Relay adhesion detection method, device, equipment, storage medium and program product in grid-connected power system

Abstract

The present application relates to a relay adhesion detection method, device, equipment, storage medium and program product. The method includes: adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency, and obtaining multiple voltage data under the second inverter voltage frequency, determining a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data, and determining the relay adhesion detection result according to the comparison value and the reference value, thereby realizing the detection of whether the relay in the grid-connected power system has a adhesion fault.

Description

Technical Field

[0001] The present application relates to the technical field of power systems, and in particular to a relay adhesion detection method, device, equipment, storage medium and program product. Background Art

[0002] In the field of single-phase grid-connected or three-phase grid-connected power systems, a relay is set between the AC grid and the inverter to detect faults on the grid and isolate them in time to reduce the impact of the faults on the entire grid. However, as the relay is used for a long time and is affected by the application environment, the relay may have a sticking failure, that is, the contacts of the relay cannot be opened or closed normally. If the relay has a sticking failure, the inverter cannot be effectively disconnected from the grid, and the subsequent inverter cannot be effectively connected to the grid.

[0003] Therefore, how to detect whether a relay in a grid-connected power system has a sticking fault has become a technical problem that needs to be solved urgently in the field. Summary of the invention

[0004] Based on this, it is necessary to provide a relay adhesion detection method, device, equipment, storage medium and program product that can detect whether a relay in a grid-connected power system has a adhesion fault in order to address the above technical problems.

[0005] In a first aspect, the present application provides a relay adhesion detection method, comprising:

[0006] Adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0007] Acquire a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter;

[0008] Determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data;

[0009] The relay sticking detection result is determined based on the comparison value and the reference value.

[0010] In one embodiment, determining a relay sticking detection result according to a comparison value and a reference value includes:

[0011] If the comparison value is greater than the reference value, the relay non-sticking is taken as the relay sticking detection result;

[0012] If the comparison value is not greater than the reference value, the relay sticking is regarded as the relay sticking detection result.

[0013] In one embodiment, determining the comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data includes:

[0014] Determine the absolute value of the difference between the grid voltage and the inverter voltage in each voltage data;

[0015] The average of the absolute values ​​is determined and used as the comparison value.

[0016] In one embodiment, the method further comprises:

[0017] Determining a reference value using an objective function based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and a preset disturbance frequency;

[0018] Among them, the objective function is:

[0019] ;

[0020] is the preset rated voltage peak value, is the first inverter voltage frequency, is the preset sampling period, is the preset disturbance frequency, , is the number of sampling times of the voltage of the inverter in one inversion cycle of the inverter, is greater than or equal to 1 and less than or equal to integer, A time multiple.

[0021] In one embodiment, based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and a preset disturbance frequency, a reference value is determined using an objective function, including:

[0022] Determining a target curve corresponding to the target function based on the first inverter voltage frequency, a preset rated voltage peak, a preset sampling period, and a preset disturbance frequency;

[0023] Use the minimum value on the target curve as the reference value.

[0024] In one embodiment, the method further comprises:

[0025] Obtaining a first function and a second function; the first function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a first inverter voltage frequency, and the second function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a second inverter voltage frequency;

[0026] Determining a target function based on the first function and the second function;

[0027] Among them, the first function is: , the second function is .

[0028] In a second aspect, the present application also provides a relay adhesion detection device, comprising:

[0029] An adjustment module, used for adjusting a first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0030] An acquisition module, used for acquiring a plurality of voltage data at a second inverter voltage frequency; the voltage data includes a grid voltage and an inverter voltage of an inverter;

[0031] A first determination module, used to determine a comparison value according to a difference between a grid voltage and an inverter voltage in each voltage data;

[0032] The second determination module is used to determine the relay adhesion detection result according to the comparison value and the reference value.

[0033] In a third aspect, the present application further provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0034] Adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0035] Acquire a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter;

[0036] Determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data;

[0037] The relay sticking detection result is determined based on the comparison value and the reference value.

[0038] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the following steps are implemented:

[0039] Adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0040] Acquire a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter;

[0041] Determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data;

[0042] The relay sticking detection result is determined based on the comparison value and the reference value.

[0043] In a fifth aspect, the present application further provides a computer program product, including a computer program, which implements the following steps when executed by a processor:

[0044] Adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0045] Acquire a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter;

[0046] Determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data;

[0047] The relay sticking detection result is determined based on the comparison value and the reference value.

