Photovoltaic output control circuit, method, electronic equipment and system

Abstract

The embodiment of the invention provides a photovoltaic output control circuit, a photovoltaic output control method, electronic equipment and a photovoltaic output control system. According to the circuit, a manual trigger mechanism and an automatic trigger mechanism (fault detection) are integrated in a unified hardware circuit, so that redundancy of a control path is realized, the overall reliability and flexibility of a system are improved, and reliable trigger and turn-off can be ensured in different scenes such as automatic detection failure or personnel presence. And the circuit adopts a linear OR logic design, the follow-up action can be driven when any trigger signal is effective, the parallel processing mechanism avoids the dependence of a single control path, the logic judgment process is simplified, and the response speed is improved. Besides, the whole control logic is realized by discrete components or basic integrated circuits, does not depend on complex software programs, has the advantages of low cost, strong anti-interference capability and stable work, and is particularly suitable for safety protection scenes with extremely high reliability requirements.

Description

Technical Field

[0001] This application relates to the field of photovoltaic power generation technology, and in particular to a photovoltaic output control circuit, method, electronic device and system. Background Technology

[0002] When a photovoltaic power generation system malfunctions, shutting off the DC output of the photovoltaic modules in an emergency is a key measure to ensure personal safety, prevent the spread of fire, and reduce the risk of equipment damage.

[0003] In related technologies, shutdown can be achieved through manual control. However, relying on manual operation results in poor flexibility and reliability. Summary of the Invention

[0004] This application provides a photovoltaic output control circuit, method, electronic device, and system to improve the reliability and flexibility of shutdown operation.

[0005] In a first aspect, embodiments of this application provide a photovoltaic output control circuit, including:

[0006] The first input module, with its input end connected to the fault detection module, is used to generate a first control signal in response to the fault detection module detecting a fault on the DC side of the photovoltaic power generation system.

[0007] The second input module has an input terminal connected to a manual switch and is used to generate a second control signal in response to the manual switch being turned on.

[0008] The drive module, with its input terminal connected to the first input module and the second input module, is used to generate a drive signal based on the first control signal and / or the second control signal;

[0009] The switch module has a control terminal connected to the drive module, a first terminal connected to the power supply, and a second terminal connected to the input terminal of the generator. It is used to cut off the operating power supply of the generator under the control of the drive signal, so that the generator stops sending a preset signal to the shutdown device; the preset signal is used to maintain the shutdown device on.

[0010] In one possible design, the first input module includes: a first switching transistor;

[0011] The first switching transistor is connected to the fault detection module and is used to generate a first control signal based on the fault detection signal output by the fault detection module; the fault detection signal indicates that a fault has occurred on the DC side.

[0012] In one possible design, the first input module further includes: a voltage divider unit;

[0013] The voltage divider unit has its input terminal connected to the fault detection module and is used to divide the fault detection signal to obtain a voltage divider signal.

[0014] The first switching transistor has its control terminal connected to the voltage divider unit, its first terminal connected to the power supply, and its second terminal connected to the drive module, and is used to generate a first control signal based on the voltage divider signal.

[0015] In one possible design, the first input module further includes a control unit and a wireless communication unit;

[0016] The wireless communication unit is connected to the control unit and is used to receive a remote shutdown signal sent by the terminal device.

[0017] The control unit is connected to the wireless communication unit and the fault detection module, and is used to generate a first voltage signal based on the remote shutdown signal and the fault detection signal;

[0018] The first switching transistor is connected to the control unit and is used to generate the first control signal based on the first voltage signal.

[0019] In one possible design, the second input module includes: a second switching transistor;

[0020] The second switching transistor is connected to the manual switch and is used to generate a second control signal based on the second voltage signal output when the manual switch is turned on.

[0021] In one possible design, the second input module further includes: a bias resistor;

[0022] The first end of the bias resistor is connected to one end of the manual switch, the other end of the manual switch is connected to the power supply, and the second end of the bias resistor is grounded.

[0023] The bias resistor is used to generate a second voltage signal when the manual switch is turned on;

[0024] The second switching transistor has its control terminal connected to the first terminal of the bias resistor, the first terminal connected to the power supply, and the second terminal connected to the drive module, and is used to generate a second control signal based on the second voltage signal.

[0025] In one possible design, the drive module includes: a pull-down resistor and a third switching transistor;

[0026] The pull-down resistor is connected to the first input module and the second input module, and is used to generate a third voltage signal according to the first control signal and the second control signal.

[0027] The third switch is connected to the pull-down resistor and is used to drive the third voltage signal to generate a drive signal.

[0028] In one possible design, the switching module includes a relay;

[0029] The first end of the magnetic coil of the relay is connected to the power supply, and the second end is connected to the drive module; the first end of the switch contact of the relay is connected to the power supply, and the second end is connected to the generator.

[0030] In one possible design, the first input module further includes a control unit, a first resistor, and a second resistor; the second input module includes a manual switch, a bias resistor, a third resistor, and a second switching transistor; the drive module includes a pull-down resistor, a fifth resistor, an eighth resistor, a seventh resistor, and a third switching transistor.

[0031] The input terminal of the control unit is connected to the fault detection module. The output terminal of the control unit is connected to the first terminal of the first resistor and the control terminal of the first switch through the first resistor and the first terminal of the second resistor. The second terminal of the second resistor is grounded. The first terminal of the first switch is connected to the power supply. The second terminal of the first switch is connected to the second terminal of the second switch and the first terminal of the pull-down resistor.

