Control method and corresponding device of box-type transformer in distributed photovoltaic power station

Abstract

The present disclosure relates to a control method and a corresponding device for a box-type transformer in a distributed photovoltaic power station, wherein the control method comprises: determining voltage waveform data of a high-voltage busbar in a box-type transformer in a distributed photovoltaic power station and a voltage of a high-voltage side circuit breaker in a box-type transformer in a distributed photovoltaic power station at the moment of opening; determining a target phase angle according to the voltage waveform data and the voltage; and controlling the high-voltage side circuit breaker to be in a closed state according to the target phase angle, so as to avoid saturation of the iron core of the transformer each time the transformer supplies power, thereby reducing the current impact on the transformer of the box-type transformer at the moment of closing, and thereby avoiding the problem of damage to the transformer caused by the electric force accumulation effect caused by the current impact of long-term frequent closing (power supply once a day) of the box-type transformer in the distributed photovoltaic power station after adopting intelligent energy saving.

Description

Technical Field

[0001] The present disclosure relates to the field of electronic technology, and in particular to a control method and a corresponding device for a box-type transformer in a distributed photovoltaic power station. Background Art

[0002] The distributed photovoltaic power station box-type transformer mainly converts the DC power generated by the photovoltaic power generation system into AC power through a string inverter, and then connects it to the power grid system through the box-type transformer. When the distributed photovoltaic power station does not generate electricity at night, its transformer still has no-load loss during the non-generation period, which leads to energy waste. In related technologies, intelligent energy-saving methods are usually used to control whether the distributed photovoltaic power station box-type transformer is connected to the grid, thereby reducing energy waste. Summary of the invention

[0003] The purpose of the present disclosure is to provide a control method and corresponding device for a box-type transformer in a distributed photovoltaic power station to solve the technical problems existing in the related art.

[0004] In order to achieve the above object, the present disclosure provides a control method for a box-type transformer in a distributed photovoltaic power station, comprising: Determine the voltage waveform data of the medium and high voltage busbar of the distributed photovoltaic power station box-type transformer and the voltage of the medium and high voltage side circuit breaker of the distributed photovoltaic power station box-type transformer at the moment of opening; determining a target phase angle according to the voltage waveform data and the voltage; According to the target phase angle, the high-voltage side circuit breaker is controlled to be in a closed state.

[0005] Optionally, determining a target phase angle according to the voltage waveform data and the voltage includes: Determining a phase angle corresponding to the voltage according to the voltage waveform data; Determine the residual magnetism corresponding to the phase angle after the high-voltage side circuit breaker is opened, and determine the phase angle corresponding to the residual magnetism with opposite polarity and the transient magnetic flux as the target phase angle, wherein the transient magnetic flux is the magnetic flux generated by the high-voltage side circuit breaker at the moment of closing.

[0006] Optionally, determining a target phase angle according to the voltage waveform data and the voltage includes: The target phase angle is determined by a surge current suppressor according to the voltage waveform data and the voltage.

[0007] Optionally, the control method further includes: Determine the inrush current of the high-voltage side of the box-type transformer of the distributed photovoltaic power station at the moment of closing the high-voltage side circuit breaker; The target phase angle is adjusted according to the inrush current and the rated current of the transformer, so as to control the circuit breaker to be in a closed state according to the adjusted target phase angle.

[0008] Optionally, adjusting the target phase angle according to the inrush current and the rated current of the transformer includes: The target phase angle is adjusted according to the inrush current and the rated current of the transformer by a surge current suppressor.

[0009] Optionally, the step of determining voltage waveform data of a medium- and high-voltage busbar of a box-type transformer in a distributed photovoltaic power station includes: The voltage waveform data of the high-voltage bus in the box-type transformer of the distributed photovoltaic power station is collected through the first voltage transformer.

[0010] Optionally, the step of determining the voltage of the high-voltage side circuit breaker of the distributed photovoltaic power station box-type transformer at the moment of opening includes: The voltage of the high-voltage side circuit breaker in the distributed photovoltaic power station box at the moment of opening is collected through the second voltage transformer.

[0011] In a second aspect, the present disclosure further provides a control device for a box-type transformer of a distributed photovoltaic power station, comprising a first determination module, a second determination module and a control module; The first determination module is used to determine the voltage waveform data of the medium and high voltage busbar of the distributed photovoltaic power station box-type transformer and the voltage of the medium and high voltage side circuit breaker of the distributed photovoltaic power station box-type transformer at the moment of opening; The second determination module is used to determine a target phase angle according to the voltage waveform data and the voltage; The control module is used to control the high-voltage side circuit breaker to be in a closed state according to the target phase angle.

