Photovoltaic loss reduction device, switching-on control method, electronic equipment and storage medium

Abstract

The embodiment of the invention provides a photovoltaic loss reduction device, a switching-on control method, electronic equipment and a storage medium, and belongs to the technical field of circuit breaker switching-on. The device comprises a vacuum circuit breaking module, an inrush current suppression module and an overvoltage limiting module. Step-by-step closing of the inrush current suppression module is controlled at an optimal closing phase angle before closing and pre-discharging of the vacuum circuit breaking module, step-by-step control is performed on primary on-off of a load and an external photovoltaic power grid, steady-state closing of the vacuum circuit breaking module is realized, and a large-scale photovoltaic power station is basically free of inrush current during no-load closing and directly enters steady-state excitation current; the overvoltage generated by the vacuum circuit breaking module is limited through the overvoltage limiting module, and the problem of overvoltage caused by reignition of the circuit breaking module when the capacitor is cut off is effectively solved. During power generation in the daytime, the photovoltaic power grid and the load power grid are subjected to accurate phase selection closing or non-impact access, so that the off-grid no-load loss of the photovoltaic power station which does not generate power at night and in rainy days is effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of circuit breaker closing, and in particular to a photovoltaic loss reduction device and closing control method, electronic equipment, and storage medium. Background Art

[0002] In the related art, the closing inrush current of a large photovoltaic power station is the largest when the voltage is 0° and the closing inrush current is the smallest when the voltage is 90°. However, when the large photovoltaic power station is disconnected from the grid at night or on rainy days, and when the photovoltaic power station is randomly connected to the grid during the day, a huge impact inrush current will be generated, causing great damage to the power system. Therefore, in order to avoid the above situation, the existing large photovoltaic power station is connected to the grid for a long time, which will cause the large photovoltaic power station to consume a large amount of no-load loss when disconnected from the grid in some cases. However, the existing closing inrush current suppression method of adding a phase-selective closing device to the transformer incoming circuit breaker is not ideal. The residual magnetism of the transformer and the mechanical characteristics of the circuit breaker are highly dispersed, and the random influence of the closing pre-discharge fails to play the role of phase-selective closing, so that a large excitation inrush current is still generated at the moment of no-load closing of the transformer. Summary of the Invention

[0003] The main purpose of the embodiments of the present application is to provide a photovoltaic loss reduction device and a closing control method, an electronic device, and a storage medium to achieve inrush-free access to the power grid.

[0004] To achieve the above objectives, an embodiment of the present application provides a photovoltaic loss reduction device, comprising:

[0005] A vacuum circuit breaker module, the vacuum circuit breaker module is connected to the external photovoltaic grid and the load, and the vacuum circuit breaker module is used to control the on-off switching between the load and the external photovoltaic grid;

[0006] an inrush current suppression module, the inrush current suppression module being connected in parallel with the vacuum circuit breaker module and configured to control the initial on / off of the load and the external photovoltaic power grid in steps before the vacuum circuit breaker module performs a conduction action;

[0007] An overvoltage limiting module is located between the vacuum circuit breaker module and the inrush current suppression module. The overvoltage limiting module is connected in parallel with the inrush current suppression module and the vacuum circuit breaker module respectively. The inrush current suppression module is used to limit the overvoltage generated by the vacuum circuit breaker module.

[0008] Furthermore, the inrush current suppression module includes:

[0009] A three-phase closer, connected in parallel with the vacuum circuit breaker module, for regulating the initial on-off of the load and the external photovoltaic power grid;

[0010] A phase controller is connected to the three-phase closer via an optical fiber, and is used to regulate the three-phase closer in steps before the vacuum circuit breaker module performs a conduction action.

[0011] Furthermore, the vacuum circuit breaker module includes:

[0012] an epoxy resin sleeve, wherein the inrush current suppression module and the overvoltage limiting module are sleeved in the epoxy resin sleeve;

[0013] A vacuum interrupter, wherein the vacuum interrupter is sleeved in the epoxy resin sleeve, the inrush current suppression module is provided on one side of the vacuum interrupter, the overvoltage limiting module is provided on the other side of the vacuum interrupter, and both ends of the fracture of the vacuum interrupter are connected in parallel with the inrush current suppression module and the overvoltage limiting module respectively;

[0014] Wherein, the vacuum interrupter and the overvoltage limiting module are integrally installed in the epoxy resin sleeve.

