A method, system and apparatus for adaptive control of a latching relay

Abstract

The application provides a method, system and device for adaptively controlling a magnetic latching relay, and relates to the field of relay control. The method comprises the following steps: from a first time point, a target phase electric capacity current of the magnetic latching relay is sampled at a set sampling frequency; when the target sampling point capacity current value obtained by the first sampling is less than a set threshold, the first sampling is stopped; a product of the sampling frequency and the sampling number of the first sampling is calculated to obtain a first time length; a predicted time point of the current zero point of the target phase electric in a working period is determined; the predicted time point is subtracted by the first time length to obtain a second time point; the second time point is subtracted by a second time length to obtain a third time point; and a tripping control instruction is sent to the magnetic latching relay at the third time point. In this way, the magnetic latching relay can be adaptively tripped at the mechanical action time of the capacity current zero point as the service life of the magnetic latching relay is prolonged.

Description

Technical Field

[0001] This application relates to the field of relay control technology, and in particular to a method, system and device for adaptive control of a magnetic latching relay. Background Technology

[0002] Currently, in the process of reactive power compensation of intelligent capacitors, it is necessary to ensure that the magnetic latching relay completes the mechanical action from sending the control command from the control device to the relay completing the command operation at the moment when the capacitor current is zero. Therefore, it is necessary to determine the moment when the control device sends the control command based on the mechanical action time when the current is zero. Otherwise, when the magnetic latching relay is hard-cut, the arcing damages the magnetic latching relay contacts, causing them to stick and fail to disconnect.

[0003] However, during the use of current magnetic latching relays, as the service life (number of times it is engaged) increases, the mechanical action time of the relay will change. This makes it impossible for the magnetic latching relay to complete the mechanical action accurately at the zero point of the capacitor current. As a result, the magnetic latching relay will engage when the capacitor current value is high, which may cause the relay contacts to burn and prevent the relay from disconnecting. This seriously affects the normal operation and service life of the relay. Summary of the Invention

[0004] In view of this, embodiments of this application provide a method, system, and device for adaptively controlling a magnetic latching relay, which aims to enable the magnetic latching relay to adaptively cut off the mechanical action time at the zero point of the capacitor current.

[0005] In a first aspect, embodiments of this application provide a method for adaptively controlling a magnetic latching relay, the method comprising:

[0006] Starting from a first time point, the capacitive current of the target phase of the magnetic latching relay is sampled at a set sampling frequency. When the capacitive current value of the target sampling point obtained by the first sampling is less than a set threshold, the first sampling is stopped. The first time point is the time point when the phase sends a cut-off control command to the magnetic latching relay within the current prediction period. The target phase is one of the phases of the AC power transmitted through the magnetic latching relay.

[0007] The first time length is obtained by multiplying the number of samples in the first sample by the sampling frequency.

[0008] The predicted time point of the zero current of the target phase current within the working cycle is determined. The working cycle is the cycle after the predicted cycle. The working cycle and the predicted cycle are divided according to the capacitive current value of the phase current. The predicted time point of the zero current is the point within the working cycle that is a target time length away from the start time of the working cycle. The capacitive current value at the predicted time point is less than a set threshold.

[0009] Subtract the first time length from the predicted time point to obtain the second time point;

[0010] Subtract the second time length from the second time point to obtain the third time point;

[0011] At the third time point, a cut-off control command is sent to the magnetic latching relay to control the time for the magnetic latching relay to complete the mechanical action of cutting off the current zero point in the working cycle.

[0012] Optionally, the method for obtaining the target time length includes:

[0013] During the initial period of the phase current, the capacitive current of the target phase current of the magnetic latching relay is sampled a second time at a set sampling frequency to obtain multiple second sampling points; the sampling frequency of the second sampling is an integer multiple of the voltage frequency of the target phase current.

[0014] The second sampling point with the smallest capacitive current value among the second sampling points is set as the current zero point in the initial period, and the capacitive current value of the current zero point is less than a set threshold.

[0015] The time length between the start time and the current zero point within the initial period is taken as the target time length.