[0012] Optionally, the second determining module includes: A third determination module, used to determine the phase angle corresponding to the voltage according to the voltage waveform data; The fourth determination module is used to determine the residual magnetism corresponding to the phase angle after the circuit breaker is opened, and determine the phase angle corresponding to the residual magnetism with opposite polarity and the transient magnetic flux as the target phase angle, and the transient magnetic flux is the magnetic flux generated by the circuit breaker at the moment of closing.

[0013] Optionally, the second determining module is further used for: The target phase angle is determined by a surge current suppressor according to the voltage waveform data and the voltage.

[0014] Optionally, the control device further includes: A fifth determination module is used to determine the inrush current of the transformer of the distributed photovoltaic power station box-type transformer on the high-voltage side at the moment of closing the high-voltage side circuit breaker; An adjustment module is used to adjust the target phase angle according to the inrush current and the rated current of the transformer, so as to control the high-voltage side circuit breaker to be in a closed state according to the adjusted target phase angle.

[0015] Optionally, the adjustment module is further used for: The target phase angle is adjusted according to the inrush current and the rated current of the transformer by a surge current suppressor.

[0016] Optionally, the first determining module is further configured to: The voltage waveform data of the high-voltage bus in the box-type transformer of the distributed photovoltaic power station is collected through the first voltage transformer.

[0017] Optionally, the first determining module is further configured to: The voltage of the high-voltage side circuit breaker in the distributed photovoltaic power station box-type transformer at the moment of opening is collected through the second voltage transformer.

[0018] In a third aspect, the present disclosure further provides a distributed photovoltaic power station box-type transformer, comprising a first voltage transformer, a second voltage transformer and a surge suppressor; The input end of the first voltage transformer is connected to the high-voltage busbar of the box-type transformer of the distributed photovoltaic power station, the output end of the first voltage transformer is connected to the input end of the surge suppressor, the input end of the second voltage transformer is connected to the output end of the high-voltage side circuit breaker of the box-type transformer of the distributed photovoltaic power station, and the output end of the second voltage transformer is connected to the input end of the surge suppressor; The first voltage transformer is used to collect voltage waveform data of the high-voltage bus in the box-type transformer of the distributed photovoltaic power station; The second voltage transformer is used to collect the voltage of the high-voltage circuit breaker in the distributed photovoltaic power station box-type transformer at the moment of opening; The surge suppressor is used to determine a target phase angle according to the voltage waveform data and the voltage, and to control the circuit breaker to be in a closed state according to the target phase angle.

[0019] Optionally, the output end of the current transformer of the box-type transformer of the distributed photovoltaic power station is connected to the input end of the surge suppressor; The current transformer is used to collect the impact current of the high-voltage side of the box-type transformer of the distributed photovoltaic power station at the moment of closing the high-voltage side circuit breaker; The inrush current suppressor is further used to adjust the target phase angle according to the inrush current and the rated current of the transformer, so as to control the circuit breaker to be in a closed state according to the adjusted target phase angle.

[0020] In a fourth aspect, the present disclosure further provides a non-temporary computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any one of the methods provided in the first aspect of the present disclosure.

[0021] In a fifth aspect, the present disclosure further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps of any one of the methods provided in the first aspect of the present disclosure.

[0022] Through the above technical solution, the target phase angle is determined according to the voltage waveform data of the medium and high voltage busbars of the distributed photovoltaic power station box-type transformer and the voltage of the high-voltage side circuit breaker at the moment of opening; and the circuit breaker is controlled to be in the closed state according to the target phase angle. By controlling the circuit breaker to be in the closed state through the target phase angle, the current impact of the circuit breaker on the high-voltage side of the transformer at the moment of closing can be reduced, thereby avoiding the electrodynamic accumulation effect caused by the current impact of long-term frequent closing (power transmission once a day), which will cause problems such as transformer insulation reduction and oil leakage, and at the same time, it can avoid damage to the box-type transformer and extend its service life.

[0023] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings: Figure 1 It is a schematic diagram of a box-type transformer in a distributed photovoltaic power station in the related technology.

[0025] Figure 2 It is a schematic diagram of the magnetic flux relationship of a box-type transformer in a distributed photovoltaic power station in the related technology.

[0026] Figure 3 It is a schematic diagram of transformer flux curve corresponding to closing and opening of circuit breaker in related technology.

[0027] Figure 4 The figure is a schematic diagram showing a control method of a box-type transformer in a distributed photovoltaic power station according to an exemplary embodiment of the present disclosure.