[0015] Furthermore, the overvoltage limiting module includes:

[0016] A single-phase limiting unit, wherein each phase of the single-phase limiting unit is connected in parallel with the inrush current suppression module and the vacuum circuit breaker module, and each phase of the single-phase limiting unit includes a plurality of nonlinear resistors;

[0017] Wherein, a plurality of the nonlinear resistors are connected in series to form a plurality of series sub-columns, and a plurality of the series sub-columns are connected in parallel to form the single-phase limiting unit.

[0018] Another aspect of the present invention provides a method for controlling the closing of a photovoltaic loss reduction device, wherein the photovoltaic loss reduction device includes a vacuum circuit breaker module and an inrush current suppression module. The method includes:

[0019] Detect the current status of the vacuum breaker module and the inrush current suppression module;

[0020] When the vacuum circuit breaker module is in an open state and the inrush current suppression module is in an off state, determining whether an access instruction sent by an external photovoltaic power grid is received;

[0021] When the access instruction is received, the inherent closing time of the vacuum circuit breaker module and the current grid voltage of the external photovoltaic grid are acquired, and a closing instruction is output to the vacuum circuit breaker module;

[0022] According to the current grid voltage and the inherent closing time, before the vacuum circuit breaker module performs the conduction action, the inrush current suppression module is controlled to close in steps, so as to control the initial conduction between the load and the external photovoltaic grid in steps;

[0023] According to the closing instruction, the vacuum circuit breaker module is controlled to switch from the open state to the closed state, and the load and the external photovoltaic power grid are connected again.

[0024] Furthermore, the inrush current suppression module includes a three-phase closer, and the step-by-step control of closing the inrush current suppression module includes:

[0025] Determine, based on the current grid voltage, a first closing time from the current AB phase voltage to the nearest grid voltage peak point, and a second closing time from the current C phase voltage to the nearest grid voltage peak point in the three-phase closer;

[0026] When the first closing time is the same as the inherent closing time, the A-phase closer and the B-phase closer in the three-phase closer are driven to close simultaneously to perform preliminary closing.

[0027] Furthermore, the step-by-step control of closing the inrush current suppression module includes:

[0028] According to the second closing time, when the current C-phase voltage reaches the nearest grid voltage peak point, the C-phase closer in the three-phase closer is driven to close, so as to perform a further closing.

[0029] Furthermore, the method further comprises:

[0030] When it is determined that the vacuum circuit breaker module is in the closed state, the A-phase closer, the B-phase closer and the C-phase closer in the three-phase closer are driven to open simultaneously, so that the inrush current suppression module is in the closed state.

[0031] To achieve the above-mentioned purpose, another aspect of an embodiment of the present application provides an electronic device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor implements the above-mentioned method when executing the computer program.

[0032] To achieve the above-mentioned purpose, another embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program implements the above-mentioned method when executed by a processor.

[0033] The embodiments of the present application include at least the following beneficial effects: The present application provides a photovoltaic loss reduction device and closing control method, electronic device, and storage medium. This solution controls the step-by-step closing of the inrush current suppression module at the optimal closing phase angle before the vacuum breaker module closes and pre-discharges, performing step-by-step control of the initial connection and disconnection between the load and the external photovoltaic grid. This achieves steady-state closing of the vacuum breaker module, ensuring that no-load closing of large photovoltaic power stations is essentially inrush-free and directly enters a steady-state excitation current state. This overcomes the problem of poor closing inrush current performance in existing phase-selective closing devices and phase-controlled circuit breakers due to the large dispersion of circuit breaker mechanical characteristics and the randomness of closing pre-discharge. Furthermore, the overvoltage limiting module limits the overvoltage generated by the vacuum breaker module, effectively resolving the problem of reignition overvoltage in the breaker module when removing capacitors. This effectively reduces no-load losses in photovoltaic power stations during nighttime and rainy days when they are not generating electricity. This solution enables overvoltage-free disconnection between the photovoltaic grid and the load grid when large photovoltaic power stations are not generating electricity at night or on rainy days, and precise phase selection for closing or surge-free connection between the photovoltaic grid and the load grid during daytime power generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A topological diagram of a photovoltaic loss reduction device provided in an embodiment of the present application;

