Switch control circuit, inverter and photovoltaic power generation system

Abstract

The present application discloses a switch control circuit, an inverter and a photovoltaic power generation system, which belong to the field of electric power technology. The switch control circuit includes: an energy storage module and a self-locking module; the energy storage module is used to store electric energy based on the power supply of the target power supply and supply power to the self-locking module based on the stored electric energy; the self-locking module is used to latch the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to disconnect, so that the releaser completes the tripping action. The switch control circuit, inverter and photovoltaic power generation system disclosed in the present application store electric energy and supply power to the self-locking module based on the power supply of the target power supply through the energy storage module, latch the input tripping control signal through the self-locking module to control the target switch to disconnect, so that the releaser completes the tripping action, and under the joint action of the energy storage module and the self-locking module, the risk of not being able to stably and reliably trip can be at least reduced or even completely solved, and the reliability of switch control can be improved.

Description

Technical Field

[0001] The present application belongs to the field of electric power technology, and in particular relates to a switch control circuit, an inverter and a photovoltaic power generation system. Background Art

[0002] Photovoltaic power generation systems can achieve high efficiency and energy conservation, and solve problems such as energy shortages and environmental pollution. In photovoltaic power generation systems, inverters are used to convert the DC power output by photovoltaic modules into AC power and transmit it directly to the power grid. In the actual operation of the inverter, if the inverter fails, the inverter is still powered on and continues to work, which will directly or indirectly cause more serious or even irreversible damage to the inverter itself, and may also cause damage to other devices connected to the inverter (such as other inverters in parallel, energy storage devices or household appliances, etc.).

[0003] In order to avoid the above phenomenon, a DC switch is generally set on the DC input side of the inverter. In the event of a fault in the inverter, the DC switch is disconnected, disconnecting the connection between the inverter and the photovoltaic module, thereby preventing the inverter from continuing to work in a faulty state. At present, the inverter is also provided with a tripper that cooperates with the DC switch. In the event of a fault in the inverter, a tripping control signal is sent to the target switch used to control the tripper to perform a tripping action, thereby performing a tripping action through the tripper, so that the DC switch is disconnected. However, the existing inverter has the problem of being unable to complete the tripping action when the tripping control signal is unstable, which in turn causes the DC switch to be unable to disconnect, that is, the existing technology has the problem of poor reliability in controlling the tripper to perform a tripping action. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a switch control circuit, an inverter and a photovoltaic power generation system, which can improve the reliability of control.

[0005] In a first aspect, the present application provides a switch control circuit, the switch control circuit comprising: an energy storage module and a self-locking module;

[0006] The energy storage module is used to store electric energy based on the power supply of the target power supply and to supply power to the self-locking module based on the stored electric energy;

[0007] The self-locking module is used to latch the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected so that the releaser completes the tripping action.

[0008] According to the switch control circuit of the present application, the energy storage module stores electric energy based on the power supply of the target power supply and supplies power to the self-locking module based on the stored electric energy. The self-locking module latches the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected, so that the releaser completes the tripping action. Under the joint action of the energy storage module and the self-locking module, it can be achieved that when the power supply module or the sampling control module is abnormal and can only send a single tripping control signal, the signal obtained by latching the single tripping control signal is still sufficient to drive the target switch to be disconnected, so that the releaser completes the tripping action. The risk of not being able to stably and reliably trip when the power supply module or the sampling control module is abnormal can be at least reduced or even completely solved, the reliability of the switch control can be improved, the possibility of the spread of faults such as short circuit or DC arc of photovoltaic components can be reduced, and the safety and reliability of the inverter and photovoltaic power generation system can be improved.

[0009] According to an embodiment of the present application, the self-locking module is specifically used to extend the effective level duration of the trip control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected.

[0010] According to an embodiment of the present application, the self-locking module is further used to filter out pulses whose duration is less than a preset duration.

[0011] According to the switch control circuit of the present application, the self-locking module filters out pulses with a duration less than a preset duration, thereby filtering out interference signals generated by the extremely large current change rate (di / dt) and voltage change rate (dv / dt) generated by the rapid action of the power switch tube in the power module of the inverter, avoiding false operation of the release, avoiding false tripping that causes the DC switch to disconnect, and improving the reliability of the release operation.

[0012] According to one embodiment of the present application, the self-locking module includes a filtering unit and a self-locking unit;

[0013] The input signal of the self-locking module is processed by the filtering unit and then input into the self-locking unit;

[0014] The filtering unit is used to filter out pulses with a duration shorter than a preset duration;

[0015] The self-locking unit is used to extend the effective level duration of the trip control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected.

[0016] According to an embodiment of the present application, the self-locking module includes: a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor, a second capacitor, a first switch tube and a second switch tube;

[0017] The first end of the first resistor is connected to the input end of the self-locking module; the second end of the first resistor is connected to the first end of the second resistor and the second end of the second switch tube;

[0018] The second end of the second resistor is connected to the first end of the first switch tube and the first end of the first capacitor;

[0019] The third end of the first switch tube and the second end of the first capacitor are grounded;

[0020] The second end of the first switch tube is connected to the first end of the fourth resistor;

[0021] The second end of the fourth resistor is connected to the first end of the second switch tube, the first end of the second capacitor, and the first end of the fifth resistor;

[0022] The first end of the third resistor is connected to the third end of the second switch tube and the second end of the second capacitor;

[0023] The second end of the third resistor and the second end of the fifth resistor are connected to a power supply.

[0024] According to one embodiment of the present application, the energy storage module includes an energy storage unit and a switch unit for connecting the energy storage unit to the target power source;

[0025] The energy storage unit is used to store electric energy based on the power supply of the target power supply and to supply power to the self-locking module based on the stored electric energy;

[0026] When there is an abnormality in the power supply from the target power source to the energy storage module, the switch unit disconnects the energy storage unit from the target power source.

[0027] According to one embodiment of the present application, the energy storage unit includes a voltage-type energy storage element;

[0028] The switch unit includes a first switch subunit and a second switch subunit; the first switch subunit and the second switch subunit are connected in parallel; the first switch subunit and the second switch subunit are both used to connect the target power supply and the energy storage unit;

[0029] When the target power supply to the energy storage module is normal and the voltage of the energy storage unit is lower than a first threshold, the first switch subunit is turned on; when the target power supply to the energy storage module is normal and the voltage of the energy storage unit is higher than a second threshold, the first switch subunit is turned off; when there is an abnormality in the power supply to the energy storage module by the target power supply, the second switch subunit is turned off after the first switch subunit is turned off; the second threshold is greater than the first threshold.

[0030] According to one embodiment of the present application, the first switch subunit includes a fully controllable device.

[0031] According to one embodiment of the present application, the fully-controlled device includes at least one of an IGBT, a MOSFET, a triode and a relay.

