A method and device for controlling a circuit breaker and a circuit breaker

Abstract

The present invention discloses a control method, device and circuit breaker of a circuit breaker. After receiving a heartbeat signal, N main switch tubes are turned on, so that N photovoltaic modules can output direct current through the N corresponding main switch tubes. If a processor has an abnormal power supply voltage after the N main switch tubes are turned on, that is, the power supply voltage of the processor in the circuit breaker is less than its own first undervoltage protection voltage, the N bypass switch tubes are controlled to be turned on and the N main switch tubes are controlled to be turned off, so as to separate the N photovoltaic modules corresponding to the circuit breaker and the N main switch tubes from multiple photovoltaic module groups connected in series to an inverter, so that the photovoltaic module groups corresponding to other circuit breakers can normally output direct current voltage to the inverter, so that the inverter can normally output alternating current to be incorporated into the power grid, so that the photovoltaic system can operate normally, and the reliability of the photovoltaic system is improved.

Description

Technical Field

[0001] The present invention relates to the field of safety protection of photovoltaic power generation systems, and in particular to a control method and device for a circuit breaker, and a circuit breaker. Background Art

[0002] Due to the renewable and clean nature of solar energy, photovoltaic grid-connected power generation technology has rapidly developed. A typical photovoltaic system consists of multiple photovoltaic modules connected in series. These modules are connected to an inverter via DC cables. The inverter converts the high-voltage DC power output from these modules into high-voltage AC power for integration into the power grid. Each photovoltaic module group consists of N modules, where N is a positive integer, and the N modules are connected in series.

[0003] In the prior art, in order to ensure the safety of power supply to photovoltaic systems, inverters are usually equipped with arc protection. Specifically, when an arc is detected, the inverter is controlled to stop working. However, after the inverter stops working, the DC cables connected to the output ends of multiple photovoltaic module groups will still output DC high voltage electricity, which may cause personal danger or fire accidents.

[0004] To address the aforementioned technical issues, conventional technology incorporates a circuit breaker at the output of each PV module. The circuit breaker's output is connected in series to the inverter. In the event of an arc, the circuit breaker is controlled to shut down, reducing the DC voltage on the DC cable and preventing personal injury and safety incidents. However, since multiple circuit breakers are connected in series, if one malfunctions, each PV module group will be unable to output DC power to the DC cable. Consequently, the inverter will be unable to integrate AC power into the grid, causing malfunction in the PV system. Summary of the Invention

[0005] The object of the present invention is to provide a control method, device and circuit breaker for a circuit breaker. When the power supply voltage of a processor in the circuit breaker is lower than its own first undervoltage protection voltage, the circuit breaker controls N bypass switch tubes to be turned on and controls N main switch tubes to be turned off, so as to separate the N photovoltaic modules and N main switch tubes corresponding to the circuit breaker from multiple photovoltaic module groups connected in series to an inverter, so that the photovoltaic module groups corresponding to other circuit breakers can normally output DC voltage to the inverter, thereby allowing the inverter to normally output AC power to be connected to the power grid, so that the photovoltaic system can operate normally, and the reliability of the photovoltaic system is improved.

[0006] To solve the above technical problems, the present invention provides a method for controlling a circuit breaker, which is applied to a processor in the circuit breaker, wherein the circuit breaker includes N main switches corresponding to N photovoltaic modules and N bypass switches corresponding to the N photovoltaic modules.

[0007] The positive power terminal of the processor is connected to the positive output terminal of the first photovoltaic assembly, the negative power terminal of the processor is connected to the negative output terminal of the i-th photovoltaic assembly, the first end of the first main switch tube is the positive output terminal of the shutdown device, the second end of the i-th main switch tube is connected to the positive output terminal of the i-th photovoltaic assembly, the first end of the (i+1)th main switch tube is connected to the negative output terminal of the i-th photovoltaic assembly, the negative output terminal of the N-th photovoltaic assembly is the negative output terminal of the shutdown device, the first end of the bypass switch tube is connected to the first end of the corresponding main switch tube, and the second end of the bypass switch tube is connected to the negative output terminal of the corresponding photovoltaic assembly, N≥i≥1, and N and i are both integers;

[0008] The control method includes:

[0009] After receiving the heartbeat signal, controlling the N main switch tubes to be turned on;

[0010] Determining whether the power supply voltage of the processor itself is less than a first undervoltage protection voltage;

[0011] If so, the N main switch tubes are controlled to be disconnected, and the N bypass switch tubes are controlled to be closed.

