Relay pull-in control method, intelligent capacitor, reactive compensation system and medium

Abstract

The invention provides a relay pull-in control method, an intelligent capacitor, a reactive compensation system and a medium, and relates to the technical field of electric power. The method comprises the following steps: after a control module receives a pull-in instruction and sends a pull-in electric signal to a relay according to a preset pull-in time length, acquiring N first capacitor voltages from a compensation capacitor, and determining the real pull-in time length of the relay according to the N first capacitor voltages, and after receiving a pull-in instruction next time, sending a pull-in electric signal to the relay according to a preset pull-in duration, then repeatedly collecting the first capacitor voltage until a preset number of real pull-in durations are obtained, determining a final pull-in duration according to the preset number of real pull-in durations, and replacing the preset pull-in duration with the final pull-in duration. And when a suction instruction is received next time, a suction electric signal is sent to the relay according to the replaced preset suction duration, so that impact inrush current is avoided, normal operation of a power grid is ensured, and the service life of the relay is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric power, and in particular to a relay pull-in control method, an intelligent capacitor, a reactive power compensation system and a medium. BACKGROUND

[0002] In a reactive power compensation system of an industrial distribution network, pull-in and breaking of a relay are needed to control compensation capacitors to be connected to or cut off from the power grid, so as to achieve the purpose of reactive power compensation. Since an impulse inrush current may be generated when the compensation capacitors are connected to the power grid, the relay is required to be pulled in when the capacitor voltage of the compensation capacitor is equal to the grid voltage, so as to avoid the generation of the impulse inrush current.

[0003] In the related art, the relay needs to be pulled in when the capacitor voltage of the compensation capacitor is equal to the grid voltage. However, the relay needs to be pulled in after a preset pull-in time interval, and the relay is controlled to be pulled in by sending a pull-in electrical signal to the relay. Therefore, the relay needs to be pulled in when the capacitor voltage of the compensation capacitor is equal to the grid voltage.

[0004] However, there are differences in devices of the relay, or the performance of the relay used for a long time is aged, which may cause an error between the actual pull-in mechanical action time of the relay and the preset pull-in mechanical action time, so that the relay cannot be pulled in when the capacitor voltage of the compensation capacitor is equal to the grid voltage, and an impulse inrush current is generated, which affects the normal operation of the power grid and the service life of the relay. SUMMARY

[0005] The present application provides a relay pull-in control method, an intelligent capacitor, a reactive power compensation system and a medium, to solve the problem that the relay has differences in devices, or the performance of the relay used for a long time is aged, which may cause an error between the actual pull-in mechanical action time of the relay and the preset pull-in mechanical action time, so that the relay cannot be pulled in when the capacitor voltage of the compensation capacitor is equal to the grid voltage, and an impulse inrush current is generated, which affects the normal operation of the power grid and the service life of the relay. The present application achieves the purpose of avoiding the generation of the impulse inrush current, ensuring the normal operation of the power grid and improving the service life of the relay.

[0006] In a first aspect, the present application provides a relay pull-in control method applied to an intelligent capacitor, the intelligent capacitor comprising a control module, a relay and a compensation capacitor, and the method comprises:

[0007] The control module, when receiving a pull-in instruction, acquires N first capacitor voltages from the compensation capacitor connected to the relay according to a preset frequency after sending a pull-in electrical signal to the relay according to a preset pull-in time interval, N being a positive integer.

[0008] The control module determines the actual engagement time of the relay based on the voltages of the N first capacitors;

[0009] When the control module receives a pull-in command again, it sends a pull-in electrical signal to the relay according to the preset pull-in duration and then repeats the steps of acquiring the first capacitor voltage and determining the actual pull-in duration until a preset number of actual pull-in durations are acquired.

[0010] The control module determines the final engagement time based on a preset number of actual engagement times;

[0011] The control module replaces the preset engagement time with the final engagement time, and sends an engagement signal to the relay according to the replaced preset engagement time when it receives the engagement command again.

[0012] In one possible design, the control module determines the actual engagement time of the relay based on the voltages of N first capacitors, including:

[0013] The control module calculates the slopes corresponding to the second to the kth first capacitor voltages among the N first capacitor voltages, and obtains N-2 first slopes, where K equals N-1;

[0014] The control module searches for a second slope that is greater than a first threshold and less than a second threshold from N-2 first slopes. Among the N-2 first slopes, there are multiple consecutive first slopes that are less than or equal to the first threshold before the second slope, and multiple consecutive first slopes that are greater than or equal to the second threshold after the second slope.

[0015] The control module determines the first duration based on the second capacitor voltage. The second capacitor voltage is the capacitor voltage corresponding to the second slope among N first capacitor voltages. The first duration is the time taken by the control module from acquiring the first capacitor voltage to acquiring the second capacitor voltage.

[0016] The control module determines the actual engagement time of the relay based on the first duration.

[0017] In one possible design, after the control module sends an engagement signal to the relay according to a preset engagement time, it performs a second engagement time step of collecting N first capacitor voltages from the compensation capacitor according to a preset frequency. The second engagement time is the shortest engagement time of the relay.

[0018] In one possible design, the control module determines the actual engagement time of the relay based on the first duration, including:

[0019] The control module determines the actual engagement time of the relay by summing the first and second durations.

[0020] In a possible design, before the control module determines the first time length according to the second capacitor voltage, the method further includes:

[0021] The control module collects N first grid voltages from the grid connected with the relay according to the preset frequency after sending the pull-in electric signal to the relay according to the preset pull-in time length in the case that the pull-in instruction is received, and the N first grid voltages correspond to the N first capacitor voltages one by one.

[0022] The control module calculates slopes corresponding to the second first grid voltage to the Kth first grid voltage in the N first grid voltages respectively to obtain N-2 third slopes.

[0023] The control module executes the step of determining the first time length according to the second capacitor voltage when a difference between the second slope and the fourth slope is less than or equal to a third threshold value, the fourth slope is a slope corresponding to the second grid voltage in the N-2 third slopes, and the second grid voltage is a voltage corresponding to the second capacitor voltage in the N first grid voltages.

[0024] In a possible design, after the pull-in electric signal is sent to the relay according to the preset pull-in time length, the method further includes:

[0025] The control module obtains a grid voltage peak value of the grid connected with the relay, and collects a third capacitor voltage from the compensation capacitor.

[0026] The control module executes the step of collecting the N first capacitor voltages from the compensation capacitor according to the preset frequency when the third capacitor voltage is less than or equal to one-half of the grid voltage peak value.

[0027] In a possible design, a time length for collecting the N first capacitor voltages is at least a difference between a longest pull-in time length of the relay and a shortest pull-in time length of the relay.