[0016] Optionally, the method further includes:

[0017] The sampling is performed a first number of times, starting from the current zero point position of the initial period, at the sampling frequency of the second sampling; the first number of times is the sampling frequency of the second sampling divided by a multiple of the voltage frequency of the target phase current;

[0018] Obtain the capacitor current value at the end of the first number of sampling times;

[0019] If the capacitor current value is less than the set threshold, then the target time length is accurate.

[0020] Optionally, in the second period in chronological order, the method for obtaining the first time length includes:

[0021] The actual measurement of the time required for the magnetic latching relay to cut off the mechanical action, or the time required for the magnetic latching relay to cut off the mechanical action provided by the manufacturer.

[0022] Optionally, when there are multiple prediction periods, calculating the product of the number of samples of the first sample and the sampling frequency of the first sample to obtain the first time length includes:

[0023] After removing the maximum and minimum number of sampling times of the first sample within multiple prediction periods, calculate the average number of the remaining multiple first sample times;

[0024] The first time length is obtained by multiplying the average number of times by the sampling frequency of the first sample.

[0025] Optionally, the sampling frequency of the first sample is the same as the sampling frequency of the second sample.

[0026] Optional components include: a driver, a magnetic latching relay, a current transformer, a compensation capacitor, and control equipment;

[0027] Both the control device and the magnetic latching relay are powered by AC power from the mains.

[0028] The analog-to-digital converter port of the control device is connected to the output terminal of the current transformer; the output terminal of the control device is connected to the input terminal of the driver; the output terminal of the driver is connected to the input terminal of the magnetic latching relay; the magnetic latching relay is connected to the current transformer; the current transformer is connected to the compensation capacitor; and the compensation capacitor is connected to the neutral line of the AC power grid.

[0029] The current transformer is used to obtain the capacitive current value of the target sampling point and send the capacitive current value of the target sampling point to the magnetic latching relay;

[0030] The control device is used to acquire the capacitive current value of the target sampling point, and to perform a first sampling of the capacitive current of the target phase of the magnetic latching relay at a set sampling frequency starting from a first time point. When the capacitive current value of the target sampling point obtained by the first sampling is less than a set threshold, the first sampling is stopped. The first time point is the time point at which the phase sends a cut-off control command to the magnetic latching relay within the current prediction cycle. The target phase is one phase of the AC power transmitted through the magnetic latching relay. The first time length is obtained by calculating the product of the number of samplings of the first sampling and the sampling frequency. The zero point of the current of the target phase within the working cycle is determined. The predicted time point is defined as follows: the working cycle is the cycle following the predicted cycle, and the working cycle and the predicted cycle are divided based on the capacitance current value of the phase current; the predicted time point is subtracted from the first time length to obtain the second time point; the current zero point is the point within the working cycle that is a target time length away from the start time of the working cycle, and the capacitance current value at the predicted time point is less than a set threshold; the second time point is subtracted from the second time point to obtain the third time point; at the third time point, a cut-off control command is sent to the magnetic latching relay to control the time for the magnetic latching relay to complete the current zero point cut-off mechanical action in the working cycle;

[0031] The driver is used to amplify the cut-off control command and send the amplified cut-off control command to the magnetic latching relay;

[0032] The magnetic latching relay is used to perform a zero-current cut-off mechanical action time after receiving the amplified cut-off control command.

[0033] Optionally, the current transformer is further configured to acquire the capacitive current value at the second sampling point and send the capacitive current value at the second sampling point to the magnetic latching relay;

[0034] The control device is further configured to acquire the capacitive current value of the second sampling point, and within the initial period of the phase current, to perform a second sampling on the capacitive current of the target phase current of the magnetic latching relay at a set sampling frequency to obtain multiple second sampling points; the sampling frequency of the second sampling is an integer multiple of the voltage frequency of the target phase current; the second sampling point with the smallest capacitive current value among the second sampling points is set as the current zero point within the initial period, and the capacitive current value of the current zero point is less than a set threshold; the time length between the start time of the initial period and the time of the current zero point is taken as the target time length.