[0028] Figure 5 The figure is a schematic diagram showing a box-type transformer of a distributed photovoltaic power station according to an exemplary embodiment of the present disclosure.

[0029] Figure 6 is a schematic diagram showing voltage waveform data and a voltage waveform of a circuit breaker according to an exemplary embodiment of the present disclosure.

[0030] Figure 7 The figure is a schematic diagram showing a control device of a box-type transformer of a distributed photovoltaic power station according to an exemplary embodiment of the present disclosure.

[0031] Description of Reference Numerals 1. High-voltage busbar; 2. High-voltage side circuit breaker; 3. Transformer; 4. First voltage transformer; 5. Current transformer; 6. Second voltage transformer; 7. Surge suppressor; 700. Control device for box-type transformer of distributed photovoltaic power station; 701. First determination module; 702. Second determination module; 703. Control module. DETAILED DESCRIPTION

[0032] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0033] It should be noted that all actions of acquiring signals, information or data in the present disclosure are carried out in compliance with the relevant data protection laws and policies of the country where the device is located and with the authorization given by the owner of the corresponding device.

[0034] In the related technology, the installed capacity of distributed photovoltaic power generation is very large. The capacity of each photovoltaic box-type transformer in a distributed photovoltaic power station is generally 1000KVA~3150KVA, and there are many installed units and they are widely distributed. In order to save the no-load power energy loss of the transformer in the box-type transformer of the distributed photovoltaic power station during the period of no power generation at night, it is usually achieved through intelligent energy-saving methods, that is, automatically cutting off the power at night, and automatically connecting the distributed photovoltaic power station to the grid through the box-type transformer when the light amplitude reaches the requirement the next day.

[0035] like Figure 1 and Figure 2 As shown, in this Figure 1 and Figure 2 In the distributed photovoltaic power station, the magnetic flux of transformer 3 before closing is residual magnetic At the moment of closing the switch and supplying power, a voltage is applied, which will generate a steady-state magnetic flux at transformer 3. According to the law of conservation of magnetic flux, a transient induced magnetic flux with the same magnitude and opposite direction to the steady-state magnetic flux can be generated. The transient induced magnetic flux and the residual magnetism of transformer 3 synthesize the bias magnetic field. ,Right now = + . Bias The transformer 3 will decay slowly over time. With steady-state flux The total magnetic flux When the saturation flux is exceeded, the transformer winding reactance drops sharply, and the transformer power transmission will generate a large excitation inrush current. The excitation inrush current is a large current generated by the core magnetization saturation of the transformer 3 at the moment of closing.

[0036] The total magnetic flux can be expressed by the following calculation formula.

[0037]

[0038] in, is related to the winding voltage The corresponding steady-state flux, It is the residual magnetism left by transformer 3 when it was powered off last time. Its polarity and value are determined by the position of the hysteresis loop working point of the magnetic circuit at the moment when the high-voltage side circuit breaker 2 is opened. It is based on the law of conservation of magnetic flux and is used to resist the transient induced magnetic flux generated by the sudden change of magnetic flux at the moment of power-on. , bias magnet The time constant attenuation. is the phase angle, is a constant, For time.

[0039] like Figure 3 As shown, it includes the steady-state flux curve of the primary winding voltage, the 90° lagging voltage, and the transient induced flux curve corresponding to the steady-state flux curve at the same time. The corresponding steady-state flux is positive when the power is cut off at the moment of opening the switch 1, so the residual magnetic polarity of the transformer 3 of the distributed photovoltaic power station box-type transformer is positive. When the power is supplied at the closing point 1, the steady-state flux is positive, and the corresponding transient induced flux is negative on the curve, and the bias magnetism synthesized by the positive residual magnetism and the transient induced flux of the negative line is Φp1. That is, when the transformer 3 supplies power, the steady-state flux starts to be established from the residual magnetism point M and shifts in the direction of the bias polarity (below), and the curve Φ1 can be a curve synthesized by the steady-state flux and the bias magnetism. During the flux establishment process, the total flux Φ1 does not reach the saturation flux value, so no large inrush current is generated. Similarly, the transient induced flux polarity at point N corresponding to closing 2 is negative in the same direction as the residual magnetism, and the synthetic bias Φp2 increases in a negative direction. During the flux establishment process, the steady-state flux and the bias offset are superimposed on the total flux Φ2 curve. A large excitation surge current will be generated in the interval exceeding the saturation flux in the negative direction.

