor switch module and the explosive fuse are connected in parallel.

[0022] In one possible implementation, the semiconductor switch module includes: a first controllable switch device; the first controllable switch device is connected in parallel with the explosive fuse.

[0023] In one possible implementation, the semiconductor switch module includes: a first controllable switch device and a second controllable switch device; the first controllable switch device and the second controllable switch device are connected in series and then connected in parallel with the explosive fuse.

[0024] In one possible implementation, the semiconductor switch module includes: a first controllable switch device, a first diode, a second diode, a third diode, and a fourth diode; the anode and cathode of the first diode are respectively connected to a first end of the explosive fuse and the cathode of the third diode, and the anode of the third diode is connected to a second end of the explosive fuse; the cathode and anode of the fourth diode are respectively connected to a first end of the explosive fuse and the anode of the second diode, and the cathode of the second diode is connected to a second end of the explosive fuse; the first end and the second end of the first controllable switch device are respectively connected to the cathode of the first diode and the anode of the fourth diode.

[0025] The power system provided in this application embodiment includes a protection circuit comprising a semiconductor switching module and a detonating fuse connected in parallel. This is designed so that the two work together to quickly and promptly cut off the power supply path when it is necessary to disconnect the power supply, thus protecting the power system. Because the voltage or current level of the power system is relatively high, if the detonating fuse were to open directly, it could cause arcing and prolong the fuse's opening time. Therefore, in abnormal operating conditions, the controller can first turn on the semiconductor switching module, which will bypass the detonating fuse, thereby diverting energy, reducing the voltage across the detonating fuse, and simultaneously reducing the current flowing through it. This facilitates the rapid opening of the detonating fuse. Furthermore, because the voltage across the detonating fuse is relatively low, the current flowing through it is negligible, thus preventing arcing and protecting the power system to meet safety regulations. Attached Figure Description

[0026] Figure 1 A schematic diagram of a power supply system provided in an embodiment of this application;

[0027] Figure 2 This is a schematic diagram of an explosive fuse;

[0028] Figure 3 A schematic diagram of a protection circuit provided in an embodiment of this application;

[0029] Figure 4 A schematic diagram of a protection circuit provided in an embodiment of this application;

[0030] Figure 5 A schematic diagram of a protection circuit provided in an embodiment of this application;

[0031] Figure 6 This is a schematic diagram of a photovoltaic system provided in an embodiment of this application;

[0032] Figure 7 A schematic diagram of a power system provided in an embodiment of this application as an energy storage system;

[0033] Figure 8 A schematic diagram of a power supply system provided in an embodiment of this application;

[0034] Figure 9 A schematic diagram of another power supply system provided in an embodiment of this application;

[0035] Figure 10 A flowchart illustrating a power system protection method provided in this application embodiment;

[0036] Figure 11 A flowchart of another power system protection method provided in an embodiment of this application. Detailed Implementation

[0037] As energy storage and photovoltaic systems increasingly operate at higher voltage levels (some exceeding 1500V) and power systems with higher current ratings, ordinary fuses cannot provide rapid disconnection for these systems. Furthermore, solid-state composite switches in related technologies include mechanical switches, thus their breaking speed is limited by the mechanical switches, preventing rapid disconnection of power supply paths in high-voltage or high-current applications.

[0038] Therefore, this application provides a protection circuit to improve the speed of quickly disconnecting the power supply path in a new energy system. This protection circuit includes a semiconductor switching module and a detonating fuse connected in parallel, utilizing the advantages of both. Under normal operation, current flows through the detonating fuse, causing the semiconductor switching module to disconnect, thus avoiding conduction losses. Under abnormal operation, the semiconductor switching module conducts, diverting some of the current flowing through the detonating fuse, improving the detonating fuse's application capability in higher voltage systems. Because the semiconductor switching module diverts some energy, it facilitates a faster melting of the detonating fuse, providing protection. This application's parallel connection of the semiconductor switching module and the detonating fuse increases the detonating fuse's breaking time under abnormal operating conditions, thereby improving the reliability of the power supply system.

