A reactive power compensation method, system, control device, and storage medium

Abstract

The present application provides a reactive power compensation method, system, control device and storage medium, which relate to the field of power technology and include: obtaining a synchronous rotation angle; obtaining the current three-phase voltage and the current three-phase current, and calculating based on the phase-locked loop algorithm according to the synchronous rotation angle, the current three-phase voltage and the current three-phase current to obtain the current reactive power; and obtaining the current capacitor voltage, detecting a potential point on the grid side with a voltage value equal to the current capacitor voltage to obtain an equipotential point, and determining the current equipotential point according to the time interval between two adjacent equipotential points; when the current reactive power is greater than or equal to the current capacitor capacity on the capacitor side, recording and based on the current time, the mechanical delay time and the current equipotential point, obtaining a target action time and a target equipotential point according to a determination strategy; outputting a relay control signal after delaying the target action time, and putting the capacitor into the grid side at the target equipotential point for reactive power compensation to provide a fast reactive power compensation response.

Description

Technical Field

[0001] The present application relates to the technical field of electric power, and in particular, to a reactive power compensation method, system, control device, and storage medium. Background Art

[0002] In the scenario of the power grid outputting alternating current, it is usually necessary to perform reactive power compensation on the power grid. The full name of reactive power compensation is reactive power compensation, which plays a role in improving the power factor of the power grid in the power supply system, reducing the losses of the power supply transformer and transmission lines, improving the power supply efficiency, and improving the power supply environment. Therefore, the reactive power compensation device is in an indispensable and important position in the power supply system.

[0003] Reactive power compensation is usually achieved by injecting capacitors into the power grid. The voltage on the power grid side is a sine wave signal with a frequency of 50HZ, that is, 20 milliseconds (ms). The traditional reactive power compensation method is as follows: within one cycle (i.e., 20 ms), the zero-crossing points of the voltage and the current are detected, and then the phase difference between the zero-crossing points of the voltage and the current is calculated. The reactive power is calculated based on the phase difference. When there is a need to inject a capacitor into the power grid, wait for the internal charge of the capacitor to be discharged completely, that is, when the charge is zero, detect the zero-crossing point of the voltage on the power grid side, and inject the capacitor into the power grid side at the zero-crossing point of the voltage on the power grid side.

[0004] In the traditional reactive power compensation method, the calculation process of reactive power and the response of the capacitor injection / removal operation are relatively slow, resulting in a long operation time for the traditional reactive power compensation method and unable to form a fast reactive power compensation response. Summary of the Invention

[0005] The present application provides a reactive power compensation method, system, control device, and storage medium to provide a fast reactive power compensation response.

[0006] In a first aspect, the present application provides a reactive power compensation method, which includes:

[0007] Obtain a synchronous rotation angle;

[0008] Obtain the current three-phase voltage and the current three-phase current on the power grid side, and calculate based on the phase-locked loop algorithm according to the synchronous rotation angle, the current three-phase voltage, and the current three-phase current to obtain the current reactive power; and obtain the current capacitor voltage on the capacitor side, detect the equipotential point on the power grid side with the same voltage value as the current capacitor voltage to obtain the equipotential point, and determine the current equipotential point according to the time interval between two adjacent equipotential points, where the equipotential point includes a rising-edge equipotential point and a falling-edge equipotential point;

[0009] When the current reactive power is greater than or equal to the current capacitance of the capacitor side, record the current time, and based on the determination strategy, obtain the target action time and the target equipotential point according to the current time, the mechanical delay time, and the current equipotential point;

[0010] Starting from the current time, delay the target action time and then output a relay control signal, so that the capacitor on the capacitor side is connected to the grid side at the target equipotential point to perform reactive power compensation on the grid side.

[0011] In a possible design, the obtaining of the synchronous rotation angle includes:

[0012] Obtain the three-phase voltage of the grid side in real time;

[0013] Use a phase-locked loop for phase locking to obtain the synchronous rotation angle.

[0014] In a possible design, based on the phase-locked loop algorithm, calculate the current reactive power according to the synchronous rotation angle, the current three-phase voltage, and the current three-phase current, including:

[0015] Perform Clarke coordinate transformation on the current three-phase voltage to obtain a first voltage coordinate component and a second voltage coordinate component;

[0016] Perform Clarke coordinate transformation on the current three-phase current to obtain a first current coordinate component and a second current coordinate component;

[0017] Use the synchronous rotation angle to perform Park coordinate transformation on the first voltage coordinate component and the second voltage coordinate component to obtain a third voltage coordinate component and a fourth voltage coordinate component;

[0018] Use the synchronous rotation angle to perform Park coordinate transformation on the first current coordinate component and the second current coordinate component to obtain a third current coordinate component and a fourth current coordinate component;

[0019] According to the formula , calculate to obtain the current reactive power, where Q is the current reactive power, is the third voltage coordinate component, is the fourth voltage coordinate component, is the third current coordinate component, is the fourth current coordinate component.

[0020] In a possible design, to obtain the current capacitor voltage on the capacitor side and detect the equipotential point equal to the voltage value of the current capacitor voltage on the grid side, including:

[0021] Obtain the current capacitor voltage on the capacitor side;

[0022] At the potential point where the rising edge of the sine wave on the grid side is equal to the voltage value of the current capacitor voltage, obtain the rising-edge equipotential point;

[0023] At the potential point where the falling edge of the sine wave on the grid side is equal to the voltage value of the current capacitor voltage, obtain the falling-edge equipotential point.