[0032] According to an embodiment of the present application, the switch unit includes a diode.

[0033] In a second aspect, the present application provides an inverter, the inverter comprising: a target switch, a DC switch, a tripper, and a switch control circuit as described in the first aspect;

[0034] The switch control circuit is used to control the target switch;

[0035] When the target switch is disconnected, the releaser completes the tripping action to disconnect the DC switch.

[0036] According to the inverter of the present application, the energy storage module stores electric energy based on the power supply of the target power supply and supplies power to the self-locking module based on the stored electric energy. The self-locking module latches the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected, so that the releaser completes the tripping action. Under the joint action of the energy storage module and the self-locking module, it can be achieved that when the power supply module or the sampling control module is abnormal and can only send a single tripping control signal, the signal obtained by latching the single tripping control signal is still sufficient to drive the target switch to be disconnected, so that the releaser completes the tripping action. The risk of not being able to stably and reliably trip when the power supply module or the sampling control module is abnormal can be at least reduced or even completely solved, the reliability of switch control can be improved, the possibility of the spread of faults such as short circuit or DC arc of photovoltaic components can be reduced, and the safety and reliability of the inverter and photovoltaic power generation system can be improved.

[0037] In a third aspect, the present application provides a photovoltaic power generation system, the inverter comprising: a photovoltaic component and the inverter described in the second aspect.

[0038] According to the photovoltaic power generation system of the present application, the energy storage module stores electric energy based on the power supply of the target power source and supplies power to the self-locking module based on the stored electric energy. The self-locking module latches the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected, so that the releaser completes the tripping action. Under the joint action of the energy storage module and the self-locking module, it can be achieved that when the power supply module or the sampling control module is abnormal and can only send a single tripping control signal, the signal obtained by latching the single tripping control signal is still sufficient to drive the target switch to be disconnected, so that the releaser completes the tripping action. The risk of not being able to stably and reliably trip when the power supply module or the sampling control module is abnormal can be at least reduced or even completely solved, the reliability of switch control can be improved, the possibility of the spread of faults such as short circuit or DC arc of photovoltaic components can be reduced, and the safety and reliability of the inverter and photovoltaic power generation system can be improved.

[0039] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0041] Figure 1 It is a structural schematic diagram of a photovoltaic power generation system in the prior art;

[0042] Figure 2 is a schematic diagram of the structure of a switch control circuit provided in an embodiment of the present application;

[0043] Figure 3 This is one of the structural schematic diagrams of the photovoltaic power generation system provided in the embodiment of the present application;

[0044] Figure 4 This is one of the working timing diagrams of the self-locking module in the switch control circuit provided in the embodiment of the present application;

[0045] Figure 5 This is the second working timing diagram of the self-locking module in the switch control circuit provided in the embodiment of the present application;

[0046] Figure 6 This is the second structural schematic diagram of the photovoltaic power generation system provided in the embodiment of the present application;

[0047] Figure 7 is a schematic structural diagram of a filter unit in a switch control circuit provided in an embodiment of the present application;

[0048] Figure 8 This is the third working timing diagram of the self-locking module in the switch control circuit provided in the embodiment of the present application;

[0049] Fig. 9 This is the fourth working timing diagram of the self-locking module in the switch control circuit provided in the embodiment of the present application;

[0050] Fig.10 This is the fifth working timing diagram of the self-locking module in the switch control circuit provided in the embodiment of the present application;

[0051] Fig.11 This is the sixth working timing diagram of the self-locking module in the switch control circuit provided in the embodiment of the present application;

[0052] Fig.12 This is the third structural schematic diagram of the photovoltaic power generation system provided in the embodiment of the present application;

[0053] Fig.13 This is the fourth structural schematic diagram of the photovoltaic power generation system provided in the embodiment of the present application;

[0054] Fig.14 This is the fifth structural schematic diagram of the photovoltaic power generation system provided in the embodiment of the present application;

[0055] Fig.15 This is the sixth structural schematic diagram of the photovoltaic power generation system provided in the embodiment of the present application;

[0056] Fig.16 This is the seventh structural schematic diagram of the photovoltaic power generation system provided in the embodiment of the present application. DETAILED DESCRIPTION

[0057] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0058] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0059] In the related art, during the actual operation of the inverter, at least one of the following reasons, such as a short circuit of the photovoltaic module, reverse connection of the photovoltaic module, and a DC arc fault caused by poor contact or insulation damage of the DC side wires, can cause the inverter to fail.

[0060] like Figure 1 As shown, a DC switch and a trip device matched with the DC switch can be provided on the DC input side (also called the DC power supply side) of the inverter in the related art. The on and off of the DC switch can be controlled by the matched trip device. In the case of a fault in the inverter, the DC switch can be manually disconnected, or, in the case that the sampling control module of the inverter detects that the inverter has a fault, a trip control signal can be issued to control the target switch S1 to be closed, so that the trip device performs a tripping action, thereby disconnecting the DC switch.

[0061] The inverter may also include a power supply module for supplying power to other modules (such as a trip unit and a sampling control module, etc.), and a power module for converting the direct current generated by the photovoltaic module into alternating current and outputting it. The photovoltaic module can generate direct current based on the photovoltaic effect.

[0062] In the event of an abnormality in the power supply module, sufficient power cannot be provided to the release, and the electromagnet in the release cannot be driven correctly, resulting in the release being unable to complete the tripping action, and there is a risk that the release may not trip normally.

[0063] In the event of an abnormality in the sampling control module (such as abnormal power failure of the sampling control module, etc.), the duration of the effective level in the trip control signal output by the sampling control module is short and the stability is poor, which cannot ensure that the electromagnet in the releaser is reliably attracted, and cannot ensure that the releaser completes the tripping action. There is a risk that the releaser cannot trip reliably.

[0064] The rapid action of the power switch tubes (such as IGBT, MOSFET, diode and other components) in the power module of the inverter can produce extremely large current change rates (di / dt) and voltage change rates (dv / dt). The above extremely large current change rates and voltage change rates can generate interference signals that interfere with the trip control signal to a certain extent through PCB (Printed Circuit Board, printed circuit board, circuit board or circuit board) or spatial magnetic field coupling. In severe cases, the above interference signals may even cause the trip device to malfunction (i.e., erroneously perform the tripping action). In the actual operation of the inverter, the reliability requirements of the trip device are very high. When the inverter is operating normally, the trip device malfunctions due to the interference signal and shuts off the above DC switch, which will affect the power generation efficiency and customer experience of the photovoltaic power generation system.

[0065] In summary, the reliability of controlling the releaser to perform the tripping action by controlling the target switch S1 to close in the related art is poor.

[0066] The switch control circuit, inverter and photovoltaic power generation system provided in the embodiments of the present application are described in detail below through specific embodiments and their application scenarios in conjunction with the accompanying drawings.