[0039] Since the power system is in normal operation, the semiconductor switching module is off and the exploding fuse is on. Therefore, the semiconductor switching module will not generate conduction loss. Compared with the case where there is only a semiconductor switching module but no exploding fuse, the conduction loss of the semiconductor switching module can be reduced, thus improving the efficiency of the power system.

[0040] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the embodiments of this application will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0041] See Figure 1 The figure is a schematic diagram of a power supply system provided in an embodiment of this application.

[0042] The power system provided in this application includes: a protection circuit and a controller 200; the protection circuit is connected in series between the DC source 300 and the subsequent circuit 400 of the power system; this application does not specifically limit the specific application scenario of the power system, and it can be applied to photovoltaic scenarios, energy storage scenarios, electric vehicle charging and discharging scenarios, or other power supply scenarios, etc.

[0043] The embodiments of this application do not specifically limit the type of the downstream circuit 400. It can be other circuits or loads, such as an inverter or an energy storage converter.

[0044] The protection circuit includes: semiconductor switch module 100 and explosive fuse Pyro Fuse.

[0045] The semiconductor switch module 100 and the explosive fuse Pyro Fuse are connected in parallel.

[0046] The controller 200 is used to control the semiconductor switch module 100 to disconnect and the explosive fuse Pyro Fuse to conduct when the system is in normal working condition; when the system is in abnormal working condition, it first controls the semiconductor switch module 100 to conduct and then controls the explosive fuse Pyro Fuse to disconnect.

[0047] The embodiments of this application do not specifically limit the abnormal working conditions. For example, one possible implementation is that the abnormal working conditions include any of the following: the voltage or current of the protection circuit exceeds the corresponding preset range, or a fault command is received from the host computer.

[0048] This application does not specifically limit the type of abnormal operating condition. One possible implementation involves detecting the current flowing through the protection circuit. When the current exceeds a preset range, the power system is considered to be in an abnormal operating condition, requiring protection measures, i.e., the power supply path is cut off. The preset range can be set according to the actual protection needs, for example, it can be set to a current range or a voltage range.

[0049] This application does not specifically limit the specific structure and type of the semiconductor switch module 100, as long as it exhibits switching characteristics, i.e., it can control the conduction and disconnection of the power supply path. For example, the semiconductor switch module 100 may include one semiconductor switch device or multiple semiconductor switch devices. The specific type of semiconductor switch device may be a metal-oxide-semiconductor field-effect transistor (MOS) or an insulated-gate bipolar transistor (IGBT).

[0050] The power supply system provided in this application embodiment features a parallel connection between a semiconductor switch module and an explosive fuse in the protection circuit. This allows them to work together to leverage their respective advantages when the power supply path needs to be cut off for protection. Because of the high voltage level, directly disconnecting the explosive fuse could cause arcing. Therefore, the semiconductor switch module is first turned on to divert energy and reduce the current flowing through the explosive fuse. Disconnecting the explosive fuse at this point prevents arcing. Furthermore, a smaller current allows for faster fuse disconnection, thus meeting safety regulations.

[0051] To further protect the semiconductor switching module, the power system and controller provided in this application embodiment are also used to control the semiconductor switching module to disconnect after the exploding fuse is disconnected in abnormal working conditions, which can reduce the conduction loss of the semiconductor switching module.

[0052] It should be understood that after the exploding fuse blows, the semiconductor switch module can remain in the on state without being disconnected. This reduces the control process, avoids frequent operation of the semiconductor switch module, protects its safety, and extends its lifespan.

[0053] See Figure 2 The image is a schematic diagram of an explosive fuse.

[0054] Figure 2 This is merely a schematic diagram of an explosive fuse, including a pyrotechnic switch and multiple fuses. The pyrotechnic switch is a controlled device that can be controlled to open, i.e., cut off the power supply. The left side of the pyrotechnic switch includes multiple fuses connected in parallel, namely Fuse1, Fuse1-2 to Fuse1-N. The right side of the pyrotechnic switch includes multiple fuses connected in parallel, namely Fuse2, Fuse2-2 to Fuse2-N.

[0055] The following describes several implementation methods of the protection circuit provided in the embodiments of this application, with reference to the accompanying drawings.

[0056] See Figure 3 The figure is a schematic diagram of a protection circuit provided in an embodiment of this application.