[0032] The first terminal of the manual switch is connected to the power supply, the second terminal of the manual switch is grounded through the bias resistor, and the second terminal of the manual switch is connected to the control terminal of the second switching transistor through the third resistor. The first terminal of the second switching transistor is connected to the power supply.

[0033] The second end of the pull-down resistor is grounded. The first end of the pull-down resistor is connected to the first end of the eighth resistor and the control terminal of the third switch through the fifth resistor. The second end of the eighth resistor is connected to the power supply. The first end of the third switch is grounded. The second end of the third switch is connected to the power supply through the seventh resistor and the second end of the third switch is connected to the control terminal of the switch module.

[0034] In a second aspect, embodiments of this application provide an electronic device, including: a photovoltaic output control circuit as described in the first aspect and various possible designs of the first aspect.

[0035] Thirdly, embodiments of this application provide a photovoltaic power generation system, including: the photovoltaic output control circuit as described in the second aspect above.

[0036] Fourthly, embodiments of this application provide a photovoltaic output control method, including:

[0037] In response to the detection of a fault on the DC side of the photovoltaic power generation system, a first control signal is generated;

[0038] A second control signal is generated in response to the manual switch being turned on;

[0039] A drive signal is generated based on the first control signal and / or the second control signal;

[0040] The power supply to the generator is cut off under the control of the drive signal, so that the generator stops sending a preset signal to the shutdown device; the preset signal is used to keep the shutdown device on.

[0041] The photovoltaic output control circuit, method, electronic device, and system provided in this embodiment integrate manual and automatic (fault detection) triggering mechanisms into a unified hardware circuit, achieving control path redundancy and improving the overall reliability and flexibility of the system. This ensures reliable shutdown triggering in different scenarios, such as automatic detection failure or personnel presence. Furthermore, the circuit employs a wire-OR logic design, where any valid trigger signal drives subsequent actions. This parallel processing mechanism avoids dependence on a single control path, simplifies the logic judgment process, and improves response speed. In addition, the entire control logic is implemented using discrete components or basic integrated circuits, without relying on complex software programs. This offers advantages such as low cost, strong anti-interference capability, and stable operation, making it particularly suitable for safety protection scenarios with extremely high reliability requirements. Attached Figure Description

[0042] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0043] Figure 1 A schematic diagram of the photovoltaic output control circuit provided in the embodiments of this application. Figure 1 ;

[0044] Figure 2 A schematic diagram of the photovoltaic output control circuit provided in the embodiments of this application. Figure 2 ;

[0045] Figure 3 This is a schematic flowchart of the photovoltaic output control method provided in the embodiments of this application.

[0046] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0048] It should be noted that the photovoltaic output control circuit, method, electronic equipment and system provided in this application can be used in the field of photovoltaic power generation technology, or in any field other than photovoltaic power generation technology. The application fields of the photovoltaic output control circuit, method, electronic equipment and system provided in this application are not limited.

[0049] This application relates to a Rapid Shutdown (RSD) device in a photovoltaic (PV) power generation system, with its core application scenario being emergency shutdown control when PV modules experience DC-side faults. During operation, if an emergency occurs on the DC side of a PV power generation system, such as a short circuit, grounding fault, or fire, the PV module array will generate high voltage (typically exceeding 600V), posing a risk of electric shock and fire. To ensure the safety of rescue personnel and protect equipment, a rapid shutdown device is needed to reduce the PV module voltage to a safe range (typically below 30V) within milliseconds.

[0050] In this scenario, the rapid shutdown device must meet the following key requirements: Safety: Quickly cut off DC power output in emergency situations; Reliability: Can trigger shutdown whether unattended or with personnel present; Flexibility: Supports multiple triggering methods (such as manual triggering or automatic system detection triggering); Compatibility: Adapts to photovoltaic systems of different sizes (such as residential and commercial).

[0051] In related technologies, the power supply to the signal generator can be cut off by manually pressing a physical switch (such as a button or knob), causing the shutdown device (receiver) to lose its control signal, thereby triggering a voltage drop in the photovoltaic module array. However, this relies on manual operation and lacks flexibility.

[0052] To address the aforementioned technical problems, the inventors of this application have discovered that manual and automatic control methods can be integrated through hardware circuitry to achieve synergy and complementarity between the two control methods. The core of this concept lies in achieving redundancy (covering both unattended and personnel-attended scenarios) and flexibility (supporting logical combinations of multiple trigger signals) in the control methods through circuit design. Based on this, an embodiment of this application provides a photovoltaic output control circuit.

[0053] The technical solutions of this application will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0054] Figure 1 A schematic diagram of the photovoltaic output control circuit provided in the embodiments of this application. Figure 1 .like Figure 1 As shown, the circuit may include:

[0055] The first input module 101 has its input terminal connected to the fault detection module and is used to generate a first control signal in response to the fault detection module detecting a fault on the DC side of the photovoltaic power generation system.

[0056] The second input module 102 has an input terminal connected to a manual switch and is used to generate a second control signal in response to the manual switch being turned on.