[0024] In a possible design, the determining the current equipotential point according to the time interval between two adjacent equipotential points includes:

[0025] Obtain two adjacent rising-edge equipotential points to get a first rising-edge equipotential point and a second rising-edge equipotential point;

[0026] Calculate the time interval between the first rising-edge equipotential point and the second rising-edge equipotential point to get a first time interval;

[0027] Obtain two adjacent falling-edge equipotential points to get a first falling-edge equipotential point and a second falling-edge equipotential point;

[0028] Calculate the time interval between the first falling-edge equipotential point and the second falling-edge equipotential point to get a second time interval;

[0029] If both the first time interval and the second time interval are equal to the interval threshold, determine that the equipotential point is in a stable state, and return to execute the step: Obtain two adjacent rising-edge equipotential points to get a first rising-edge equipotential point and a second rising-edge equipotential point. Each time returning to execute the step: Obtain two adjacent rising-edge equipotential points to get a first rising-edge equipotential point and a second rising-edge equipotential point, update the second rising-edge equipotential point or the second falling-edge equipotential point of the current detection period to the first rising-edge equipotential point or the first falling-edge equipotential point of the next detection period;

[0030] Determine the first rising-edge equipotential point or the first falling-edge equipotential point as the current equipotential point.

[0031] In a possible design, the obtaining the target action time and the target equipotential point based on the determination strategy according to the current moment, the mechanical delay time, and the current equipotential point includes:

[0032] Calculate the time difference between the first rising-edge equipotential point and the current moment to get a rising-edge interval;

[0033] Calculate the time difference between the first falling-edge equipotential point and the current moment to get a falling-edge interval;

[0034] Calculate the sum of the rising edge interval and the mechanical delay time to obtain the rising edge time sum;

[0035] Calculate the sum of the falling edge interval and the mechanical delay time to obtain the falling edge time sum;

[0036] Based on the determination strategy, obtain the target action time and the target equipotential point according to the rising edge time sum and the falling edge time sum.

[0037] In a possible design, the step of obtaining the target action time and the target equipotential point based on the determination strategy according to the rising edge time sum and the falling edge time sum includes:

[0038] Under the condition that the rising edge time sum is less than or equal to 20 milliseconds and the falling edge time sum is less than or equal to 20 milliseconds:

[0039] If the rising edge time sum is greater than or equal to the falling edge time sum, the target equipotential point is the next rising edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the rising edge time sum;

[0040] If the rising edge time sum is less than the falling edge time sum, the target equipotential point is the next falling edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the falling edge time sum;

[0041] Under the condition that the rising edge time sum is less than or equal to 20 milliseconds and the falling edge time sum is greater than 20 milliseconds: then the target equipotential point is the next rising edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the rising edge time sum;

[0042] Under the condition that the rising edge time sum is greater than 20 milliseconds and the falling edge time sum is less than or equal to 20 milliseconds: then the target equipotential point is the next falling edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the falling edge time sum;

[0043] Under the condition that the rising edge time sum is greater than 20 milliseconds and the falling edge time sum is greater than 20 milliseconds:

[0044] If the rising edge time sum is greater than or equal to the falling edge time sum, the target equipotential point is the second rising edge equipotential point separated from the current equipotential point, and the target action time is the difference between 40 milliseconds and the rising edge time sum;

[0045] If the sum of the rising edge times is less than the sum of the falling edge times, the target equipotential point is the second falling edge equipotential point separated from the current equipotential point, and the target action time is the difference between 40 milliseconds and the sum of the falling edge times.

[0046] In a second aspect, the present application provides a reactive power compensation system, which includes: a control circuit, a secondary current transformer, a grid-side busbar, a relay, and a capacitor;

[0047] The secondary current transformer, the grid-side busbar, the relay, and the capacitor are all electrically connected to the control circuit, and the control circuit is used to implement the method steps as described in the first aspect.

[0048] In a third aspect, the present application provides a control device, which includes: a memory and a processor. The memory stores a computer program that can run on the processor. The feature is that when the processor executes the program, it implements the method steps as described in the first aspect.

[0049] In a fourth aspect, the present application provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the method steps as described in the first aspect.

[0050] Advantages of the embodiments of the present application:

[0051] In the embodiments of the present application, by calculating the current reactive power in real time and detecting the current equipotential point in real time, when the current reactive power is greater than or equal to the current capacitance of the capacitor side, that is, when the capacitor needs to be connected, according to the current time, the mechanical delay time of the relay, and the current equipotential point, the equipotential point closest to the current time, that is, the target equipotential point, is determined, and the target action time is calculated. Starting from the current time, after delaying the target action time, a relay control signal is output, so that the capacitor on the capacitor side is connected to the grid side at the target equipotential point to perform reactive power compensation on the grid side to provide a fast reactive power compensation response.

[0052] For what is provided in the above second aspect and each possible design of the second aspect, the beneficial effects can refer to the beneficial effects brought by the above first aspect and each possible implementation manner of the first aspect, and will not be elaborated here. Description of the Drawings

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other embodiments can also be obtained based on these drawings.

[0054] Figure 1 Schematic diagram of the topology structure of the reactive power compensation system according to the embodiment of the present application;

[0055] Figure 2 Schematic flow chart of a reactive power compensation method provided by the embodiment of the present application;

[0056] Figure 3 Schematic diagram of the sine wave voltage signal and the equipotential point of the capacitor voltage within a period provided by the embodiment of the present application;

[0057] Figure 4 Schematic diagram of the time relationship of the equipotential points provided by the embodiment of the present application;

[0058] Figure 5 A decision strategy diagram provided by the embodiment of the present application. Detailed implementation manners

[0059] In the present application, "at least one" means one or more, and "a plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone, where A and B may be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. "At least one (item)" or its similar expression refers to any combination of these items, including any combination of single item (item) or plural items (items). For example, at least one (item) of a alone, b alone or c alone may represent: a alone, b alone, c alone, the combination of a and b, the combination of a and c, the combination of b and c, or the combination of a, b and c, where a, b, c may be single or multiple. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0060] The orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "left", "right", "front", "rear", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0061] The terms "connected" and "linked" should be understood in a broad sense. For example, the "connection" or "linkage" of a circuit structure can refer not only to a physical connection but also to an electrical connection or a signal connection. For example, it can be a direct connection, i.e., a physical connection, or it can be indirectly connected through at least one intermediate component, as long as the circuit is connected. It can also be the connection inside two components; the signal connection can be made not only through a circuit for signal connection but also through a media medium for signal connection. For example, radio waves. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0062] To clearly understand the solution in this application, the reactive power compensation system is first introduced. See Figure 1 , Figure 1 which is a schematic diagram of the topology structure of the reactive power compensation system, as Figure 1 shown. The reactive power compensation system can include: a control circuit, a secondary current transformer, a grid-side bus, a relay, and a capacitor.