[0035] Secondly, embodiments of this application provide a system for controlling a magnetic latching relay, the device comprising:

[0036] The control device is further configured to perform a first number of samplings starting from the current zero point position of the initial period at a second sampling frequency; the first number of samplings is a multiple of the second sampling frequency divided by the voltage frequency of the target phase current;

[0037] Obtain the capacitor current value at the end of the first number of sampling times;

[0038] If the capacitor current value is less than the set threshold, then the target time length is accurate.

[0039] Thirdly, this application also proposes an adaptive control magnetic latching relay device, including a processor and a memory, wherein the memory is used to store code or a program, and the processor is used to call the code or program to implement the above-described adaptive control magnetic latching relay method.

[0040] This application provides a method, system, and device for adaptively controlling a magnetic latching relay. Starting from the moment a cut-off control command is issued to the magnetic latching relay, the capacitive current of each phase of the relay is sampled at a set sampling frequency. When the capacitive current value at the target sampling point obtained by the first sampling is less than a set threshold, the first sampling is stopped. The time length used to execute the cut-off control command is determined based on the product of the number of samplings at the first sampling point and the sampling frequency. In subsequent work cycles, this time length can be adaptively subtracted from the current zero point within that work cycle to obtain a third moment for sending the cut-off control command to the magnetic latching relay, thus adaptively controlling the magnetic latching relay to complete the current zero-point cut-off in the work cycle. The time length used to execute the cut-off control command is adaptively updated based on the sampling in the current cycle, ensuring that the magnetic latching relay can achieve the mechanical action time of zero capacitive current cut-off in the next cycle. In this way, even with the extended service life of the magnetic latching relay, the adaptive mechanical action time of zero capacitive current cut-off can still be guaranteed. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in this embodiment or the prior art, the drawings used in the description of the embodiment or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This application provides a schematic flowchart of a method for adaptively controlling a magnetic latching relay.

[0043] Figure 2 This is a schematic diagram illustrating that the prediction period length is an integer multiple of the sampling period length, as provided in the embodiments of this application.

[0044] Figure 3 A schematic diagram of the working cycle provided in the embodiments of this application;

[0045] Figure 4 This application provides a schematic diagram for confirming zero current point in an embodiment.

[0046] Figure 5 This is a schematic diagram of the system structure of an adaptive control magnetic latching relay provided in an embodiment of this application. Detailed Implementation

[0047] Traditional relays immediately perform the disconnection task upon receiving a switching command. However, this may coincide with the period of maximum voltage or maximum capacitive current across the relay. This can lead to relay arcing, and in more serious cases, the relay contacts may burn, preventing the relay from disconnecting altogether. This severely impacts the relay's normal operation and lifespan. Currently, in reactive power compensation using intelligent capacitors, the magnetic latching relay is typically designed to disconnect at the point where the capacitive current is zero. Otherwise, arcing during hard-point disconnection damages the silver contacts of the magnetic latching relay, causing them to stick and fail to disconnect. However, with the increasing lifespan (number of activations) of current magnetic latching relays, their engagement time may change, potentially preventing them from disconnecting at the point where the capacitive current is zero.

[0048] Based on the above reasons, this application, starting from the moment the cut-off control command is issued to the magnetically latched relay, first samples the capacitive current of each phase of the magnetically latched relay at a set sampling frequency. When the capacitive current value of the target sampling point obtained in the first sampling is less than a set threshold, the first sampling stops. The time length used to execute the cut-off control command is determined based on the product of the number of samples at the first sampling point and the sampling frequency. In subsequent work cycles, this time length can be subtracted from the moment of current zero point within that work cycle to obtain the third moment when the cut-off control command is sent to the magnetically latched relay, thereby controlling the magnetically latched relay to complete the current zero point cut-off in that work cycle. The first sampling is performed on the prediction cycle, and the time length used to execute the cut-off control command is calculated. Then, the predicted moment of current zero point in subsequent work cycles is calculated, and the first time length is subtracted to adaptively obtain the moment when the cut-off control command is issued for the work cycle. In this way, as the service life of the magnetic latching relay is extended, the first time length can be calculated based on the first sample within the current prediction cycle, and then the moment for issuing the cut-off control command in the next working cycle can be adaptively determined. This ensures that the magnetic latching relay can still adaptively update the first time length after executing commands multiple times, and determine the mechanical action time for zero-point cut-off of capacitor current.