[0057] The drive module 103 has its input terminal connected to the first input module 101 and the second input module 102, and is used to generate drive signals according to the first control signal and / or the second control signal;

[0058] The switch module 104 has a control terminal connected to the drive module 103, a first terminal connected to the power supply, and a second terminal connected to the input terminal of the generator. It is used to cut off the operating power supply of the generator under the control of the drive signal so that the generator stops sending a preset signal to the shutdown device. The preset signal is used to keep the shutdown device on.

[0059] The photovoltaic output control circuit provided in this embodiment is based on the construction of an integrated hardware shutdown logic platform. In this circuit, the fault detection module may include, but is not limited to, sensors or protective relays used to detect DC-side insulation faults to ground, overcurrent, arcing, or abnormal temperature rises. The fault detection signal output by the module can characterize that the system is in an unsafe state.

[0060] Manual switches can refer to physical interfaces such as buttons, knobs, or toggle switches that are easy for personnel to operate on-site. A generator typically refers to the transmitting unit in a fast shutdown system that generates a carrier or digital signal of a specific frequency or encoding, while a shutdown unit refers to the receiving unit installed at the end of each photovoltaic module or group of photovoltaic modules. When it continuously receives a valid preset signal (such as an AC carrier of a certain amplitude or a specific digital command), it can keep its internal switching devices conducting, allowing the DC output of the photovoltaic module to form a circuit. Once this signal is lost, the shutdown unit can control its internal switching devices to disconnect, thereby reducing the output voltage of the photovoltaic module to a safe range.

[0061] The circuit's operation can be described as follows: During normal operation of the photovoltaic power generation system, the fault detection module can output a normal level (such as a low level), and the first input module 101 can maintain its output (first control signal) in an invalid state accordingly. Simultaneously, the manual switch is in the open state, and the second input module 102 can output an invalid second control signal. When the drive module 103 receives these two invalid signals, it can generate an invalid drive signal, keeping the switch module 104 closed, thereby providing a stable power supply to the generator. The generator can then continuously send a preset signal to the shutdown device, maintaining the conduction of the photovoltaic DC circuit.

[0062] When a fault occurs on the DC side, the fault detection module can output a transient fault detection signal (e.g., going high). The first input module 101 can respond to this change and generate a valid first control signal. Alternatively, when personnel discover an emergency, they can trigger a manual switch to turn it on. The second input module 102 can respond to this operation and generate a valid second control signal. After receiving any valid control signal from the first input module 101 and / or the second input module 102, the drive module 103 can generate a valid drive signal. This drive signal can control the switch module 104 to open, thereby cutting off the generator's operating power. After the generator loses power, it stops outputting the preset signal. When the preset signal is missing, the shutdown device can execute its internal shutdown logic, ultimately cutting off the DC power output of the photovoltaic module, achieving a rapid shutdown function.

[0063] The circuit provided in this embodiment integrates both manual and automatic (fault detection) triggering mechanisms into a unified hardware circuit, achieving control path redundancy and improving the overall reliability and flexibility of the system. This ensures reliable shutdown triggering in various scenarios, such as automatic detection failure or the presence of personnel. Furthermore, the circuit employs a wire-OR logic design, where any valid trigger signal drives subsequent actions. This parallel processing mechanism avoids dependence on a single control path, simplifies the logic judgment process, and improves response speed. In addition, the entire control logic is implemented using discrete components or basic integrated circuits, without relying on complex software programs. This results in advantages such as low cost, strong anti-interference capability, and stable operation, making it particularly suitable for safety protection scenarios with extremely high reliability requirements.

[0064] In some embodiments, the first input module may include: a first switching transistor; the first switching transistor is connected to the fault detection module and is used to generate a first control signal based on the fault detection signal output by the fault detection module; the fault detection signal indicates that a fault has occurred on the DC side.

[0065] In this embodiment, the first input module may include a first switching transistor. The first switching transistor can be a semiconductor device with controlled conduction characteristics, such as a bipolar junction transistor (BJT), a metal-oxide-semiconductor field-effect transistor (MOSFET), or an insulated-gate bipolar transistor (IGBT). The control terminal (such as the base or gate) of the first switching transistor can be directly or indirectly connected to the output terminal of the fault detection module.

[0066] The working process can be described as follows: When the fault detection module detects a DC-side fault, it outputs a fault detection signal whose level changes (e.g., from low to high). This signal can be directly applied to the control terminal of the first switching transistor, thereby controlling the conduction state of the first switching transistor between its first and second terminals. For example, when the fault detection signal is a valid high level, the first switching transistor can conduct, pulling the potential of its second terminal low (or high, depending on the specific circuit configuration). This changed potential constitutes the first control signal.

[0067] The circuit provided in this embodiment realizes direct response and level conversion of fault detection signals through a single switching transistor. The circuit structure is extremely simple, low in cost, and has a fast response speed, which can quickly convert the fault state into a logic signal that can be processed inside the circuit.

[0068] In some embodiments, the first input module may further include: a voltage divider unit; the voltage divider unit having its input terminal connected to the fault detection module, used to divide the fault detection signal to obtain a voltage divider signal; and a first switching transistor having its control terminal connected to the voltage divider unit, its first terminal connected to a power supply, and its second terminal connected to a drive module, used to generate a first control signal based on the voltage divider signal.

[0069] In this embodiment, based on the above embodiments, the first input module may further include a voltage divider unit. The voltage divider unit may include two or more resistors connected in series, with its input terminal connected to the fault detection module and its output terminal (i.e., the voltage divider point) connected to the control terminal of the first switching transistor. The function of the voltage divider unit is to divide the fault detection signal output by the fault detection module, which may have a high voltage, to obtain a voltage divider signal with a value suitable for the operation of the control terminal of the first switching transistor.