[0057] The power system provided in this application embodiment is described using a semiconductor switch module including a controllable switching device as an example. The semiconductor switch module includes: a first controllable switching device Q1.

[0058] The first controllable switching device Q1 is connected in parallel with the explosive fuse Pyro Fuse.

[0059] For example, Figure 3The provided protection circuit can be applied to photovoltaic systems. The first terminal of the first controllable switch Q1 is connected to the photovoltaic array, and the second terminal of Q1 is connected to the subsequent circuit. When the current flowing through the protection circuit exceeds a preset range, the first controllable switch Q1 is first turned on, and then the Pyro fuse is turned off. The current from the photovoltaic array flows through the first controllable switch Q1, which shares the current flowing through the Pyro fuse. Once the current flowing through the Pyro fuse is reduced, the Pyro fuse is then turned off. After the Pyro fuse is turned off, to save on the conduction loss of the first controllable switch Q1, it can be turned off again. Due to the reverse cutoff characteristic of the body diode of the first controllable switch Q1, the current from the photovoltaic array will not flow to the subsequent circuit.

[0060] Figure 3 The protection circuit shown cannot completely shut off the energy path if the energy transfer direction is from right to left when both the first controllable switch Q1 and the explosive fuse Pyro Fuse are disconnected. The following describes two other protection circuits provided in the embodiments of this application, which can achieve complete bidirectional shutdown of energy.

[0061] See Figure 4 The figure is a schematic diagram of a protection circuit provided in an embodiment of this application.

[0062] The power supply system provided in this application embodiment includes a semiconductor switching module comprising: a first controllable switching device Q1 and a second controllable switching device Q2; the first controllable switching device Q1 and the second controllable switching device Q2 are connected in series and then connected in parallel with a PyroFuse. The first controllable switching device Q1 and the second controllable switching device Q2 form a bidirectional switch, meaning that the current can flow in both directions. For example, both the first controllable switching device Q1 and the second controllable switching device Q2 are insulated gate bipolar transistors (IGBTs), the collector of Q1 is connected to the first terminal of the PyroFuse, the emitter of Q1 is connected to the emitter of Q2, and the collector of Q2 is connected to the second terminal of the PyroFuse.

[0063] Both the first controllable switching device Q1 and the second controllable switching device Q2 include their own body diodes. The body diodes of the first controllable switching device Q1 and the second controllable switching device Q2 are connected back-to-back or top-to-top, that is, the two body diodes are in opposite directions. Figure 4 The example used is a back-to-back connection.

[0064] The controller, in abnormal operating conditions, specifically controls the first controllable switch Q1 to open when the current flows from the DC source to the subsequent circuit, and controls the second controllable switch Q2 to open when the current flows from the subsequent circuit to the DC source. Under normal operating conditions, it controls one of the first controllable switch Q1 and the second controllable switch Q2 to turn on based on the current direction. For example, when the current flows from the DC source to the subsequent circuit, the first controllable switch Q1 is turned on, and the second controllable switch Q2 is turned off. The collector of Q1 is connected to the DC source, and the collector of Q2 is connected to the subsequent circuit. When the current flows from the subsequent circuit to the DC source, the second controllable switch Q2 is turned on, and the first controllable switch Q1 is turned off.

[0065] The power system provided in this application embodiment can be applied to photovoltaic systems or energy storage systems. Since in energy storage systems, the energy storage battery may be charging or discharging, and the current flows in two directions, it is possible to utilize… Figure 4 The protection circuit shown provides protection and completely shuts off bidirectional current.

[0066] For example, if the current flows from left to right, under normal power system conditions, the current flows through the Pyro Fuse, causing Q1 to trip. When the power system malfunctions, Q1 is turned on, and some current flows through the body diode of Q2 and Q1, again causing the Pyro Fuse to trip.

[0067] If the current flows from right to left, under normal power system operation, the current flows through the Pyro Fuse, causing Q2 to trip. When the power system malfunctions, Q2 is turned on, and some current flows through the body diode of Q1 and Q2, again causing the Pyro Fuse to trip.

[0068] See Figure 5 The figure is a schematic diagram of a protection circuit provided in an embodiment of this application.