[0040] The magnitude of this excitation current (inrush current) depends on the phase angle of the opening moment and the closing moment of the high-voltage side circuit breaker 2. If the timing of opening and closing is not chosen properly, the transformer core will inevitably be saturated, and the inrush current generated can reach up to 3 to 5 times the rated current. However, the inventors have found that if the transformer is subjected to current shock by frequent closing (power supply once a day) for a long time, the accumulation effect of its electromotive force will cause relative displacement of the transformer winding or internal structure, which may cause the insulation of the transformer 3 to decrease, oil leakage of the oil-immersed transformer, and reduce the service life of the transformer.

[0041] In view of this, the present disclosure provides a control method and corresponding device for a box-type transformer in a distributed photovoltaic power station to solve the technical problems existing in the related art.

[0042] like Figure 4 As shown, Figure 4 is a schematic diagram showing a control method of a distributed photovoltaic power station box-type transformer according to an exemplary embodiment of the present disclosure, with reference to Figure 4 ,include: S401: Determine the voltage waveform data of the medium and high voltage busbar of the distributed photovoltaic power station box-type transformer and the voltage of the medium and high voltage side circuit breaker of the distributed photovoltaic power station box-type transformer at the moment of opening; S402: determining a target phase angle according to the voltage waveform data and the voltage; S403: According to the target phase angle, control the high-voltage side circuit breaker 2 to be in a closed state.

[0043] Through the above technical solution, the target phase angle is determined according to the voltage waveform data of the high-voltage bus 1 of the distributed photovoltaic power station box-type transformer and the voltage of the high-voltage side circuit breaker 2 at the moment of opening; and according to the target phase angle, the high-voltage side circuit breaker 2 is controlled to be in the closed state. By controlling the high-voltage side circuit breaker 2 to be in the closed state through the target phase angle, the current impact of the high-voltage side circuit breaker 2 on the high-voltage side of the transformer 3 at the moment of closing can be reduced, thereby reducing the accumulation effect of the electric force generated by the frequent closing current impact of the distributed photovoltaic power station box-type transformer, causing insulation damage, oil leakage and other problems of the transformer 3, and at the same time, the service life of the transformer 3 can be extended.

[0044] In order to enable those skilled in the art to better understand the control method of the box-type transformer of the distributed photovoltaic power station provided by the present disclosure, the above steps are described in detail with examples below.

[0045] For example, the high-voltage bus 1 in the box-type transformer of the distributed photovoltaic power station can be a conductor of the power equipment in the box-type transformer. In this embodiment, the voltage waveform data of the high-voltage bus 1 can be used as a reference voltage to judge the phase angle corresponding to the voltage of the high-voltage side circuit breaker 2 at the moment of opening, which can be used to control the closing timing of the high-voltage side circuit breaker 2 in the subsequent process.

[0046] In a possible manner, the step of determining the voltage waveform data of the medium- and high-voltage busbar 1 of the distributed photovoltaic power station box-type transformer includes: The voltage waveform data of the high-voltage bus 1 in the box-type transformer of the distributed photovoltaic power station is collected through the first voltage transformer 4.

[0047] It should be understood that the first voltage transformer 4 can be used to reduce the high voltage on the high-voltage bus 1 to safe and measurable voltage data. Therefore, the voltage waveform data of the high-voltage bus 1 of the box-type transformer of the distributed photovoltaic power station can be collected through the first voltage transformer 4, and this is not specifically limited in the embodiment of the present disclosure.

[0048] In a possible manner, the method of determining the voltage of the high-voltage side circuit breaker 2 of the distributed photovoltaic power station box-type transformer at the moment of opening includes: The voltage of the high-voltage side circuit breaker 2 in the distributed photovoltaic power station box-type transformer at the moment of opening is collected through the second voltage transformer 6.

[0049] It should be understood that the second voltage transformer 6 can be used to reduce the high voltage on the high-voltage side circuit breaker 2 to a safe and measurable voltage data. In this embodiment, the voltage of the high-voltage side circuit breaker 2 of the distributed photovoltaic power station box-type transformer at the moment of opening can be collected by the second voltage transformer 6.