[0035] Figure 2 A schematic structural diagram of a photovoltaic loss reduction device provided in an embodiment of the present application;

[0036] Figure 3 This is a flow chart of a method for controlling the closing of a photovoltaic loss reduction device provided in an embodiment of the present application;

[0037] Figure 4 This is a schematic diagram of the hardware structure of the electronic device provided in an embodiment of the present application.

[0038] Reference numerals: vacuum circuit breaker module 100 , inrush current suppression module 200 , overvoltage limiting module 300 , epoxy resin sleeve 110 , vacuum interrupter 120 . DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the embodiments of the present application. They are merely examples of devices and methods consistent with some aspects of the embodiments of the present application as detailed in the appended claims.

[0040] It will be understood that the terms "first", "second", etc. used in this application may be used herein to describe various concepts, but unless otherwise specified, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the words "if" and "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0041] The terms "at least one", "plurality", "each", "any", etc. used in this application include "at least one", "two" or more, "plurality" or "each", "any" or "any one", "each" or "any one" as used herein.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing the embodiments of this application only and are not intended to limit this application.

[0043] Before explaining the embodiments of the present application in detail, some of the nouns and terms involved in the embodiments of the present application are first explained. The nouns and terms involved in the embodiments of the present application are subject to the following explanations.

[0044] Large photovoltaic power station transformers generate huge inrush currents due to random phase angle closing. The transformer closing inrush current expression is as follows:

[0045]

[0046] If t = 0, the closing angle φ = 90°, u = Um, that is, closing at the peak position of the grid voltage Φ = Φ m This situation is identical to the steady-state situation, that is, a steady-state magnetic flux is established inside the core from the outset without any transients. When the transformer is connected to the grid, it enters the steady state directly without generating a large magnetizing inrush current.

[0047] If t = 0, the closing angle φ = 0°, u = 0, that is, the grid voltage is 0 and the closing angle Φ = Φ m [1-cos(ωt)]. In this case, the main flux initially increases from zero to 2Φm, adding a transient component. Only after this component decays can the transformer transition to steady-state operation. In this closing condition, the non-periodic flux reaches its maximum value, and the transient process is also the most intense. At this point, when the transformer is connected to the grid, a large magnetizing inrush current is generated.

[0048] In one embodiment of the present application, reference is made to Figure 1 and Figure 2 A photovoltaic loss reduction device includes: a vacuum circuit breaker module 100, a surge current suppression module 200 and an overvoltage limiting module 300.

[0049] The vacuum circuit breaker module 100, the inrush current suppression module 200, and the overvoltage limiting module 300 are connected in parallel. The vacuum circuit breaker module 100 is electrically connected to the external photovoltaic grid and the load. The vacuum circuit breaker module 100 can regulate the connection and disconnection between the load and the external photovoltaic grid to achieve control of reconnection and disconnection.

[0050] That is, the vacuum circuit breaker module 100 is electrically connected to the transformer in the photovoltaic power grid and the load power grid respectively. After the inrush current suppression module 200 performs the initial switching, the vacuum circuit breaker module 100 adjusts the switching between the load power grid and the transformer in the external photovoltaic power grid to achieve switching again.

[0051] The inrush current suppression module 200 is electrically connected to the vacuum circuit breaker module 100 in parallel, that is, the inrush current suppression module 200 is also electrically connected to the external photovoltaic grid and the load, respectively. The inrush current suppression module 200 can regulate the conduction of the external photovoltaic grid in steps before the vacuum circuit breaker module 100 performs the on-off action to achieve initial conduction.

[0052] That is, the inrush current suppression module 200 is electrically connected to the transformer in the photovoltaic power grid and the load power grid respectively. Before the vacuum circuit breaker module 100 performs switching, the inrush current suppression module 200 switches on or off the transformer in the load power grid and the external photovoltaic power grid in steps to achieve initial switching.