[0028] The method provided by the first aspect, in the case that the control module receives the attraction instruction, after sending the attraction electric signal to the relay according to the preset attraction time length, the control module collects N first capacitor voltages from the compensation capacitor connected with the relay according to the preset frequency, so as to know the attraction condition of the relay according to the N first capacitor voltages. The control module determines the real attraction time length of the relay according to the N first capacitor voltages; the control module repeats the steps of collecting the first capacitor voltage and determining the real attraction time length in the case that the control module receives the attraction instruction next time, after sending the attraction electric signal to the relay according to the preset attraction time length, until a preset number of real attraction time lengths are obtained; the control module determines the final attraction time length according to the preset number of real attraction time lengths, thereby improving the accuracy of determining the final attraction time length; the control module replaces the preset attraction time length with the final attraction time length, and sends the attraction electric signal to the relay according to the replaced preset attraction time length when receiving the attraction instruction next time, which can ensure that the relay completes the attraction at the first time point when the relay is expected to attract, avoid the occurrence of impulse inrush current, thereby ensuring the normal operation of the power grid and improving the service life of the relay.

[0029] In the second aspect, the present application provides an intelligent capacitor, which comprises a relay, a compensation capacitor and a control module for executing the method in the first aspect and any possible design of the first aspect.

[0030] The first end of the relay is connected with the live wire of the power grid, the second end of the relay is connected with the control module, the third end of the relay is connected with the first end of the compensation capacitor, the second end of the compensation capacitor is connected with the zero line of the power grid, the second end of the control module is connected between the live wire of the power grid and the first end of the relay, and the third end of the control module is connected between the third end of the relay and the first end of the compensation capacitor.

[0031] In the third aspect, the present application provides a reactive power compensation system, which comprises a power grid, a reactive power compensation controller and at least three intelligent capacitors as in the second aspect and any possible design of the second aspect.

[0032] In the fourth aspect, the present application provides a relay attraction control device, which comprises a module for executing the relay attraction control method in the first aspect and any possible design of the first aspect.

[0033] In the fifth aspect, the present application provides an electronic device, which comprises a first processor, and the first processor implements the relay attraction control method in the first aspect and any possible design of the first aspect when executing the computer executable program or instructions in the memory.

[0034] In a sixth aspect, the present application provides an electronic device, comprising a memory and a second processor, the memory storing a computer executable program or instructions, and the second processor executes the computer executable program or instructions to implement the relay pull-in control method in the first aspect and any possible design of the first aspect.

[0035] In a seventh aspect, the present application provides a computer readable storage medium, the computer readable storage medium storing a computer executable program or instructions, and the computer executable program or instructions are executed by a processor to implement the relay pull-in control method in the first aspect and any possible design of the first aspect.

[0036] In an eighth aspect, the present application provides a computer program product, comprising: execution instructions, the execution instructions being stored in a readable storage medium, and at least one processor of an electronic device can read the execution instructions from the readable storage medium, and the at least one processor executes the execution instructions to enable the electronic device to implement the relay pull-in control method in the first aspect and any possible design of the first aspect.

[0037] The above description is only a summary of the technical solutions of the embodiments of the present application, in order to enable the technical means of the embodiments of the present application to be more clearly understood, the embodiments of the present application can be implemented according to the content of the description, and in order to enable the above and other purposes, characteristics and advantages of the embodiments of the present application to be more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 A schematic diagram of relay pull-in provided by an embodiment of the present application.

[0039] Figure 2 A schematic diagram of relay pull-in provided by an embodiment of the present application.

[0040] Figure 3 A schematic diagram of relay pull-in provided by an embodiment of the present application.

[0041] Figure 4 A structural schematic diagram of an intelligent capacitor provided by an embodiment of the present application.

[0042] Figure 5 A structural schematic diagram of an intelligent capacitor provided by an embodiment of the present application.

[0043] Figure 6 A structural schematic diagram of a reactive power compensation system provided by an embodiment of the present application.

[0044] Figure 7 A flowchart of a relay pull-in control method provided by an embodiment of the present application.

[0045] Figure 8A distribution diagram of a first capacitor voltage provided by an embodiment of the present application.

[0046] Figure 9 A method flowchart for determining a real pull-in duration of a relay provided by an embodiment of the present application.

[0047] Figure 10 A method flowchart for determining whether to perform a step of determining a first duration according to a second capacitor voltage provided by an embodiment of the present application.

[0048] Figure 11 A method flowchart for determining whether to perform a step of collecting N first capacitor voltages provided by an embodiment of the present application.

[0049] Figure 12 A structural diagram of a relay pull-in control device provided by an embodiment of the present application.

[0050] Figure 13 A structural diagram of an electronic device provided by an embodiment of the present application.

[0051] Figure 14 A structural diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0052] In the present application, "at least one" means one or more, and "multiple" means two or more. The "and / or" describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the following three cases: A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after it. "At least one of the following" or similar expressions means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c alone can represent: a alone, b alone, c alone, combination of a and b, combination of a and c, combination of b and c, or combination of a, b, and c, where a, b, and c can be single or multiple. In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance.

[0053] The terms "center", "longitudinal", "lateral", "upper", "lower", "left", "right", "front", "back", and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0054] The terms "connected" and "connected" should be interpreted broadly. For example, in circuit structures, "connected" or "connected" can refer not only to physical connections but also to electrical or signal connections. This could be a direct connection (physical connection) or an indirect connection via at least one intermediate component, as long as the circuit is connected. It could also refer to the internal connection between two components. Similarly, a signal connection can refer to a connection via a circuit or a medium, such as radio waves. Those skilled in the art will understand the specific meaning of these terms in this application based on the specific circumstances.

[0055] In related technologies, since inrush current may be generated when switching capacitors, when it is necessary to connect a compensation capacitor to the power grid, the relay is required to activate when the voltage of the compensation capacitor is equal to the voltage of the power grid, so as to avoid inrush current.

[0056] When a relay engages, it takes a certain amount of time to perform the mechanical action of engaging. Therefore, it is usually necessary to send an engagement signal to the relay before the voltage of the compensation capacitor equals the mains voltage, after a preset engagement time interval, so that the relay engages when the voltage of the compensation capacitor equals the mains voltage.

[0057] like Figure 1 As shown, the dashed line represents the curve of the grid voltage, the solid line represents the curve of the capacitor voltage of the compensation capacitor, T0 represents the moment when the capacitor voltage of the compensation capacitor is equal to the grid voltage, and point P represents the relay activation point. When the time taken for the relay to actually complete the mechanical action of activation is equal to the preset activation time, the relay can activate when the capacitor voltage of the compensation capacitor is equal to the grid voltage.

[0058] However, due to differences in components or the aging of relays after long-term use, there may be an error between the actual time taken for the relay to complete the mechanical action of engaging and the preset engagement time. This may prevent the relay from engaging when the voltage of the compensation capacitor is equal to the mains voltage, thus generating inrush current.

[0059] There are two situations where the actual time taken for the relay to complete the mechanical action of engaging differs from the preset engaging time.