[0049] The components that can be used to implement the following embodiments include: control devices, drivers, magnetic latching relays, current transformers, and compensation capacitors.

[0050] Both the control device and the magnetic latching relay are powered by three-phase AC power, which can be State Grid AC power; the control device can be a microcontroller capable of programming control; the control device is connected to the magnetic latching relay through a driver and sends control commands to the magnetic latching relay.

[0051] The magnetic latching relay is connected to the compensation capacitor through a current transformer, and sends the sampled capacitor current value to the control device through the current transformer.

[0052] Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0053] See Figure 1 , Figure 1 A flowchart illustrating an adaptive control magnetic latching relay method provided in this application includes:

[0054] S101. Starting from a first time point, perform a first sampling of the capacitive current of the target phase of the magnetic latching relay at a set sampling frequency. When the capacitive current value of the target sampling point obtained by the first sampling is less than a set threshold, stop the first sampling. The first time point is the time point at which the phase sends a cut-off control command to the magnetic latching relay within the current prediction period.

[0055] The target phase current is one of the phase currents in the alternating current transmitted through the magnetic latching relay.

[0056] The first time point is the moment when the cut-off control command is sent to the magnetic latching relay during the current prediction cycle.

[0057] The set sampling frequency is an integer multiple of the voltage frequency of the AC power supply for the magnetic latching relay. The AC power supply for the magnetic latching relay can be State Grid AC power with a voltage frequency of 50 Hz, then the AC power period is 20 milliseconds. Figure 2 A diagram illustrating that the prediction period length is an integer multiple of the sampling period length is provided. (See attached diagram.) Figure 2 As shown, the first sampling is performed within a prediction period of 20 milliseconds for the current AC power, at a set sampling frequency, to sample the capacitive current value of the magnetic latching relay that transmits the target phase current. The prediction period of 20 milliseconds is an integer multiple of the sampling period T.

[0058] The target sampling point is the sampling point where the capacitor current value is less than the set threshold. It is also the point at which the magnetic latching relay cuts off the mechanical action time. When the magnetic latching relay performs the action at this point, it can avoid the problem of arcing damage to the silver point of the magnetic latching relay during hard point cut-off, which would lead to adhesion and failure to disconnect.

[0059] S102. Calculate the product of the number of samplings of the first sample and the sampling frequency to obtain the first time length.

[0060] The first sampling number is the number of times the sample is taken between the first time point of the current period and the target sampling point of the current period at a set sampling frequency.

[0061] Calculating the product of the number of samples taken in the first sampling and the sampling frequency is to calculate the time length between the first time point of the current cycle and the time point of the target sampling point of the current cycle, and to determine the first time length of the mechanical action time to be removed in the current cycle.

[0062] S103. Determine the predicted time point of the zero current of the target phase current within the working cycle. The working cycle is the cycle after the predicted cycle. The working cycle and the predicted cycle are divided according to the capacitance current value of the phase current. The predicted time point of the zero current is the point within the working cycle that is a distance from the target time length of the start time of the working cycle. The capacitance current value at the predicted time point is less than a set threshold.

[0063] The current zero point can be the point at which the capacitive current, determined during the initial cycle of the target phase current, falls below a set threshold.

[0064] The target time length can be the time length between the zero point of the current and the start time of the initial period in the initial period, which is the period before the predicted period.

[0065] The method for determining the predicted time point of the current zero point within the working cycle can be the time point determined by adding the time length of all cycles between the start time of the working cycle and the start time of the initial cycle to the target time length.

[0066] S104. Subtract the first time length from the predicted time point to obtain the second time point.

[0067] S105. Subtract the second time length from the second time point to obtain the third time point.

[0068] The second time length is a manually set time length, which is a period of time earlier than the second time point. This is because the current zero point is a point within a range of less than the threshold. In order to avoid the time point of cutting off the mechanical action crossing the zero current point, the arc will be extinguished at the next zero point after crossing the zero, which means that the arc may last for half a cycle, causing serious damage to the relay hard point.