[0053] When disconnecting a capacitor bank, the reignition overvoltage caused by the circuit breaker reigniting can damage the capacitor inter-electrode insulation or even cause breakdown. The overvoltage limiting module 300 is disposed between the vacuum circuit breaker module 100 and the inrush current suppression module 200. The overvoltage limiting module 300 and the inrush current suppression module 200 are electrically connected in parallel, and the overvoltage limiting module 300 and the vacuum circuit breaker module 100 are also electrically connected in parallel. The overvoltage limiting module 300 can limit the overvoltage generated during the switching operation of the vacuum circuit breaker module 100.

[0054] This solution controls the inrush current suppression module 200 to close in stages at the optimal closing phase angle before the vacuum breaker module 100 closes and pre-discharges. This provides step-by-step control of the initial connection and disconnection between the load and the external photovoltaic grid, achieving steady-state closing of the vacuum breaker module 100. This ensures that no-load closing of large photovoltaic power plants is virtually inrush-free, allowing for direct steady-state magnetizing current flow. This overcomes the poor closing inrush current performance of existing phase-selective closing devices and phase-controlled circuit breakers, which are affected by the wide dispersion of mechanical characteristics of the circuit breakers and the randomness of closing pre-discharge. Furthermore, the overvoltage limiting module 300 limits the overvoltage generated by the vacuum breaker module 100, effectively resolving the issue of reignition overvoltage in the breaker module when capacitors are removed. This effectively reduces no-load losses during nighttime and rainy days when the photovoltaic power station is not generating electricity. This solution allows for overvoltage-free disconnection between the photovoltaic grid and the load grid during nighttime and rainy days, while enabling precise phase selection for closing or surge-free connection between the photovoltaic grid and the load grid during daytime power generation.

[0055] In an embodiment of one aspect of the present application, the inrush current suppression module 200 includes: a three-phase closer and a phase controller.

[0056] The three-phase closer is electrically connected to the vacuum circuit breaker module 100 in parallel. The three-phase closer can adjust the initial on-off of the load and the external photovoltaic grid, and realize the initial conduction of the transformer in the photovoltaic grid and the load grid.

[0057] The three-phase closer includes three single-phase closers, namely, phase A closer, phase B closer, and phase C closer. The three phases of the vacuum circuit breaker module 100 are electrically connected in parallel with the three single-phase closers in the three-phase closer.

[0058] The phase controller is electrically connected to the three-phase closer via an optical fiber. The phase controller can step-by-step regulate the three-phase closer to close and open at the optimal closing phase angle before the vacuum circuit breaker module 100 performs the on-off action, thereby achieving the initial conduction of the transformer and the load grid in the photovoltaic power grid.

[0059] The optimal closing phase angle is φ = 90°, which means closing at the peak of the grid voltage. The single-phase closer is a Spark closer.

[0060] In an embodiment of one aspect of the present application, a vacuum circuit breaker module 100 includes an epoxy resin sleeve 110 and a vacuum interrupter 120 .

[0061] The epoxy resin sleeve 110 is provided with a surge suppression module 200, a vacuum interrupter 120 and an overvoltage limiting module 300. A three-phase closer of the surge suppression module 200 is installed on one side of the vacuum interrupter 120, and three single-phase limiting units of the overvoltage limiting module 300 are installed on the other side of the vacuum interrupter 120.

[0062] Both ends of the break of the vacuum interrupter 120 are electrically connected in parallel to the three-phase closer of the surge suppression module 200 , and both ends of the break of the vacuum interrupter 120 are electrically connected in parallel to the three single-phase limiting units of the overvoltage limiting module 300 .

[0063] The vacuum interrupter 120 and the three single-phase limiting units of the overvoltage limiting module 300 are integrated into the epoxy resin sleeve 110 .

[0064] In an embodiment of one aspect of the present application, the overvoltage limiting module 300 includes: three single-phase limiting units.

[0065] Each single-phase limiting unit is electrically connected in parallel to the three single-phase closers in the three-phase closer, and each single-phase limiting unit is electrically connected in parallel to the three phases in the vacuum circuit breaker module 100.