[0048] The above-mentioned relay adhesion detection method, device, equipment, storage medium and program product adjust the first inverter voltage frequency of the inverter to a second inverter voltage frequency equal to the sum of the first inverter voltage frequency and a preset disturbance frequency, and obtain multiple voltage data under the second inverter voltage frequency, determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data, and determine the relay adhesion detection result according to the comparison value and the reference value, thereby realizing the detection of whether a relay in the grid-connected power system has a adhesion fault. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0050] Figure 1 is an internal structure diagram of a computer device provided in an embodiment of the present application;

[0051] Figure 2 It is a structural diagram of a single-phase grid-connected power system provided in an embodiment of the present application;

[0052] Figure 3 It is a flow chart of a relay adhesion detection method provided in an embodiment of the present application;

[0053] Figure 4 is a flow chart of a method for determining a comparison value provided in an embodiment of the present application;

[0054] Figure 5 is a schematic diagram of a target curve corresponding to a target function provided in an embodiment of the present application;

[0055] Figure 6 It is a flowchart of a reference value determination method provided in an embodiment of the present application;

[0056] Figure 7 It is a flow chart of a method for determining an objective function provided in an embodiment of the present application;

[0057] Figure 8 It is a function simulation schematic diagram provided in an embodiment of the present application;

[0058] Fig. 9 It is a flow chart of another relay adhesion detection method provided in an embodiment of the present application;

[0059] Fig.10 It is a structural block diagram of a relay adhesion detection device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0061] The relay adhesion detection method provided in the embodiment of the present application can be applied to Figure 1 The computer device shown may be a terminal, Figure 1It is an internal structure diagram of a computer device provided in an embodiment of the present application. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a relay adhesion detection method is implemented. The display unit of the computer device is used to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device shell, or an external keyboard, touchpad or mouse.

[0062] Those skilled in the art will understand that Figure 1 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0063] The relay adhesion detection method provided in the embodiment of the present application can be applied to a single-phase grid-connected or three-phase grid-connected power system. Figure 2 For explanation. Figure 2 As shown, Figure 2 This is a structural diagram of a single-phase grid-connected power system provided by an embodiment of the present application. The single-phase grid-connected power system includes a first MOS tube S1, a second MOS tube S2, a third MOS tube S3, a fourth MOS tube S4, an inductor L, a capacitor C, a resistor R, a first relay RLY1, a second relay RLY2, and an AC power supply Vin. Among them, Figure 2Vinv in the figure represents the inverter voltage of the inverter, Vgrid represents the grid voltage, and the first MOS tube S1, the second MOS tube S2, the third MOS tube S3, and the fourth MOS tube S4 are switch tubes in the inverter circuit. MOS is the abbreviation of MOSFET. MOSFET Metal-Oxide-Semiconductor Field-Effect Transistor, also known as Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). If a relay has a sticking failure, the inverter cannot be effectively disconnected from the grid, and the subsequent inverter cannot be effectively connected to the grid. Therefore, how to detect whether a relay has a sticking failure in a grid-connected power system has become a technical problem that needs to be solved urgently in this field.

[0064] In order to solve the above technical problems, in an exemplary embodiment, Figure 3 As shown, Figure 3 is a flow chart of a relay adhesion detection method provided in an embodiment of the present application, in which the method is applied to Figure 1 The computer device in is taken as an example to illustrate, including the following steps S301-S304.

[0065] S301, adjusting a first inverter voltage frequency of an inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency.

[0066] The first inverter voltage frequency is the frequency before the inverter voltage frequency of the inverter is disturbed by the preset disturbance frequency, and the second inverter voltage frequency is the frequency after the first inverter voltage frequency of the inverter is disturbed by the preset disturbance frequency, that is, the first inverter voltage frequency is adjusted by the preset disturbance frequency, and the adjusted second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and the preset disturbance frequency. Indicates that the preset disturbance frequency is The second inverter voltage frequency is equal to .

[0067] S302, acquiring a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter.

[0068] After adjusting the first inverter voltage frequency of the inverter to the second inverter voltage frequency, the inverter voltage and the grid voltage of the inverter are detected at the second inverter voltage frequency. The multiple voltage data may be data detected within one inverter voltage cycle of the inverter, or data detected within multiple inverter voltage cycles. Each voltage data includes the grid voltage and the inverter voltage of the inverter, and the grid voltage and the inverter voltage in one voltage data are voltages detected at the same time point.