[0069] S106. At the third time point, a cut-off control command is sent to the magnetic latching relay to control the time for the magnetic latching relay to complete the mechanical action of cutting off the current zero point in the working cycle.

[0070] As can be seen from steps S101-S106 above, with the extension of the magnetic latching relay's service life, the first time length can also be calculated based on the first sample within the current prediction period, and thus refer to... Figure 3 The schematic diagram of the working cycle provided in this application embodiment shows that in the working cycle, the third time point is determined by subtracting the sum of the first time length and the second time length from the predicted time point of the current zero point. The first time length can be calculated by using the cycle in which the most recently sent cut-off control command is sent as the prediction cycle at any time, and the time when the cut-off control command is issued in the current working cycle can be adaptively determined, thereby ensuring that the magnetic latching relay adaptively cuts off the mechanical action time at the zero point of the capacitor current.

[0071] In the embodiments of this application, the above Figure 1 There are several possible implementations for obtaining the first time length in step S102, which will be described below. It should be noted that the implementations given below are only illustrative examples and do not represent all implementations of the embodiments of this application.

[0072] In the first possible implementation, the method for obtaining the first time length in the second cycle in chronological order may further include: measuring the time length required for the magnetic latching relay to cut off the mechanical action, or, based on the time length provided by the manufacturer for the magnetic latching relay to cut off the mechanical action.

[0073] Based on the first possible implementation, when it is necessary to calculate the second time point using the first time length, the setting can be made using actual measurements or factory data. The first cycle before the second cycle is used to obtain the target time length for determining the current zero point.

[0074] In a second possible implementation, when there are multiple prediction periods, calculating the product of the number of samples of the first sample and the sampling frequency of the first sample to obtain the first time length includes:

[0075] After removing the maximum and minimum number of samplings of the first sample within multiple prediction periods, calculate the average number of the remaining multiple first samples; calculate the product of the average number and the sampling frequency of the first sample to obtain the first time length.

[0076] According to the second possible implementation method, the number of samplings for multiple prediction cycles before the working cycle can be obtained, the highest and lowest number of samplings can be excluded, the average of the remaining samplings can be calculated, outliers can be reduced, and a more accurate first time length value can be obtained.

[0077] In the embodiments of this application, the above Figure 1The method for obtaining the target time length in step S103 has possible implementations, which are described below. It should be noted that the implementations given below are merely illustrative examples and do not represent all implementations of the embodiments of this application.

[0078] A1. During the initial period of the phase current, the capacitive current of the target phase current of the magnetic latching relay is sampled a second time at a set sampling frequency to obtain multiple second sampling points; the sampling frequency of the second sampling is an integer multiple of the voltage frequency of the target phase current.

[0079] The initial period is before the prediction period, and the sampling frequency of the second sample can be the same as that of the first sample.

[0080] A2. The second sampling point with the smallest capacitance current value among the second sampling points is set as the current zero point in the initial period, and the capacitance current value of the current zero point is less than a set threshold.

[0081] By performing a second sampling at a certain sampling frequency, there is a certain time interval between the two sampling points. Therefore, by selecting the second sampling point where the capacitor current value is less than the set threshold, it is considered as the zero point of the current and is also used as the zero point of the current in the initial period.

[0082] A3. The time length between the start time and the current zero point within the initial period is taken as the target time length.

[0083] According to steps A1-A3 above, the second sampling point where the capacitor current value is less than the set threshold is taken as the current zero point in the initial cycle. The time length between the time point of the current zero point and the start time of the initial cycle is taken as the target time length. Since the voltage frequency of the target phase power is constant (the State Grid voltage frequency is 50 Hz), the time interval between the time point of the current zero point and the start time of the cycle containing the current zero point in each cycle of the target phase power is constant, and is the target time length. See [link to relevant documentation]. Figure 4 This is a schematic diagram for confirming the zero point of current provided in an embodiment of this application, which determines the target time length in the initial period.