[0070] The working process can be described as follows: After the fault detection signal passes through the voltage divider unit, its voltage value is reduced to a safe and appropriate range, forming a voltage divider signal. The first switching transistor determines whether to conduct based on this voltage divider signal, thereby generating the first control signal.

[0071] The circuit provided in this embodiment improves the circuit's compatibility and safety by introducing a voltage divider unit, enabling it to adapt to fault detection modules with different output voltage levels, preventing excessive voltage from damaging the first switching transistor, and enhancing the circuit's reliability and applicability.

[0072] In some embodiments, the first input module may further include a control unit and a wireless communication unit; the wireless communication unit is connected to the control unit and is used to receive a remote shutdown signal sent by the terminal device; the control unit is connected to the wireless communication unit and the fault detection module and is used to generate a first voltage signal based on the remote shutdown signal and the fault detection signal; the first switching transistor is connected to the control unit and is used to generate a first control signal based on the first voltage signal.

[0073] In this embodiment, the first input module can adopt a more intelligent design, which may include a control unit and a wireless communication unit. The control unit can be a device with signal processing capabilities, such as a microcontroller (MCU), programmable logic device (PLD), or application-specific integrated circuit (ASIC). The wireless communication unit can be a Wi-Fi, Bluetooth, Zigbee, LoRa, or cellular mobile communication (such as 4G / 5G) module. The wireless communication unit can receive remote shutdown signals sent from remote terminal devices (such as monitoring center servers or maintenance personnel's mobile apps). The control unit can simultaneously receive remote shutdown signals from the wireless communication unit and fault detection signals from the fault detection module.

[0074] The control unit can run a preset logic program. For example, when it receives any valid remote shutdown signal or fault detection signal, its output pin can generate a valid first voltage signal (such as changing from low level to high level). The first switching transistor then changes its state according to this first voltage signal, thereby generating a first control signal.

[0075] The circuit provided in this embodiment seamlessly integrates remote control functions while retaining local automatic fault detection triggering, greatly improving the flexibility and convenience of operation. This allows maintenance personnel to implement emergency shutdown without having to be physically present at the dangerous site, making it particularly suitable for large or hard-to-access photovoltaic power plants and achieving an intelligent upgrade of the control method.

[0076] In some embodiments, the second input module may include: a second switching transistor; the second switching transistor is connected to a manual switch and is used to generate a second control signal based on a second voltage signal output when the manual switch is turned on.

[0077] In this embodiment, the second input module may include a second switching transistor. The type of the second switching transistor may be the same as or different from that of the first switching transistor. Its control terminal may be connected to the circuit node of a manual switch.

[0078] The working process can be described as follows: When the manual switch is not pressed (open), the control terminal of the second switch is at an invalid potential (e.g., low level), the second switch is cut off, and the second control signal is in an invalid state. When the manual switch is pressed (open), the circuit containing the manual switch is closed, generating a valid second voltage signal (e.g., high level) at its connection point. This second voltage signal is applied to the control terminal of the second switch, causing it to conduct, thereby generating a level transition at its second terminal, forming a valid second control signal.

[0079] The circuit provided in this embodiment reliably converts the mechanical on / off action of a manual switch into an electrical control signal through a switching transistor, achieving electrical isolation and signal adaptation between the human-machine interface and the internal logic circuit. The circuit is simple and reliable.

[0080] In some embodiments, the second input module may further include: a bias resistor; a first end of the bias resistor is connected to one end of a manual switch, the other end of the manual switch is connected to a power supply, and a second end of the bias resistor is grounded; the bias resistor is used to generate a second voltage signal when the manual switch is turned on; a second switching transistor, with its control terminal connected to the first end of the bias resistor, the first end connected to a power supply, and the second end connected to a drive module, is used to generate a second control signal based on the second voltage signal.

[0081] In this embodiment, the second input module may further include a bias resistor. This bias resistor is connected between one end of the manual switch and ground.

[0082] Its working process can be described as follows: When the manual switch is open, the bias resistor stably pulls the control terminal of the second switching transistor to ground potential (low level), ensuring that the second switching transistor is reliably turned off and preventing malfunction. When the manual switch is on, the power supply voltage is applied to the bias resistor through the manual switch, generating a high level at the first end of the bias resistor (i.e., the connection point with the manual switch), which is the second voltage signal. This high level drives the second switching transistor to turn on.

[0083] The circuit provided in this embodiment provides a clear and stable static potential (low level) for the control terminal of the second switching transistor by a bias resistor, which ensures the determinism of the circuit when the manual switch is not activated, effectively improves the anti-interference capability, avoids false triggering that may be caused by the control terminal being floating, and further enhances the reliability of the manual trigger channel.

[0084] In some embodiments, the driving module may include: a pull-down resistor and a third switching transistor; the pull-down resistor is connected to the first input module and the second input module, and is used to generate a third voltage signal according to the first control signal and the second control signal; the third switching transistor is connected to the pull-down resistor, and is used to drive the third voltage signal to generate a driving signal.