[0069] The power supply system provided in this application embodiment includes a semiconductor switching module comprising: a first controllable switching device Q1, a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4.

[0070] The anode and cathode of the first diode D1 are connected to the first end of the Pyro Fuse and the cathode of the third diode D3, respectively. The anode of the third diode D3 is connected to the second end of the Pyro Fuse.

[0071] The cathode and anode of the fourth diode D4 are respectively connected to the first end of the Pyro Fuse and the anode of the second diode D2. The cathode of the second diode D2 is connected to the second end of the Pyro Fuse. The first and second ends of the first controllable switch Q1 are respectively connected to the cathode of the first diode D1 and the anode of the fourth diode D4.

[0072] The power system provided in this application embodiment can be applied to photovoltaic systems or energy storage systems. Since in energy storage systems, the energy storage battery may be charging or discharging, and the current flows in two directions, it is possible to utilize… Figure 5 The protection circuit shown provides protection and completely shuts off bidirectional current.

[0073] For example, if the current flows from left to right, when the power system is working normally, the current flows through the Pyro Fuse, causing Q1 to open. When the power system malfunctions, Q1 is turned on, and some current flows through D1, Q1, and D2, which then causes the Pyro Fuse to open.

[0074] If the current flows from right to left, under normal power system operation, the current flows through the Pyro Fuse, causing Q1 to trip. When the power system malfunctions, Q1 conducts, and some current flows through D3, Q1, and D4, again causing the Pyro Fuse to trip.

[0075] See Figure 6 The figure is a schematic diagram of a photovoltaic system provided in an embodiment of this application.

[0076] When the power system provided in this application embodiment is a photovoltaic system, the DC source is a photovoltaic array; when the DC source is a photovoltaic array, the downstream circuit in the power system is an inverter 500, that is, the power system also includes an inverter 500, and the protection circuit is connected between the photovoltaic array and the inverter 500.

[0077] In this embodiment, the power supply system includes two protection circuits as an example. The two protection circuits are: a first protection circuit and a second protection circuit.

[0078] The first protection circuit is connected between the positive terminal PV+ of the DC source and the inverter 500, and the second protection circuit is connected between the negative terminal PV- of the DC source and the inverter 500.

[0079] It should be understood that, for better protection, in the event of abnormal operation of the power system, both the first and second protection circuits operate simultaneously, protecting the power supply paths of both the positive and negative busbars. The specific operating procedures of the two protection circuits can be found in [link to relevant documentation]. Figure 5 The description will not be repeated here.

[0080] See Figure 7 The figure is a schematic diagram of the power system provided in the embodiment of this application as an energy storage system.

[0081] When the power system provided in this application embodiment is an energy storage system, the DC source is the energy storage battery 300. The power system also includes a downstream circuit, which is an energy storage converter 600. A protection circuit is connected between the energy storage battery 300 and the energy storage converter 600.

[0082] contrast Figure 6 and Figure 7 It can be observed that, Figure 7 The DC source and subsequent circuits differ in this design. The number and connection of the protection circuits are the same, and will not be described further here.

[0083] The energy storage converter 600 includes a soft start circuit, a DC contactor, and a DC / AC circuit. The soft start circuit includes a resistor and a switch. The soft start circuit and the DC contactor are connected in parallel between the DC / AC circuit and the protection circuit. When power is first applied, the soft start circuit is activated. When power is restored and normal operation is resumed, the soft start circuit is deactivated and the DC contactor is closed.

[0084] The working process of the controller control and protection circuit in the power system provided in this application embodiment is described below with reference to the accompanying drawings.

[0085] See Figure 8 The figure is a schematic diagram of a power supply system provided in an embodiment of this application.

[0086] The controller receives the current signal flowing through the protection circuit in real time. This signal can be acquired using a current sensor or current transformer and sent to the controller. This controller can be used in a photovoltaic system or an energy storage system.

[0087] The controller controls the operation of the protection circuit based on the magnitude of the current signal. For example, when the current signal exceeds a preset range, it confirms an abnormality in the power system, indicating an abnormal operating condition. In this case, control signal 2 is first sent to Q1 to turn it on, and then control signal 1 is sent to the Pyro Fuse to turn it off. However, after the Pyro Fuse turns off, to avoid continued conduction losses in Q1, Q1 can be turned off again. Of course, if conduction losses in Q1 are not considered, Q1 can also be left on without being turned off.