[0066] That is, each single-phase limiting unit is electrically connected to a single-phase closer in parallel, and each single-phase limiting unit is electrically connected to one phase of the vacuum circuit breaker module 100 in parallel.

[0067] Each single-phase limiting unit includes a plurality of nonlinear resistors, which are electrically connected in series to form a plurality of series sub-columns, and the plurality of series sub-columns are electrically connected in parallel to form a single-phase limiting unit.

[0068] Wherein, the nonlinear resistor is a high-energy zinc oxide nonlinear resistor.

[0069] See also Figure 3 , Figure 3 This is an optional flow chart of a method for controlling the closing of a photovoltaic loss reduction device provided in an embodiment of the present application. Figure 3 The method may include but is not limited to steps S100 to S500, and may be applied to the above-mentioned photovoltaic loss reduction device, in which the photovoltaic power station does not generate electricity at night or on rainy days.

[0070] Step S100: detecting the current status of the vacuum breaker module and the inrush current suppression module.

[0071] Step S200: When the vacuum circuit breaker module is in the open state and the inrush current suppression module is in the off state, it is determined whether a connection instruction sent by the external photovoltaic power grid is received.

[0072] Step S300: When receiving the access instruction, the inherent closing time of the vacuum circuit breaker module and the current grid voltage of the external photovoltaic grid are obtained, and the closing instruction is output to the vacuum circuit breaker module.

[0073] Step S400 , based on the current grid voltage and the inherent closing time, before the vacuum circuit breaker module performs the conduction action, the inrush current suppression module is controlled to close in steps, so as to control the initial conduction between the load and the external photovoltaic grid in steps.

[0074] Step S500: According to the closing instruction, the vacuum circuit breaker module is controlled to switch from the open state to the closed state, and the load is connected to the external photovoltaic grid again.

[0075] In steps S100 to S500, as shown in the embodiment of the present application, the inrush current suppression module is controlled to close in stages at the optimal closing phase angle before the vacuum breaker module closes and pre-discharges, performing step-by-step control of the initial on-off between the load and the external photovoltaic grid. This achieves steady-state closing of the vacuum breaker module, ensuring that no-load closing of the large photovoltaic power station is essentially inrush-free and directly enters the steady-state excitation current. This overcomes the problem of poor closing inrush current performance caused by the large dispersion of the mechanical characteristics of the circuit breaker and the randomness of the closing pre-discharge in existing phase-selective closing devices and phase-controlled circuit breakers. The overvoltage limiting module limits the overvoltage generated by the vacuum breaker module, effectively solving the problem of reignition overvoltage in the breaker module when removing capacitors. This effectively reduces the no-load losses of the photovoltaic power station when it is not generating electricity at night or on rainy days. This allows the photovoltaic grid and the load grid to be disconnected without overvoltage when the large photovoltaic power station is not generating electricity at night or on rainy days, and allows the photovoltaic grid and the load grid to be precisely phase-selected for closing or connected without impact during daytime power generation.

[0076] In some embodiments of step S100 , the inrush current suppression module and the vacuum breaker module are initialized.

[0077] During daytime power generation on the external photovoltaic grid, the vacuum circuit breaker module, system PT, and inrush current suppression module are energized and draw energy from the system. The operating status of the vacuum circuit breaker module and the three-phase closer in the inrush current suppression module are detected.

[0078] In some embodiments of step S200, when the photovoltaic power grid does not generate electricity at night or on rainy days, the vacuum circuit breaker module in the photovoltaic loss reduction device is disconnected from the grid and is in an open state, and the three-phase closer in the inrush current suppression module is in an off state, effectively reducing a large amount of off-grid no-load losses when the photovoltaic power station does not generate electricity at night or on rainy days.

[0079] When the external photovoltaic grid is connected to the load grid, the external photovoltaic grid will send an access instruction to the photovoltaic loss reduction device to determine whether the access instruction is received.

[0080] In some embodiments of step S300 , when the access instruction is confirmed, a closing instruction is sent to the vacuum breaker module to obtain the inherent closing time initialized by the vacuum breaker module in S100 and the current grid voltage of the external photovoltaic grid.