[0012] Preferably, before determining whether the power supply voltage of the processor itself is less than the first undervoltage protection voltage, the method further includes:

[0013] Determining whether the power supply voltage of the processor itself is less than a second undervoltage protection voltage, the second undervoltage protection voltage being less than the first undervoltage protection voltage;

[0014] If the supply voltage is not less than the second undervoltage protection voltage, then entering the step of determining whether the supply voltage of the processor itself is less than the first undervoltage protection voltage;

[0015] If the supply voltage is lower than the second undervoltage protection voltage, the processor is controlled to power off, and after receiving the power-on instruction, it is controlled to power on, and the step of determining whether the supply voltage of the processor itself is lower than the second undervoltage protection voltage is entered.

[0016] Preferably, the bypass switch tube is a transistor field effect tube (MOS tube), and the MOS tube includes a body diode;

[0017] After controlling the N main switch tubes to be disconnected, the method further includes:

[0018] Obtaining a bypass current passing through the bypass switch tube;

[0019] Determining whether the bypass current is greater than a preset current;

[0020] If so, the step of controlling the N bypass switches to be closed is entered.

[0021] Preferably, determining whether the bypass current is greater than a preset current includes:

[0022] Determining whether the bypass current is continuously greater than the preset current within a first preset time;

[0023] If the bypass current is continuously greater than the preset current within the first preset time, the step of controlling the N bypass switches to be closed is entered.

[0024] Preferably, after controlling the N main switch tubes to be turned off and controlling the N bypass switch tubes to be turned on, the method further includes:

[0025] Determining whether the closing time of the N bypass switch tubes reaches a second preset time;

[0026] If so, the N bypass switch tubes are controlled to be turned off, and the step of controlling the N main switch tubes to be turned on is entered.

[0027] Preferably, controlling the N main switching tubes to be turned on includes:

[0028] Controlling the N main switching tubes to conduct at staggered peaks;

[0029] Controlling the N bypass switch tubes to be disconnected includes:

[0030] The order of controlling the N bypass switch tubes to be turned off is the same as the order of controlling the corresponding N main switch tubes to be turned on at staggered times.

[0031] Preferably, after determining whether the power supply voltage of the processor itself is less than the first undervoltage protection voltage, the method further includes:

[0032] If the power supply voltage thereof is not less than the first undervoltage protection voltage thereof, obtaining the working information of the N photovoltaic assemblies;

[0033] Determining whether there is any photovoltaic component operating abnormally among the N photovoltaic components based on the operating information;

[0034] If there is a photovoltaic component that is working abnormally, the main switch tube corresponding to the photovoltaic component that is working abnormally is controlled to be disconnected and the corresponding bypass switch tube is controlled to be turned on.

[0035] To solve the above technical problems, the present application further provides a control device for a circuit breaker, comprising:

[0036] memory for storing computer programs;

[0037] The processor is configured to implement the above-mentioned method for controlling the circuit breaker when executing the computer program.

[0038] To solve the above technical problems, the present application further provides a circuit breaker, comprising the above-mentioned circuit breaker control device, N main switch tubes corresponding to N photovoltaic modules, and N bypass switch tubes corresponding to the N photovoltaic modules.

[0039] The positive power terminal of the processor is connected to the positive output terminal of the first photovoltaic assembly, the negative power terminal of the processor is connected to the negative output terminal of the i-th photovoltaic assembly, the first end of the first main switch tube is the positive output terminal of the circuit breaker, the second end of the i-th main switch tube is connected to the positive output terminal of the i-th photovoltaic assembly, the first end of the i+1-th main switch is connected to the negative output terminal of the i-th photovoltaic assembly, the negative output terminal of the N-th photovoltaic assembly is the negative output terminal of the circuit breaker, the first end of the bypass switch tube is connected to the first end of the corresponding main switch tube, and the second end of the bypass switch tube is connected to the negative output terminal of the corresponding photovoltaic assembly, N≥i≥1, and N and i are both integers.

[0040] Preferably, it further includes a diode, a first capacitor and a second capacitor;

[0041] The anode of the diode is connected to the positive output terminal of the first photovoltaic assembly, the cathode of the diode is connected to the first end of the first capacitor and the positive power supply terminal of the processor, the second end of the first capacitor is connected to the negative output terminal of the first photovoltaic assembly and the first end of the second capacitor, and the first end of the second capacitor is connected to the power output terminal of the processor and the power supply terminal of the electrical device in the circuit breaker;

[0042] The processor is further configured to convert the voltage of the positive terminal of its own power supply to supply power to the electrical equipment in the circuit breaker.