[0050] For example, during the normal operation of the box-type transformer in a distributed photovoltaic power station, the waveform data of the voltage transmitted to the high-voltage side circuit breaker 2 through the high-voltage bus 1 is the same as the voltage waveform data on the high-voltage bus 1. Therefore, after determining the voltage waveform data and the voltage, the voltage waveform data on the high-voltage bus 1 can be used as a reference voltage or a reference voltage. According to the voltage waveform data, the phase angle corresponding to the voltage can be obtained, and the target phase angle can be determined according to the phase angle. Afterwards, the high-voltage side circuit breaker 2 can be controlled to close according to the target phase angle. When the high-voltage side circuit breaker 2 is controlled to close according to the target phase angle, the current impact of the high-voltage side circuit breaker 2 on the high-voltage side of the transformer 3 at the moment of closing can be reduced, thereby reducing the accumulation effect of the electric force caused by the long-term frequent closing current impact of the coil winding of the transformer 3 in the box-type transformer of the distributed photovoltaic power station, causing insulation damage, oil leakage and other problems of the transformer 3, and at the same time, the service life of the transformer 3 can be extended. In a possible manner, the target phase angle is determined according to the voltage waveform data and the voltage, including: Determining a phase angle corresponding to the voltage according to the voltage waveform data; Determine the residual magnetism corresponding to the phase angle after the high-voltage side circuit breaker 2 is opened, and determine the phase angle corresponding to the residual magnetism with opposite polarity and the transient magnetic flux as the target phase angle, and the transient magnetic flux is the magnetic flux generated by the high-voltage side circuit breaker 2 at the moment of closing. It should be understood that when the voltage waveform data is used as a reference voltage or a reference voltage, the corresponding voltage waveform data can be a sine wave waveform data, wherein each voltage corresponds to a phase angle on the voltage waveform data. And the voltage waveform data can generate a corresponding steady-state magnetic flux, and when the high-voltage side circuit breaker 2 is closed, a transient induced magnetic flux equal in magnitude to the steady-state magnetic flux and opposite in direction can be generated at the moment of closing.

[0051] When the high-voltage side circuit breaker 2 is opened, the voltage of the opening can be detected, and the phase angle corresponding to the voltage can be determined according to the voltage waveform data. When the high-voltage side circuit breaker 2 is opened, residual magnetism can be generated at the point of the steady-state magnetic flux corresponding to the phase angle. The residual magnetism can be the magnetic flux remaining in the magnetic material when the transformer 3 is opened.

[0052] When the residual magnetism is positive and the transient induced flux is positive, the residual magnetism and the transient induced flux are combined into a positive bias magnetism with an increased amplitude, and the total flux curve shifts upward. The magnetic circuit is more easily saturated, and the amplitude of the excitation surge current will be larger. When the residual magnetism is positive and the transient induced flux is controlled to be negative, the bias magnetism synthesized by the residual magnetism and the transient induced flux will decrease, or even be 0, then the amplitude of the total flux curve shift will decrease, or even not shift, the chance of the magnetic circuit tending to saturation decreases, and the excitation surge current will be very small. Therefore, the range of the phase angle corresponding to the total flux synthesized by the residual magnetism, transient induced flux, and steady-state flux can be used as the target phase angle.

[0053] Then, the closing state of the high-voltage side circuit breaker 2 can be controlled according to the target phase angle, which can reduce the current impact of the high-voltage side circuit breaker 2 on the high-voltage side of the transformer 3 at the moment of closing, and thus reduce the accumulation effect of the electric force caused by the frequent closing current impact of the distributed photovoltaic power station box-type transformer for a long time, which may cause insulation damage, oil leakage and other problems of the transformer 3, and at the same time, the service life of the transformer 3 can be extended. In a possible manner, the target phase angle is determined according to the voltage waveform data and the voltage, including: The target phase angle is determined by the surge suppressor 7 according to the voltage waveform data and the voltage.

[0054] It should be understood that the surge suppressor 7 may be a device or instrument for suppressing excitation surge current. When determining the target phase angle according to the voltage waveform data and the voltage, the target phase angle may also be determined by the surge suppressor 7, and the embodiment of the present disclosure does not specifically limit this.

[0055] In a possible manner, the control method further includes: Determine the inrush current of the box-type transformer 3 of the distributed photovoltaic power station on the high-voltage side at the moment of closing the high-voltage side circuit breaker 2; The target phase angle is adjusted according to the inrush current and the rated current of the transformer 3 , so as to control the high-voltage side circuit breaker 2 to be in a closed state according to the adjusted target phase angle.

[0056] It should be understood that when the high-voltage side circuit breaker 2 is controlled to be in the closed state according to the target phase angle, the inrush current of the transformer 3 of the distributed photovoltaic power station box-type transformer on the high-voltage side can be monitored in real time. Then the target phase angle can be adjusted according to the inrush current and the rated current of the transformer 3. When the inrush current is less than the rated current, it can represent that the current generated by controlling the high-voltage side circuit breaker 2 to be closed according to the target phase angle at this time will not have any effect on the transformer 3, and then the inrush current impact can be buffered, the damage to the transformer 3 can be reduced, and the service life of the transformer 3 can be extended.