[0067] like Figure 2 As shown, a switch control circuit includes: an energy storage module 210 and a self-locking module 220.

[0068] In actual implementation, Figure 3 As shown, the switch control circuit can be applied to a photovoltaic power generation system. The switch control circuit can be specifically applied to an inverter 310 in a photovoltaic power generation system, and is used to control a target switch S1 in the inverter 310. When the target switch S1 is closed, the tripper 311 in the inverter 310 can perform a tripping action, and the power supply coil of the tripper 311 is normally excited to generate a magnetic field, and the DC switch 312 provided on the DC input side of the inverter 310 is disconnected, so that the connection between the inverter 310 and the photovoltaic module 320 is disconnected. The DC switch 312 is used to connect the inverter 310 and the photovoltaic module 320.

[0069] It should be noted that the inverter 310 may also include a power supply module 313, a power module 314 and a sampling control module 315. The power supply module 313, the power module 314 and the sampling control module 315 may respectively have the same functions as the power supply module, the power module and the sampling control module in a traditional inverter.

[0070] In actual implementation, an energy storage module 210 and a self-locking module 220 may be added to the rear stage of the power supply module of the traditional inverter. The tripping control signal output by the sampling control module 315 is not directly input to the target switch S1, but is processed by the self-locking module 220 before being input to the target switch S1.

[0071] The energy storage module 210 is used to store electric energy based on the power supply of the target power source and to supply power to the self-locking module 220 based on the stored electric energy.

[0072] In actual implementation, the energy storage module 210 can store electric energy based on the power supply of the target power source. The energy storage module 210 can supply power to the self-locking module 220 based on the electric energy stored in itself.

[0073] In some embodiments, the electric energy stored in the energy storage module 210 can also supply power to the target switch S1 and the release 311. That is, compared with the way in which the power supply module 313 in the traditional inverter directly supplies power to the target switch S1 and the release, in the embodiment of the present application, the target switch S1 and the release 311 can be powered by the energy storage module 210 based on the electric energy stored in the energy storage module 210.

[0074] When the energy storage module 210 still supplies power to the target switch S1 and the release 311, even if the power supply module 313 or the related branch fails and cannot work normally, and cannot supply power to the target switch S1 and the release 311, the tripping control signal issued by the sampling control module 315 can still drive the release 311 to perform a tripping action, so that the DC switch 312 is disconnected.

[0075] In some embodiments, the target power source may be the power supply module 313 , or may be other external power sources relative to the switch control circuit.

[0076] The self-locking module 220 is used to latch the input tripping control signal based on the electric energy provided by the energy storage module 210 to control the target switch S1 to be disconnected, so that the tripper 311 completes the tripping action.

[0077] In actual implementation, the function of the self-locking module 220 is to perform latching processing on the tripping control signal output by the sampling control module 315, so that even if the duration of the effective level in the tripping control signal output by the sampling control module 315 is short and the stability is poor, after the self-locking module 220 performs latching processing, the target switch S1 can still be stably controlled to close, so that the tripper 311 can perform normally and complete the tripping action, so that the DC switch 312 can be disconnected. Generally, the tripping control signal is generally a high-level signal that lasts for a certain period of time.

[0078] In some embodiments, the self-locking module 220 may include any existing self-locking circuit.

[0079] It can be understood that, when the target switch S1 is disconnected, the circuit controlling the release 311 is disconnected, so that the normally closed contact of the release 311 can remain in a closed state. When the target switch S1 is closed, the circuit controlling the release 311 is closed, so that the release 311 is controlled to perform a tripping action, so that the normally closed contact of the release 311 is disconnected. If the normally closed contact of the release 311 is successfully disconnected, the release 311 completes the tripping action. When the release 311 completes the tripping action, the DC switch 312 can be disconnected.

[0080] It should be noted that, when the sampling control module 315 loses power and cannot work due to a failure of the power supply module 313 or a failure of the sampling control module 315, the sampling control module 315 can send a single tripping control signal while relying on the residual power of the internal capacitor to maintain operation for a short period of time. Due to the existence of the self-locking module 220, the single tripping control signal sent by the sampling control module 315 before power failure can still drive the release 311 to complete the tripping action, so that the DC switch 312 is disconnected.

[0081] According to the switch control circuit provided in the embodiment of the present application, the energy storage module stores electric energy based on the power supply of the target power supply and supplies power to the self-locking module based on the stored electric energy. The self-locking module latches the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected, so that the releaser completes the tripping action. Under the joint action of the energy storage module and the self-locking module, it can be achieved that when the power supply module or the sampling control module is abnormal and can only send a single tripping control signal, the signal obtained by latching the single tripping control signal is still sufficient to drive the target switch to be disconnected, so that the releaser completes the tripping action. The risk of not being able to stably and reliably trip when the power supply module or the sampling control module is abnormal can be at least reduced or even completely solved, the reliability of the switch control can be improved, the possibility of the spread of faults such as short circuit or DC arc of photovoltaic components can be reduced, and the safety and reliability of the inverter and photovoltaic power generation system can be improved.

[0082] In some embodiments, the self-locking module 220 is specifically configured to extend the effective level duration of the trip control signal based on the electric energy provided by the energy storage module 210 to control the target switch S1 to be disconnected.

[0083] In actual implementation, the self-locking module 220 performs latching processing on the tripping control signal, which may include: extending the effective level duration of the tripping control signal to be sufficient to stably control the target switch S1 to be closed.

[0084] Figure 4 and Figure 5 The following are two timing diagrams of the self-locking module 220. When the target switch S1 is high level effective, the timing diagram of the self-locking module 220 is as follows: Figure 4 When the target switch S1 is low level and effective, the timing of the self-locking module 220 is as follows: Figure 5 shown.

[0085] High level valid means that when the control signal input to the target switch S1 is at a high level, the target switch S1 is switched to its open or closed state. Low level valid means that when the control signal input to the target switch S1 is at a low level, the target switch S1 is switched to its open or closed state. In the embodiment of the present application, in the scenario where the target switch S1 is controlled to trigger the release 311 to perform a tripping action, the target switch S1 is switched from an open state to a closed state.

[0086] like Figure 4 As shown, y 1 is the input signal of the self-locking module 220, y 2 is the output signal after the self-locking module 220 processes the input signal. The sampling control module 315 t 1, a trip control signal is sent out and input to the self-locking module 220, and the self-locking module 220 then outputs a corresponding high-level signal; the electric energy of the sampling control module 315 is t 2 Moment is exhausted, the trip control signal cannot maintain a high level, y 1 is restored to a low level, but through the processing of the self-locking module 220, under the action of the self-locking module 220, y 2 can still maintain a high level; t At time 3, the electric energy stored in the energy storage module 210 is consumed. y 2 eventually returns to a low level signal.