[0084] Following step A3 above, to further ensure the correctness of the target time length, there is another possible implementation method, which includes:

[0085] B1. Starting from the current zero point position of the initial period, perform a first number of samplings at the sampling frequency of the second sampling; the first number of samplings is a multiple of the sampling frequency of the second sampling divided by the voltage frequency of the target phase.

[0086] B2. Obtain the capacitor current value at the end of the first number of sampling times.

[0087] B3. If the capacitor current value is less than the set threshold, then the target time length is accurate.

[0088] According to steps B1-B3, see [link / reference] Figure 4 This is a schematic diagram of current zero-point confirmation provided in an embodiment of this application. After performing a first number of samplings at the second sampling frequency, an initial period (20 milliseconds) of sampling is performed. If the capacitor current value at the end of the first number of samplings is less than a set threshold, the position of the capacitor current zero point is confirmed to be accurate, and the target time length obtained within the initial period is accurate.

[0089] The above are some specific implementations of an adaptive control magnetic latching relay method provided in this application. Based on this, this application also provides a corresponding system.

[0090] See Figure 5 The diagram shows a system schematic of an adaptive control magnetic latching relay. The system includes a driver, a magnetic latching relay, a current transformer, a compensation capacitor, and a control device.

[0091] Both the control device and the magnetic latching relay are powered by AC power from the mains.

[0092] The analog-to-digital converter port of the control device is connected to the output terminal of the current transformer; the output terminal of the control device is connected to the input terminal of the driver; the output terminal of the driver is connected to the input terminal of the magnetic latching relay; the magnetic latching relay is connected to the current transformer; the current transformer is connected to the compensation capacitor; and the compensation capacitor is connected to the neutral line of the AC power grid.

[0093] The current transformer is used to obtain the capacitive current value of the target sampling point and send the capacitive current value of the target sampling point to the magnetic latching relay;

[0094] The control device is used to acquire the capacitive current value of the target sampling point, and to perform a first sampling of the capacitive current of the target phase of the magnetic latching relay at a set sampling frequency starting from a first time point. When the capacitive current value of the target sampling point obtained by the first sampling is less than a set threshold, the first sampling is stopped. The first time point is the time point at which the phase sends a cut-off control command to the magnetic latching relay within the current prediction cycle. The target phase is one phase of the AC power transmitted through the magnetic latching relay. The first time length is obtained by calculating the product of the number of samplings of the first sampling and the sampling frequency. The zero point of the current of the target phase within the working cycle is determined. The predicted time point is defined as follows: the working cycle is the cycle following the predicted cycle, and the working cycle and the predicted cycle are divided based on the capacitance current value of the phase current; the predicted time point is subtracted from the first time length to obtain the second time point; the current zero point is the point within the working cycle that is a target time length away from the start time of the working cycle, and the capacitance current value at the predicted time point is less than a set threshold; the second time point is subtracted from the second time point to obtain the third time point; at the third time point, a cut-off control command is sent to the magnetic latching relay to control the time for the magnetic latching relay to complete the current zero point cut-off mechanical action in the working cycle.

[0095] The driver is used to amplify the cut-off control command and send the amplified cut-off control command to the magnetic latching relay.

[0096] The magnetic latching relay is used to perform a zero-current cut-off mechanical action time after receiving the amplified cut-off control command.

[0097] As can be seen from the above system, the control device obtains the capacitive current value of the sampling point of the magnetic latching relay transmitting the target phase electricity through the current transformer. As the service life of the magnetic latching relay is extended, it can also calculate the first time length based on the first sampling in one or more prediction cycles, and then determine the time when to issue the cut-off control command in the subsequent working cycle. This ensures that the magnetic latching relay adaptively cuts off the mechanical action time at the zero point of the capacitive current, reduces the relay arcing when the capacitor is cut off, and extends the service life.

[0098] In one possible implementation, the current transformer is further configured to acquire the capacitive current value of the second sampling point and send the capacitive current value of the second sampling point to the magnetic latching relay.