[0060] Case 1: The actual time taken for the relay to complete the mechanical action of engaging is longer than the preset engaging time.

[0061] exist Figure 1 On the basis of, such as Figure 2 As shown, when the actual time taken for the relay to complete the mechanical action of engaging exceeds the preset engagement time, the relay will engage after the voltage of the compensation capacitor equals the mains voltage.

[0062] Case 2: the time length for the relay to actually complete the mechanical action of attraction is less than the preset attraction time length.

[0063] In Figure 1 addition, as Figure 3 shown, when the time length for the relay to actually complete the mechanical action of attraction is less than the preset attraction time length, the relay will be attracted before the capacitor voltage of the compensation capacitor is equal to the grid voltage.

[0064] In Figure 2 and Figure 3 , since the relay is not attracted when the capacitor voltage of the compensation capacitor is equal to the grid voltage, an impact inrush current is generated.

[0065] Based on the above exemplary description, the present application provides a relay attraction control method, an intelligent capacitor, a reactive power compensation system and a medium. By collecting a plurality of capacitor voltages during the process of the relay being attracted according to the preset attraction time length, the change of the capacitor voltage is obtained, the real attraction time length of the relay is determined according to the change of the capacitor voltage, and then the preset attraction time length is adjusted according to the real attraction time length, so as to ensure that the relay can be attracted when the capacitor voltage of the compensation capacitor is equal to the grid voltage, thereby avoiding the generation of an impact inrush current, ensuring the normal operation of the grid, and improving the service life of the relay.

[0066] Among them, the relay attraction control method provided by the present application can be executed by an electronic device, for example, an intelligent capacitor, or by a relay attraction control device in the electronic device, for example, a control module in the intelligent capacitor.

[0067] Among them, the electronic device can be an intelligent capacitor, a server, a desktop computer, a mobile phone, a tablet computer, a notebook computer, a wearable device, a vehicle-mounted device, or an augmented reality (AR) / virtual reality (VR) device, etc. The relay attraction control device can be realized by the combination of software and / or hardware, and the relay attraction control device can be an application (APP), a webpage, or a public account, etc., or the relay attraction control device can be a control module in the intelligent capacitor, etc. In order to simplify the description, the embodiments of the present application are described by taking the control module as an example.

[0068] Next, the intelligent capacitor provided by the present application will be introduced in combination with Figure 4 and Figure 5 .

[0069] Please refer to Figure 4 , Figure 4 for a structural schematic diagram of an intelligent capacitor provided by an embodiment of the present application. As Figure 4As shown, the smart capacitor 10 of the present application can include a control module 11, a relay 12, and a compensation capacitor 13.

[0070] The first end of the relay 12 is connected to the fire line L of the power grid, the second end of the relay 12 is connected to the control module 11, and the third end of the relay 12 is connected to the first end of the compensation capacitor 13. The fire line of the power grid includes the A-phase line, the B-phase line, and the C-phase line.

[0071] The second end of the compensation capacitor 13 is connected to the zero line N of the power grid.

[0072] The second end of the compensation capacitor 13 is connected to the zero line N of the power grid.

[0073] The control module 11 can be a microcontroller unit (MCU).

[0074] The control module 11 can control the smart capacitor 10 to be connected to or disconnected from the power grid by controlling the closing and opening of the relay 12. Specifically, when the control module 11 controls the relay 12 to close, the compensation capacitor 13 is connected between the fire line L and the zero line N of the power grid through the relay 12, so as to be connected to the power grid. When the control module 11 controls the relay 12 to open, the compensation capacitor 13 is disconnected from the power grid.

[0075] In some examples, as shown in FIG. 1, the smart capacitor 10 further includes a first analog-to-digital converter (ADC) circuit 14 and a second ADC circuit 15. Figure 5

[0076] The control module 11 can be connected to the fire line of the power grid and the first end of the relay 12 through the first ADC circuit 14, so that the control module 11 can collect the power grid voltage from the power grid through the first ADC circuit 14.

[0077] The control module 11 can be connected to the third end of the relay 12 and the first end of the compensation capacitor 13 through the second ADC circuit 15, so that the control module 11 can collect the capacitor voltage from the compensation capacitor 13 through the second ADC circuit 15.

[0078] In some examples, as shown in FIG. 1, the smart capacitor 10 further includes a driver 16. Figure 5

[0079] ​​The control module 11 can send an attraction electric signal or a breaking electric signal to the relay 12 through the driver 16, so as to control the relay to attract or break.

[0080] In the following, the application is described in detail in combination with Figure 6 The application provides a reactive power compensation system.

[0081] Please refer to Figure 6 , Figure 6 Fig. 1 is a structural schematic diagram of a reactive power compensation system provided by an embodiment of the application. As shown in Fig. 1, the reactive power compensation system of the application can include a power grid 20, a reactive power compensation controller 30 and at least three intelligent capacitors 10. Figure 6

[0082] For example, when the number of the intelligent capacitors 10 is 3, the three intelligent capacitors 10 are connected with the A-phase line, the B-phase line and the C-phase line of the power grid respectively. Figure 6 Fig. 1 is a structural schematic diagram of a reactive power compensation system provided by an embodiment of the application. As shown in Fig. 1, the reactive power compensation system of the application can include a power grid 20, a reactive power compensation controller 30 and at least three intelligent capacitors 10.

[0083] Among them, the power grid 20 is connected with the reactive power compensation controller 30, the at least three intelligent capacitors 10 are connected with the power grid 20 respectively, and the reactive power compensation controller 30 is connected with the at least three intelligent capacitors 10 respectively. The at least three intelligent capacitors 10 can also be connected in communication, Figure 6 which is not shown in Fig. 1.

[0084] Among them, the reactive power compensation controller 30 and the intelligent capacitor 10 can be directly or indirectly connected through wired or wireless communication mode. The intelligent capacitors 10 can be directly or indirectly connected through wired or wireless communication mode.

[0085] Among them, the wired communication mode can adopt coaxial cable, optical fiber, digital subscriber line (DSL) and the like. The wireless communication mode can adopt Bluetooth, infrared, wireless (Wi-Fi), microwave and the like.

[0086] In some specific examples, the reactive power compensation controller 30 and the intelligent capacitor 10 can communicate through ModBus communication protocol based on RS485 physical bus.

[0087] In some specific examples, the reactive power compensation controller 30 and the intelligent capacitor 10 are provided with an RJ45 (Registered Jack 45) interface. The reactive power compensation controller 30 and the intelligent capacitor 10 can communicate through the RJ45 interface according to the RS-485 protocol.

[0088] ​The reactive power compensation controller 30 can determine whether reactive power compensation is needed according to parameters such as the power factor of the power grid 20. When compensation capacitance needs to be connected to the power grid 20, a suitable intelligent capacitor 10 is selected, and a pull-in instruction is sent to the selected intelligent capacitor 10, so that the selected intelligent capacitor 10 connects the compensation capacitance to the power grid 20 to achieve reactive power compensation. When compensation capacitance needs to be disconnected from the power grid 20, a suitable intelligent capacitor 10 is selected, and a disconnecting instruction is sent to the selected intelligent capacitor 10, so that the selected intelligent capacitor 10 disconnects the compensation capacitance from the power grid 20 to achieve reactive power compensation.