[0063] Among them, see Figure 1 , the grid-side bus includes a first phase line A, a second phase line B, a third phase line C, and a neutral line N. For the commercial power, the AC voltage value between the first phase line A and the second phase line B is 380VAC, the AC voltage value between the first phase line A and the third phase line C is 380VAC, and the AC voltage value between the second phase line B and the third phase line C is 380VAC; the AC voltage value between the first phase line A and the neutral line N is 220VAC, the AC voltage value between the second phase line B and the neutral line N is 220VAC, and the AC voltage value between the third phase line C and the neutral line N is 220VAC.

[0064] Normally, a primary current transformer is provided on the grid-side bus. The primary current transformer is electrically connected to the secondary current transformer and the grid-side bus respectively, and is used to realize the transformation of the grid-side current value and transmit the converted current value to the secondary current transformer. In one example, the input current of the primary current transformer can be 100A (ampere), and the output current of the primary current transformer can be 5A.

[0065] The secondary current transformer transforms the current output by the primary current transformer again and transmits the converted current to the control circuit. The control circuit can collect the three-phase currents on the grid side through the secondary current transformer and the primary current transformer. In one example, the input current of the secondary current transformer can be 0A to 5A, and the output current of the secondary current transformer can be 0A to 100mA (milliampere).

[0066] The control circuit is electrically connected to the first phase line A, the second phase line B, the third phase line C, and the neutral line N, and is used to collect the three-phase voltages on the grid side (i.e., UA, UB, UC). The control circuit is also electrically connected to the capacitor and is used to collect the voltage value of the capacitor (i.e., UA-C, UB-C, UC-C).

[0067] The control circuit may further include a relay driving circuit, which is used to output a relay control signal to drive the relay to close or open, so that the capacitor is connected to or disconnected from the grid side.

[0068] Based on the above reactive power compensation system, in order to provide a fast reactive power compensation response, an embodiment of the present application provides a reactive power compensation method, which includes: obtaining a synchronous rotation angle; obtaining the current three-phase voltages and current three-phase currents on the grid side, and calculating based on the synchronous rotation angle, the current three-phase voltages, and the current three-phase currents according to the phase-locked loop algorithm to obtain the current reactive power; simultaneously obtaining the current capacitor voltage on the capacitor side, detecting the potential point on the grid side whose voltage value is equal to the current capacitor voltage to obtain an equipotential point, and determining the current equipotential point according to the time interval between two adjacent equipotential points, where the equipotential points include rising-edge equipotential points and falling-edge equipotential points; when the current reactive power is greater than or equal to the current capacitor capacity on the capacitor side, recording the current time, and obtaining a target action time and a target equipotential point based on a determination strategy according to the current time, the mechanical delay time, and the current equipotential point; starting from the current time, outputting a relay control signal after delaying the target action time, so that the capacitor on the capacitor side is connected to the grid side at the target equipotential point to perform reactive power compensation on the grid side.

[0069] In the embodiment of the present application, by calculating the current reactive power in real time and detecting the current equipotential point in real time, when the current reactive power is greater than or equal to the current capacitor capacity on the capacitor side, that is, when the capacitor needs to be connected, according to the current time, the mechanical delay time of the relay, and the current equipotential point, the equipotential point closest to the current time, that is, the target equipotential point, is determined, and the target action time is calculated. Starting from the current time, a relay control signal is output after delaying the target action time, so that the capacitor on the capacitor side is connected to the grid side at the target equipotential point to perform reactive power compensation on the grid side to provide a fast reactive power compensation response.

[0070] The following introduces the reactive power compensation method provided by the present application in combination with specific embodiments. See Figure 2 , Figure 2 is a schematic flowchart of a reactive power compensation method provided by an embodiment of the present application. As Figure 2 shown, the reactive power compensation method includes:

[0071] S1, obtaining a synchronous rotation angle.

[0072] The control circuit may include a processor for implementing the reactive power compensation method in this application. The voltage on the grid side is a sine wave signal with a frequency of 50HZ, that is, 20ms, and the synchronous rotation angle is the phase angle of the sine wave signal. In one example, the synchronous rotation angle of the three-phase voltage can be extracted by detecting the three-phase voltage on the grid side and performing phase-locked calculation using the phase-locked loop algorithm.

[0073] S2. Obtain the current three-phase voltage and current on the grid side, and calculate based on the phase-locked loop algorithm according to the synchronous rotation angle, the current three-phase voltage, and the current three-phase current to obtain the current reactive power; and obtain the current capacitor voltage on the capacitor side, detect the equipotential point on the grid side with the same voltage value as the current capacitor voltage to obtain the equipotential point, and determine the current equipotential point according to the time interval between two adjacent equipotential points, where the equipotential point includes the rising-edge equipotential point and the falling-edge equipotential point.

[0074] To calculate the reactive power in real time, it is necessary to collect the three-phase voltage and current on the grid side in real time to obtain the current three-phase voltage and current, and perform coordinate transformation calculation based on the phase-locked loop algorithm according to the synchronous rotation angle, the current three-phase voltage, and the current three-phase current to obtain the current reactive power.

[0075] When calculating the current reactive power, it is also necessary to synchronously detect the equipotential point. The voltage inside the capacitor on the capacitor side can be regarded as a DC voltage signal. As time goes by, the voltage of the capacitor will slowly drop to 0V. Refer to Figure 3 , Figure 3 is a schematic diagram of the sine wave voltage signal and the equipotential point of the capacitor voltage in one cycle. As Figure 3 shown, in the sine wave voltage signal in one cycle on the grid side, there are two equipotential points between the capacitor voltage of the capacitor and the sine wave voltage signal. Figure 3 Taking the single-phase voltage as an example for illustration, that is, the sine wave voltage signal UA between the first phase line A and the neutral line N. The period of the sine wave voltage signal UA is 20ms, and UA-C is the current capacitor voltage of the capacitor on the capacitor side. The two equipotential points are the equipotential point 1 and the equipotential point 2.