[0043] The present application provides a control method, device, and circuit breaker for a circuit breaker. After receiving a heartbeat signal, N main switch tubes are turned on, so that N photovoltaic modules can output direct current through the N corresponding main switch tubes. If, after the N main switch tubes are turned on, a processor has an abnormal power supply voltage, that is, the power supply voltage of the processor in the circuit breaker is lower than its own first undervoltage protection voltage, the N bypass switch tubes are controlled to be turned on, and the N main switch tubes are controlled to be turned off, so as to separate the N photovoltaic modules corresponding to the circuit breaker and the N main switch tubes from multiple photovoltaic module groups connected in series to the inverter, so that the photovoltaic module groups corresponding to other circuit breakers can normally output direct current voltage to the inverter, so that the inverter can normally output alternating current to be connected to the power grid, so that the photovoltaic system can operate normally, thereby improving the reliability of the photovoltaic system. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the prior art and the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0045] Figure 1 A schematic flow chart of a method for controlling a circuit breaker provided by the present invention;

[0046] Figure 2 A specific implementation circuit diagram of a circuit breaker provided by the present invention;

[0047] Figure 3 A control timing diagram of the first type of circuit breaker provided by the present invention;

[0048] Figure 4 A control timing diagram of the corresponding shutdown device when the processor provided by the present invention is not powered off;

[0049] Figure 5 A schematic diagram of the control flow of the bypass switch tube when the processor provided by the present invention is not powered off;

[0050] Figure 6 A control timing diagram of the corresponding shutdown device when the processor provided by the present invention is powered off;

[0051] Figure 7 A schematic diagram of the control flow of the bypass switch tube when the processor is powered off provided by the present invention;

[0052] Figure 8 This is a structural block diagram of a control device for a circuit breaker provided by the present invention. DETAILED DESCRIPTION

[0053] The core of the present invention is to provide a control method, device and circuit breaker for a circuit breaker. When the power supply voltage of the processor in the circuit breaker is lower than its own first undervoltage protection voltage, the circuit breaker controls N bypass switch tubes to be turned on and controls N main switch tubes to be turned off, so as to separate the N photovoltaic modules and N main switch tubes corresponding to the circuit breaker from multiple photovoltaic module groups connected in series to the inverter, so that the photovoltaic module groups corresponding to other circuit breakers can normally output DC voltage to the inverter, thereby allowing the inverter to normally output AC power to be connected to the power grid, so that the photovoltaic system can operate normally, thereby improving the reliability of the photovoltaic system.

[0054] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0055] Please refer to Figure 1 , Figure 1 This is a flow chart of a control method for a circuit breaker provided by the present invention. The control method is applied to a processor in the circuit breaker. The circuit breaker includes N main switches corresponding to N photovoltaic modules and N bypass switches corresponding to N photovoltaic modules.

[0056] The positive power terminal of the processor is connected to the positive output terminal of the first photovoltaic assembly, the negative power terminal of the processor is connected to the negative output terminal of the i-th photovoltaic assembly, the first end of the first main switch tube is connected to the positive output terminal of the shutdown device, the second end of the i-th main switch tube is connected to the positive output terminal of the i-th photovoltaic assembly, the first end of the (i+1)th main switch tube is connected to the negative output terminal of the i-th photovoltaic assembly, the negative output terminal of the N-th photovoltaic assembly is connected to the negative output terminal of the shutdown device, the first end of the bypass switch tube is connected to the first end of the corresponding main switch tube, and the second end of the bypass switch tube is connected to the negative output terminal of the corresponding photovoltaic assembly, N ≥ i ≥ 1, and N and i are both integers;

[0057] The control method includes:

[0058] S11: After receiving the heartbeat signal, control N main switches to turn on;

[0059] S12: Determine whether the processor's own power supply voltage is less than the first undervoltage protection voltage;

[0060] S13: If yes, control the N main switch tubes to be turned off, and control the N bypass switch tubes to be turned on.

[0061] Considering that multiple photovoltaic module groups are connected in series through circuit breakers to output DC power, and then the inverter converts the DC power into AC power and integrates it into the grid, the stable operation of the circuit breakers plays a vital role in the stable operation of the entire photovoltaic system. Specifically, if one of the circuit breakers fails, all photovoltaic modules will be unable to output DC power to the DC cable, and the entire photovoltaic system will be unable to integrate AC power into the grid.

[0062] In order to solve the above technical problems, the design idea of ​​this application is: to design a control method for a circuit breaker to ensure that the circuit breaker can work normally and stably, or to isolate the faulty circuit breaker from multiple photovoltaic component groups connected in series, so that other photovoltaic component groups can output DC power to the DC cable through the corresponding circuit breaker, so that the inverter can still convert the DC power on the DC cable into AC power to be connected to the power grid, thereby realizing the normal operation of the photovoltaic system.