[0089] The pull-in instruction is used to instruct the control relay to pull in, and the disconnecting instruction is used to instruct the control relay to disconnect.

[0090] In the following, the embodiments of the present application will be described below with the intelligent capacitor having the structure shown in Figure 4 In the scenario of the reactive power compensation system shown in Figure 6 In combination with Figures 7 to 11 , the relay pull-in control method provided by the present application will be described in detail.

[0091] Please refer to Figure 7 , Figure 7 The flow chart of a relay pull-in control method provided by an embodiment of the present application. As shown in Figure 7 The method comprises the following steps.

[0092] S101, the control module acquires N first capacitor voltages from the compensation capacitor connected to the relay according to a preset frequency after sending a pull-in electric signal to the relay according to a preset pull-in time length in the case of receiving a pull-in instruction.

[0093] The pull-in instruction can be sent by a reactive power compensation controller in a reactive power compensation system to the control module of the intelligent capacitor, and the pull-in instruction is used to instruct the control relay to pull in.

[0094] The control module sends a pull-in electric signal to the relay according to a preset pull-in time length in the case of receiving a pull-in instruction. Specifically, the control module determines a first time point at which the relay is expected to pull in, and sends a pull-in electric signal to the relay at a second time point before the first time point by a preset pull-in time length, so that the relay starts to pull in the mechanical action, so as to connect the compensation capacitor to the power grid.

[0095] The first time point at which the relay is expected to pull in can be a time point at which the capacitor voltage of the compensation capacitor is equal to the voltage of the power grid. At the first time point, the relay pulls in, and the compensation capacitor is connected to the power grid, which can avoid the occurrence of an impulse inrush current. The control module can acquire the voltage of the power grid and the capacitor voltage in real time, so as to determine the first time point.

[0096] The preset engagement time is determined by the controller based on the longest and shortest engagement times of the relay.

[0097] The longest and shortest pull-in times of a relay are inherent properties of the relay at the factory. The time it takes for the relay to complete the mechanical action of pull-in will not exceed the longest pull-in time, and the time it takes to complete the mechanical action of pull-in will not be less than the shortest pull-in time. When the relay is put into use, a preset pull-in time can be set for the relay based on the longest and shortest pull-in times. The preset pull-in time can be the time between the longest and shortest pull-in times, for example, it can be the average of the longest and shortest pull-in times.

[0098] For example, the longest engagement time is 6 milliseconds, the shortest engagement time is 3.5 milliseconds, and the preset engagement time is 4.75 milliseconds or 5 milliseconds. When the preset engagement time is 4.75 milliseconds, the control module sends an engagement signal to the relay 4.75 milliseconds before the first time point.

[0099] The voltage across the compensation capacitor changes before and after the relay is activated. Specifically, for example... Figure 1 As shown, if the relay is activated at time T0, then before time T0, the compensation capacitor is not connected to the power grid, and its voltage decreases slowly over time until it reaches 0. After time T0, the compensation capacitor is connected to the power grid through the activated relay, and its voltage changes with the grid voltage.

[0100] Based on this, since the change in capacitor voltage can reflect the relay's engagement status, during the process of the relay starting its mechanical engagement, the control module can collect N first capacitor voltages from the compensation capacitor at a preset frequency, so as to know the relay's engagement status based on the N first capacitor voltages.

[0101] Where N is a positive integer.

[0102] The preset frequency can be set according to the duration required for the control module to acquire the voltage of a first capacitor.

[0103] In some examples, the control module can acquire the voltage of the first capacitor via a second ADC circuit. Acquiring the first capacitor voltage requires converting the analog signal to a digital signal, and the control module can determine a preset frequency based on the conversion time. For example, if the second ADC circuit takes 100 microseconds to convert the analog signal to a digital signal (i.e., a conversion frequency of 10 kHz), then the preset frequency can be 10 kHz, meaning that one first capacitor voltage is acquired every 100 microseconds.

[0104] It should be noted that since the relay is attracted at least after the shortest attraction time, the N first capacitor voltages should at least include the capacitor voltage after the relay is attracted, that is, the control module needs to ensure that the capacitor voltage after the relay is attracted can be collected when collecting the first capacitor voltage, so as to ensure that the attraction of the relay can be known according to the change of the first capacitor voltage.

[0105] In some examples, the control module can start collecting the first capacitor voltage immediately after sending the attraction electric signal. In this case, the control module needs to collect the first capacitor voltage at least using a time greater than or equal to the longest attraction time, so as to ensure that the capacitor voltage after the relay is attracted is collected.

[0106] For example, the longest attraction time is 6 milliseconds, and the control module can start collecting the first capacitor voltage immediately after sending the attraction electric signal, and at least collect 6 milliseconds.

[0107] In other examples, since the relay needs to complete the attraction mechanical action at least after a time greater than or equal to the shortest attraction time, the control module can also start collecting the first capacitor voltage after waiting for a shortest attraction time after sending the attraction electric signal, so as to reduce the number of collections and save storage resources and computing resources. In this case, the control module needs to collect the first capacitor voltage at least using a time greater than or equal to the difference between the longest attraction time and the shortest attraction time, so as to ensure that the capacitor voltage after the relay is attracted is collected.

[0108] For example, the longest attraction time is 6 milliseconds, and the shortest attraction time is 3.5 milliseconds, and the control module can start collecting the first capacitor voltage after waiting for 3.5 milliseconds after sending the attraction electric signal, and at least collect 2.5 milliseconds.

[0109] Based on this, when the control module receives the attraction instruction, after sending the attraction electric signal to the relay according to the preset attraction time, the control module collects N first capacitor voltages from the compensation capacitor connected with the relay according to the preset frequency, so as to know the attraction of the relay according to the N first capacitor voltages.

[0110] S102, the control module determines the real attraction time of the relay according to the N first capacitor voltages.

[0111] The real attraction time is the time actually used by the relay to complete the attraction mechanical action.

[0112] Since the change trend of the compensation capacitor's capacitor voltage should be relatively gentle before the relay is attracted, and the change trend of the compensation capacitor's capacitor voltage should be consistent with the change trend of the grid voltage after the relay is attracted, the control module can determine the time point at which the relay completes the attraction according to the change of the N first capacitor voltages, and thus can simply and conveniently determine the real attraction duration of the relay.

[0113] The control module can determine the real attraction duration in various ways.