[0088] In addition, when the current in the power supply system is large, it exceeds the capacity of the semiconductor switching module. In order to protect the semiconductor switching module, the controller is also used to directly control the exploding fuse to disconnect when the voltage or current of the protection circuit exceeds a preset threshold. The preset threshold is greater than the maximum value of the preset range.

[0089] Another possible implementation, provided in this application embodiment, further includes: an absorption circuit and a clamping circuit connected in parallel across the semiconductor switching module; see also Figure 9 This figure is a schematic diagram of another power supply system provided in an embodiment of this application.

[0090] The power supply system provided in this application embodiment further includes an absorption circuit and a clamping circuit. The absorption circuit includes a resistor R and a capacitor C connected in series; the clamping circuit includes a varistor MOV or a Schottky diode. Figure 9 The clamping circuit is illustrated using a varistor MOV as an example.

[0091] The clamping circuit primarily clamps the voltage, stabilizing the voltage across the parallel-connected explosive fuse and semiconductor switching module to prevent large fluctuations and protect both. The absorption circuit absorbs large current surges, protecting the entire semiconductor switching module and the explosive fuse. Without an absorption circuit, the explosive fuse's activation could cause a large current surge to the semiconductor switching module, affecting its lifespan; similarly, the absence of an absorption circuit would also shorten the explosive fuse's lifespan when the semiconductor switching module operates.

[0092] Based on the power supply system provided in the above embodiments, this application also provides a protection method for the power supply system, which will be described in detail below with reference to the accompanying drawings.

[0093] See Figure 10 The figure is a flowchart of a power system protection method provided in an embodiment of this application.

[0094] The power system protection method provided in this application includes a protection circuit connected in series between the DC source and the subsequent circuit of the power system; the protection circuit includes a semiconductor switching module and an explosive fuse; the semiconductor switching module and the explosive fuse are connected in parallel.

[0095] S901: Under normal operating conditions, the control semiconductor switch module is disconnected, and the explosive fuse is turned on;

[0096] S902: In case of abnormal operation, first control the semiconductor switch module to turn on, and then detonate the fuse to disconnect.

[0097] The embodiments of this application do not specifically limit the abnormal working conditions. For example, abnormal working conditions include any of the following: the voltage or current of the protection circuit exceeds the corresponding preset range, or a fault command is received from the host computer.

[0098] The power system protection method provided in this application embodiment uses a semiconductor switch module and an explosive fuse connected in series in the protection circuit. This allows them to work together to leverage their respective advantages when the power supply path needs to be cut off for protection. Because of the high voltage level, directly disconnecting the explosive fuse could cause arcing. Therefore, first turning on the semiconductor switch module diverts energy, reducing the current flowing through the explosive fuse. Disconnecting the explosive fuse at this point prevents arcing. Furthermore, a smaller current allows for faster fuse disconnection, thus meeting safety requirements. This application embodiment connects the semiconductor switch module and the explosive fuse in parallel, which improves the breaking time of the explosive fuse under abnormal operating conditions, thereby enhancing the reliability of the power system.

[0099] Since the power system is in normal operation, the semiconductor switching module is off and the explosive fuse is on. This reduces the conduction loss of the semiconductor switching module and improves the efficiency of the power system compared to a situation where there is only a semiconductor switching module but no explosive fuse.

[0100] The following section, with reference to the accompanying drawings, describes the specific implementation process of a protection method.

[0101] See Figure 11 The figure is a flowchart of another power system protection method provided in an embodiment of this application.

[0102] S101: Controls the semiconductor switch module to disconnect; the explosive fuse is in the default on state.

[0103] S102: Collects the current flowing through the protection circuit.

[0104] S103: If the current flowing through the protection circuit is within the preset range, execute S102; otherwise, continue executing S104. If the current flowing through the protection circuit is within the preset range, it means that no protection action is required. Protection action is only required when the current flowing through the protection circuit exceeds the preset range.