[0063] Based on this, the present application provides a control method for controlling the operation of a circuit breaker based on the supply voltage of a processor to ensure the normal operation of a photovoltaic system. Specifically, the supply voltage of the processor is the direct current output by several photovoltaic modules in the corresponding photovoltaic module group. Upon receiving a heartbeat signal from the system controller, the corresponding N main switches are turned on. At this time, the direct current output by the photovoltaic modules not only powers the processor but also outputs the direct current to the DC cable through the corresponding main switches. The conduction of the N main switches may reduce the supply voltage of the processor, possibly reaching the processor's first undervoltage protection voltage, causing the processor to operate abnormally, which may make the control circuit breaker unreliable. Therefore, in the present application, when the supply voltage of the processor is lower than its own first undervoltage protection voltage, the corresponding N switches are controlled to be disconnected and the corresponding N bypass switches are controlled to be closed, so that the N bypass switches separate the photovoltaic module group consisting of N photovoltaic modules from multiple photovoltaic module groups connected in series, so that the other photovoltaic module groups can normally output direct current to the DC cable, thereby ensuring the normal operation of the photovoltaic system.

[0064] It should be noted that the first undervoltage protection voltage in this application is a protection voltage to protect the normal operation of the processor. The purpose of controlling the N main switch tubes to be turned off is to enable the power supply voltage of the processor to recover so that the processor can work normally.

[0065] Please refer to Figure 2 and Figure 3 , Figure 2 A specific implementation circuit diagram of a circuit breaker provided by the present invention, Figure 3 This is a control timing diagram of the first type of circuit breaker provided by the present invention.

[0066] As a preferred embodiment, it further includes a diode D1, a first capacitor C1 and a second capacitor C2;

[0067] The anode of the diode D1 is connected to the positive output terminal of the first photovoltaic module, the cathode of the diode D1 is connected to the first end of the first capacitor C1 and the positive power terminal of the processor, the second end of the first capacitor C1 is connected to the negative output terminal of the first photovoltaic module and the first end of the second capacitor C2, and the first end of the second capacitor C2 is connected to the power output terminal of the processor and the power terminal of the electrical device in the circuit breaker.

[0068] The processor is further configured to convert the voltage at the positive terminal of its own power supply to supply power to the power-consuming device in the circuit breaker.

[0069] Specifically, the voltage output by the photovoltaic module charges the first capacitor C1 through the diode D1. The voltage of the first capacitor C1 serves as the power supply voltage for the processor. Similarly, the power output terminal of the processor supplies power to the second capacitor C2. The voltage at the first terminal of the second capacitor C2 can power other electrical devices.

[0070] In addition, when the photovoltaic module does not output voltage, since the capacitor itself has the ability to store energy, even if the photovoltaic module does not output voltage, the first capacitor C1 can still power the processor for a period of time to ensure that the processor is not disconnected from power. Similarly, the second capacitor C2 can also ensure that the electrical equipment it powers can operate normally for a period of time.

[0071] Typically, a processor steps down its own supply voltage to power low-voltage devices. Therefore, the corresponding first capacitor C1 is a capacitor with a relatively large capacity, a relatively large package size, and a relatively high cost. For example, the voltage at the first end of the first capacitor C1 is approximately 100 volts, while the capacity, package size, and cost of the second capacitor C2 are relatively large. For example, the voltage at the first end of the second capacitor C2 is approximately 20 volts. In this case, since the power supply for the second capacitor C2 primarily comes from the first capacitor C1 when the photovoltaic module is not outputting voltage, the capacitance stored in the first capacitor C1 not only powers the processor but also powers the electrical devices connected to the processor's power output. At this time, we can adapt to make the capacity of the second capacitor C2 slightly larger (for example, increase the voltage at the first end of the second capacitor C2 to 25 volts) and the capacity of the first capacitor C1 slightly smaller (for example, reduce the voltage at the first end of the first capacitor C1 to 80 V). In this way, the second capacitor C2 stores more energy and takes less energy from the first capacitor C1. The capacity of the first capacitor C1 can be set smaller, which can greatly reduce the packaging volume and cost of the first capacitor C1 and the second capacitor C2.

[0072] In addition, based on the above embodiments: the processor in the present application can be a single processor or can include two separate processors. For example, when the processor includes a first processor and a second processor, when the number of photovoltaic modules corresponding to the shutdown device is 2 (for the convenience of describing the present invention, the following embodiments are all described with the number of photovoltaic modules, the number of main switch tubes, and the number of bypass switch tubes being 2), as Figure 2 and Figure 3 As shown, Vin2+ is the voltage output by the first photovoltaic component, VIN is the power supply voltage of the processor, specifically the power supply voltage of the first processor, that is, the capacitance of the first end of the first capacitor C1, V2 is the power supply voltage output by the processor, specifically the power supply voltage of the second processor, that is, the voltage of the first end of the second capacitor C2, IN_EN is the internal logic signal, Transmitter_ON is the heartbeat signal, and Trans_SET is the start signal sent by the second processor to the first processor after receiving the heartbeat signal. At this time, correspondingly, the first processor is specifically used to control the N main switch tubes to turn on after receiving the start signal, and when no start signal is received, control the N main switch tubes to turn off and control the N bypass switch tubes to close.