[0057] When the inrush current is greater than the rated current, it means that the inrush current generated by the closing of the circuit breaker at this time will cause certain damage to the transformer 3, and may cause oil leakage and other problems in the transformer 3. It is necessary to properly adjust the target phase angle, and control the closing state of the high-voltage side circuit breaker 2 according to the adjusted target phase angle. In this way, the inrush current generated by the high-voltage side circuit breaker 2 at the moment of closing is less than the rated current of the transformer 3, thereby protecting the transformer 3 from damage.

[0058] By adjusting the target phase angle of the high-voltage side circuit breaker 2 in the closed state according to the impact current and the rated current, the impact current of the high-voltage side circuit breaker 2 on the high-voltage side of the transformer 3 at the moment of closing can be reduced, thereby reducing the damage to the coil winding of the transformer 3 of the distributed photovoltaic power station box-type transformer, the oil leakage of the transformer 3 and other problems, and at the same time, the service life of the transformer 3 can be extended.

[0059] In a possible manner, adjusting the target phase angle according to the inrush current and the rated current of the transformer 3 includes: The target phase angle is appropriately adjusted according to the inrush current and the rated current of the transformer 3 by the surge current suppressor 7 .

[0060] It should be understood that when the target phase angle is adjusted according to the inrush current and the rated current of the transformer 3 , the adjustment can be performed through the surge suppressor 7 , and the embodiments of the present disclosure do not specifically limit this.

[0061] The target phase angle is determined by the voltage waveform data of the high-voltage bus 1 and the voltage of the high-voltage side circuit breaker 2 at the moment of opening. The closing state of the high-voltage side circuit breaker 2 is controlled according to the target phase angle, which can avoid the accumulation effect of the electric force caused by the frequent closing current impact of the distributed photovoltaic power station box-type transformer for a long time, causing insulation damage and oil leakage of the transformer 3, thereby extending the service life of the box-type transformer 3. At the same time, these distributed photovoltaic power station box-type transformers can be cut off at night to achieve intelligent energy saving, which has been well promoted and applied.

[0062] Based on the same concept, this embodiment also discloses a distributed photovoltaic power station box-type transformer, referring to Figure 5 , Figure 5 is a schematic diagram showing a box-type transformer of a distributed photovoltaic power station according to an exemplary embodiment of the present disclosure, such as Figure 5 As shown, it includes a first voltage transformer, a second voltage transformer and a surge suppressor 7; The input end of the first voltage transformer is connected to the medium and high voltage bus 1 of the distributed photovoltaic power station box-type transformer, the output end of the first voltage transformer is connected to the input end of the surge suppressor 7, the input end of the second voltage transformer is connected to the output end of the medium and high voltage side circuit breaker 2 of the distributed photovoltaic power station box-type transformer, and the output end of the second voltage transformer is connected to the input end of the surge suppressor 7; The first voltage transformer is used to collect voltage waveform data of the medium and high voltage bus 1 of the box-type transformer of the distributed photovoltaic power station; The second voltage transformer is used to collect the voltage of the high-voltage side circuit breaker 2 of the distributed photovoltaic power station box-type transformer at the moment of opening; The surge suppressor 7 is used to determine a target phase angle according to the voltage waveform data and the voltage, and to control the high-voltage side circuit breaker 2 to be in a closed state according to the target phase angle.

[0063] For example, in the distributed photovoltaic power station box-type transformer, the voltage waveform data collected from the high-voltage bus 1 can be transmitted to the surge suppressor 7 through the first voltage transformer. The voltage at the moment of opening collected from the high-voltage side circuit breaker 2 can be transmitted to the surge suppressor 7 through the second voltage transformer. Figure 6 As shown, Figure 6 TV1 can be the voltage waveform data collected by the first voltage transformer. Figure 6 TV2 may be the voltage waveform data corresponding to the high-voltage side circuit breaker 2 of the distributed photovoltaic power station box-type transformer when it is opened and closed.

[0064] The surge suppressor 7 can determine the target phase angle according to the transmitted voltage waveform data and voltage, and control the closing timing of the high-voltage side circuit breaker 2 according to the target phase angle, thereby avoiding saturation of the core of the transformer 3 and reducing the impact current on the transformer 3.

[0065] In a possible manner, the output end of the current transformer of the box-type transformer of the distributed photovoltaic power station is connected to the input end of the surge suppressor 7; The current transformer is used to collect the impact current of the transformer 3 of the distributed photovoltaic power station box-type transformer on the high-voltage side at the moment of closing the high-voltage side circuit breaker 2; The surge current suppressor 7 is further used to adjust the target phase angle according to the impact current and the rated current of the transformer 3 .