[0069] S303: Determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data.

[0070] Among them, determining the comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data can be achieved in the following way:

[0071] Method 1: The absolute value of the difference between the grid voltage and the inverter voltage in each voltage data may be determined, and the average value of each absolute value may be determined, and the average value may be used as a comparison value.

[0072] Method 2: The absolute value of the difference between the grid voltage and the inverter voltage in each voltage data may be determined, the square of the average value of each absolute value may be determined, and the square of the average value may be used as a comparison value.

[0073] S304, determining a relay adhesion detection result according to the comparison value and the reference value.

[0074] Among them, the reference value can be determined based on a periodic function, and the periodic function can be a sine function or a cosine function. The inverter voltage of the inverter at the preset rated voltage peak of the inverter and the first inverter voltage frequency can be simulated by cosine function A, and the inverter voltage of the inverter at the preset rated voltage peak of the inverter and the second inverter voltage frequency can be simulated by cosine function B. Assuming that cosine function A corresponds to curve A and cosine function B corresponds to curve B, the absolute value of the difference between the inverter voltage on the moved curve B and the inverter voltage on the curve A can be determined after the curve B is moved on the horizontal axis by a movement amount, and the average value of the absolute value is calculated. As the movement amount of curve B on the horizontal axis changes, a minimum average value will be obtained, and the minimum average value can be used as a reference value. The square of the minimum average value can also be used as a reference value.

[0075] Similarly, the inverter voltage of the inverter at the preset rated voltage peak value and the first inverter voltage frequency of the inverter can be simulated by the sine function C, and the inverter voltage of the inverter at the preset rated voltage peak value and the second inverter voltage frequency of the inverter can be simulated by the sine function D. Assuming that the sine function C corresponds to curve C and the sine function D corresponds to curve D, the absolute value of the difference between the inverter voltage on the moved curve D and the inverter voltage on the curve C can be determined after the curve D is moved on the horizontal axis by a movement amount, and the average value of the absolute value is calculated. As the movement amount of curve D on the horizontal axis changes, a minimum average value will be obtained, and the minimum average value can be used as a reference value. The square of the minimum average value can also be used as a reference value.

[0076] It should be noted that if the minimum average value is used as the reference value, then the comparison value can be determined in S303 using method 1. If the square of the minimum average value is used as the reference value, then the comparison value can be determined in S303 using method 2.

[0077] The method provided in the embodiment of the present application adjusts the first inverter voltage frequency of the inverter to a second inverter voltage frequency that is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency, and obtains multiple voltage data at the second inverter voltage frequency, determines a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data, and determines the relay sticking detection result according to the comparison value and the reference value, thereby realizing the detection of whether a relay sticking fault occurs in the grid-connected power system.

[0078] In an exemplary embodiment, the above S304, determining the relay adhesion detection result according to the comparison value and the reference value, can be implemented as follows:

[0079] If the comparison value is greater than the reference value, the relay non-sticking is taken as the relay sticking detection result;

[0080] If the comparison value is not greater than the reference value, the relay sticking is regarded as the relay sticking detection result.

[0081] Among them, when the comparison value is not greater than the reference value, it means that after the inverter voltage frequency of the inverter is disturbed by the preset disturbance frequency, the inverter voltage on the inverter side is close to the grid voltage, and it can be determined that the relay is stuck.

[0082] The method provided in the embodiment of the present application can determine the relay adhesion detection result by comparing the comparison value with the reference value, thereby improving the efficiency of relay adhesion detection.

[0083] In an exemplary embodiment, Figure 4 As shown, Figure 4 1 is a flow chart of a method for determining a comparison value provided by an embodiment of the present application. This embodiment relates to a possible implementation method of determining a comparison value based on the difference between the grid voltage and the inverter voltage in each voltage data. Based on the above embodiment, the above S303 may include the following steps S401-S402:

[0084] S401, determining the absolute value of the difference between the grid voltage and the inverter voltage in each voltage data.

[0085] S402, determining the average value of each absolute value, and taking the average value as a comparison value.