[0114] In some examples, the control module synchronously records the collection time of the first capacitor voltage each time the first capacitor voltage is collected. In the case where the control module starts collecting the first capacitor voltage immediately after sending the attraction electric signal, the control module can determine the real attraction duration as the difference between the collection time of the first capacitor voltage corresponding to the time when the relay is attracted and the collection time of the first first capacitor voltage. In the case where the control module starts collecting the first capacitor voltage after waiting for a minimum attraction duration after sending the attraction electric signal, the control module can first determine the difference between the collection time of the first capacitor voltage corresponding to the time when the relay is attracted and the collection time of the first first capacitor voltage, and then add the minimum attraction duration to the difference to obtain the real attraction duration.

[0115] In other examples, the control module can determine the real attraction duration according to a preset frequency. In the case where the control module starts collecting the first capacitor voltage immediately after sending the attraction electric signal, the control module can determine the real attraction duration as the product of the ranking of the first capacitor voltage corresponding to the time when the relay is attracted in the N first capacitor voltages and a preset period, where the preset period is the inverse of the preset frequency. In the case where the control module starts collecting the first capacitor voltage after waiting for a minimum attraction duration after sending the attraction electric signal, the control module can first determine the product of the ranking of the first capacitor voltage corresponding to the time when the relay is attracted in the N first capacitor voltages and the preset period, and then add the minimum attraction duration to the product to obtain the real attraction duration.

[0116] Taking N as 10 as an example, the control module starts collecting the first capacitor voltage immediately after sending the attraction electric signal, and collects 10 first capacitor voltages, which are distributed as shown in Figure 8 The collection times of the 10 first capacitor voltages are T1 time to T10 time, respectively, as shown in Figure 8 It can be seen that before T6 time, the change trend of the first capacitor voltage corresponding to T1 to T5 time is relatively gentle, and after T6 time, the change trend of the first capacitor voltage corresponding to T7 to T10 time is a sinusoidal curve, which is consistent with the change trend of the grid voltage, so the control module can determine that the relay completes the attraction mechanical action at T6 time, and the real attraction duration is T6-T1.

[0117] S103, the control module determines whether the number of real inductance durations is equal to the preset number.

[0118] When the number of real inductance durations is equal to the preset number, the control module performs S104; when the number of real inductance durations is not equal to the preset number, the control module performs S101 after sending the inductance electric signal to the relay according to the preset inductance duration in the case of receiving the inductance instruction next time.

[0119] When the preset number is 1, the control module determines that one real inductance duration can determine the final inductance duration, which reduces the calculation amount, thereby quickly replacing the preset inductance duration, which helps to improve the control efficiency of the relay inductance.

[0120] When the preset number is greater than 1, the control module can determine the real inductance duration multiple times, and determine the final inductance duration according to the preset number of real inductance durations, thereby improving the accuracy of the determined final inductance duration, and further helping to improve the accuracy of the relay inductance control.

[0121] S104, the control module determines the final inductance duration according to the preset number of real inductance durations.

[0122] When the preset number is 1, the control module directly determines the real inductance duration as the final inductance duration.

[0123] When the preset number is greater than 1, the control module first preprocesses the preset number of real inductance durations, and then determines the final inductance duration according to the preprocessing result, thereby improving the accuracy of determining the final inductance duration.

[0124] The preprocessing can be median processing or mean processing, etc. For example, the control module can determine the average value of the preset number of real inductance durations as the final inductance duration.

[0125] S105, the control module replaces the preset inductance duration with the final inductance duration, and sends the inductance electric signal to the relay according to the replaced preset inductance duration when receiving the inductance instruction next time.

[0126] The final inductance duration can reflect the real duration of the relay to complete the inductance mechanical action, and the control module can replace the preset inductance duration with the final inductance duration after obtaining the final inductance duration, so that the control module sends the inductance electric signal based on the final inductance duration, which can ensure that the relay completes the inductance at the first time point when the relay is expected to induct, avoid the occurrence of impulse inrush current, thereby ensuring the normal operation of the power grid and improving the service life of the relay.

[0127] The control module can periodically execute S101-S105, or the control module can execute S101-S105 when there is a need to adjust the preset closing duration, thereby achieving adaptive adjustment of the preset closing duration.

[0128] In the embodiment of the present application, when the control module receives the closing instruction, the control module collects N first capacitor voltages from the compensation capacitor connected to the relay according to the preset frequency after sending the closing electrical signal to the relay according to the preset closing duration, so as to learn the closing condition of the relay according to the N first capacitor voltages. The control module determines the real closing duration of the relay according to the N first capacitor voltages; the control module repeats the steps of collecting the first capacitor voltage and determining the real closing duration after sending the closing electrical signal to the relay according to the preset closing duration when receiving the closing instruction next time, until a preset number of real closing durations are obtained; the control module determines the final closing duration according to the preset number of real closing durations, thereby improving the accuracy of determining the final closing duration; the control module replaces the preset closing duration with the final closing duration, and sends the closing electrical signal to the relay according to the replaced preset closing duration when receiving the closing instruction next time, which can ensure that the relay completes closing at the first time point when the relay is expected to close, avoid the occurrence of inrush current, thereby ensuring the normal operation of the power grid and improving the service life of the relay.

[0129] Based on the above exemplary description, the control module can determine the real closing duration of the relay by Figure 9 the method shown in the figure.

[0130] Please refer to Figure 9 , Figure 9 a flow chart of a method for determining the real closing duration of a relay provided by an embodiment of the present application. As Figure 9 shown, the method comprises:

[0131] S201, the control module calculates the slopes corresponding to the 2nd first capacitor voltage to the Kth first capacitor voltage in the N first capacitor voltages, to obtain N-2 first slopes.

[0132] Wherein, K is equal to N-1. For example, if the number of first capacitor voltages is 10, then the control module calculates the slopes corresponding to the 2nd first capacitor voltage to the 9th first capacitor voltage, to obtain 8 first slopes.

[0133] Specifically, the control module can calculate the first slope by using the central difference method through the following formula 1.

[0134]

[0135] Wherein, K nKn is the first slope corresponding to the nth first capacitor voltage, n is an integer greater than 1 and less than N, U n+ 1 is the n+1th first capacitor voltage, U n -1 is the n-1th first capacitor voltage, and Δt is a preset period.

[0136] In some examples, the control module can calculate the first slope by using the central difference method according to the following formula 2.

[0137] K n = U n+ 1-U n -1 Formula 2.

[0138] Since the first slope is used in the present application to determine the change of the first capacitor voltage, 2Δt in formula 1 can be set to 1 to obtain formula 2, thereby reducing the calculation complexity without affecting the subsequent comparison results.

[0139] For example, N is 8, and the 8 first capacitor voltages are U1, U2, U3, U4, U5, U6, U7 and U8. The control module calculates the first slope K2 corresponding to U2 according to U1 and U3, calculates the first slope K3 corresponding to U3 according to U2 and U4, and so on, to obtain 6 first slopes K2, K3, K4, K5, K6 and K7.