[0076] Refer to Figure 3, obtain the current capacitor voltage on the capacitor side, compare the current capacitor voltage with the voltage on the grid side, and it is possible to detect a potential point on the grid side with a voltage value equal to the current capacitor voltage, thereby obtaining an equipotential point. Additionally, by comparing the difference between the current capacitor voltage and the voltage on the grid side, it can be determined whether the equipotential point is a rising-edge equipotential point or a falling-edge equipotential point. For example, if the difference between the current capacitor voltage and the voltage on the grid side is first positive and then negative, the equipotential point where the voltage values of the current capacitor voltage and the voltage on the grid side are equal is a rising-edge equipotential point; if the difference between the current capacitor voltage and the voltage on the grid side is first negative and then positive, the equipotential point where the voltage values of the current capacitor voltage and the voltage on the grid side are equal is a falling-edge equipotential point. Figure 3 Among them, equipotential point 1 is a rising-edge equipotential point, and equipotential point 2 is a falling-edge equipotential point.

[0077] Since the period of the sinusoidal voltage signal is 20 ms, within consecutive periods, equipotential points will appear cyclically. Based on the time interval between two adjacent equipotential points, the state of the equipotential point can be continuously judged to determine the current equipotential point. Through the current equipotential point, the next equipotential point can be inferred, preparing for the subsequent connection of the capacitor. The current equipotential point will be explained in detail in subsequent embodiments.

[0078] It should be noted that calculating the current reactive power and detecting the equipotential point are carried out synchronously and continuously.

[0079] S3, when the current reactive power is greater than or equal to the current capacitor capacity on the capacitor side, record the current time, and based on the current time, mechanical delay time, and current equipotential point, obtain the target action time and target equipotential point according to the determination strategy.

[0080] The unit of the current capacitor capacity of the capacitor on the capacitor side is var (reactive power). For example, the current capacitor capacity is 1 Kvar (reactive power). Compare the current reactive power with the current capacitor capacity on the capacitor side in real time. When the current reactive power is greater than or equal to the current capacitor capacity on the capacitor side, it is considered that the capacitor needs to be connected. At this time, record the current time, and based on the current time, mechanical delay time, and current equipotential point. Among them, the mechanical delay time is the fixed mechanical delay during the relay closing process, and the mechanical delay time needs to be taken into account when calculating the target action time. The next equipotential point can be inferred through the current equipotential point.

[0081] In this way, according to the current time, mechanical delay time, and current equipotential point, based on the determination strategy, the fastest target equipotential point when the capacitor can be connected in the future and the time required when the target equipotential point arrives, that is, the target action time, can be obtained.

[0082] S4. Starting from the current moment, after delaying for the target action time, output a relay control signal so that the capacitor on the capacitor side is connected to the grid side at the target equipotential point to perform reactive power compensation on the grid side.

[0083] After obtaining the target action time and the target equipotential point, starting from the current moment, output a relay control signal after delaying for the target action time. After the relay receives the relay control signal, it closes, the relay contacts close, and the capacitor on the capacitor side is connected to the grid side at the target equipotential point, realizing reactive power compensation for the grid side.

[0084] The prior art is to connect the capacitor at zero point, while in this application, the capacitor on the capacitor side is connected at the equipotential point, and this equipotential point can be any voltage value of the capacitor. The specific voltage value of the equipotential point in this application is not limited.

[0085] In the embodiment of this application, by calculating the current reactive power in real time and detecting the current equipotential point in real time, when the current reactive power is greater than or equal to the current capacitance of the capacitor side, that is, when it is necessary to connect the capacitor, according to the current moment, the mechanical delay time of the relay, and the current equipotential point, determine the equipotential point closest to the current moment, that is, the target equipotential point, and calculate the target action time. Starting from the current moment, output a relay control signal after delaying for the target action time so that the capacitor on the capacitor side is connected to the grid side at the target equipotential point to perform reactive power compensation on the grid side to provide a fast reactive power compensation response.

[0086] In a possible embodiment, the above step S1 includes:

[0087] S11. Obtain the three-phase voltage of the grid side in real time.

[0088] After the control circuit is powered on, it collects the three-phase voltage and three-phase current of the grid side. After obtaining the three-phase voltage of the grid side, extract the synchronous rotation angle θ from the three-phase voltage.

[0089] S12. Use a phase-locked loop for phase locking to obtain the synchronous rotation angle.

[0090] Since the output of the phase-locked loop (PLL) is unstable, it is often necessary to wait for a period of time, also known as the locking time, and this locking time can be 3 - 5 cycles (i.e., 60ms - 100ms), until the output of the phase-locked loop is stable. The phase-locked loop can be used for phase locking to obtain the synchronous rotation angle θ.

[0091] In a possible embodiment, in the above step S2, the step of calculating the current reactive power may include:

[0092] S21. Perform Clarke coordinate transformation on the current three-phase voltage to obtain the first voltage coordinate component and the second voltage coordinate component.

[0093] Obtain the current three-phase voltage, namely , , , perform Clarke coordinate transformation on the current three-phase voltage, convert the three-phase stationary coordinate system to the components in the two-phase stationary coordinate system (αβ), and obtain the first voltage coordinate component and the second voltage coordinate component .

[0094] Among them, the coordinate transformation formula is: , .

[0095] S22. Perform Clarke coordinate transformation on the current three-phase current to obtain the first current coordinate component and the second current coordinate component.

[0096] Obtain the current three-phase current, namely , , , perform Clarke coordinate transformation on the current three-phase current, convert the three-phase stationary coordinate system to the components in the two-phase stationary coordinate system (αβ), and obtain the first current coordinate component and the second current coordinate component .

[0097] Among them, the coordinate transformation formula is: , .