[0073] In summary, after N main switch tubes are turned on, if the processor has an abnormal power supply voltage, that is, the power supply voltage of the processor in the circuit breaker is lower than its own first under-voltage protection voltage, the present application controls N bypass switch tubes to be turned on and controls N main switch tubes to be turned off, so as to separate the N photovoltaic components corresponding to the circuit breaker and the N main switch tubes from the multiple photovoltaic component groups connected in series to the inverter, so that the photovoltaic component groups corresponding to other circuit breakers can normally output DC voltage to the inverter, so that the inverter can normally output AC power to be connected to the power grid, so that the photovoltaic system can operate normally, thereby improving the reliability of the photovoltaic system.

[0074] Based on the above embodiment:

[0075] As a preferred embodiment, the bypass switch tube is a MOS (Metal-Oxide-Semiconductor Field-Effect Transistor) tube, and the MOS tube includes a body diode D1;

[0076] After controlling N main switch tubes to be disconnected, the following steps are also included:

[0077] Obtaining the bypass current passing through the bypass switch tube;

[0078] Determine whether the bypass current is greater than the preset current;

[0079] If so, the process proceeds to the step of controlling N bypass switches to close.

[0080] Specifically, the bypass switch tube in this embodiment can be, but is not limited to, a MOS tube. When it is a MOS tube, since the MOS tube includes a body diode D1, after the main switch tube is turned off, a bypass current will pass through the body diode D1 in the MOS tube. However, if the bypass current is too large, the body diode D1 may be severely heated, which may damage the MOS tube.

[0081] In order to solve the above technical problems, the present application controls the bypass switch tube to be turned on when the bypass current is greater than the preset current, so as to avoid serious heating of the MOS tube and ensure the safety of the system.

[0082] As a preferred embodiment, determining whether the bypass current is greater than a preset current includes:

[0083] Determining whether the bypass current is continuously greater than a preset current within a first preset time;

[0084] If the bypass current is continuously greater than the preset current within the first preset time, the step of controlling the N bypass switches to be closed is entered.

[0085] The control method in the present application is provided with a first preset time to ensure the stability of the bypass circuit being greater than the preset current. That is, the N bypass switch tubes are controlled to close only when the bypass current is stably greater than the preset current within the first preset time.

[0086] Specifically, considering that the bypass current may be greater than the preset current only for a short period of time due to interference or other factors, if the bypass current is greater than the preset current, directly controlling the operation of N bypass switches may cause malfunction or cause the bypass switches to operate frequently, which may cause damage to the circuit breaker.

[0087] Therefore, a first preset time is set in the present application to ensure the stability of the bypass current judgment, to ensure the reliability of the system operation, and to avoid damage to the switch tube in the system.

[0088] As a preferred embodiment, after controlling the N main switch tubes to be disconnected and controlling the N bypass switch tubes to be closed, the method further includes:

[0089] Determine whether the closing time of the N bypass switch tubes reaches a second preset time;

[0090] If so, the N bypass switch tubes are controlled to be turned off, and the step of controlling the N main switch tubes to be turned on is entered.

[0091] After controlling the bypass switches to turn on, in order to restore the processor's supply voltage to a voltage sufficient for normal operation, and to determine whether the processor's supply voltage has recovered to a normal operating voltage, this embodiment employs the following method: after entering bypass mode (N bypass switches are turned on and N main switches are turned off) for a second preset time, the bypass mode is exited, and the main switches are turned on and the bypass switches are turned off. If the processor's supply voltage is normal at this point, the entire circuit breaker enters normal operation mode; otherwise, it re-enters bypass mode. In other words, this embodiment intermittently determines whether the circuit breaker has exited bypass mode.

[0092] As a preferred embodiment, controlling N main switches to be turned on includes:

[0093] Control N main switch tubes to conduct at staggered peaks;

[0094] Control N bypass switch tubes to disconnect, including:

[0095] The order of controlling the N bypass switch tubes to be turned off is the same as the order of controlling the corresponding N main switch tubes to be turned on at staggered times.

[0096] Specifically, to avoid shoot-through damage, if N main switches are turned on at the same time, the voltage on the bus and the current on each main switch will suddenly increase. At this time, the sudden voltage or current change may cause damage to the photovoltaic system.

[0097] To address the above technical issues, this application controls the N main switches to be turned on at staggered peaks, so that the voltage or current gradually increases, thereby avoiding damage to the photovoltaic system. The application does not impose any specific restrictions on the timing of the staggered conduction of the N main switches. Correspondingly, the N bypass switches are controlled to be turned off at staggered peaks.