[0105] S104: First, control the semiconductor switch module to turn on;

[0106] S105: Control the explosive fuse to disconnect. S104 is executed before S105, causing the semiconductor switching module to first conduct to divert current to the explosive fuse, reducing the current flowing through the explosive fuse, and then disconnecting the explosive fuse.

[0107] S106: Controls the semiconductor switching module to disconnect.

[0108] It should be understood that S106 is a non-essential step, and the semiconductor switching module can be disconnected without control.

[0109] In addition, when the current of the power supply system is large, it has exceeded the bearing capacity of the semiconductor switching module. In order to protect the semiconductor switching module, the protection method provided in this application embodiment further includes: when the voltage or current of the protection circuit exceeds a preset threshold, directly controlling the explosive fuse to disconnect, wherein the preset threshold is greater than the maximum value of a preset range.

[0110] Based on the power supply system and power supply system protection method provided in the above embodiments, this application also provides a protection circuit, which can be found in the power supply system embodiments described above. Figures 3-5 The protection circuit shown will not be described in detail here.

[0111] The protection circuit provided in this application includes: a semiconductor switch module and an explosive fuse; the semiconductor switch module and the explosive fuse are connected in parallel.

[0112] One possible implementation is that the semiconductor switch module includes: a first controllable switch device; the first controllable switch device is connected in parallel with an exploding fuse.

[0113] One possible implementation is that the semiconductor switch module includes: a first controllable switch device and a second controllable switch device; the first controllable switch device and the second controllable switch device are connected in series and then connected in parallel with an explosive fuse.

[0114] In one possible implementation, the semiconductor switch module includes: a first controllable switch device, a first diode, a second diode, a third diode, and a fourth diode; the anode and cathode of the first diode are respectively connected to the first end of an explosive fuse and the cathode of the third diode, and the anode of the third diode is connected to the second end of the explosive fuse; the cathode and anode of the fourth diode are respectively connected to the first end of the explosive fuse and the anode of the second diode, and the cathode of the second diode is connected to the second end of the explosive fuse; the first end and the second end of the first controllable switch device are respectively connected to the cathode of the first diode and the anode of the fourth diode.

[0115] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0116] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A power supply system characterized by comprising: The application relates to a power supply system, comprising: a controller and a protection circuit; the protection circuit is connected in series between a direct-current source of the power supply system and a subsequent circuit; the protection circuit comprises a semiconductor switch module and an explosion fuse; the semiconductor switch module and the explosion fuse are connected in parallel; the controller is used for sending a first signal to control the semiconductor switch module to be turned on and the explosion fuse to be turned off. The controller sends a second signal to control the semiconductor switch module to be turned off and the explosion fuse to be turned on. The controller sends the first signal when the voltage or current of the protection circuit exceeds a corresponding preset range or when a fault instruction sent by an upper computer is received. The second signal is that the voltage or current of the protection circuit is within the corresponding preset range and no fault instruction sent by the upper computer is received. The controller is further used for controlling the semiconductor switch module to be turned off after the explosion fuse is turned off. The semiconductor switch module comprises a first controllable switch device.

2. The power supply system according to claim 1, characterized by The first controllable switch device is connected in parallel with the explosion fuse.

3. The power supply system of claim 2, wherein The semiconductor switch module comprises a first controllable switch device and a second controllable switch device. The first controllable switch device and the second controllable switch device are connected in series and then connected in parallel with the explosion fuse.

4. The power supply system according to claim 3, characterized by The controller is used for sending a first signal to control the semiconductor switch module to be turned on, and specifically comprises: when the current direction is from the direct-current source to the subsequent circuit, the first controllable switch device is controlled to be turned off; when the current direction is from the subsequent circuit to the direct-current source, the second controllable switch device is controlled to be turned off; the controller is used for sending a second signal to control the semiconductor switch module to be turned off, and specifically comprises: one of the first controllable switch device and the second controllable switch device is controlled to be turned on according to the current direction.

5. The power supply system according to any one of claims 1 to 4, characterized by, The semiconductor switch module comprises a first controllable switch device, a first diode, a second diode, a third diode and a fourth diode. The anode and cathode of the first diode are connected with a first end of the explosion fuse and the cathode of the third diode respectively, and the anode of the third diode is connected with a second end of the explosion fuse.