[0098] S23. Use the synchronous rotation angle to perform Park coordinate transformation on the first voltage coordinate component and the second voltage coordinate component to obtain the third voltage coordinate component and the fourth voltage coordinate component.

[0099] Use the synchronous rotation angle θ output by the phase-locked loop to perform Park coordinate transformation on the two-phase stationary coordinate system (αβ), convert it to the dq rotating coordinate system synchronized with the power grid, and obtain the third voltage coordinate component and the fourth voltage coordinate component .

[0100] Among them, the coordinate transformation formula is: , .

[0101] S24. Use the synchronous rotation angle to perform Park coordinate transformation on the first current coordinate component and the second current coordinate component to obtain the third current coordinate component and the fourth current coordinate component.

[0102] Using the synchronous rotation angle θ output by the phase-locked loop, the two-phase stationary coordinate system (αβ) is subjected to Park coordinate transformation to be converted into a dq rotating coordinate system synchronized with the power grid, and the third current coordinate component is obtained. and the fourth current coordinate component .

[0103] Among them, the coordinate transformation formula is: , .

[0104] S25, according to the formula , the current reactive power is calculated, where Q is the current reactive power, is the third voltage coordinate component, is the fourth voltage coordinate component, is the third current coordinate component, is the fourth current coordinate component.

[0105] In the embodiment of the present application, based on the phase-locked loop algorithm, coordinate transformation is performed according to the synchronous rotation angle, the current three-phase voltage, and the current three-phase current, and the current reactive power can be calculated.

[0106] In a possible embodiment, in the above step S2, the steps of obtaining the equipotential point include:

[0107] S26, obtaining the current capacitor voltage on the capacitor side.

[0108] S27, at the equipotential point where the rising edge of the sine wave on the power grid side is equal to the voltage value of the current capacitor voltage, the rising edge equipotential point is obtained.

[0109] S28, at the equipotential point where the falling edge of the sine wave on the power grid side is equal to the voltage value of the current capacitor voltage, the falling edge equipotential point is obtained.

[0110] Obtain the current capacitor voltage on the capacitor side, compare the current capacitor voltage with the voltage on the power grid side, and the equipotential point where the voltage value equal to the current capacitor voltage is detected on the power grid side can be obtained, and the equipotential point is obtained. By comparing the difference between the current capacitor voltage and the voltage on the power grid side, it can be determined whether the equipotential point is the rising edge equipotential point or the falling edge equipotential point.

[0111] Specifically, if the difference between the current capacitor voltage and the voltage on the power grid side is first positive and then negative, the rising edge equipotential point is obtained at the equipotential point where the rising edge of the sine wave on the power grid side is equal to the voltage value of the current capacitor voltage; if the difference between the current capacitor voltage and the voltage on the power grid side is first negative and then positive, the falling edge equipotential point is obtained at the equipotential point where the falling edge of the sine wave on the power grid side is equal to the voltage value of the current capacitor voltage.

[0112] In a possible embodiment, in the above step S2, the step of determining the current equipotential point includes:

[0113] S29. Obtain two adjacent rising-edge equipotential points to obtain a first rising-edge equipotential point and a second rising-edge equipotential point.

[0114] See Figure 4 , Figure 4 which is a schematic diagram of the time relationship of equipotential points provided by the embodiment of the present application. As Figure 4 shown, mark the rising-edge equipotential points as T U . The sine wave signal on the grid side is continuous. Obtain two adjacent rising-edge equipotential points to obtain a first rising-edge equipotential point T U0 and a second rising-edge equipotential point T U1 .

[0115] S210. Calculate the time interval between the first rising-edge equipotential point and the second rising-edge equipotential point to obtain a first time interval.

[0116] Calculate the time interval between the first rising-edge equipotential point T U0 and the second rising-edge equipotential point T U1 to obtain a first time interval ΔT U = T U1 - T U0 .

[0117] S211. Obtain two adjacent falling-edge equipotential points to obtain a first falling-edge equipotential point and a second falling-edge equipotential point.

[0118] See Figure 4 , and mark the falling-edge equipotential points as T D . The sine wave signal on the grid side is continuous. Obtain two adjacent falling-edge equipotential points to obtain a first falling-edge equipotential point T D0 and a second falling-edge equipotential point T D1 .

[0119] S212. Calculate the time interval between the first falling-edge equipotential point and the second falling-edge equipotential point to obtain a second time interval.

[0120] Calculate the time interval between the first falling-edge equipotential point T D0 and the second falling-edge equipotential point T D1 to obtain a second time interval ΔT D = T D1 - T D0 .

[0121] S213. If both the first time interval and the second time interval are equal to the interval threshold, determine that the equipotential point is in a stable state, and return to execute the steps: Obtain two adjacent rising-edge equipotential points to get a first rising-edge equipotential point and a second rising-edge equipotential point. Each time when returning to execute the steps: Obtain two adjacent rising-edge equipotential points to get a first rising-edge equipotential point and a second rising-edge equipotential point, update the second rising-edge equipotential point or the second falling-edge equipotential point of the current detection period correspondingly as the first rising-edge equipotential point or the first falling-edge equipotential point of the next detection period.

[0122] The theoretical value of the interval threshold is the period of the sine wave, which is equal to 20 ms. In actual project applications, the interval threshold can have a deviation, approximately 20 ms, such as 20 ms ± 1 ms.

[0123] If the first time interval ΔT U and the second time interval ΔT D are both equal to the interval threshold, then determine that the equipotential point is in a stable state, that is, the rising-edge equipotential point or the falling-edge equipotential point is in the correct stable state. Detecting the state of the equipotential point is a continuous process. After determining that the equipotential point is in a stable state, continue to return to execute the steps: Obtain two adjacent rising-edge equipotential points to get a first rising-edge equipotential point and a second rising-edge equipotential point, and continuously determine whether the equipotential point is in a stable state.