[0087] It can be understood that even if the effective level of the trip control signal is maintained for only T 1, but under the action of the self-locking module 220, the duration of the effective level in the trip control signal can be extended to T 2. Among them, T 2 can be determined by the electric energy stored in the energy storage module 210. If the energy storage module 210 can continuously supply power to the self-locking module 220, then y 2 can always maintain a high level. In the case where the sampling control signal is not processed by the self-locking module 220 and directly drives the target switch S1, if the effective level of the sampling control signal is maintained for only T 1, T 1 is less than the minimum pulse width time of the tripper 311, the tripper 311 is at great risk and cannot stably complete the tripping action. The effective level duration of the sampling control signal is extended by the self-locking module 220 (by T 1Extended to T 2, T 1< T 2, T 2 is greater than the minimum pulse width time of the release 311), the output signal of the self-locking module 220 y2 driving the target switch S1, it can ensure the effective level for driving the target switch S1 ( Figure 4 The duration of the high level in the middle ensures that the releaser 311 can stably complete the tripping action.

[0088] Similarly, if Figure 5 As shown, y 1 is the input signal of the self-locking module 220, y 2 is the output signal after the self-locking module 220 processes the input signal. The sampling control module 315 t 1, a trip control signal is sent out and input to the self-locking module 220, and the self-locking module 220 then outputs a corresponding low-level signal; the electric energy of the sampling control module 315 is t 2 Moment is exhausted, the trip control signal cannot maintain a high level, y 1 is restored to a low level, but through the processing of the self-locking module 220, under the action of the self-locking module 220, y 2 can still maintain a low level; t At time 3, the electric energy stored in the energy storage module 210 is consumed. y 2 is finally restored to a low level signal. The effective level duration of the sampling control signal is extended by the self-locking module 220 (by T 1Extended to T 2, T 1< T 2, T 2 is greater than the minimum pulse width time of the release 311), the output signal of the self-locking module 220 y 2 driving the target switch S1, it can ensure the effective level for driving the target switch S1 ( Figure 5 The duration of the tripping time (in which the level is low) ensures that the tripping device 311 can stably complete the tripping action.

[0089] The energy storage module supplies power based on the target power supply, stores electric energy and supplies power to the self-locking module based on the stored electric energy, latches the input tripping control signal based on the electric energy provided by the energy storage module through the self-locking module, and converts it into a continuous and stable driving signal to control the target switch to disconnect, so that the releaser completes the tripping action. Under the joint action of the energy storage module and the self-locking module, it can be achieved that when the power supply module or the sampling control module is abnormal and can only send a single tripping control signal, the signal obtained by latching the single tripping control signal is still sufficient to drive the target switch to disconnect, so that the releaser completes the tripping action, which can at least reduce or even completely solve the risk of not being able to stably and reliably trip when the power supply module or the sampling control module is abnormal, can improve the reliability of switch control, can reduce the possibility of the spread of faults such as short circuit or DC arc of photovoltaic components, and can improve the safety and reliability of inverters and photovoltaic power generation systems.

[0090] In some embodiments, the self-locking module 220 is further used to filter out pulses whose duration is less than a preset duration.

[0091] In actual implementation, the self-locking module 220 may also filter out pulses whose duration is less than a preset duration.

[0092] In some embodiments, the preset time length may be less than the minimum pulse width time of the trip unit 311. The preset time length The specific value of the preset time length is not limited in the embodiment of the present application.

[0093] According to the switch control circuit provided in the embodiment of the present application, the pulses with a duration less than a preset duration are filtered out by the self-locking module, so that interference signals generated by the extremely large current change rate (di / dt) and voltage change rate (dv / dt) generated by the rapid action of the power switch tube in the power module of the inverter can be filtered out, thereby avoiding malfunction of the release and avoiding disconnection of the DC switch due to malfunction, thereby improving the reliability of the operation of the release.

[0094] In some embodiments, Figure 6 As shown, the self-locking module 220 may include a filtering unit 610 and a self-locking unit 620 ; the input signal of the self-locking module 220 is processed by the filtering unit 610 and then input into the self-locking unit 620 .

[0095] In some embodiments, the self-locking module 220 may include a filtering unit 610 and a self-locking unit 620. The input signal of the self-locking module 220 may be first filtered by the filtering unit 610 and then input to the self-locking unit 620 for processing to obtain the output signal of the self-locking module 220.

[0096] The filtering unit 610 is used to filter out pulses with a duration shorter than a preset duration.

[0097] In actual implementation, the filtering unit 610 of the self-locking module 220 can be specifically used to filter out pulses whose duration is less than a preset duration.

[0098] In some embodiments, the filter unit 610 may be a low-pass filter that allows low-frequency signals to pass through and blocks high-frequency signals from passing through.

[0099] In some embodiments, the filter unit 610 may be Figure 7 The first-order RC passive low-pass filter shown below Figure 7 Taking the filter unit 610 as an example, the principle that the filter unit 610 can effectively filter out interference signals is explained.

[0100] The input signal of the self-locking module 220 is , Including duration The pulse amplitude is ,but It can be expressed as:

[0101] (1).

[0102] The input signal of the filter unit 610 is also , the output signal of the filter unit 610 is The current in the loop of the filter unit 610 i (t), the voltage across the capacitor in the filter unit 610 and the current flowing through the capacitor have the following relationship:

[0103] (2).

[0104] Wherein, C represents the capacitance value of the capacitor in the filter unit 610 .

[0105] According to Kirchhoff's equation, the following relationship can be obtained:

[0106] (3).

[0107] Combining the above formulas (1) to (3), we can get the output signal The expression is:

[0108] (4).

[0109] Here, R represents the resistance value of the resistor in the filter unit 610 .

[0110] The high level threshold of the input of the self-locking unit 620 is u e , the RC parameters of the first-order RC passive low-pass filter need to satisfy the following relationship:

[0111] (5).

[0112] Simplifying formula (5), we can get

[0113] (6).

[0114] because is less than the preset duration, so It is also smaller than the minimum pulse width time of the tripper 311, so that the filter unit 610 can be reasonably designed in advance, and suitable capacitors and resistors can be selected to form a first-order RC passive low-pass filter to effectively filter out interference signals.

[0115] It can be understood that the interference signal generated by the extremely large current change rate (di / dt) and voltage change rate (dv / dt) generated by the rapid action of the power switch tube in the power module of the inverter is generally a high-frequency pulse with a very short duration (less than or much less than the minimum pulse width time for the release 311 to work). Therefore, by filtering out pulses with a duration less than the preset duration through the filtering unit 610, the influence of the above-mentioned interference signal can be effectively eliminated to prevent false tripping.

[0116] The self-locking unit 620 is used to extend the effective level duration of the trip control signal based on the electric energy provided by the energy storage module 210, so as to control the target switch S1 to be disconnected.