[0066] It should be understood that the box-type transformer of the distributed photovoltaic power station also includes a current transformer, which can collect the impact current of the transformer 3 on the high-voltage side of the high-voltage side circuit breaker 2 at the moment of closing, and transmit the impact current to the surge suppressor 7 for processing. After receiving the impact current, the surge suppressor 7 compares the impact current with the rated current of the transformer 3, and adjusts the target phase angle appropriately to control the high-voltage side circuit breaker 2 to close at a more reasonable time according to the adjusted target phase angle.

[0067] Based on the same concept, this embodiment also provides a control device 700 for a distributed photovoltaic power station box-type transformer, referring to Figure 7 , Figure 7 FIG. 7 is a schematic diagram showing a control device 700 for a box-type transformer of a distributed photovoltaic power station according to an exemplary embodiment of the present disclosure. Figure 7 As shown, it includes a first determination module 701, a second determination module 702 and a control module 703; The first determination module 701 is used to determine the voltage waveform data of the medium and high voltage busbar of the distributed photovoltaic power station box-type transformer and the voltage of the medium and high voltage side circuit breaker of the distributed photovoltaic power station box-type transformer at the moment of opening; The second determination module 702 is used to determine a target phase angle according to the voltage waveform data and the voltage; The control module 703 is used to control the high-voltage side circuit breaker to be in a closed state according to the target phase angle.

[0068] Optionally, the second determining module 702 includes: A third determination module, used to determine the phase angle corresponding to the voltage according to the voltage waveform data; The fourth determination module is used to determine the residual magnetism corresponding to the phase angle after the high-voltage side circuit breaker 2 is opened, and determine the phase angle corresponding to the residual magnetism with opposite polarity and the transient magnetic flux as the target phase angle, and the transient magnetic flux is the magnetic flux generated by the high-voltage side circuit breaker 2 at the moment of closing.

[0069] Optionally, the second determining module 702 is further configured to: The target phase angle is determined by the surge suppressor 7 according to the voltage waveform data and the voltage.

[0070] Optionally, the control device 700 further includes: A fifth determination module is used to determine the inrush current of the transformer 3 of the distributed photovoltaic power station box-type transformer on the high-voltage side at the moment of closing the high-voltage side circuit breaker 2; The adjustment module is used to appropriately adjust the target phase angle according to the inrush current and the rated current of the transformer 3 .

[0071] Optionally, the adjustment module is further used for: The target phase angle is adjusted according to the inrush current and the rated current of the transformer 3 by the surge current suppressor 7 .

[0072] Optionally, the first determining module 701 is further configured to: The voltage waveform data of the high-voltage bus 1 in the box-type transformer of the distributed photovoltaic power station is collected through the first voltage transformer 4.

[0073] Optionally, the first determining module 701 is further configured to: The voltage of the high-voltage side circuit breaker 2 in the distributed photovoltaic power station box-type transformer at the moment of opening is collected through the second voltage transformer 6.

[0074] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0075] Based on the same concept, the present embodiment also discloses a non-temporary computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the control method of the box-type transformer of the distributed photovoltaic power station disclosed in the present embodiment are implemented.

[0076] In another exemplary embodiment, a computer program product is also provided, which includes a computer program that can be executed by a programmable device, and has a code portion for executing the above-mentioned control method of the box-type transformer of the distributed photovoltaic power station when executed by the programmable device.

[0077] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0078] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0079] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A control method for a box-type transformer in a distributed photovoltaic power station, characterized in that: include: Determine the voltage waveform data of the medium and high voltage busbar of the distributed photovoltaic power station box-type transformer and the voltage of the medium and high voltage side circuit breaker of the distributed photovoltaic power station box-type transformer at the moment of opening; determining a target phase angle according to the voltage waveform data and the voltage; According to the target phase angle, the high-voltage side circuit breaker is controlled to be in a closed state.

2. The control method of the distributed photovoltaic power station box-type transformer according to claim 1 is characterized in that: The step of determining a target phase angle according to the voltage waveform data and the voltage comprises: Determining a phase angle corresponding to the voltage according to the voltage waveform data; Determine the residual magnetism corresponding to the phase angle after the high-voltage side circuit breaker is opened, and determine the phase angle corresponding to the residual magnetism with opposite polarity and the transient magnetic flux as the target phase angle, wherein the transient magnetic flux is the magnetic flux generated by the high-voltage side circuit breaker at the moment of closing.

3. The control method of the distributed photovoltaic power station box-type transformer according to claim 1 is characterized in that: The step of determining a target phase angle according to the voltage waveform data and the voltage comprises: The target phase angle is determined by a surge current suppressor according to the voltage waveform data and the voltage.