[0124] Completing a process of determining that the equipotential point is in a stable state is regarded as one detection period. After one detection period, it is necessary to update the second rising-edge equipotential point T U1 or the second falling-edge equipotential point T D1 of the current detection period correspondingly as the first rising-edge equipotential point T U0 or the first falling-edge equipotential point T D0 of the next detection period. That is, after determining that the equipotential point is in a stable state, replace the second rising-edge equipotential point T U1 with the first rising-edge equipotential point T U0 , and replace the second falling-edge equipotential point T D1 with the first falling-edge equipotential point T D0 , and continue to perform the detection of the next rising-edge equipotential point or falling-edge equipotential point, as well as the process of determining whether the equipotential point is in a stable state.

[0125] S214. Determine the first rising-edge equipotential point or the first falling-edge equipotential point as the current equipotential point.

[0126] Since after completing a process of determining that the equipotential point is in a stable state, it is necessary to replace the second rising-edge equipotential point T U1 with the first rising-edge equipotential point TU0 , the second falling-edge equipotential point T D1 is replaced with the first falling-edge equipotential point T D0 , then there is always the first rising-edge equipotential point T U0 or the first falling-edge equipotential point T D0 , then the existing first rising-edge equipotential point T after update U0 or the first falling-edge equipotential point T D0 is determined as the current equipotential point.

[0127] In the embodiment of the present application, determining the equipotential point as the stable state and determining the first rising-edge equipotential point or the first falling-edge equipotential point as the current equipotential point are to be able to calculate the next equipotential point closest to the current moment from the correct equipotential point when the capacitor needs to be put in, for the input of the capacitor to provide a fast reactive power compensation response.

[0128] In a possible embodiment, the above step S3 includes:

[0129] S31, calculate the time difference between the first rising-edge equipotential point and the current moment to obtain the rising-edge interval.

[0130] When the current reactive power is greater than or equal to the current capacitance of the capacitor side, that is, when the capacitor needs to be put in, at this time, it is necessary to calculate that the upcoming rising-edge equipotential point or falling-edge equipotential point is the fastest relay closing action time point, and the capacitor needs to be put in at this time point.

[0131] The current equipotential point is the first rising-edge equipotential point T U0 or the first falling-edge equipotential point T D0 .

[0132] Therefore, it is necessary to calculate the time difference between the first rising-edge equipotential point T U0 and the current moment to obtain the rising-edge interval ΔT UB .

[0133] S32, calculate the time difference between the first falling-edge equipotential point and the current moment to obtain the falling-edge interval.

[0134] Similarly, calculate the time difference between the first falling-edge equipotential point T D0 and the current moment to obtain the falling-edge interval ΔT DB .

[0135] S33, calculate the sum of the rising-edge interval and the mechanical delay time to obtain the rising-edge time sum.

[0136] The mechanical delay time is a fixed mechanical delay during the relay's closing process, and the mechanical delay time needs to be taken into account when calculating the target action time. When the type of the relay is determined, the mechanical delay time is also a fixed value, and the mechanical delay time is denoted as T j .

[0137] In this way, calculate the rising edge interval ΔT UB and the mechanical delay time T j The sum of them gives the rising edge time sum ΔT UM . That is, ΔT UM= ΔT UB +T j .

[0138] S34, calculate the sum of the falling edge interval and the mechanical delay time to obtain the falling edge time sum.

[0139] Similarly, calculate the falling edge interval ΔT DB and the mechanical delay time T j The sum of them gives the falling edge time sum ΔT DM . That is, ΔT DM= ΔT DB +T j .

[0140] S35, based on the rising edge time sum and the falling edge time sum, and according to the determination strategy, obtain the target action time and the target equipotential point.

[0141] According to the rising edge time sum ΔT UM and the falling edge time sum ΔT DM , based on the determination strategy, the target equipotential point where the capacitor can be connected and the target action time closest to the current moment can be calculated.

[0142] In a possible embodiment, refer to Figure 5 , Figure 5 which is a determination strategy diagram provided by an embodiment of this application. As Figure 5 shown, the above step S35 may include:

[0143] S351, when the rising edge time sum ΔT UM is less than or equal to 20 milliseconds and the falling edge time sum ΔT DM is less than or equal to 20 milliseconds:

[0144] If the rising edge time sum ΔT UM is greater than or equal to the falling edge time sum ΔT DM , then the target equipotential point is the next rising edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the rising edge time sum.

[0145] If the rising edge time and ΔT UM are less than the falling edge time and ΔT DM , then the target equipotential point is the next falling edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the sum of the falling edge time.

[0146] First, perform a time condition determination: Compare the rising edge time and ΔT UM with the falling edge time and ΔT DM and 20 milliseconds to determine their magnitude relationship. When the rising edge time and ΔT UM ≤ 20 milliseconds, and the falling edge time and ΔT DM ≤ 20 milliseconds, then it is considered that the target equipotential point closest to the current moment where the capacitor can be connected is the rising edge equipotential point or the falling edge equipotential point within the current cycle.

[0147] Secondly, perform an auxiliary judgment: Compare the rising edge time and ΔT UM with the falling edge time and ΔT DM . Since the longer the rising edge time and ΔT UM or the falling edge time and ΔT DM , the shorter the time until the corresponding next equipotential point arrives. Therefore, if the rising edge time and ΔT UM ≥ the falling edge time and ΔT DM , then the determination result is: The target equipotential point is the next rising edge equipotential point adjacent to the current equipotential point, that is, connect the capacitor at the next rising edge equipotential point. And the target action time is 20 ms - ΔT UM , and the relay performs an energizing action after (20 ms - ΔT UM ) time.

[0148] If the rising edge time and ΔT UM < the falling edge time and ΔT DM , then the determination result is: The target equipotential point is the next falling edge equipotential point adjacent to the current equipotential point, that is, connect the capacitor at the next falling edge equipotential point. And the target action time is 20 ms - ΔT DM , and the relay performs an energizing action after (20 ms - ΔT DM ) time.

[0149] S352, under the condition that the rising edge time and ΔT UM are less than or equal to 20 milliseconds, and the falling edge time and ΔT DM are greater than 20 milliseconds: Then the target equipotential point is the next rising edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the sum of the rising edge time.