[0117] In actual implementation, the self-locking unit 620 of the self-locking module 220 can be specifically used to extend the effective level duration of the trip control signal based on the power provided by the energy storage module 210. The output signal of the self-locking unit 620 can be the output signal of the self-locking module 220.

[0118] In some embodiments, the self-locking unit 620 may be implemented based on a digital logic latch such as a D flip-flop and / or an SR flip-flop, that is, the self-locking unit 620 may include a D flip-flop and / or an SR flip-flop, etc.

[0119] Figure 8 , Fig. 9 , Fig.10 and Fig.11 The following are four timing diagrams of the operation of the self-locking module 220. When the target switch S1 is high level effective, the timing of the operation of the filter unit 610 and the self-locking unit 620 in the self-locking module 220 is as follows: Figure 8 and Fig. 9 When the target switch S1 is low level effective, the timing of the operation of the filter unit 610 and the self-locking unit 620 in the self-locking module 220 is as follows: Fig.10 and Fig.11 shown.

[0120] like Figure 8 As shown, y 1 is the input signal of the self-locking module 220, y 2 for y 1 is the output signal after being processed by the filter unit 610, y 3 for y 2 is the output signal of the self-locking module 220 obtained after being processed by the self-locking unit 620. The sampling control module 315 t 1, a trip control signal is sent out and input to the self-locking module 220. After being processed by the filtering unit 610, the self-locking unit 620 immediately outputs a corresponding high-level signal. The electric energy of the sampling control module 315 is t2 Moment is exhausted, the trip control signal cannot maintain a high level, y 1 and y 2 cannot be maintained and restored to a low level, but through the processing of the self-locking unit 620, under the action of the self-locking unit 620, y 3 can still maintain a high level; t At time 3, the electric energy stored in the energy storage module 210 is consumed. y 3 eventually returns to a low level signal.

[0121] It can be understood that even if the effective level of the trip control signal is maintained for only T 1, but under the action of the self-locking unit 620, y 3 The duration of the effective level can be extended to T 2. Among them, T 2 can be determined by the electric energy stored in the energy storage module 210. If the energy storage module 210 can continuously supply power to the self-locking module 220, then y 3 can always maintain a high level. In the case where the sampling control signal is not processed by the self-locking module 220 and directly drives the target switch S1, if the effective level of the sampling control signal is maintained for only T 1, T 1 is less than the minimum pulse width time of the tripper 311, the tripper 311 is at great risk and cannot stably complete the tripping action. The effective level duration of the sampling control signal is extended by the self-locking unit 620 (by T 1Extended to T 2, T 1< T 2, T 2 is greater than the minimum pulse width time of the release 311), the output signal of the self-locking module 220 y 3 driving the target switch S1, it can ensure the effective level for driving the target switch S1 ( Figure 8 The duration of the high level in the middle ensures that the releaser 311 can stably complete the tripping action.

[0122] Fig. 9 The situation where the trip control signal has high-frequency interference signals is taken into account. Fig. 9 As shown, y 1 is the input signal of the self-locking module 220, y 2 for y 1 is the output signal after being processed by the filter unit 610, y 3 for y 2 The output signal of the self-locking module 220 obtained after being processed by the self-locking unit 620. y When there is a high-frequency interference signal in 1, the filter unit 610 (showing a low-pass filter characteristic) can effectively filter outy 1, so the high-frequency interference signal y 2, there is no high-frequency signal, that is, the high-frequency interference signal will not be input into the self-locking unit 620, so the releaser will not trip by mistake.

[0123] Similarly, if Fig.10 As shown, y 1 is the input signal of the self-locking module 220, y 2 for y 1 is the output signal after being processed by the filter unit 610, y 3 for y 2 is the output signal of the self-locking module 220 obtained after being processed by the self-locking unit 620. The sampling control module 315 t 1, a trip control signal is sent to the self-locking module 220, and after being processed by the filtering unit 610, the self-locking unit 620 immediately outputs a corresponding low-level signal; the electric energy of the sampling control module 315 is t 2 Moment is exhausted, the trip control signal cannot maintain a high level, y 1 and y 2 cannot be maintained and restored to a low level, but through the processing of the self-locking unit 620, under the action of the self-locking unit 620, y 3 can still maintain a low level; t At time 3, the electric energy stored in the energy storage module 210 is consumed. y 3 is finally restored to a low level signal. The effective level duration of the sampling control signal is extended by the self-locking unit 620 (by T 1Extended to T 2, T 1< T 2, T 2 is greater than the minimum pulse width time of the release 311), the output signal of the self-locking module 220 y 3 driving the target switch S1, it can ensure the effective level for driving the target switch S1 ( Fig.10 The duration of the tripping time (in which the level is low) ensures that the tripping device 311 can stably complete the tripping action.

[0124] Fig.11 The situation where the trip control signal has high-frequency interference signals is taken into account. Fig.11 As shown, y 1 is the input signal of the self-locking module 220, y 2 for y 1 is the output signal after being processed by the filter unit 610, y 3 for y 2 The output signal of the self-locking module 220 obtained after being processed by the self-locking unit 620. yWhen there is a high-frequency interference signal in 1, the filter unit 610 (showing a low-pass filter characteristic) can effectively filter out y 1, so the high-frequency interference signal y 2, there is no high-frequency signal, that is, the high-frequency interference signal will not be input into the self-locking unit 620, so the releaser will not trip by mistake.

[0125] According to the switch control circuit provided in the embodiment of the present application, the pulses with a duration less than a preset duration are filtered out by the self-locking module, so that interference signals generated by the extremely large current change rate (di / dt) and voltage change rate (dv / dt) generated by the rapid action of the power switch tube in the power module of the inverter can be filtered out, thereby avoiding malfunction of the release and avoiding disconnection of the DC switch due to malfunction, thereby improving the reliability of the operation of the release.

[0126] In some embodiments, Fig.12 As shown, the self-locking module 220 includes: a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, a second capacitor C2, a first switch tube Q1 and a second switch tube Q2.

[0127] In actual implementation, in addition to Figure 7 In addition to the embodiment shown, the self-locking module 220 can also combine the filtering function and the self-locking function. The filtering function refers to the function of filtering out pulses whose duration is less than a preset duration. The self-locking function refers to the function of extending the effective level duration of the trip control signal based on the electric energy provided by the energy storage module 210.

[0128] An implementation method of combining the filtering function and the self-locking function of the self-locking module 220 can be as follows Fig.12 The working sequence of the self-locking module 220 can be referred to Fig.10 The self-locking module 220 may be composed of a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, a second capacitor C2, a first switch tube Q1, and a second switch tube Q2.