[0099] The control device is further configured to acquire the capacitive current value of the second sampling point, and within the initial period of the phase current, to perform a second sampling on the capacitive current of the target phase current of the magnetic latching relay at a set sampling frequency to obtain multiple second sampling points; the second sampling frequency is an integer multiple of the voltage frequency of the target phase current; the second sampling point with the smallest capacitive current value among the second sampling points is set as the current zero point within the initial period, and the capacitive current value of the current zero point is less than a set threshold; the time length between the start time of the initial period and the time of the current zero point is taken as the target time length.

[0100] In another possible implementation, the control device is further configured to perform a first number of samplings starting from the current zero point position of the initial period at a second sampling frequency; the first number of samplings is a multiple of the second sampling frequency divided by the voltage frequency of the target phase current; obtain the capacitor current value at the end of the first number of samplings; if the capacitor current value is less than a set threshold, the target time length is accurate.

[0101] This application also provides corresponding devices and computer storage media for implementing the solutions provided in this application.

[0102] The device includes a memory and a processor. The memory stores instructions or code, and the processor executes the instructions or code to enable the device to perform an adaptive control magnetic latching relay method according to any embodiment of this application.

[0103] The computer storage medium stores code, and when the code is executed, the device running the code implements a method for adaptive control of a magnetic latching relay as described in any embodiment of this application.

[0104] In the embodiments of this application, the terms "first" and "second" (if they exist) are used only as name identifiers and do not represent the order of first and second.

[0105] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that all or part of the steps in the methods of the above embodiments can be implemented by means of software plus a general-purpose hardware platform. Based on this understanding, the technical solution of this application can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as a read-only memory (ROM) / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, a server, or a network communication device such as a router) to execute the methods described in the various embodiments of this application or some parts of the embodiments.

[0106] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0107] The above description is merely an exemplary implementation of this application and is not intended to limit the scope of protection of this application.

Claims

1. A method for adaptively controlling a magnetic latching relay, characterized in that, The method includes: Starting from a first time point, the capacitive current of the target phase of the magnetic latching relay is sampled at a set sampling frequency. When the capacitive current value of the target sampling point obtained by the first sampling is less than a set threshold, the first sampling is stopped. The first time point is the time point at which the target phase sends a cut-off control command to the magnetic latching relay within the current prediction period. The target phase is one phase of the AC power transmitted through the magnetic latching relay. The first time length is obtained by multiplying the number of samples in the first sample by the sampling frequency. The predicted time point of the zero current of the target phase current within the working cycle is determined. The working cycle is the cycle after the predicted cycle. The working cycle and the predicted cycle are divided according to the capacitive current value of the target phase current. The predicted time point of the zero current is the point within the working cycle that is a target time length away from the start time of the working cycle. The capacitive current value at the predicted time point is less than a set threshold. Subtract the first time length from the predicted time point to obtain the second time point; Subtract the second time length from the second time point to obtain the third time point; At the third time point, a cut-off control command is sent to the magnetic latching relay to control the time for the magnetic latching relay to complete the mechanical action of cutting off the current zero point in the working cycle.

2. The method according to claim 1, characterized in that, The method for obtaining the target time length includes: During the initial period of the target phase current, the capacitive current of the target phase current of the magnetic latching relay is sampled a second time at a set sampling frequency to obtain multiple second sampling points; the sampling frequency of the second sampling is an integer multiple of the voltage frequency of the target phase current. The second sampling point with the smallest capacitive current value among the second sampling points is set as the current zero point in the initial period, and the capacitive current value of the current zero point is less than a set threshold. The time length between the start time and the current zero point within the initial period is taken as the target time length.

3. The method according to claim 2, characterized in that, The method further includes: The sampling is performed a first number of times, starting from the current zero point position of the initial period, at the sampling frequency of the second sampling; the first number of times is a multiple of the sampling frequency of the second sampling divided by the voltage frequency of the target phase current. Obtain the capacitor current value at the end of the first number of sampling times; If the capacitor current value is less than the set threshold, then the target time length is accurate.

4. The method according to claim 1, characterized in that, In the second period in chronological order, the methods for obtaining the first time length include: The actual measurement of the time required for the magnetic latching relay to cut off the mechanical action, or the time required for the magnetic latching relay to cut off the mechanical action provided by the manufacturer.