[0150] Similarly, if the rising edge time and ΔTUM or the falling edge time and ΔT DM is greater than 20 milliseconds, it is considered that the equipotential point is in the next cycle. Therefore, when the rising edge time and ΔT UM ≤ 20 milliseconds, and the falling edge time and ΔT DM > 20 milliseconds, it is considered that the target equipotential point closest to the current moment where the capacitor can be connected is the rising edge equipotential point in the current cycle, and no auxiliary judgment is required.

[0151] Then the determination result is: the target equipotential point is the next rising edge equipotential point adjacent to the current equipotential point, that is, the capacitor is connected at the next rising edge equipotential point, and the target action time is 20ms - ΔT UM , and the relay performs a closing action after (20ms - ΔT UM ) time.

[0152] S353, when the rising edge time and ΔT UM is greater than 20 milliseconds, and the falling edge time and ΔT DM is less than or equal to 20 milliseconds: Then the target equipotential point is the next falling edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the sum of the falling edge time.

[0153] Similarly, when the rising edge time and ΔT UM > 20 milliseconds, and the falling edge time and ΔT DM ≤ 20 milliseconds, it is considered that the target equipotential point closest to the current moment where the capacitor can be connected is the falling edge equipotential point in the current cycle, and no auxiliary judgment is required.

[0154] Then the determination result is: the target equipotential point is the next falling edge equipotential point adjacent to the current equipotential point, that is, the capacitor is connected at the next rising edge equipotential point, and the target action time is 20ms - ΔT DM , and the relay performs a closing action after (20ms - ΔT DM ) time.

[0155] S354, when the rising edge time and ΔT UM is greater than 20 milliseconds, and the falling edge time and ΔT DM is greater than 20 milliseconds:

[0156] If the rising edge time and ΔT UM is greater than or equal to the falling edge time and ΔT DM , then the target equipotential point is the second rising edge equipotential point separated from the current equipotential point, and the target action time is the difference between 40 milliseconds and the sum of the rising edge time.

[0157] If the rising edge time and ΔTUM Less than the falling edge time and ΔT DM , the target equipotential point is the second falling edge equipotential point separated from the current equipotential point, and the target action time is the difference between 40 milliseconds and the sum of the falling edge time and ΔT.

[0158] First, perform a time condition determination: Compare the rising edge time and ΔT UM and the falling edge time and ΔT DM with 20 milliseconds. When the rising edge time and ΔT UM > 20 milliseconds, and the falling edge time and ΔT DM > 20 milliseconds, it is considered that the target equipotential point closest to the current moment where the capacitor can be switched in is the rising edge equipotential point or the falling edge equipotential point in the next cycle.

[0159] Secondly, perform an auxiliary determination: Compare the rising edge time and ΔT UM and the falling edge time and ΔT DM . Since the longer the rising edge time and ΔT UM or the falling edge time and ΔT DM , the shorter the time for the corresponding next equipotential point to arrive. Therefore, if the rising edge time and ΔT UM ≧ the falling edge time and ΔT DM , the determination result is: The target equipotential point is the second rising edge equipotential point separated from the current equipotential point, that is, the capacitor is switched in at the second rising edge equipotential point separated. And the target action time is 40ms - ΔT UM , and the relay performs a closing action after (40ms - ΔT UM ) time.

[0160] If the rising edge time and ΔT UM < the falling edge time and ΔT DM , the determination result is: The target equipotential point is the second falling edge equipotential point separated from the current equipotential point, that is, the capacitor is switched in at the second falling edge equipotential point separated. And the target action time is 40ms - ΔT DM , and the relay performs a closing action after (40ms - ΔT DM ) time.

[0161] The embodiment of the present application also provides a reactive power compensation system. Refer to Figure 1 , this system includes: a control circuit, a secondary current transformer, a grid-side busbar, a relay, and a capacitor;

[0162] The secondary current transformer, the grid-side busbar, the relay, and the capacitor are all electrically connected to the control circuit, and the control circuit is used to implement the above-mentioned steps of the reactive power compensation method.

[0163] An embodiment of the present application further provides a control device, including: a memory and a processor, where the memory stores a computer program that can run on the processor, and when the processor executes the program, the steps of the reactive power compensation method described above are implemented.

[0164] The memory may include a random access memory (Random Access Memory, abbreviated as RAM), and may also include a non-volatile memory, such as at least one disk memory. Optionally, the memory may also be at least one storage device located far from the aforementioned processor.

[0165] The aforementioned processor may be a general-purpose processor, including a central processing unit (Central Processing Unit, abbreviated as CPU), a network processor (Network Processor, abbreviated as NP), etc.; it may also be a digital signal processor (Digital Signal Processor, abbreviated as DSP), an application specific integrated circuit (Application Specific Integrated Circuit, abbreviated as ASIC), a field programmable gate array (Field-Programmable Gate Array, abbreviated as FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0166] In another embodiment provided by the present application, a computer-readable storage medium is further provided. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in any one of the above embodiments is implemented.

[0167] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present invention are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wirelessly (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that the computer can access or a data storage device such as a server or data center that includes one or more integrated available media. The available medium can be a magnetic medium (such as a floppy disk, hard disk, magnetic tape), an optical medium (such as a DVD), or a semiconductor medium (such as a solid state disk (SSD)).