[0129] The first end of the first resistor R1 is connected to the input end of the self-locking module 220; the second end of the first resistor R1 is connected to the first end of the second resistor R2 and the second end of the second switch tube Q2;

[0130] The second end of the second resistor R2 is connected to the first end of the first switch tube Q1 and the first end of the first capacitor C1;

[0131] The third end of the first switch tube Q1 and the second end of the first capacitor C1 are grounded;

[0132] The second end of the first switch tube Q1 is connected to the first end of the fourth resistor R4;

[0133] The second end of the fourth resistor R4 is connected to the first end of the second switch tube Q2, the first end of the second capacitor C2, and the first end of the fifth resistor R5;

[0134] A first end of the third resistor R3 is connected to a third end of the second switch tube Q2 and a second end of the second capacitor C2;

[0135] The second end of the third resistor R3 and the second end of the fifth resistor R5 are connected to the power supply Vcc.

[0136] In actual implementation, the first switch tube Q1 may be an NPN transistor, and the second switch tube Q2 may be a PNP transistor. The first end, the second end, and the third end of the first switch tube Q1 and the second switch tube Q2 are the base, the collector, and the emitter, respectively. It should be noted that the power supply Vcc is the energy storage module 210.

[0137] exist y 1 is high level ( t 1), the first switch tube Q1 is turned on, the base of the second switch tube Q2 is at a low level, the second switch tube Q2 is also in the on state, and the self-locking module 220 outputs a low level. y 1 becomes low level when ( t 2), since the first switch tube Q1 and the second switch tube Q2 are still in the on state, the base of the first switch tube Q1 is pulled up to a high level and still maintains the on state, so the output of the self-locking module 220 remains at a low level.

[0138] The filtering function of the self-locking module 220 has the function of filtering out high-frequency interference signals. The input signal of the self-locking module 220 is In the case of, the self-locking module 220 latches the signal and stably outputs a low-level valid signal (when the target switch S1 is low-level valid), then the effective level duration of the trip control signal T 1The following conditions must be met:

[0139] (7).

[0140] in, u e1 Indicates the minimum threshold voltage for the first switch tube Q1 to be turned on; u e2 Indicates the minimum threshold voltage for the second switch tube Q2 to be turned on; Indicates the amplitude of the input voltage of the trip control signal (including the high level amplitude of the interference signal); Represents the supply voltage of the self-locking module 220 , that is, the voltage output by the energy storage module 210 to the self-locking module 220 .

[0141] According to formula (7), the effective level duration of the trip control signal issued by the sampling control module 315 is T 1 needs to satisfy formula (7) to successfully control the release 311 to disconnect; and the high-frequency pulse interference signal with a duration shorter than the time length represented by the right side of the greater than sign in formula (7) will be filtered out by the filtering function and will not cause the release 311 to disconnect (i.e., trip) by mistake.

[0142] In some embodiments, the first switch tube Q1 may be an NMOS, and the second switch tube Q2 may be a PMOS. The first end, the second end, and the third end of the first switch tube Q1 and the second switch tube Q2 are the gate, the drain, and the source, respectively. In this case, the on-off state of the first switch tube Q1 and the second switch tube Q2 is the same as the case where the first switch tube Q1 is an NPN-type triode and the second switch tube Q2 is a PNP-type triode. The working process of the self-locking module 220 in this case will not be described here.

[0143] According to the switch control circuit provided in the embodiment of the present application, the pulses with a duration less than a preset duration are filtered out by the self-locking module, so that interference signals generated by the extremely large current change rate (di / dt) and voltage change rate (dv / dt) generated by the rapid action of the power switch tube in the power module of the inverter can be filtered out, thereby avoiding malfunction of the release and avoiding disconnection of the DC switch due to malfunction, thereby improving the reliability of the operation of the release.

[0144] In some embodiments, reference Figures 13 to 16 The energy storage module 210 includes an energy storage unit and a switch unit for connecting the energy storage unit to a target power source.

[0145] In actual implementation, the energy storage unit is specifically used to implement the energy storage function and the power supply function in the energy storage module 210. The energy storage unit and the target power supply can be connected through a switch unit. The connection between the energy storage unit and the target power supply can be controlled by the switch state of the switch unit. When the switch unit is in the on state, the energy storage unit is connected to the target power supply, and electric energy can be transmitted from the target power supply to the energy storage unit; when the switch unit is in the off state, the connection between the energy storage unit and the target power supply is disconnected, and no electric energy is transmitted between them.

[0146] The energy storage unit is used to store electric energy based on the power supply of the target power source and to supply power to the self-locking module 220 based on the stored electric energy.

[0147] In actual implementation, the energy storage unit can be specifically used to realize the energy storage function and the power supply function. The electric energy provided by the target power supply to the energy storage module 210 can be stored by the energy storage unit. The electric energy stored in the energy storage unit can supply power to the self-locking module 220.

[0148] In some embodiments, the electric energy stored in the energy storage unit can also supply power to the target switch S1 and the release 311. That is, compared with the way in which the power supply module in the traditional inverter directly supplies power to the target switch S1 and the release, in the embodiment of the present application, the target switch S1 and the release 311 can be powered by the energy storage unit in the energy storage module 210 based on the electric energy stored in the energy storage unit.

[0149] In some embodiments, the energy storage unit may include a voltage-type energy storage element and / or a current-type energy storage element. The voltage-type energy storage element and / or the current-type energy storage element are the core energy storage elements in the energy storage unit.

[0150] In some embodiments, the voltage-type energy storage element may include a capacitor module and / or a battery. In some embodiments, the capacitor module includes at least one supercapacitor.

[0151] When there is an abnormality in the power supply from the target power source to the energy storage module 210 , the switch unit disconnects the energy storage unit from the target power source.

[0152] In actual implementation, the role of the switch unit is to prevent the electric energy stored in the energy storage unit from being released or consumed by the subsequent load (such as the load of the target power supply). In the case that the target power supply is powered off or fails to work, the energy storage unit still stores enough electric energy to maintain the operation of the self-locking module 220, the target switch S1 and the release 311. The switch unit can make the electric energy stored in the energy storage unit only be used by the self-locking module 220, the target switch S1 and the release 311, and will not be consumed by the load of the target power supply, which can ensure the independence and backup of the energy storage unit.

[0153] According to the switch control circuit provided in the embodiment of the present application, when there is an abnormality in the power supply from the target power supply to the energy storage module, the switch unit disconnects the connection between the energy storage unit and the target power supply. The electric energy stored in the energy storage module will not be consumed by the subsequent load, thereby ensuring that the electric energy stored in the energy storage module is used to enable the releaser to complete the tripping action.

[0154] In some embodiments, the switching unit includes a diode.

[0155] In actual implementation, the switching unit may include a diode, which utilizes the unidirectional conduction characteristics of the diode to disconnect the connection between the energy storage unit and the target power supply when there is an abnormality in the power supply from the target power supply to the energy storage module 210, and maintain the connection between the energy storage unit and the target power supply when the power supply from the target power supply to the energy storage module 210 is normal.