[0085] In this embodiment, the driving module may include a pull-down resistor and a third switching transistor. One end of the pull-down resistor can be connected to the output terminals of the first and second input modules (i.e., the second terminals of the first and second switching transistors), and the other end is grounded. The control terminal of the third switching transistor can be connected to the common connection point between the pull-down resistor and the output terminals of the two input modules.

[0086] The operating process can be described as follows: When there is no trigger, both the first and second switching transistors are off, and the common connection point is pulled down to ground (low level) through a pull-down resistor. This is an invalid third voltage signal, and the third switching transistor is therefore off, rendering the drive signal invalid. When the first control signal and / or the second control signal are valid (i.e., the first switching transistor and / or the second switching transistor are on), the on-state switching transistor pulls the potential of the common connection point up to the power supply voltage or other high potential, thereby generating a valid third voltage signal (high level). This high level drives the third switching transistor to turn on, thus generating a valid drive signal.

[0087] The circuit provided in this embodiment utilizes pull-down resistors and a third switching transistor to construct a simple yet efficient line-or logic gate and driver stage. The pull-down resistors ensure the stability of the default state, while the third switching transistor provides sufficient current drive capability to control the switching modules in subsequent stages. This design achieves logic aggregation and power amplification of multiple signals at extremely low cost, serving as the core logic hub of the circuit.

[0088] In some embodiments, the switching module may include a relay; a first end of the magnetic coil of the relay is connected to a power source, and a second end is connected to a drive module; a first end of the switch contact of the relay is connected to a power source, and a second end is connected to a generator.

[0089] In this embodiment, the switching module may include a relay. The relay typically includes a magnetic coil (electromagnet) and one or more sets of mechanical switch contacts controlled by the coil. One end of the relay's magnetic coil is connected to a power source, and the other end is connected to the output terminal of the drive module (i.e., the second terminal of the third switching transistor). The relay's switch contacts (normally open contacts) are connected in series in the generator's operating power supply circuit.

[0090] The working process can be described as follows: When the drive signal is invalid (the third switch is off), no current flows through the relay's magnetic coil, its switch contacts are open, and the generator is not powered. When the drive signal is valid (the third switch is on), the drive signal provides a current path to the relay coil, the coil is energized and generates magnetic force, attracting its switch contacts, thereby connecting the power supply to the generator and supplying it with power. When it is necessary to turn off, the drive signal disappears, the coil is de-energized, the contacts spring open, and the generator power supply is cut off.

[0091] The circuit provided in this embodiment uses a relay to control the switching on and off of a large current power supply with a small current drive signal, achieving good electrical isolation and power control. The complete physical disconnection of its mechanical contacts ensures thorough power cut-off and high reliability. Furthermore, as a mature and universally used component, the relay is low-cost, easy to procure and replace, and facilitates product standardization and maintenance.

[0092] The following combination Figure 2 The photovoltaic output control circuit provided in this embodiment will be described as an example.

[0093] For example, such as Figure 2 As shown, the first input module 101 may include a first switching transistor Q1. The voltage divider unit may include resistors R1 and R2, with the voltage divider node of R1 and R2 connected to the base of Q1. The collector of Q1 is connected to the power supply VCC, and the emitter is connected to the drive module 103. The first input module 101 may also include a control unit (MCU) U1. The output of U1 is connected to one end of R1, and after voltage division by R1 and R2, it is input to the base of Q1. The second input module 102 may include a bias resistor R4 and a current-limiting resistor R3. One end of R4 is connected to the power supply VCC via a manual switch K1, and the other end is grounded. One end of R3 is connected to the junction of R4 and K1, and the other end is connected to the base of the second switching transistor Q2. The collector of Q2 is connected to the power supply VCC, and the emitter is connected to the drive module 103. The drive module 103 includes a pull-down resistor R6 and a third switching transistor Q3. It may also include resistors R5, R7, and R8. One end of resistor R6 is connected to the emitters of Q1 and Q2 and to the base of Q3 via R5; the other end is grounded. One end of R8 is connected to the power supply VCC, and the other end is connected to the base of Q3. One end of R7 is connected to the power supply VCC, and the other end is connected to the emitter of Q3. The collector of Q3 is grounded. Q3 can be a PNP transistor, and Q1 and Q2 can be NPN transistors. The emitter of Q3 serves as the output terminal of the drive module 103 and is connected to the switch module 104. The switch module 104 includes a relay. One end of the relay's magnetic coil is connected to the emitter of Q3, and the other end is connected to the power supply VCC. The first terminal of the relay's switch contact is connected to the power supply VCC, and the second terminal is connected to the generator. A communication connection exists between the generator and the shutdown device.

[0094] During operation, in case of an emergency, personnel can press the manual switch K1 to close it. After K1 closes, the power supply VCC forms a path through K1 and the bias resistor R4, generating a high level at the upper end of R4. This high level is applied to the base of the second switch Q2 via the current-limiting resistor R3, driving Q2 to saturate and conduct. After Q2 conducts, its emitter potential is pulled high. Since the first switch Q1 is currently off, the potential at the common connection point of the emitters of Q1 and Q2 (i.e., the input terminal of the drive module 103) is also pulled high. This high potential acts on the base of the third switch Q3 (PNP type) through resistor R5, causing Q3 to switch from conducting to off. After Q3 turns off, its emitter output becomes low, no longer providing sufficient sustaining current to the coil of relay Y1, thus disconnecting relay Y1. The switching contacts of relay Y1 then open, cutting off the power supply to the signal generator M1. After M1 loses power, it stops sending the preset signal to maintain conduction to the shutdown device M2. When the preset signal is missing, the shutdown unit M2 executes its internal shutdown logic, thereby cutting off the DC output circuit of the photovoltaic module and achieving rapid shutdown.