[0086] The method provided in the embodiment of the present application determines the absolute value of the difference between the grid voltage and the inverter voltage in each voltage data, determines the average value of each absolute value, uses the average value as a comparison value, and then determines the relay adhesion detection result based on the comparison value and the reference value. Since the algorithm for determining the comparison value is simple and the amount of calculation is small, the efficiency of relay adhesion detection is improved.

[0087] In an exemplary embodiment, the reference value is determined using an objective function based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and a preset disturbance frequency;

[0088] Among them, the objective function is:

[0089] ;

[0090] is the preset rated voltage peak value, is the first inverter voltage frequency, is the preset sampling period, is the preset disturbance frequency, , is the number of sampling times of the inverter voltage in one inverter cycle. is greater than or equal to 1 and less than or equal to integer, A time multiple.

[0091] In this embodiment, =311 volts, =50 Hz, = 100 microseconds, = 2 Hz, For example, the objective function The corresponding curve can be found in Figure 5 As shown, Figure 5 is a schematic diagram of a target curve corresponding to a target function provided in an embodiment of the present application. Figure 5 It can be seen that by modifying The location can be obtained The minimum value of The minimum value of The square of the minimum value of is used as the reference value. A time multiple.

[0092] The method provided in the embodiment of the present application determines the reference value by using the objective function based on the first inverter voltage frequency, the preset rated voltage peak value of the inverter, the preset sampling period, and the preset disturbance frequency, and then determines the relay adhesion detection result based on the comparison value and the reference value, thereby realizing the detection of whether the relay in the grid-connected power system has an adhesion fault. Moreover, after determining the reference value, if the relay needs to be tested for adhesion later, the previously determined reference value can be directly used without repeatedly determining the reference value, thereby further improving the efficiency of relay adhesion detection.

[0093] In an exemplary embodiment, Figure 6 As shown, Figure 6 : is a flow chart of a reference value determination method provided by an embodiment of the present application. This embodiment relates to a possible implementation method of how to determine the reference value using an objective function based on the first inverter voltage frequency, the preset rated voltage peak value of the inverter, the preset sampling period, and the preset disturbance frequency. Based on the above embodiment, the method may include the following steps S601-S602:

[0094] S601, determining a target curve corresponding to the target function based on a first inverter voltage frequency, a preset rated voltage peak, a preset sampling period, and a preset disturbance frequency.

[0095] S602: Taking the minimum value on the target curve as a reference value.

[0096] Reference Figure 5 As shown, the minimum value on the target curve can be used as a reference value. Since the target function presents a periodic characteristic, the minimum value within a period of the target function is the minimum value on the target curve, and the minimum value can be used as a reference value.

[0097] The method provided in the embodiment of the present application determines the target curve corresponding to the target function based on the first inverter voltage frequency, the preset rated voltage peak, the preset sampling period, and the preset disturbance frequency, and uses the minimum value on the target curve as a reference value, and then determines the relay sticking detection result based on the comparison value and the reference value, thereby realizing the detection of whether the relay in the grid-connected power system has a sticking fault.

[0098] In an exemplary embodiment, Figure 7 As shown, Figure 7 Schematic diagram of a method for determining an objective function provided in an embodiment of the present application. The method includes the following steps S701-S702.

[0099] S701, obtain a first function and a second function; the first function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak and a first inverter voltage frequency, and the second function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak and a second inverter voltage frequency.

[0100] Among them, the first function is: , the second function is .

[0101] In this embodiment, =311 volts, =50 Hz, = 100 microseconds, =2 Hz, for example Figure 8 As shown, Figure 8 It is a function simulation schematic diagram provided in an embodiment of the present application. Figure 8 The voltage curve of a given inversion cycle is shown in FIG. 8 , where one inversion cycle is 20 milliseconds. The first function corresponds to curve 81 , and the second function corresponds to curve 82 . is the preset sampling period, is the time multiple, Represents an inversion cycle, t is an integer, which is convenient for processor calculation.

[0102] S702: Determine a target function based on the first function and the second function.

[0103] The objective function is used to simulate the movement of curve 82 on the horizontal axis. The average value of the absolute value of the difference between the curve 81 and the curve 81.

[0104] The method provided in the embodiment of the present application obtains the first function and the second function, and determines the target function based on the first function and the second function, thereby laying a foundation for determining the reference value based on the target function, thereby realizing detection of whether a relay in the grid-connected power system has a sticking fault based on the reference value.