[0140] S202, the control module finds a second slope greater than a first threshold and less than a second threshold from the N-2 first slopes, and among the N-2 first slopes, there are multiple consecutive first slopes less than or equal to the first threshold before the second slope, and there are multiple consecutive first slopes greater than or equal to the second threshold after the second slope.

[0141] The first threshold is the slope of the curve of the change of the capacitor voltage of the compensation capacitor over time when the compensation capacitor is not put into the power grid.

[0142] The second threshold is the slope of the curve of the change of the capacitor voltage of the compensation capacitor over time when the compensation capacitor is put into the power grid.

[0143] The collection time period of the first capacitor voltage corresponding to the multiple consecutive first slopes less than or equal to the first threshold is the time period when the relay is not attracted, and the collection time period of the first capacitor voltage corresponding to the multiple consecutive first slopes greater than or equal to the second threshold is the time period after the relay is attracted. That is, between the two time periods, the relay is attracted. Based on this, the control module can determine that there is a second slope greater than the first threshold and less than the second threshold between the two time periods, and the control module can determine that the relay is attracted when the first capacitor voltage corresponding to the second slope is collected.

[0144] On the basis of the example of S201, if K2, K3, K4 are less than or equal to the first threshold value, that is, when the first capacitor voltage corresponding to K2, K3, K4 is collected, the relay is not attracted, and K6, K7 are greater than the second threshold value, that is, when the first capacitor voltage corresponding to K6, K7 is collected, the relay is attracted, then the control module determines that K5 is the second slope. Based on this, the control module can know that the relay completes the attraction when the first capacitor voltage corresponding to K5 is collected, that is, the time when the first capacitor voltage corresponding to K5 is collected is the time when the relay completes the attraction mechanical action.

[0145] In addition, if the control module determines that there is no second slope, or that there are multiple slopes between the multiple consecutive first slopes less than or equal to the first threshold value and the multiple consecutive first slopes greater than or equal to the second threshold value, which do not satisfy the condition of being greater than the first threshold value and less than the second threshold value, then the control module can give up this processing, and in the case of receiving the attraction instruction next time, after sending the attraction electric signal to the relay according to the preset attraction time, re-collecting the N first capacitor voltages.

[0146] Based on this, the control module can know the attraction condition of the relay according to the change trend of the first slope, and the control module determines the second slope corresponding to the completion of the attraction of the relay, so as to determine the time length used for the real attraction of the relay.

[0147] S203, the control module determines the first time length according to the second capacitor voltage.

[0148] Among them, the second capacitor voltage is the capacitor voltage corresponding to the second slope in the N first capacitor voltages.

[0149] Among them, the first time length is the time length used by the control module to collect the first capacitor voltage to collect the second capacitor voltage.

[0150] Among them, the control module can determine the first time length in multiple ways.

[0151] In some examples, the control module synchronously records the collection time of the first capacitor voltage each time the first capacitor voltage is collected. The control module can determine the difference between the collection time corresponding to the second capacitor voltage and the collection time corresponding to the first capacitor voltage as the first time length.

[0152] For example, on the basis of the example of S202, K5 is the second slope, U5 is the second capacitor voltage, if the collection time corresponding to U5 is T5, and the collection time corresponding to U1 is T1, then the first time length is T5-T1.

[0153] In some examples, the control module can determine the first time length as a product of the ranking of the second capacitor voltage in the N first capacitor voltages and a preset period, wherein the preset period is an inverse of a preset frequency.

[0154] For example, based on the example of S202, K5 is the second slope, U5 is the second capacitor voltage, and the preset period is Δt, then the first time length is 5Δt.

[0155] S204, the control module determines the real closing time length of the relay according to the first time length.

[0156] In some examples, the control module can execute the step of collecting the N first capacitor voltages from the compensation capacitor according to the preset frequency immediately after sending the closing electrical signal to the relay according to the preset closing time length. In this case, the first time length is the real closing time length.

[0157] In some examples, the control module can execute the step of collecting the N first capacitor voltages from the compensation capacitor according to the preset frequency after a second time length after sending the closing electrical signal to the relay according to the preset closing time length. The second time length is the shortest closing time length of the relay. Since the time length for the relay to complete the closing mechanical action cannot be less than the shortest closing time length, the capacitor voltage of the compensation capacitor in the second time length is certainly slowly decreasing over time, and the control module can collect the capacitor voltage in the time period when the relay can complete the closing mechanical action, thereby reducing the number of collected first capacitor voltages, saving storage space and computing resources. In this case, the real closing time length is the sum of the first time length and the second time length.

[0158] Based on this, since the first slope can reflect the speed and direction of the change of the first capacitor voltage, the control module is more likely to determine the time point when the relay completes closing through the slope, thereby improving the accuracy of determining the real closing time length, and further helping to improve the accuracy of the relay closing control.

[0159] Based on the above exemplary description, in the case where the control module executes the step of collecting the N first capacitor voltages from the compensation capacitor according to the preset frequency after a second time length after sending the closing electrical signal to the relay according to the preset closing time length, the time length used by the control module to collect the N first capacitor voltages is at least the difference between the longest closing time length of the relay and the shortest closing time length of the relay.

[0160] Since the time length for the relay to complete the mechanical action of attraction will not exceed the longest attraction time length, and the control module needs to collect the capacitor voltage when the relay is attracted, the control module needs to collect at least the capacitor voltage at the time when the longest attraction time length elapses when collecting the first capacitor voltage, and based on this, the control module collects the first capacitor voltage for at least the difference time length between the longest attraction time length of the relay and the shortest attraction time length of the relay, thereby improving the accuracy of the determined real attraction time length, and further helping to improve the accuracy of the relay attraction control.

[0161] For example, the longest attraction time length is 6 milliseconds, the shortest attraction time length is 3.5 milliseconds, and the preset frequency is 10 kHz. The control module can start collecting the first capacitor voltage after waiting for 3.5 milliseconds after sending the attraction electric signal, and collect a total of 3 milliseconds to obtain 30 first capacitor voltages.

[0162] Based on the above exemplary description, before the control module determines the first time length according to the second capacitor voltage, the control module can also determine whether the relay is attracted by the following Figure 10 way.

[0163] Please refer to Figure 10 , Figure 10 A method flowchart for determining whether to perform the step of determining the first time length according to the second capacitor voltage is provided for an embodiment of the present application. As Figure 10 shown, the method comprises:

[0164] S301, in the case where the control module receives an attraction instruction, after sending an attraction electric signal to the relay according to a preset attraction time length, the control module collects N first grid voltages from a power grid connected to the relay according to a preset frequency.

[0165] Among them, the N first grid voltages correspond one-to-one to the N first capacitor voltages.

[0166] S302, the control module calculates the slopes corresponding to the 2nd first grid voltage to the Kth first grid voltage in the N first grid voltages, to obtain N-2 third slopes.