[0095] When the photovoltaic inverter or other detection unit detects a fault on the DC side (such as an arc or insulation fault), the control unit U1 can output a high-level fault indication signal. This signal, after being divided by resistors R1 and R2, is applied to the base of the first switching transistor Q1, driving Q1 to saturate and conduct. After Q1 conducts, its emitter potential is pulled high. At this time, if the manual switch K1 is not activated, Q2 is in the off state. The high potential of Q1's emitter will also pull high the input potential of the drive module 103, and turn off Q3 through resistor R5. The subsequent process is exactly the same as in scenario one: the turn-off of Q3 causes relay Y1 to open, signal generator M1 to lose power, and the shutdown switch M2 to turn off due to the loss of the sustaining signal, ultimately achieving a safe shutdown of the system.

[0096] The circuit provided in this application integrates two independent and parallel hardware signal paths: manual switch triggering and automatic fault detection triggering. These are synthesized using "wired-OR" logic composed of transistors. This allows for rapid manual shutdown when no fault is detected and personnel are present, providing a direct and reliable physical interface for on-site emergency operations. Furthermore, when manual operation is inconvenient (e.g., equipment installed at height or in hazardous areas), remote or automatic shutdown can be triggered via an automatic detection module (e.g., fault signals received by the MCU), ensuring operational accessibility and safety in various practical application scenarios. Simultaneously, this circuit uses discrete components to implement the core logic, resulting in a clear structure, low cost, fast response speed, and strong anti-interference capability, providing a cost-effective and highly reliable rapid shutdown solution for photovoltaic power generation systems.

[0097] This application also provides an electronic device that may include the photovoltaic output control circuit provided in the above embodiments. This electronic device may be a key device or functional module in a photovoltaic power generation system, such as a photovoltaic inverter, photovoltaic combiner box, photovoltaic optimizer, fast shutdown signal transmitter, or independent safety shutdown controller.

[0098] The electronic device provided in this embodiment integrates a photovoltaic output control circuit, enabling the rapid shutdown triggering logic and actuator to be built into the device, thereby improving the safety integration and responsiveness of the entire photovoltaic system. Specifically, when the electronic device is part of the system, its internal fault detection module (or an external detection device interfaced with it) can monitor the system status in real time, while the manual switch provides a local emergency interface. Once the shutdown condition is met, the circuit can quickly cut off the power supply to the internal or external generator, triggering a system-level safety shutdown. This design makes safety functions no longer an add-on option but a core inherent feature of the device, helping to simplify system wiring, reduce overall costs, and ensure deep coupling between the safety mechanism and the main device's functions, resulting in more reliable operation. Simultaneously, the flexibility of supporting multiple triggering methods allows the electronic device to adapt to the diverse needs of different customers, different standards (such as NEC 690.12), and different application scenarios.

[0099] This application also provides a photovoltaic power generation system, which may include the electronic equipment provided in the above embodiments. The system may include multiple photovoltaic module arrays connected in series or parallel, a DC combiner device electrically connected to the arrays, and electronic equipment (such as an inverter, combiner box, or independent controller) containing photovoltaic output control circuitry. The generator in the electronic equipment is communicatively connected to a shutdown device located at the photovoltaic modules, forming a complete fast shutdown execution link.

[0100] The photovoltaic power generation system provided in this embodiment, by deploying electronic devices integrated with photovoltaic output control circuits, can construct a redundant, flexible, and rapidly responsive safety protection system at the system level. Specifically, the system can automatically respond to electrical faults on the DC side (such as arcing or insulation failure) through hardware circuits, or handle emergency situations through local manual triggering, and can also achieve intelligent operation and maintenance management through remote commands. When any shutdown condition is triggered, the system can cut off the generator power supply within milliseconds through unified hardware logic, causing all shutdown devices to operate synchronously due to the loss of maintenance signals, thereby reducing the output voltage of the entire photovoltaic array to a safe range. This not only greatly protects the personal safety of firefighters and maintenance personnel and reduces the risk of fire, but also meets the increasingly stringent photovoltaic safety standards and regulations. At the same time, this integrated solution avoids configuring independent and distributed peripheral circuits for different triggering methods, improves system reliability, reduces maintenance complexity and cost throughout the entire life cycle, and enables the photovoltaic power generation system to possess the key attribute of inherent safety while pursuing high-efficiency power generation.

[0101] Figure 3 This is a schematic flowchart illustrating the photovoltaic output control method provided in an embodiment of this application. Figure 3 As shown, the method may include:

[0102] 301. In response to the detection of a fault on the DC side of the photovoltaic power generation system, a first control signal is generated.

[0103] This step involves the automatic detection and response to DC-side faults in photovoltaic power generation systems.

[0104] The detection can include real-time or periodic sampling and analysis of electrical parameters on the DC side using detection devices such as current transformers, voltage sensors, insulation monitors, or arc fault circuit breakers.

[0105] Faults can be characterized as one or more unsafe conditions, such as overcurrent, short circuit, insulation resistance to ground below a threshold, detection of series or parallel arc characteristic signals, or abnormal DC bus voltage. When such a fault condition is identified, the detection device can output a fault indication signal with a state transition (e.g., transitioning from a low level to a high level, or outputting a specific digital code).