[0081] In some embodiments of step S400, the closing time of the inrush current suppression module is determined according to the current grid voltage and the inherent closing time, and each phase closer of the three-phase closer in the inrush current suppression module is driven step by step to close the circuit in steps, connect the load and the external photovoltaic grid, and achieve initial closing.

[0082] The three-phase closers in the inrush current suppression module are driven in steps, which needs to be completed before the vacuum circuit breaker module performs the conduction action. The inrush current suppression module switches from the off state to the on state.

[0083] In some embodiments of step S500 , based on the initial closing of the inrush current suppression module, the vacuum circuit breaker module again connects the load to the external photovoltaic grid according to the closing instruction, and the vacuum circuit breaker module switches from the open state to the closed state.

[0084] Through the above scheme, the inrush current suppression module can calculate the optimal closing time according to the current grid voltage and the inherent closing time preset by the vacuum circuit breaker module. When the three phases of the inrush current suppression module are all energized, the vacuum circuit breaker module is driven to close. After an appropriate delay, the three-phase closer of the inrush current suppression module is triggered at the optimal closing phase angle φ=90° (i.e., the grid voltage peak position) before the vacuum breaker module is pre-discharged. This completely eliminates the factors of large dispersion of the mechanical characteristics of the circuit breaker and randomness of the closing pre-discharge, so that large-scale photovoltaic power stations are connected to the grid with basically no inrush current and no impact when closing at no load; the three-phase closer automatically exits operation after the closing circuit breaker action is completed.

[0085] In some embodiments of another aspect of the present application, in step S400, before the vacuum circuit breaker module performs a conduction action, the inrush current suppression module is controlled to close in steps according to the current grid voltage and the inherent closing time, specifically including:

[0086] Step S410, determining a first closing time from the current AB phase voltage to the nearest grid voltage peak point in the three-phase closer, and a second closing time from the current C phase voltage to the nearest grid voltage peak point, based on the current grid voltage;

[0087] Step S420: When the first closing time is the same as the inherent closing time, the A-phase closer and the B-phase closer of the three-phase closer are driven to close simultaneously to perform preliminary closing.

[0088] Step S430: According to the second closing time, when the current C-phase voltage reaches the nearest grid voltage peak point, the C-phase closer in the three-phase closer is driven to close, so as to close the circuit again.

[0089] In some embodiments of step S410, based on the current grid voltage, the first closing time of the three-phase closer A phase voltage and the B phase voltage from the nearest grid voltage peak point is calculated within 0.5 ms, and the second closing time of the three-phase closer C phase voltage from the nearest grid voltage peak point is calculated.

[0090] That is to say, according to the current grid voltage, the time for the AB phase voltage to reach the nearest 90° is calculated within 0.5ms, and the time for the C phase voltage to reach the nearest 90° is calculated.

[0091] Among them, the nearest 90° is the optimal closing phase angle, and the times are respectively the first closing time and the second closing time.

[0092] In some embodiments of step S420, it is determined whether the first closing time is consistent with the inherent closing time of the vacuum circuit breaker module.

[0093] If so, the A-phase closer and the B-phase closer in the three-phase closer are driven to close simultaneously, and the A-phase closer and the B-phase closer are closed in advance to achieve preliminary closing.

[0094] If not, the process returns to S410 and recalculates the first closing time until the first closing time is the same as the inherent closing time.

[0095] That is to say, when the time before the AB phase voltage reaches the nearest 90° is the same as the inherent closing time of the vacuum circuit breaker module, closing commands are issued to the AB phase closers at the same time, and the AB phase closers can initially turn on the transformer and load grid of the external photovoltaic power grid within 10us.

[0096] It should be noted that, since the C-phase closer has not yet been closed and turned on, the inrush current suppression module is in the preliminary closing stage, and the transformer of the external photovoltaic power grid and the load power grid are not yet fully turned on.

[0097] In some embodiments of step S430, based on the second closing time, the voltage point corresponding to the second closing time is compared with the most recent grid voltage peak point to determine whether the C phase voltage reaches the most recent grid voltage peak point.

[0098] If so, the C phase closer is driven to close, and the inrush current suppression module is in the re-step closing stage. The inrush current suppression module fully conducts the transformer and load grid of the external photovoltaic power grid, and closes before the vacuum circuit breaker module closes.