4. The control method of the distributed photovoltaic power station box-type transformer according to claim 1 is characterized in that: The control method further comprises: Determine the inrush current of the high-voltage side of the box-type transformer of the distributed photovoltaic power station at the moment of closing the high-voltage side circuit breaker; The target phase angle is adjusted according to the inrush current and the rated current of the transformer, so as to control the high-voltage side circuit breaker to be in a closed state according to the adjusted target phase angle.

5. The control method of the distributed photovoltaic power station box-type transformer according to claim 4 is characterized in that: The adjusting the target phase angle according to the inrush current and the rated current of the transformer comprises: The target phase angle is adjusted according to the inrush current and the rated current of the transformer by a surge current suppressor.

6. The control method of the box-type transformer of a distributed photovoltaic power station according to any one of claims 1 to 5, characterized in that: The method of determining the voltage waveform data of the medium and high voltage busbars of the box-type transformers in the distributed photovoltaic power station includes: The voltage waveform data of the high-voltage bus in the box-type transformer of the distributed photovoltaic power station is collected through the first voltage transformer.

7. The control method of the box-type transformer of a distributed photovoltaic power station according to any one of claims 1 to 5, characterized in that: The method of determining the voltage of the high-voltage side circuit breaker of the distributed photovoltaic power station box-type transformer at the moment of opening includes: The voltage of the high-voltage side circuit breaker in the distributed photovoltaic power station box at the moment of opening is collected through the second voltage transformer.

8. A control device for a box-type transformer in a distributed photovoltaic power station, characterized in that: It includes a first determining module, a second determining module and a control module; The first determination module is used to determine the voltage waveform data of the medium and high voltage busbar of the distributed photovoltaic power station box-type transformer and the voltage of the medium and high voltage side circuit breaker of the distributed photovoltaic power station box-type transformer at the moment of opening; The second determination module is used to determine a target phase angle according to the voltage waveform data and the voltage; The control module is used to control the high-voltage side circuit breaker to be in a closed state according to the target phase angle.

9. The control device for the box-type transformer of a distributed photovoltaic power station according to claim 8 is characterized in that: The second determining module comprises: A third determination module, used to determine the phase angle corresponding to the voltage according to the voltage waveform data; The fourth determination module is used to determine the residual magnetism corresponding to the phase angle after the circuit breaker is opened, and determine the phase angle corresponding to the residual magnetism with opposite polarity and the transient magnetic flux as the target phase angle, and the transient magnetic flux is the magnetic flux generated by the circuit breaker at the moment of closing.

10. The control device for the box-type transformer of a distributed photovoltaic power station according to claim 8, characterized in that: The control device also includes: A fifth determination module is used to determine the inrush current of the transformer of the distributed photovoltaic power station box-type transformer on the high-voltage side at the moment of closing the high-voltage side circuit breaker; An adjustment module is used to adjust the target phase angle according to the inrush current and the rated current of the transformer, so as to control the high-voltage side circuit breaker to be in a closed state according to the adjusted target phase angle.

11. A distributed photovoltaic power station box-type transformer, characterized in that: It includes a first voltage transformer, a second voltage transformer and a surge suppressor; The input end of the first voltage transformer is connected to the high-voltage busbar of the distributed photovoltaic power station box-type transformer, the output end of the first voltage transformer is connected to the input end of the surge suppressor, the input end of the second voltage transformer is connected to the output end of the high-voltage side circuit breaker in the distributed photovoltaic power station box-type transformer, and the output end of the second voltage transformer is connected to the input end of the surge suppressor; The first voltage transformer is used to collect voltage waveform data of the high-voltage bus in the box-type transformer of the distributed photovoltaic power station; The second voltage transformer is used to collect the voltage of the high-voltage circuit breaker in the distributed photovoltaic power station box-type transformer at the moment of opening; The surge suppressor is used to determine a target phase angle according to the voltage waveform data and the voltage, and to control the circuit breaker to be in a closed state according to the target phase angle.

12. The distributed photovoltaic power station box-type transformer according to claim 11, characterized in that: The output end of the current transformer of the box-type transformer of the distributed photovoltaic power station is connected to the input end of the surge suppressor; The current transformer is used to collect the impact current of the high-voltage side of the box-type transformer of the distributed photovoltaic power station at the moment of closing the high-voltage side circuit breaker; The inrush current suppressor is further used to adjust the target phase angle according to the inrush current and the rated current of the transformer, so as to control the circuit breaker to be in a closed state according to the adjusted target phase angle.

13. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

14. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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