[0168] Finally, it should be noted that the above embodiments are only specific implementation manners of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A reactive power compensation method, characterized in that, The reactive power compensation method includes: Obtaining a synchronous rotation angle; Obtaining the current three-phase voltage and current on the grid side, calculating based on the phase-locked loop algorithm according to the synchronous rotation angle, the current three-phase voltage, and the current three-phase current to obtain the current reactive power; and obtaining the current capacitor voltage on the capacitor side, detecting a potential point on the grid side with a voltage value equal to the current capacitor voltage to obtain an equipotential point, where the equipotential point includes a rising-edge equipotential point and a falling-edge equipotential point; obtaining two adjacent rising-edge equipotential points to obtain a first rising-edge equipotential point and a second rising-edge equipotential point; Calculating the time interval between the first rising-edge equipotential point and the second rising-edge equipotential point to obtain a first time interval; Obtaining two adjacent falling-edge equipotential points to obtain a first falling-edge equipotential point and a second falling-edge equipotential point; Calculating the time interval between the first falling-edge equipotential point and the second falling-edge equipotential point to obtain a second time interval; If both the first time interval and the second time interval are equal to the interval threshold, determining that the equipotential point is in a stable state, and returning to execute the step: obtaining two adjacent rising-edge equipotential points to obtain a first rising-edge equipotential point and a second rising-edge equipotential point. Each time returning to execute the step: obtaining two adjacent rising-edge equipotential points to obtain a first rising-edge equipotential point and a second rising-edge equipotential point, updating the second rising-edge equipotential point or the second falling-edge equipotential point of the current detection period to the first rising-edge equipotential point or the first falling-edge equipotential point of the next detection period; Determining the first rising-edge equipotential point or the first falling-edge equipotential point as the current equipotential point; When the current reactive power is greater than or equal to the current capacitor capacity on the capacitor side, recording the current moment; Calculating the time difference between the first rising-edge equipotential point and the current moment to obtain a rising-edge interval; Calculating the time difference between the first falling-edge equipotential point and the current moment to obtain a falling-edge interval; Calculating the sum of the rising-edge interval and the mechanical delay time to obtain a rising-edge time sum; Calculating the sum of the falling-edge interval and the mechanical delay time to obtain a falling-edge time sum; Based on the rising-edge time sum and the falling-edge time sum, obtaining a target action time and a target equipotential point based on a determination strategy; Starting from the current moment, delaying the target action time and then outputting a relay control signal so that the capacitor on the capacitor side is connected to the grid side at the target equipotential point to perform reactive power compensation on the grid side.

2. The reactive power compensation method according to claim 1, characterized in that The obtaining of the synchronous rotation angle includes: Real-time obtaining of the three-phase voltage on the grid side; Using a phase-locked loop for phase locking to obtain the synchronous rotation angle.

3. The reactive power compensation method according to claim 1, characterized in that The calculating based on the phase-locked loop algorithm according to the synchronous rotation angle, the current three-phase voltage, and the current three-phase current to obtain the current reactive power includes: Performing Clarke coordinate transformation on the current three-phase voltage to obtain a first voltage coordinate component and a second voltage coordinate component; Perform Clarke coordinate transformation on the current three-phase current to obtain a first current coordinate component and a second current coordinate component; Utilize the synchronous rotation angle to perform Park coordinate transformation on the first voltage coordinate component and the second voltage coordinate component to obtain a third voltage coordinate component and a fourth voltage coordinate component; Utilize the synchronous rotation angle to perform Park coordinate transformation on the first current coordinate component and the second current coordinate component to obtain a third current coordinate component and a fourth current coordinate component; According to the formula , the current reactive power is calculated, where Q is the current reactive power, is the third voltage coordinate component, is the fourth voltage coordinate component, is the third current coordinate component, is the fourth current coordinate component.

4. The reactive power compensation method according to claim 1, characterized in that The obtaining of the current capacitor voltage on the capacitor side and detecting, on the grid side, a potential point equal to the voltage value of the current capacitor voltage to obtain an equipotential point includes: Obtain the current capacitor voltage on the capacitor side; At the potential point on the grid side where the rising edge of the sine wave is equal to the voltage value of the current capacitor voltage, obtain the rising-edge equipotential point; At the potential point on the grid side where the falling edge of the sine wave is equal to the voltage value of the current capacitor voltage, obtain the falling-edge equipotential point.

5. The reactive power compensation method according to claim 1, characterized in that The obtaining of the target action time and the target equipotential point based on a determination strategy according to the sum of the rising-edge times and the sum of the falling-edge times includes: Under the condition that the sum of the rising-edge times is less than or equal to 20 milliseconds and the sum of the falling-edge times is less than or equal to 20 milliseconds: If the sum of the rising-edge times is greater than or equal to the sum of the falling-edge times, then the target equipotential point is the next rising-edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the sum of the rising-edge times; If the sum of the rising-edge times is less than the sum of the falling-edge times, then the target equipotential point is the next falling-edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the sum of the falling-edge times; Under the condition that the sum of the rising-edge times is less than or equal to 20 milliseconds and the sum of the falling-edge times is greater than 20 milliseconds: then the target equipotential point is the next rising-edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the sum of the rising-edge times; Under the condition that the sum of the rising-edge times is greater than 20 milliseconds and the sum of the falling-edge times is less than or equal to 20 milliseconds: then the target equipotential point is the next falling-edge equipotential point adjacent to the current equipotential point, and the target action time is the difference between 20 milliseconds and the sum of the falling-edge times; Under the condition that the sum of the rising-edge times is greater than 20 milliseconds and the sum of the falling-edge times is greater than 20 milliseconds: If the sum of the rising-edge times is greater than or equal to the sum of the falling-edge times, then the target equipotential point is the second rising-edge equipotential point separated from the current equipotential point, and the target action time is the difference between 40 milliseconds and the sum of the rising-edge times; If the sum of the rising-edge times is less than the sum of the falling-edge times, then the target equipotential point is the second falling-edge equipotential point separated from the current equipotential point, and the target action time is the difference between 40 milliseconds and the sum of the falling-edge times.

6. A reactive power compensation system, characterized in that, The system includes: a control circuit, a secondary current transformer, a grid-side busbar, a relay, and a capacitor; The secondary current transformer, the grid-side busbar, the relay, and the capacitor are all electrically connected to the control circuit, and the control circuit is used to implement the method according to any one of claims 1-5.

7. A control device, comprising: A memory and a processor, the memory stores a computer program that can run on the processor, wherein the processor implements the method according to any one of claims 1-5 when executing the program.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method according to any one of claims 1-5.

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