[0167] The method for the control module to collect the N first grid voltages is similar to the method for the control module to collect the N first capacitor voltages in S101. The method for the control module to calculate the third slope is similar to the method for the control module to calculate the first slope in S201, which will not be repeated here.

[0168] S303, when the difference between the second slope and the fourth slope is less than or equal to a third threshold value, the control module performs the step of determining the first time length according to the second capacitor voltage.

[0169] The fourth slope is a slope corresponding to the second grid voltage among N-2 third slopes, and the second grid voltage is a voltage corresponding to the second capacitor voltage among N first grid voltages.

[0170] If the relay has been attracted when the second grid voltage / second capacitor voltage is collected, the second grid voltage and the second capacitor voltage should be consistent or close, so the control module can further determine whether the relay is completed to be attracted when the second capacitor voltage is collected according to the difference between the fourth slope corresponding to the second grid voltage and the second slope corresponding to the second capacitor voltage, thereby helping to improve the accuracy of determining the real attraction time.

[0171] Based on the above exemplary description, after the control module sends the attraction electric signal to the relay according to the preset attraction time, the control module can further determine whether to perform the step of collecting N first capacitor voltages in the following Figure 11 manner.

[0172] Please refer to Figure 11 , Figure 11 A method flowchart for determining whether to perform the step of collecting N first capacitor voltages is provided for an embodiment of the present application. As shown in Figure 11 , the method comprises:

[0173] S401, the control module obtains the grid voltage peak of the grid connected with the relay, and collects the third capacitor voltage from the compensation capacitor.

[0174] The grid voltage peak can be pre-stored in the control module, or the control module can also request the grid voltage peak from the reactive power compensation controller or from the grid.

[0175] S402, when the third capacitor voltage is less than or equal to one half of the grid voltage peak, the control module performs the step of collecting N first capacitor voltages from the compensation capacitor according to the preset frequency.

[0176] Since when the residual capacitor voltage of the compensation capacitor is high, the sine wave voltage of the grid voltage is at the peak or the trough, and the slope of the peak and the trough of the sine wave is small, the step of collecting N first capacitor voltages from the compensation capacitor according to the preset frequency can be performed when the third capacitor voltage is less than or equal to one half of the grid voltage peak, so that a more accurate real attraction time can be obtained, thereby improving the accuracy of the relay attraction control.

[0177] In addition, when the third capacitor voltage is greater than one half of the grid voltage peak, the control module can determine again whether to perform the step of collecting N first capacitor voltages from the compensation capacitor according to the preset frequency after the next time the control module sends the attraction electric signal to the relay according to the preset attraction time.

[0178] Exemplarily, the application provides a relay pull-in control device.

[0179] Figure 12 A structural schematic diagram of a relay pull-in control device provided for an embodiment of the application is shown in FIG. 1. Figure 12 As shown in the figure, the device comprises a first acquisition module 101, a first determination module 102, a second determination module 103, a replacement module 104 and a pull-in module 105.

[0180] The first acquisition module 101 is configured to, in the case of receiving a pull-in instruction, acquire N first capacitor voltages from a compensation capacitor connected to the relay according to a preset frequency after sending a pull-in electrical signal to the relay according to a preset pull-in duration, N being a positive integer.

[0181] The first determination module 102 is configured to determine the real pull-in duration of the relay according to the N first capacitor voltages.

[0182] The first acquisition module 101 and the first determination module 102 are configured to, in the case of receiving a pull-in instruction next time, repeatedly perform the steps of acquiring the first capacitor voltages and determining the real pull-in duration after sending a pull-in electrical signal to the relay according to the preset pull-in duration until a preset number of real pull-in durations are obtained.

[0183] The second determination module 103 is configured to determine a final pull-in duration according to the preset number of real pull-in durations.

[0184] The replacement module 104 is configured to replace the preset pull-in duration with the final pull-in duration, and the pull-in module 105 is configured to send a pull-in electrical signal to the relay according to the replaced preset pull-in duration when a pull-in instruction is received next time.

[0185] It should be noted that the relay pull-in control device of the embodiments of the application can be used to execute the technical solutions of the above-mentioned method embodiments, and the implementation principles and technical effects are similar, which will not be described here.

[0186] In some examples, the first determining module 102 is specifically configured to determine N-2 first slopes corresponding to the 2nd first capacitor voltage to the Kth first capacitor voltage in the N first capacitor voltages, K is equal to N-1; find a second slope greater than the first threshold value and less than the second threshold value from the N-2 first slopes, and there are a plurality of continuous first slopes less than or equal to the first threshold value before the second slope and a plurality of continuous first slopes greater than or equal to the second threshold value after the second slope in the N-2 first slopes; determine the first time length according to the second capacitor voltage, the second capacitor voltage is the capacitor voltage corresponding to the second slope in the N first capacitor voltages, and the first time length is the time length for the control module to collect the 1st capacitor voltage to the second capacitor voltage; and determine the real closing time of the relay according to the first time length.

[0187] In some examples, the first collecting module 101 is further configured to, after sending the closing electrical signal to the relay according to the preset closing time length, execute the step of collecting N first capacitor voltages from the compensation capacitor according to the preset frequency after a second time length, and the second time length is the shortest closing time of the relay.

[0188] In some examples, the first determining module 102 is further configured to determine the sum of the first time length and the second time length as the real closing time of the relay.

[0189] In some examples, the device further comprises a second collecting module;

[0190] The second collecting module is configured to, before the control module determines the first time length according to the second capacitor voltage, collect N first grid voltages from a power grid connected to the relay according to a preset frequency after sending a closing electrical signal to the relay according to a preset closing time length in the case of receiving a closing instruction, the N first grid voltages correspond to the N first capacitor voltages one by one; and calculate slopes corresponding to the 2nd first grid voltage to the Kth first grid voltage in the N first grid voltages to obtain N-2 third slopes.

[0191] The first determining module 102 is further configured to, when the difference between the second slope and the fourth slope is less than or equal to a third threshold value, execute the step of determining the first time length according to the second capacitor voltage, the fourth slope is a slope corresponding to the second grid voltage in the N-2 third slopes, and the second grid voltage is a voltage corresponding to the second capacitor voltage in the N first grid voltages.

[0192] In some examples, the device further comprises a third collecting module;

[0193] The third acquisition module is configured to acquire a power grid voltage peak of the power grid connected to the relay after the relay is sent the pull-in electric signal according to the preset pull-in time length, and acquire a third capacitor voltage from the compensation capacitor.

[0194] In some examples, the time length for acquiring the N first capacitor voltages is at least a difference between the longest pull-in time length of the relay and the shortest pull-in time length of the relay.

[0195] Figure 13 A structural schematic diagram of an electronic device is provided for an embodiment of the present application. As shown in the figure, the electronic device can include a first processor 201, and the first processor 201 implements the relay pull-in control method shown in the figure when executing a computer executable program or instruction in a memory. Figure 13 Figures 7 to 11

[0196] The electronic device can be used to execute each step and / or process corresponding to the electronic device in the method embodiment.