[0156] In some embodiments, reference Fig.13 and Fig.14, the energy storage unit may include an energy storage element C. The energy storage element C may be a voltage type energy storage element such as a traditional capacitor, a super capacitor or a lithium ion battery. The switch unit position may include Fig.13 and Fig.14 The switching unit may include a diode D1.

[0157] When the target power supply operates normally (i.e., can supply power to the energy storage module 210 normally), the target power supply can charge the energy storage element C in the energy storage unit through the diode D1 (the diode D1 is turned on at this time) until the voltage of the energy storage element C rises to the corresponding output voltage of the target power supply. When there is an abnormality in the power supply of the target power supply to the energy storage module 210 (such as power failure or failure to work due to a fault), the energy storage element C still stores enough electric energy to maintain the operation of the self-locking module 220, the target switch S1 and the release 311. At this time, the diode D1 is turned off, so that the electric energy stored in the energy storage element C can only be used by the self-locking module 220, the target switch S1 and the release 311, and will not be consumed by the load of the target power supply.

[0158] In some embodiments, reference Fig.13 The positive electrode of the target power source can be connected to the energy storage unit through the switch unit. In the case where the switch unit includes a diode D1, the positive electrode of the diode D1 is connected to the positive electrode of the target power source, and the negative electrode of the diode D1 is connected to the energy storage unit.

[0159] In some embodiments, reference Fig.14 The energy storage unit may be connected to the negative electrode of the target power source through the switch unit. When the switch unit includes a diode D1, the positive electrode of the diode D1 is connected to the energy storage unit, and the negative electrode of the diode D1 is connected to the negative electrode of the target power source.

[0160] According to the switch control circuit provided in the embodiment of the present application, when there is an abnormality in the power supply from the target power supply to the energy storage module, the switch unit disconnects the connection between the energy storage unit and the target power supply. The electric energy stored in the energy storage module will not be consumed by the subsequent load, thereby ensuring that the electric energy stored in the energy storage module is used to enable the releaser to complete the tripping action.

[0161] In some embodiments, the energy storage unit includes a voltage-type energy storage element.

[0162] In actual implementation, the energy storage unit may use a voltage-type energy storage element to store electrical energy.

[0163] The switch unit includes a first switch sub-unit and a second switch sub-unit; the first switch sub-unit and the second switch sub-unit are connected in parallel; the first switch sub-unit and the second switch sub-unit are both used to connect the target power supply and the energy storage unit.

[0164] In actual implementation, the switch unit may include a first switch subunit and a second switch subunit. The first switch subunit and the second switch subunit are in parallel and are both used to connect the target power source and the energy storage unit. The switch unit position may include: Fig.15 and Fig.16 The form shown, etc.

[0165] When the target power supply to the energy storage module 210 is normal and the voltage of the energy storage unit is lower than the first threshold, the first switch subunit is turned on; when the target power supply to the energy storage module 210 is normal and the voltage of the energy storage unit is higher than the second threshold, the first switch subunit is turned off; when there is an abnormality in the power supply to the energy storage module 210 by the target power supply, the second switch subunit is turned off after the first switch subunit is turned off; the second threshold is greater than the first threshold.

[0166] In actual implementation, the second switch subunit may be equivalent to Fig.13 and Fig.14 When the second switch subunit is in the on state, the energy storage unit is connected to the target power source, and electric energy can be transmitted from the target power source to the energy storage unit; when the second switch subunit is in the off state, a connection path between the energy storage unit and the target power source is disconnected.

[0167] In some embodiments, the second switch subunit may include the aforementioned diode D1.

[0168] In some embodiments, the first switch subunit may include any type of switch tube, such as Fig.15 and Fig.16 The switch tube Q3 is shown.

[0169] refer to Fig.15 , the positive electrode of the target power supply can be connected to the energy storage unit through the switch unit. The positive electrode of the diode D1 is connected to the positive electrode of the target power supply, and the negative electrode of the diode D1 is connected to the energy storage unit. In the case where the switch tube Q3 is an IGBT, the emitter of the switch tube Q3 is connected to the energy storage unit, and the collector of the switch tube Q3 is connected to the positive electrode of the target power supply.

[0170] refer to Fig.16 The energy storage unit can be connected to the negative electrode of the target power supply through the switch unit. The positive electrode of the diode D1 is connected to the energy storage unit, and the negative electrode of the diode D1 is connected to the negative electrode of the target power supply. When the switch tube Q3 is an IGBT, the collector of the switch tube Q3 is connected to the energy storage unit, and the emitter of the switch tube Q3 is connected to the positive electrode of the target power supply.

[0171] It can be understood that, in the case where the first switch subunit includes other types of switch tubes except the NPN type transistor, the connection relationship between the switch tube and the energy storage unit and the target power supply can refer to Fig.15 and Fig.16 get.

[0172] like Fig.15 and Fig.16 The working process of the energy storage module 210 shown may include:

[0173] When the target power supply is operating normally (i.e., it can supply power to the energy storage module 210 normally), the sampling control module 315 can detect the voltage of the energy storage unit; when the voltage of the energy storage unit is lower than the first threshold, the sampling control module 315 can control the first switch subunit to be turned on (e.g., control the switch tube Q3 to be attracted, etc.), and the target power supply charges the energy storage unit; when the voltage of the energy storage unit is higher than the second threshold (it can be understood that the second threshold is greater than the first threshold), the sampling control module 315 can control the first switch subunit to be disconnected (e.g., control the switch tube Q3 to be disconnected, etc.), and the target power supply stops charging the energy storage unit. When the target power supply to the energy storage module 210 is abnormal (e.g., power failure or failure to work due to a fault), since the residual power stored in the sampling control module 315 is relatively small, the first switch subunit is disconnected first, cutting off the discharge path of the rear stage of the energy storage module 210, and only allowing the energy storage module 210 to supply power to the self-locking module 220, the target switch S1 and the release 311.

[0174] Compared to Fig.13 and Fig.14 ,like Fig.15 and Fig.16 The advantage of the embodiment shown is that the conduction voltage drop of the diode D1 can be reduced, so that the voltage of the energy storage unit can be closer to the output voltage of the target power supply, so that the energy storage unit can store more energy. The capacitor energy is (1 / 2)*C*U 2 , and U 2 is proportional to (where C represents the capacitance of the capacitor and U represents the voltage across the capacitor).

[0175] According to the switch control circuit provided in the embodiment of the present application, when there is an abnormality in the power supply from the target power supply to the energy storage module, the switch unit disconnects the connection between the energy storage unit and the target power supply. The electric energy stored in the energy storage module will not be consumed by the subsequent load, which can ensure that the electric energy stored in the energy storage module is used to enable the releaser to complete the tripping action. It can also make the voltage of the energy storage unit closer to the output voltage of the target power supply, store more electric energy, and further improve reliability.

[0176] In some embodiments, the first switch subunit includes a fully controllable device.