[0098] Specifically, when N is 2, that is, one circuit breaker corresponds to two photovoltaic modules, two main switch tubes and two bypass switch tubes, if the main switch tube and the bypass switch tube in this application are NMOS tubes, Figure 2 and Figure 3 As shown, Figure 3 In the figure, Bypass_C is the bypass current, Ith_1 is the preset current, IN3 is the internal logic signal, g1, g2, g3 and g4 are the control signals of M1, M2, M3 and M4 respectively, where M1, M2, M3 and M4 are turned on when the control signal is high. Figure 3It can be seen that when the bypass current is greater than the preset current Td3 (first preset time), IN3 is high level. If the corresponding main switch is off, the corresponding bypass switch is turned on. Specifically, the level of g4 is determined by the logic of IN3 and g3, and the level of g2 is determined by the logic of IN3 and g1. In addition, Figure 6 It can be seen that M3 is turned on T4 earlier than M1 (peak shifting time), and the corresponding bypass switch tube M4 is turned off T4 earlier than M2.

[0099] When using the intermittent startup method, when the bypass switch tube is turned off at off-peak, the time when the bypass switch tube is turned off is Td2 hours earlier than the time when the corresponding main switch tube is turned on next time. It can also be other times, and this application does not make any special restrictions here.

[0100] In summary, the method of this embodiment can detect whether the processor has resumed normal operation, and when it is working normally, control the photovoltaic component group corresponding to the shutdown device to output DC power normally; when it is still abnormal, control it to enter the bypass mode.

[0101] As a preferred embodiment, before determining whether the power supply voltage of the processor itself is less than the first undervoltage protection voltage, the method further includes:

[0102] Determining whether the power supply voltage of the processor itself is less than a second undervoltage protection voltage, and the second undervoltage protection voltage is less than the first undervoltage protection voltage;

[0103] If the supply voltage is not less than the second undervoltage protection voltage, then entering the step of determining whether the supply voltage of the processor itself is less than the first undervoltage protection voltage;

[0104] If the supply voltage is lower than the second undervoltage protection voltage, the processor is controlled to power off, and after receiving the power-on instruction, it is controlled to power on, and then enters the step of determining whether the supply voltage of the processor itself is lower than the second undervoltage protection voltage.

[0105] Specifically, the first undervoltage protection voltage is only for recovering the power supply voltage of the processor. The first undervoltage protection voltage is a voltage that will not cause the processor to power off. After reaching the second undervoltage protection voltage, the processor will be controlled to power off. After power off, the power-off time of the processor will be shortened as much as possible, so that the processor can be powered on as soon as possible.

[0106] In addition, when the processor includes a first processor and a second processor, the first undervoltage protection voltage is a voltage that prevents the first processor from being powered off. At this time, the first processor U1 can be powered all the time, thereby achieving control over the entire system.

[0107] Please refer to Figure 4 , Figure 4The control timing diagram of the corresponding shutdown device when the processor provided by the present invention is not powered off, and the logic of the power supply control of the first end of the second capacitor C2 is controlled by the first undervoltage protection voltage so that the processor (specifically the first processor) does not power off, so that the bypass operation is always working during the first processor's power-on process. In order to maintain the power supply voltage VIN of the first processor, and at the same time make the control of g1 last for T8 time, the delay of T8 time is to take into account the drop of VIN voltage when M1 is turned on. When it drops to the undervoltage protection voltage of U1, g1 is controlled to be low level to turn off M1, so that the input voltage Vin 2+ rises, and the opening process is restarted to turn on the bypass switch tube. Please refer to Figure 5 , Figure 5 This is a schematic diagram of the control flow of the bypass switch tube when the processor provided by the present invention is not powered off. The circuit breaker starts after power is applied, detects the bypass current Bypass_C, and detects the control signal level of the bypass switch tube. If it is at a low level, the circuit breaker exits the bypass mode and continues to detect the bypass current. If it is at a high level, it indicates that the bypass switch tube is conducting at this time. At this time, the bypass switch tube is controlled. If the set time t7 has not been reached, the above process is repeated. After reaching t7, the bypass switch tubes M2 and M4 are turned off, and the main switch tubes M1 and M3 are turned on. If the power supply VIN of the main control chip U1 drops to the undervoltage protection value, U1 restarts the control mode. If the power supply VIN of the main control chip U1 remains stable and does not drop to the undervoltage protection value, the circuit breaker exits the bypass control mode.

[0108] Please refer to Figure 6 , Figure 6 For the control timing diagram of the shutdown device corresponding to the power failure of the processor provided by the present invention, please refer to Figure 7 , Figure 7 This is a schematic diagram of the control flow of the bypass switch tube when the processor is powered off provided by the present invention. Figure 4 and Figure 5 The process is similar, except that in the final step, if the power supply VIN of the main control chip U1 drops to the second undervoltage protection voltage, the first processor will lose power. The first processor will then be powered back on and the bypass control mode will be restarted. If the power supply VIN of the main control chip U1 remains stable, the bypass control mode will be exited.