5. The method according to claim 1, characterized in that, When there are multiple prediction periods, calculating the product of the number of samples of the first sample and the sampling frequency of the first sample to obtain the first time length includes: After removing the maximum and minimum number of sampling times of the first sample within multiple prediction periods, calculate the average number of the remaining multiple first sample times; The first time length is obtained by multiplying the average number of times by the sampling frequency of the first sample.

6. The method according to claim 2, characterized in that, The sampling frequency of the first sample is the same as that of the second sample.

7. A system for adaptively controlling a magnetic latching relay, characterized in that, include: Drivers, magnetic latching relays, current transformers, compensation capacitors, and control devices; Both the control device and the magnetic latching relay are powered by AC power from the mains. The analog-to-digital converter port of the control device is connected to the output terminal of the current transformer; the output terminal of the control device is connected to the input terminal of the driver; the output terminal of the driver is connected to the input terminal of the magnetic latching relay; the magnetic latching relay is connected to the current transformer; the current transformer is connected to the compensation capacitor; and the compensation capacitor is connected to the neutral line of the AC power grid. The current transformer is used to obtain the capacitive current value of the target sampling point and send the capacitive current value of the target sampling point to the magnetic latching relay; The control device is used to acquire the capacitive current value of the target sampling point, and to perform a first sampling on the capacitive current of the target phase of the magnetic latching relay at a set sampling frequency starting from a first time point. When the capacitive current value of the target sampling point obtained by the first sampling is less than a set threshold, the first sampling is stopped. The first time point is the time point at which the target phase current sends a cut-off control command to the magnetic latching relay within the current prediction cycle; The target phase current is one phase current in the alternating current transmitted through the magnetic latching relay; the first time length is obtained by calculating the product of the number of samplings of the first sampling and the sampling frequency; The predicted time point of the current zero point of the target phase current within the working cycle is determined. The working cycle is the cycle following the predicted cycle, and the working cycle and the predicted cycle are divided based on the capacitive current value of the target phase current. The predicted time point is subtracted from the first time length to obtain the second time point. The current zero point is the point within the working cycle that is a target time length away from the start time of the working cycle, and the capacitive current value at the predicted time point is less than a set threshold. The second time point is subtracted from the second time length to obtain the third time point. At the third time point, a cut-off control command is sent to the magnetic latching relay to control the time for the magnetic latching relay to complete the mechanical action of current zero point cut-off within the working cycle. The driver is used to amplify the cut-off control command and send the amplified cut-off control command to the magnetic latching relay; The magnetic latching relay is used to perform a zero-current cut-off mechanical action time after receiving the amplified cut-off control command.

8. The system according to claim 7, characterized in that, The current transformer is also used to obtain the capacitive current value of the second sampling point and send the capacitive current value of the second sampling point to the magnetic latching relay; The control device is further configured to acquire the capacitive current value of the second sampling point, and within the initial period of the target phase current, to perform a second sampling on the capacitive current of the magnetic latching relay at a set sampling frequency to obtain multiple second sampling points; the sampling frequency of the second sampling is an integer multiple of the voltage frequency of the target phase current; The second sampling point with the smallest capacitance current value among the second sampling points is set as the current zero point in the initial period, and the capacitance current value of the current zero point is less than a set threshold; the time length between the start time of the initial period and the time of the current zero point is taken as the target time length.

9. The system according to claim 8, characterized in that, The control device is further configured to perform a first number of samplings starting from the current zero point position of the initial period at a second sampling frequency; the first number of samplings is a multiple of the second sampling frequency divided by the voltage frequency of the target phase current; Obtain the capacitor current value at the end of the first number of sampling times; If the capacitor current value is less than the set threshold, then the target time length is accurate.

10. A device for adaptively controlling a magnetic latching relay, characterized in that, It includes a processor and a memory, the memory being used to store code or a program, and the processor being used to invoke the code or program to implement the method for adaptive control of a magnetic latching relay as described in any one of claims 1-6.

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