[0099] That is to say, when the C-phase voltage reaches the nearest 90°, a closing command is issued to the C-phase closer, and the C-phase closer can fully turn on the transformer and load grid of the external photovoltaic grid within 10us.

[0100] By closing the circuit breaker in steps, the inrush current suppression module is gradually put into operation before the vacuum circuit breaker module is activated, so as to reduce the impact current when the load is connected and avoid excessive impact on the power grid and load. In addition, gradual closing can reduce the overvoltage caused by the connection or disconnection of the capacitor bank, protecting electrical equipment. It helps to maintain the stable operation of the power grid and avoid system fluctuations caused by the sudden connection of large loads. For power grids with nonlinear loads, it can reduce the impact of harmonics on the power grid and adapt to different working conditions.

[0101] In some embodiments of another aspect of the present application, the closing control method further includes:

[0102] Step S600: When it is determined that the vacuum circuit breaker module is in the closed state, the A-phase closer, the B-phase closer and the C-phase closer in the three-phase closer are driven to open simultaneously, so that the inrush current suppression module is in the closed state.

[0103] In this embodiment, it is determined whether the vacuum breaker module has completed re-closing and is conducting the load and the external photovoltaic grid again, that is, whether it is in the closed state.

[0104] If so, an opening command is simultaneously issued to the A-phase closer, the B-phase closer, and the C-phase closer in the three-phase closer. The three-phase closer is opened, and the inrush current suppression module is in the off state until the next closing command is received.

[0105] The present application also provides an electronic device comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the above-mentioned closing control method when executing the computer program. The electronic device can be any smart terminal including a tablet computer, an in-vehicle computer, or the like.

[0106] It can be understood that the contents of the above method embodiments are applicable to the present device embodiments, the functions specifically implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0107] See also Figure 4 , Figure 4 The hardware structure of an electronic device according to another embodiment is shown. The electronic device includes:

[0108] The processor 401 may be implemented as a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of the present application.

[0109] The memory 402 can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 402 can store an operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program codes are stored in the memory 402 and are called by the processor 401 to execute the closing control method of the embodiments of this application.

[0110] Input / output interface 403, used to implement information input and output;

[0111] Communication interface 404, used to implement communication interaction between this device and other devices, which can be achieved through wired means (such as USB, network cable, etc.) or wireless means (such as mobile network, WiFi, Bluetooth, etc.);

[0112] Bus 405 , which transmits information between various components of the device (e.g., processor 401 , memory 402 , input / output interface 403 , and communication interface 404 );

[0113] The processor 401 , the memory 402 , the input / output interface 403 and the communication interface 404 are connected to each other in communication within the device via a bus 405 .

[0114] An embodiment of the present application further provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the above-mentioned closing control method is implemented.

[0115] It can be understood that the contents of the above method embodiments are all applicable to the present storage medium embodiment, the functions specifically implemented by the present storage medium embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0116] The memory, as a non-transient computer-readable storage medium, can be used to store non-transient software programs and non-transient computer executable programs. In addition, the memory may include a high-speed random access memory and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0117] The embodiments described in the embodiments of this application are intended to more clearly illustrate the technical solutions of the embodiments of this application and do not constitute a limitation on the technical solutions provided by the embodiments of this application. Those skilled in the art will appreciate that with the evolution of technology and the emergence of new application scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0118] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the present application, and may include more or fewer steps than shown in the figures, or a combination of certain steps, or different steps.

[0119] Those skilled in the art will appreciate that all or some of the steps in the methods, systems, and functional modules / units in the devices disclosed above may be implemented as software, firmware, hardware, or appropriate combinations thereof.

[0120] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0121] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and essence of the present invention should be within the scope of the present invention.

Claims

1. A photovoltaic loss reduction device, characterized in that: include: A vacuum circuit breaker module, the vacuum circuit breaker module is connected to the external photovoltaic grid and the load, and the vacuum circuit breaker module is used to control the on-off switching between the load and the external photovoltaic grid; an inrush current suppression module, the inrush current suppression module being connected in parallel with the vacuum circuit breaker module and configured to control the initial on / off of the load and the external photovoltaic power grid in steps before the vacuum circuit breaker module performs a conduction action; An overvoltage limiting module is connected in parallel with the inrush current suppression module and the vacuum circuit breaker module respectively, and the inrush current suppression module is used to limit the overvoltage generated by the vacuum circuit breaker module.