[0197] Figure 14 A structural schematic diagram of an electronic device is provided for an embodiment of the present application. As shown in the figure, the electronic device can include a first processor 201, and the first processor 201 implements the relay pull-in control method shown in the figure when executing a computer executable program or instruction in a memory. Figure 14 Figures 7 to 11

[0198] The electronic device can be used to execute each step and / or process corresponding to the electronic device in the method embodiment.

[0199] The electronic device of the present application can be used to execute the technical solutions of the foregoing method embodiments, and the implementation principles and technical effects are similar, wherein the operations implemented by each module can be further referred to the related descriptions of the method embodiments, which will not be described herein. The modules herein can also be replaced by components or circuits.

[0200] The present application can divide the functional modules of the electronic device according to the foregoing method examples, for example, each functional module can be divided corresponding to each function, or two or more functions can be integrated in one processing module. The integrated module can be realized in the form of hardware or in the form of software functional module. It should be noted that the division of modules in each embodiment of the present application is illustrative, and is only a logical function division, and another division mode can be used in actual implementation. ​​​​

[0201] Another embodiment of the present application also provides a computer readable storage medium, and the computer readable storage medium stores a computer program. The computer program is executed by a processor, and the computer program can implement the embodiment of the present application Figures 7 to 11 The relay pull-in control method.

[0202] The present application also provides a program product, which includes execution instructions stored in a computer readable storage medium. At least one processor of an electronic device can read the execution instructions from the computer readable storage medium, and the at least one processor executes the execution instructions to enable the electronic device to implement the embodiment of the present application Figures 7 to 11 The relay pull-in control method.

[0203] The present application also provides a chip, which is connected with a memory or integrates the memory. When a software program stored in the memory is executed, the embodiment of the present application is implemented Figures 7 to 11 The relay pull-in control method.

[0204] In several embodiments provided by the present application, it should be understood that the disclosed system, device and method can be implemented in other manners. For example, the embodiments of the device described above are merely schematic; for example, the division of the modules or units is only a logical function division; there can be another division manner in actual implementation; for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections between different units, can be indirect couplings or communication connections through some interfaces, devices or units, and can be electrical, mechanical or in other forms.

[0205] Those skilled in the art can understand that the combination of features in different embodiments means to be within the scope of the present application and forms different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0206] The above described embodiments are only used to illustrate the technical solutions of the present application, rather than limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalent; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A relay activation control method, characterized in that, Applied to a smart capacitor, the smart capacitor including a control module, a relay, and a compensation capacitor, the method includes: Upon receiving a pull-in command, the control module sends a pull-in electrical signal to the relay according to a preset pull-in duration, and then collects N first capacitor voltages from the compensation capacitor connected to the relay at a preset frequency, where N is a positive integer. The control module determines the actual engagement time of the relay based on the voltages of the N first capacitors; When the control module receives a pull-in command again, it sends the pull-in electrical signal to the relay according to the preset pull-in duration and then repeats the steps of collecting the first capacitor voltage and determining the actual pull-in duration until a preset number of actual pull-in durations are obtained. The control module determines the final engagement time based on the preset number of actual engagement times; The control module replaces the preset engagement time with the final engagement time, and sends an engagement signal to the relay according to the replaced preset engagement time when it receives the engagement command again.

2. The method according to claim 1, characterized in that, The control module determines the actual engagement time of the relay based on the N first capacitor voltages, including: The control module calculates the slopes corresponding to the second to the Kth first capacitor voltages among the N first capacitor voltages, and obtains N-2 first slopes, where K equals N-1. The control module searches for a second slope that is greater than a first threshold and less than a second threshold from the N-2 first slopes. Among the N-2 first slopes, there are multiple consecutive first slopes that are less than or equal to the first threshold before the second slope, and multiple consecutive first slopes that are greater than or equal to the second threshold after the second slope. The control module determines a first duration based on the second capacitor voltage, where the second capacitor voltage is the capacitor voltage among the N first capacitor voltages that corresponds to the second slope, and the first duration is the time taken by the control module from acquiring the first capacitor voltage to acquiring the second capacitor voltage. The control module determines the actual engagement time of the relay based on the first duration.

3. The method according to claim 2, characterized in that, After the control module sends an engagement signal to the relay according to a preset engagement time, it performs the step of collecting N first capacitor voltages from the compensation capacitor according to a preset frequency after a second time. The second time is the shortest engagement time of the relay.

4. The method according to claim 3, characterized in that, The control module determines the actual engagement time of the relay based on the first duration, including: The control module determines the sum of the first duration and the second duration as the actual engagement duration of the relay.

5. The method according to claim 2, characterized in that, Before the control module determines the first duration based on the second capacitor voltage, the method further includes: Upon receiving a pull-in command, the control module sends a pull-in electrical signal to the relay according to a preset pull-in duration, and then collects N first grid voltages from the power grid connected to the relay according to a preset frequency. The N first grid voltages correspond one-to-one with the N first capacitor voltages. The control module calculates the slopes corresponding to the second to the kth first grid voltages among the N first grid voltages, and obtains N-2 third slopes. When the difference between the second slope and the fourth slope is less than or equal to the third threshold, the control module executes the step of determining the first duration based on the second capacitor voltage. The fourth slope is the slope corresponding to the second grid voltage among the N-2 third slopes, and the second grid voltage is the voltage corresponding to the second capacitor voltage among the N first grid voltages.

6. The method according to any one of claims 1 to 5, characterized in that, After sending an engagement signal to the relay according to a preset engagement time, the method further includes: The control module acquires the peak voltage of the power grid connected to the relay and collects the voltage of the third capacitor from the compensation capacitor; When the voltage of the third capacitor is less than or equal to half of the peak value of the grid voltage, the control module performs the step of collecting N first capacitor voltages from the compensation capacitor according to a preset frequency.

7. The method according to claim 3, characterized in that, The time taken to collect the N first capacitor voltages is at least the difference between the longest and shortest activation time of the relay.

8. A smart capacitor, characterized in that, The intelligent capacitor includes: a relay, a compensation capacitor, and a control module for performing the method as described in any one of claims 1-7; The first terminal of the relay is connected to the live wire of the power grid, the second terminal of the relay is connected to the control module, the third terminal of the relay is connected to the first terminal of the compensation capacitor, the second terminal of the compensation capacitor is connected to the neutral wire of the power grid, the second terminal of the control module is connected between the live wire of the power grid and the first terminal of the relay, and the third terminal of the control module is connected between the third terminal of the relay and the first terminal of the compensation capacitor.

9. A reactive power compensation system, characterized in that, The reactive power compensation system includes: a power grid, a reactive power compensation controller, and at least three smart capacitors as described in claim 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer-executable program or instructions, the computer-executable program or instructions being configured to perform the relay engagement control method according to any one of claims 1-7.

Images