6. The power supply system according to any one of claims 2 to 4, characterized by The cathode and anode of the fourth diode are connected with the first end of the explosion fuse and the anode of the second diode respectively, the cathode of the second diode is connected with the second end of the explosion fuse, and the first end and second end of the first controllable switch tube are connected with the cathode of the first diode and the anode of the fourth diode respectively. The direct-current source is an energy storage battery or a photovoltaic array. When the direct-current source is an energy storage battery, the power supply system further comprises an energy storage converter, and the protection circuit is connected between the energy storage battery and the energy storage converter.

7. The power supply system according to claim 1 or 2, characterized by When the direct-current source is a photovoltaic array, the power supply system further comprises an inverter, and the protection circuit is connected between the photovoltaic array and the inverter. The power supply system comprises two protection circuits, i.e., a first protection circuit and a second protection circuit. The first protection circuit is connected between the positive electrode of the direct-current source and the subsequent circuit, and the second protection circuit is connected between the negative electrode of the direct-current source and the subsequent circuit.

8. The power supply system according to any one of claims 1 to 7, characterized by, ​ ​ ​ 9. The power supply system of claim 8, wherein, ​ ​ 10. The power supply system according to any one of claims 1 to 9, characterized by, The controller is further configured to directly control the explosion fuse to be disconnected when the voltage or current of the protection circuit exceeds a preset threshold value, the preset threshold value being greater than a maximum value of the preset range.

11. The power supply system according to any one of claims 1 to 10, characterized by Further comprising: An absorption circuit and a clamping circuit connected in parallel across the semiconductor switch module; The absorption circuit comprises a resistor and a capacitor connected in series; and the clamping circuit comprises a varistor or a Schottky diode.

12. A protection method of a power supply system, characterized by, The power supply system comprises a protection circuit connected in series between a direct current source and a subsequent circuit of the power supply system; the protection circuit comprises a semiconductor switch module and an explosion fuse; the semiconductor switch module and the explosion fuse are connected in parallel; A first signal is sent to control the semiconductor switch module to be turned on and the explosion fuse to be disconnected.

13. The protection method according to claim 12, characterized in that, Further comprising: a second signal is sent to control the semiconductor switch module to be turned off and the explosion fuse to be turned on; The first signal is sent when the voltage or current of the protection circuit exceeds a corresponding preset range or a fault instruction sent by an upper computer is received. The second signal is sent when the voltage or current of the protection circuit is within the corresponding preset range and no fault instruction sent by the upper computer is received.

14. The protection method of claim 12, wherein, Further comprising: After the explosion fuse is controlled to be disconnected, the semiconductor switch module is controlled to be turned off.

15. The protection method of claim 11, wherein, Further comprising: The explosion fuse is directly controlled to be disconnected when the voltage or current of the protection circuit exceeds a preset threshold value, the preset threshold value being greater than a maximum value of the preset range.

16. A protection circuit, characterized by Comprising: A semiconductor switch module and an explosion fuse; The semiconductor switch module and the explosion fuse are connected in parallel.

17. The protection circuit of claim 16, wherein, The semiconductor switch module comprises a first controllable switching device. The first controllable switching device is connected in parallel with the explosion fuse.

18. The protection circuit of claim 16, wherein, The semiconductor switch module comprises a first controllable switching device and a second controllable switching device. The first controllable switching device and the second controllable switching device are connected in series and then connected in parallel with the explosion fuse.

19. The protection circuit of claim 16, wherein, The semiconductor switch module comprises a first controllable switching device, a first diode, a second diode, a third diode and a fourth diode. An anode and a cathode of the first diode are connected to a first end of the explosion fuse and a cathode of the third diode, respectively; and an anode of the third diode is connected to a second end of the explosion fuse. A cathode and an anode of the fourth diode are connected to the first end of the explosion fuse and an anode of the second diode, respectively; a cathode of the second diode is connected to the second end of the explosion fuse; and a first end and a second end of the first controllable switching tube are connected to the cathode of the first diode and the anode of the fourth diode, respectively.

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