[0177] In actual implementation, the first switch subunit may be a fully controllable device.

[0178] According to the switch control circuit provided in the embodiment of the present application, a fully-controlled device is adopted in the first switch sub-unit, which has higher flexibility and controllability.

[0179] In some embodiments, the fully-controlled device includes at least one of an IGBT, a MOSFET, a triode, and a relay.

[0180] In actual implementation, the fully-controlled device used by the first switch sub-unit may include at least one of an IGBT, a MOSFET, a triode, and a relay.

[0181] According to the switch control circuit provided in the embodiment of the present application, the first switch sub-unit adopts fully controlled devices such as IGBT, MOSFET, triode or relay, which has higher flexibility and controllability.

[0182] The present application also provides an inverter. Figure 3 , Figure 6 , Figures 12 to 16 , the inverter 310 may include: a target switch S1, a DC switch 312, a tripper 311, and a switch control circuit 316;

[0183] A switch control circuit 316, used to control the target switch S1;

[0184] When the target switch S1 is disconnected, the tripping device 311 performs a tripping action to disconnect the DC switch 312 .

[0185] The working process of the inverter and the target switch S1, DC switch 312, release 311, switch control circuit 316, etc. included in the inverter can be referred to the above embodiments, which will not be repeated here.

[0186] According to the inverter provided in the embodiment of the present application, the energy storage module stores electric energy based on the power supply of the target power supply and supplies power to the self-locking module based on the stored electric energy. The self-locking module latches the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected, so that the releaser completes the tripping action. Under the joint action of the energy storage module and the self-locking module, it can be achieved that when the power supply module or the sampling control module is abnormal and can only send a single tripping control signal, the signal obtained by latching the single tripping control signal is still sufficient to drive the target switch to be disconnected, so that the releaser completes the tripping action. The risk of not being able to stably and reliably trip when the power supply module or the sampling control module is abnormal can be at least reduced or even completely solved, the reliability of switch control can be improved, the possibility of the spread of faults such as short circuit or DC arc of photovoltaic components can be reduced, and the safety and reliability of the inverter and photovoltaic power generation system can be improved.

[0187] The present application also provides a photovoltaic power generation system. Figure 3 , Figure 6 , Figures 12 to 16 The photovoltaic power generation system may include: a photovoltaic component 320 and an inverter 310 .

[0188] The working process of the photovoltaic power generation system and the photovoltaic assembly 320 and the inverter 310 included in the photovoltaic power generation system can be referred to the above embodiments, which will not be described again here.

[0189] According to the photovoltaic power generation system provided by the embodiment of the present application, the energy storage module stores electric energy based on the power supply of the target power supply and supplies power to the self-locking module based on the stored electric energy. The self-locking module latches the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected, so that the releaser completes the tripping action. Under the joint action of the energy storage module and the self-locking module, it can be achieved that when the power supply module or the sampling control module is abnormal and can only send a single tripping control signal, the signal obtained by latching the single tripping control signal is still sufficient to drive the target switch to be disconnected, so that the releaser completes the tripping action. The risk of not being able to stably and reliably trip when the power supply module or the sampling control module is abnormal can be at least reduced or even completely solved, the reliability of switch control can be improved, the possibility of the spread of faults such as short circuit or DC arc of photovoltaic components can be reduced, and the safety and reliability of the inverter and the photovoltaic power generation system can be improved.

[0190] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0191] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0192] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0193] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0194] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A switch control circuit, characterized in that: include: Energy storage module and self-locking module; The energy storage module is used to store electric energy based on the power supply of the target power supply and to supply power to the self-locking module based on the stored electric energy; The self-locking module is used to latch the input tripping control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected so that the releaser completes the tripping action; The self-locking module is specifically used to extend the effective level duration of the trip control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected; The self-locking module includes: a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor, a second capacitor, a first switch tube and a second switch tube; The first end of the first resistor is connected to the input end of the self-locking module; the second end of the first resistor is connected to the first end of the second resistor and the second end of the second switch tube; The second end of the second resistor is connected to the first end of the first switch tube and the first end of the first capacitor; The third end of the first switch tube and the second end of the first capacitor are grounded; The second end of the first switch tube is connected to the first end of the fourth resistor; The second end of the fourth resistor is connected to the first end of the second switch tube, the first end of the second capacitor, and the first end of the fifth resistor; The first end of the third resistor is connected to the third end of the second switch tube and the second end of the second capacitor; The second end of the third resistor and the second end of the fifth resistor are connected to a power supply.

2. The switch control circuit according to claim 1, characterized in that: The self-locking module is also used to filter out pulses whose duration is less than a preset duration.

3. The switch control circuit according to claim 2, characterized in that: The self-locking module comprises a filtering unit and a self-locking unit; The input signal of the self-locking module is processed by the filtering unit and then input into the self-locking unit; The filtering unit is used to filter out pulses with a duration shorter than a preset duration; The self-locking unit is used to extend the effective level duration of the trip control signal based on the electric energy provided by the energy storage module to control the target switch to be disconnected.

4. The switch control circuit according to any one of claims 1 to 3, characterized in that: The energy storage module includes an energy storage unit and a switch unit for connecting the energy storage unit to the target power source; The energy storage unit is used to store electric energy based on the power supply of the target power supply and to supply power to the self-locking module based on the stored electric energy; When there is an abnormality in the power supply from the target power source to the energy storage module, the switch unit disconnects the energy storage unit from the target power source.

5. The switch control circuit according to claim 4, characterized in that: The energy storage unit includes a voltage-type energy storage element; The switch unit includes a first switch subunit and a second switch subunit; the first switch subunit and the second switch subunit are connected in parallel; the first switch subunit and the second switch subunit are both used to connect the target power supply and the energy storage unit; When the target power supply to the energy storage module is normal and the voltage of the energy storage unit is lower than a first threshold, the first switch subunit is turned on; when the target power supply to the energy storage module is normal and the voltage of the energy storage unit is higher than a second threshold, the first switch subunit is turned off; when the target power supply to the energy storage module is abnormal, the second switch subunit is turned off after the first switch subunit is turned off; The second threshold is greater than the first threshold.

6. The switch control circuit according to claim 5, characterized in that: The first switch subunit includes a fully controllable device.

7. The switch control circuit according to claim 6, characterized in that: The fully controlled device includes at least one of an IGBT, a MOSFET, a triode and a relay.

8. The switch control circuit according to claim 4, characterized in that: The switch unit includes a diode.

9. An inverter, characterized in that: include: A target switch, a DC switch, a release, and a switch control circuit as claimed in any one of claims 1 to 8; The switch control circuit is used to control the target switch; When the target switch is disconnected, the releaser completes the tripping action to disconnect the DC switch.

10. A photovoltaic power generation system, characterized in that: include: A photovoltaic module and an inverter as claimed in claim 9.

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