2. The photovoltaic loss reduction device according to claim 1, characterized in that: The inrush current suppression module includes: A three-phase closer, connected in parallel with the vacuum circuit breaker module, for regulating the initial on-off of the load and the external photovoltaic power grid; A phase controller is connected to the three-phase closer via an optical fiber, and is used to regulate the three-phase closer in steps before the vacuum circuit breaker module performs a conduction action.

3. The photovoltaic loss reduction device according to claim 1, characterized in that: The vacuum circuit breaker module comprises: an epoxy resin sleeve, wherein the inrush current suppression module and the overvoltage limiting module are sleeved in the epoxy resin sleeve; A vacuum interrupter, wherein the vacuum interrupter is sleeved in the epoxy resin sleeve, the inrush current suppression module is provided on one side of the vacuum interrupter, the overvoltage limiting module is provided on the other side of the vacuum interrupter, and both ends of the fracture of the vacuum interrupter are connected in parallel with the inrush current suppression module and the overvoltage limiting module respectively; Wherein, the vacuum interrupter and the overvoltage limiting module are integrally installed in the epoxy resin sleeve.

4. The photovoltaic loss reduction device according to claim 1, characterized in that: The overvoltage limiting module includes: A single-phase limiting unit, wherein each phase of the single-phase limiting unit is connected in parallel with the inrush current suppression module and the vacuum circuit breaker module, and each phase of the single-phase limiting unit includes a plurality of nonlinear resistors; Wherein, a plurality of the nonlinear resistors are connected in series to form a plurality of series sub-columns, and a plurality of the series sub-columns are connected in parallel to form the single-phase limiting unit.

5. A method for controlling the closing of a photovoltaic loss reduction device, characterized in that: The photovoltaic loss reduction device includes: a vacuum circuit breaker module and an inrush current suppression module; the method includes: Detect the current status of the vacuum circuit breaker module and the inrush current suppression module; When the vacuum circuit breaker module is in an open state and the inrush current suppression module is in an off state, determining whether an access instruction sent by an external photovoltaic power grid is received; When the access instruction is received, the inherent closing time of the vacuum circuit breaker module and the current grid voltage of the external photovoltaic grid are acquired, and a closing instruction is output to the vacuum circuit breaker module; According to the current grid voltage and the inherent closing time, before the vacuum circuit breaker module performs the conduction action, the inrush current suppression module is controlled to close in steps, so as to control the initial conduction between the load and the external photovoltaic grid in steps; According to the closing instruction, the vacuum circuit breaker module is controlled to switch from the open state to the closed state, and the load and the external photovoltaic power grid are connected again.

6. The closing control method according to claim 5, characterized in that: The inrush current suppression module includes a three-phase closer, and the step-by-step control of closing the inrush current suppression module includes: Determine, based on the current grid voltage, a first closing time from the current AB phase voltage to the nearest grid voltage peak point, and a second closing time from the current C phase voltage to the nearest grid voltage peak point in the three-phase closer; When the first closing time is the same as the inherent closing time, the A-phase closer and the B-phase closer in the three-phase closer are driven to close simultaneously to perform preliminary closing.

7. The closing control method according to claim 6, characterized in that: The step-by-step control of closing the inrush current suppression module includes: According to the second closing time, when the current C-phase voltage reaches the nearest grid voltage peak point, the C-phase closer in the three-phase closer is driven to close, so as to perform a further closing.

8. The closing control method according to claim 6, characterized in that: The method further comprises: When it is determined that the vacuum circuit breaker module is in the closed state, the A-phase closer, the B-phase closer and the C-phase closer in the three-phase closer are driven to open simultaneously, so that the inrush current suppression module is in the closed state.

9. An electronic device, characterized in that: The electronic device includes a memory and a processor, the memory stores a computer program, and the processor implements the method according to any one of claims 5 to 8 when executing the computer program.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 5 to 8 is implemented.

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