[0106] Generating the first control signal can refer to performing necessary signal conditioning (such as level conversion, isolation, and shaping) on ​​the fault indication signal to form an electrical signal that can be reliably identified by subsequent logic processing units. For example, a switching transistor circuit can be used to conduct when the fault signal is valid, thereby pulling down the potential of a connection point, and this low potential can serve as the first control signal; alternatively, an optocoupler can be used to convert the fault signal into an isolated logic level. This step transforms a physical-level system fault into a logical event that can be processed within the circuit, serving as the information source for automatic safety triggering.

[0107] 302. In response to the manual switch being turned on, a second control signal is generated.

[0108] This step involves responding to manual intervention.

[0109] Manual switches can refer to physical switching elements that are installed on the equipment panel or in an easily accessible location, such as emergency stop buttons, rotary switches, or toggle switches.

[0110] "Conduction" refers to the process by which an operator closes the contacts of a switch by pressing, rotating, or performing other actions, thus creating an electrical path.

[0111] Generating a second control signal can refer to using the electrical change caused by the conduction action to generate a control signal. Specifically, when the manual switch is turned on, a power supply voltage can be applied to a resistor network or directly to the control terminal of a switching transistor through the switch. For example, turning on the switch can connect a pull-up resistor to the power supply, thereby generating a high level at the upper end of the resistor; or, turning on the switch can directly disconnect a low-level ground path, causing a node to be pulled up to a high level. This high (or low) level change generated by manual operation constitutes the second control signal. This step reliably converts the subjective intention of the operator to shut down into a definite electrical signal through a simple mechanical and electrical action, providing the most direct emergency shutdown channel unaffected by automatic system failures.

[0112] 303. Generate a drive signal based on the first control signal and / or the second control signal.

[0113] This step involves core logical decision-making and signal-driven processes.

[0114] The triggering logic of this method is described by the first control signal and / or the second control signal, i.e., OR logic. This means that the first control signal and the second control signal are logically parallel, and the validity of either one is sufficient to trigger subsequent actions. There is no interlocking or priority arbitration between the two (unless specifically designed in a particular extended embodiment).

[0115] Generating the drive signal can refer to the logical synthesis and power amplification of the aforementioned control signals. In a typical implementation, the first and second control signals can control the conduction of two switching transistors, whose outputs can be connected together and grounded (or connected to the power supply) through a common pull-down (or pull-up) resistor. When either switching transistor is turned on, the potential at the common connection point will change, and this changed potential signal constitutes a third voltage signal. Subsequently, this third voltage signal can be applied to the gate of a third switching transistor (such as a MOSFET) to control its conduction or cutoff. The large current output or level switching generated when the third switching transistor is turned on forms the final drive signal. This step realizes signal aggregation through hardware lines or logic, and completes logical judgment and drive capability enhancement with a simple circuit, preparing the conditions for executing the final power operation.

[0116] 304. Under the control of the drive signal, the power supply of the generator is cut off so that the generator stops sending the preset signal to the shutdown device; the preset signal is used to keep the shutdown device on.

[0117] This step involves the final execution, the physical action that performs the safe shutdown.

[0118] The phrase "under the control of the drive signal" indicates that the drive signal is the direct enabling condition for performing the action.

[0119] Disconnecting the power supply to the generator can refer to controlling a switching device connected in series in the generator's power supply circuit to disconnect. Specifically, a drive signal can control the coil of a relay or contactor. When the drive signal is valid (e.g., providing drive current), the coil pulls its normally closed contact open (or releases its normally open contact), thus physically disconnecting the power supply line. Alternatively, the drive signal can directly control the gate of a power MOSFET or IGBT, turning it off, thereby achieving solid-state switching power disconnection.

[0120] The generator typically refers to the signal transmitting unit in a fast shutdown system. It requires a power supply to generate and transmit a specific preset signal (e.g., a high-frequency carrier signal of a certain frequency or a digital signal modulated with a specific code). This preset signal is transmitted via power line carrier or a dedicated communication cable to the shutdown device installed next to each photovoltaic module. The preset signal is used to maintain the shutdown device's conduction, describing its function: as long as the shutdown device continuously receives a valid preset signal, its internal electronic switches (such as MOSFETs connected back-to-back) remain on, allowing the DC current of the photovoltaic module to flow normally. Once step 304 is executed, the generator loses power and stops transmitting signals. All shutdown devices will immediately control their internal switches to open due to signal loss, thereby reducing the output voltage of the photovoltaic string to a safe range close to zero volts. This step completes the final closed loop from logic instruction to safe state transition.

[0121] The photovoltaic output control method provided in this application, through parallel response to automatic fault detection and manual triggering, and by employing OR logic to synthesize drive signals, can construct a redundant and reliable shutdown triggering mechanism, ensuring that shutdown can be executed whenever any triggering path is valid. By executing explicit steps based on hardware state, millisecond-level fast response can be achieved, meeting safety standard requirements. Through modular functional definition, it can flexibly adapt to different detection technologies and actuators, improving the versatility and portability of the solution. Finally, by cutting off the generator power supply to stop it from sending sustaining signals, the photovoltaic module-side shutdown device can be reliably triggered, thereby reducing the array output voltage to a safe range and effectively ensuring personal and equipment safety.