[0109] As a preferred embodiment, after determining whether the power supply voltage of the processor itself is less than the first undervoltage protection voltage, the method further includes:

[0110] If its own power supply voltage is not less than its own first undervoltage protection voltage, then obtain the working information of N photovoltaic modules;

[0111] Determine whether there is any abnormal photovoltaic component among the N photovoltaic components based on the working information;

[0112] If there is a photovoltaic component that is working abnormally, the main switch tube corresponding to the photovoltaic component that is working abnormally is controlled to be disconnected and the corresponding bypass switch tube is controlled to be turned on.

[0113] Considering that there may be short board problems such as shading in the photovoltaic module corresponding to the circuit breaker, it may cause abnormal voltage and current output by the module, thereby affecting the operation of the entire photovoltaic system.

[0114] In order to solve the above technical problems, in this application, when the photovoltaic module outputs direct current to the bus through the corresponding main switch tube, the working information of each photovoltaic module is also obtained, and whether the corresponding photovoltaic module is abnormal is judged based on it. If abnormal, the corresponding bypass switch tube is controlled to be turned on to short-circuit the abnormal photovoltaic module and the main switch tube, and then separate it from the photovoltaic module group corresponding to the circuit breaker, so that other photovoltaic modules in the photovoltaic module group can output direct current normally through the turned-on bypass switch tube.

[0115] Specifically, obtaining the working information of the photovoltaic component may include, but is not limited to, obtaining the output voltage and / or working current of the photovoltaic component. When its output voltage is within a preset voltage range and / or its output current is within a preset current range, it indicates that the corresponding photovoltaic component is working normally. When it is no longer within the corresponding range, it indicates that the corresponding photovoltaic component is working abnormally.

[0116] In summary, the above implementation method can separate the abnormally working photovoltaic module from the photovoltaic module group corresponding to the switch, so that other photovoltaic modules in the photovoltaic module group can output voltage to the DC bus normally, thereby ensuring the normal operation of the photovoltaic system.

[0117] In addition, it should be noted that all logic controls in this application can be implemented not only using software algorithms, but also through hardware forms such as AND or OR gates, and this application does not make any special limitations here.

[0118] Please refer to Figure 8 , Figure 8 This is a structural block diagram of a control device for a circuit breaker provided by the present invention, the device comprising:

[0119] Memory 81, for storing computer programs;

[0120] The processor 82 is configured to implement the above-mentioned method for controlling the circuit breaker when executing a computer program.

[0121] In order to solve the above technical problems, the present application also provides a control device for a circuit breaker. For an introduction to the control device for the circuit breaker provided by the present application, please refer to the above embodiments, and the present application will not elaborate on them here.

[0122] A circuit breaker, comprising the above-mentioned circuit breaker control device, N main switch tubes corresponding one-to-one to N photovoltaic modules, and N bypass switch tubes corresponding one-to-one to N photovoltaic modules;

[0123] The positive power terminal of the processor is connected to the positive output terminal of the first photovoltaic assembly, the negative power terminal of the processor is connected to the negative output terminal of the i-th photovoltaic assembly, the first end of the first main switch tube is the positive output terminal of the circuit breaker, the second end of the i-th main switch tube is connected to the positive output terminal of the i-th photovoltaic assembly, the first end of the i+1-th main switch is connected to the negative output terminal of the i-th photovoltaic assembly, the negative output terminal of the N-th photovoltaic assembly is the negative output terminal of the circuit breaker, the first end of the bypass switch tube is connected to the first end of the corresponding main switch tube, and the second end of the bypass switch tube is connected to the negative output terminal of the corresponding photovoltaic assembly, N≥i≥1, and N and i are both integers.

[0124] In order to solve the above technical problems, the present application also provides a circuit breaker. For an introduction to the circuit breaker provided by the present application, please refer to the above embodiments, and the present application will not elaborate on them here.

[0125] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0126] It should also be noted that, in this specification, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

[0127] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Many of 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 the present invention. Therefore, the present invention is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for controlling a circuit breaker, characterized in that: A processor applied to a circuit breaker, the circuit breaker comprising N main switches corresponding one-to-one to the N photovoltaic modules and N bypass switches corresponding one-to-one to the N photovoltaic modules; The positive power terminal of the processor is connected to the positive output terminal of the first photovoltaic assembly, the negative power terminal of the processor is connected to the negative output terminal of the i-th photovoltaic assembly, the first end of the first main switch tube is the positive output terminal of the shutdown device, the second end of the i-th main switch tube is connected to the positive output terminal of the i-th photovoltaic assembly, the first end of the (i+1)th main switch tube is connected to the negative output terminal of the i-th photovoltaic assembly, the negative output terminal of the N-th photovoltaic assembly is the negative output terminal of the shutdown device, the first end of the bypass switch tube is connected to the first end of the corresponding main switch tube, and the second end of the bypass switch tube is connected to the negative output terminal of the corresponding photovoltaic assembly, N≥i≥1, and N and i are both integers; The control method includes: After receiving the heartbeat signal, controlling the N main switch tubes to be turned on; Determining whether a power supply voltage of the processor itself is less than a second undervoltage protection voltage, the second undervoltage protection voltage being less than the first undervoltage protection voltage; If the supply voltage is not less than the second undervoltage protection voltage, determining whether the supply voltage of the processor itself is less than the first undervoltage protection voltage; If the power supply voltage is lower than the first undervoltage protection voltage, the N main switches are controlled to be disconnected, and the N bypass switches are controlled to be closed; If the supply voltage is lower than the second undervoltage protection voltage, the processor is controlled to power off, and after receiving a power-on instruction, the processor is controlled to power on, and the step of determining whether the supply voltage of the processor is lower than the second undervoltage protection voltage is entered; If its own power supply voltage is not less than the first under-voltage protection voltage, the working information of the N photovoltaic components is obtained; based on the working information, it is determined whether there is a photovoltaic component with abnormal operation among the N photovoltaic components; if there is a photovoltaic component with abnormal operation, the main switch tube corresponding to the photovoltaic component with abnormal operation is controlled to be disconnected and the corresponding bypass switch tube is controlled to be turned on.

2. The method for controlling a circuit breaker according to claim 1, wherein: The bypass switch tube is a MOSFET transistor, and the MOSFET includes a body diode. After controlling the N main switch tubes to be disconnected, the method further includes: Obtaining a bypass current passing through the bypass switch tube; Determining whether the bypass current is greater than a preset current; If so, the step of controlling the N bypass switches to be closed is entered.

3. The method for controlling a circuit breaker according to claim 2, wherein: Determining whether the bypass current is greater than a preset current includes: Determining whether the bypass current is continuously greater than the preset current within a first preset time; If the bypass current is continuously greater than the preset current within the first preset time, the step of controlling the N bypass switches to be closed is entered.

4. The method for controlling a circuit breaker according to claim 1, wherein: After controlling the N main switch tubes to be turned off and controlling the N bypass switch tubes to be turned on, the method further includes: Determining whether the closing time of the N bypass switch tubes reaches a second preset time; If so, the N bypass switch tubes are controlled to be turned off, and the step of controlling the N main switch tubes to be turned on is entered.

5. The method for controlling a circuit breaker according to claim 4, wherein: Controlling the N main switch tubes to be turned on includes: Controlling the N main switching tubes to conduct at staggered peaks; Controlling the N bypass switch tubes to be disconnected includes: The order of controlling the N bypass switch tubes to be turned off is the same as the order of controlling the corresponding N main switch tubes to be turned on at staggered times.

6. A control device for a circuit breaker, characterized in that: include: memory for storing computer programs; A processor, configured to implement the method for controlling a circuit breaker according to any one of claims 1 to 5 when executing the computer program.

7. A circuit breaker, characterized in that: The circuit breaker comprises a control device according to claim 6, N main switch tubes corresponding to the N photovoltaic modules, and N bypass switch tubes corresponding to the N photovoltaic modules; The positive power terminal of the processor is connected to the positive output terminal of the first photovoltaic assembly, the negative power terminal of the processor is connected to the negative output terminal of the i-th photovoltaic assembly, the first end of the first main switch tube is the positive output terminal of the circuit breaker, the second end of the i-th main switch tube is connected to the positive output terminal of the i-th photovoltaic assembly, the first end of the i+1-th main switch is connected to the negative output terminal of the i-th photovoltaic assembly, the negative output terminal of the N-th photovoltaic assembly is the negative output terminal of the circuit breaker, the first end of the bypass switch tube is connected to the first end of the corresponding main switch tube, and the second end of the bypass switch tube is connected to the negative output terminal of the corresponding photovoltaic assembly, N≥i≥1, and N and i are both integers.

8. The circuit breaker according to claim 7, wherein: Also includes a diode, a first capacitor and a second capacitor; The anode of the diode is connected to the positive output terminal of the first photovoltaic assembly, the cathode of the diode is connected to the first end of the first capacitor and the positive power supply terminal of the processor, the second end of the first capacitor is connected to the negative output terminal of the first photovoltaic assembly and the first end of the second capacitor, and the first end of the second capacitor is connected to the power output terminal of the processor and the power supply terminal of the electrical device in the circuit breaker; The processor is further configured to convert the voltage of the positive terminal of its own power supply to supply power to the electrical equipment in the circuit breaker.

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