[0122] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the execution may include the steps of the above-described method embodiments; and the aforementioned storage medium may include various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0123] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and may include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A photovoltaic output control circuit, characterized in that, include: The first input module, with its input end connected to the fault detection module, is used to generate a first control signal in response to the fault detection module detecting a fault on the DC side of the photovoltaic power generation system. The second input module has an input terminal connected to a manual switch and is used to generate a second control signal in response to the manual switch being turned on. The drive module, with its input terminal connected to the first input module and the second input module, is used to generate a drive signal based on the first control signal and / or the second control signal; A switch module, with its control terminal connected to the drive module, a first terminal connected to a power supply, and a second terminal connected to the input terminal of a generator, is used to cut off the operating power supply of the generator under the control of the drive signal, so that the generator stops sending a preset signal to the shutdown device. The preset signal is used to keep the switch on; The first input module includes: a first switching transistor; The first switching transistor is connected to the fault detection module and is used to generate a first control signal based on the fault detection signal output by the fault detection module; the fault detection signal indicates that a fault has occurred on the DC side.

2. The circuit according to claim 1, characterized in that, The first input module further includes: a voltage divider unit; The voltage divider unit has its input terminal connected to the fault detection module and is used to divide the fault detection signal to obtain a voltage divider signal. The first switching transistor has its control terminal connected to the voltage divider unit, its first terminal connected to the power supply, and its second terminal connected to the drive module, and is used to generate a first control signal based on the voltage divider signal.

3. The circuit according to claim 1, characterized in that, The first input module also includes a control unit and a wireless communication unit; The wireless communication unit is connected to the control unit and is used to receive a remote shutdown signal sent by the terminal device. The control unit is connected to the wireless communication unit and the fault detection module, and is used to generate a first voltage signal based on the remote shutdown signal and the fault detection signal; The first switching transistor is connected to the control unit and is used to generate the first control signal based on the first voltage signal.

4. The circuit according to claim 1, characterized in that, The second input module includes: a second switching transistor; The second switching transistor is connected to the manual switch and is used to generate a second control signal based on the second voltage signal output when the manual switch is turned on.

5. The circuit according to claim 4, characterized in that, The second input module further includes: a bias resistor; The first end of the bias resistor is connected to one end of the manual switch, the other end of the manual switch is connected to the power supply, and the second end of the bias resistor is grounded. The bias resistor is used to generate a second voltage signal when the manual switch is turned on; The control terminal of the second switching transistor is connected to the first terminal of the bias resistor, the first terminal of the second switching transistor is connected to the power supply, and the second terminal of the second switching transistor is connected to the drive module, for generating a second control signal based on the second voltage signal.

6. The circuit according to any one of claims 1-5, characterized in that, The driving module includes: a pull-down resistor and a third switching transistor; The pull-down resistor is connected to the first input module and the second input module, and is used to generate a third voltage signal according to the first control signal and / or the second control signal; The third switch is connected to the pull-down resistor and is used to drive the third voltage signal to generate a drive signal.

7. The circuit according to any one of claims 1-5, characterized in that, The switching module includes a relay; The first end of the magnetic coil of the relay is connected to the power supply, and the second end of the relay is connected to the drive module; the first end of the switch contact of the relay is connected to the power supply, and the second end of the relay is connected to the generator.

8. The circuit according to claim 1, characterized in that, The first input module further includes a control unit, a first resistor, and a second resistor; the second input module includes a manual switch, a bias resistor, a third resistor, and a second switching transistor; the drive module includes a pull-down resistor, a fifth resistor, an eighth resistor, a seventh resistor, and a third switching transistor. The input terminal of the control unit is connected to the fault detection module. The output terminal of the control unit is connected to the first terminal of the first resistor and the control terminal of the first switch through the first resistor and the first terminal of the second resistor. The second terminal of the second resistor is grounded. The first terminal of the first switch is connected to the power supply. The second terminal of the first switch is connected to the second terminal of the second switch and the first terminal of the pull-down resistor. The first terminal of the manual switch is connected to the power supply, the second terminal of the manual switch is grounded through the bias resistor, and the second terminal of the manual switch is connected to the control terminal of the second switching transistor through the third resistor. The first terminal of the second switching transistor is connected to the power supply. The second end of the pull-down resistor is grounded. The first end of the pull-down resistor is connected to the first end of the eighth resistor and the control terminal of the third switch through the fifth resistor. The second end of the eighth resistor is connected to the power supply. The first end of the third switch is grounded. The second end of the third switch is connected to the power supply through the seventh resistor and the second end of the third switch is connected to the control terminal of the switch module.

9. An electronic device, characterized in that, Includes the photovoltaic output control circuit as described in any one of claims 1-8.

10. A photovoltaic power generation system, characterized in that, Including the electronic device as described in claim 9.

11. A photovoltaic output control method, characterized in that, The method, applied to the photovoltaic output control circuit as described in any one of claims 1-8, comprises: In response to the detection of a fault on the DC side of the photovoltaic power generation system, a first control signal is generated; A second control signal is generated in response to the manual switch being turned on; A drive signal is generated based on the first control signal and / or the second control signal; The power supply to the generator is cut off under the control of the drive signal, so that the generator stops sending a preset signal to the shutdown device; the preset signal is used to keep the shutdown device on.

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