[0105] Reference Fig. 9 , Fig. 9 1 is a flow chart of another relay adhesion detection method provided in an embodiment of the present application. The method comprises the following steps S901-S906:

[0106] S901, obtaining a first function and a second function.

[0107] S902: Determine a target function based on the first function and the second function.

[0108] S903, determining a target curve corresponding to the target function based on the first inverter voltage frequency, a preset rated voltage peak, a preset sampling period, and a preset disturbance frequency.

[0109] S904: Use the minimum value on the target curve as a reference value.

[0110] S905, adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency.

[0111] S906, acquiring a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter.

[0112] S907, determining the absolute value of the difference between the grid voltage and the inverter voltage in each voltage data.

[0113] S908, determining the average value of each absolute value, and taking the average value as a comparison value.

[0114] S909, determining a relay adhesion detection result according to the comparison value and the reference value.

[0115] It should be understood that, although the steps in the flowcharts involved in the above embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0116] Based on the same inventive concept, the embodiment of the present application also provides a relay adhesion detection device for implementing the relay adhesion detection method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more relay adhesion detection device embodiments provided below can refer to the limitations of the relay adhesion detection method above, and will not be repeated here.

[0117] In an exemplary embodiment, Fig.10 As shown, Fig.10 1 is a structural block diagram of a relay adhesion detection device provided in an embodiment of the present application, the device 1000 includes:

[0118] An adjustment module 1001 is used to adjust a first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0119] An acquisition module 1002 is used to acquire a plurality of voltage data at a second inverter voltage frequency; the voltage data includes a grid voltage and an inverter voltage of an inverter;

[0120] A first determination module 1003, configured to determine a comparison value according to a difference between a grid voltage and an inverter voltage in each voltage data;

[0121] The second determination module 1004 is used to determine the relay adhesion detection result according to the comparison value and the reference value.

[0122] In one embodiment, the second determination module 1004 is specifically configured to: if the comparison value is greater than the reference value, regard relay non-sticking as the relay sticking detection result; if the comparison value is not greater than the reference value, regard relay sticking as the relay sticking detection result.

[0123] In one embodiment, the first determination module 1003 is specifically used to determine the absolute value of the difference between the grid voltage and the inverter voltage in each voltage data; determine the average value of each absolute value, and use the average value as the comparison value.

[0124] In one of the embodiments, the device 1000 may further include a third determination module, the third determination module being configured to determine the reference value using an objective function based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and a preset disturbance frequency;

[0125] Among them, the objective function is:

[0126] ;

[0127] is the preset rated voltage peak value, is the first inverter voltage frequency, is the preset sampling period, is the preset disturbance frequency, , is the number of sampling times of the inverter voltage in one inverter cycle. is greater than or equal to 1 and less than or equal to integer, A time multiple.

[0128] In one of the embodiments, the third determination module is specifically used to determine the target curve corresponding to the target function based on the first inverter voltage frequency, the preset rated voltage peak, the preset sampling period, and the preset disturbance frequency; and use the minimum value on the target curve as a reference value.

[0129] In one embodiment, the method further comprises:

[0130] Obtaining a first function and a second function; the first function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a first inverter voltage frequency, and the second function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a second inverter voltage frequency;

[0131] Determining a target function based on the first function and the second function;

[0132] Among them, the first function is: , the second function is .

[0133] Each module in the above relay adhesion detection device can be implemented in whole or in part by software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each module.

[0134] In an exemplary embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the following steps are implemented:

[0135] Adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0136] Acquire a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter;

[0137] Determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data;

[0138] The relay sticking detection result is determined based on the comparison value and the reference value.

[0139] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0140] If the comparison value is greater than the reference value, the relay non-sticking is taken as the relay sticking detection result;

[0141] If the comparison value is not greater than the reference value, the relay sticking is regarded as the relay sticking detection result.

[0142] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0143] Determine the absolute value of the difference between the grid voltage and the inverter voltage in each voltage data;

[0144] The average of the absolute values ​​is determined and used as the comparison value.

[0145] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0146] Determining a reference value using an objective function based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and a preset disturbance frequency;

[0147] Among them, the objective function is:

[0148] ;

[0149] is the preset rated voltage peak value, is the first inverter voltage frequency, is the preset sampling period, is the preset disturbance frequency, , is the number of sampling times of the inverter voltage in one inverter cycle. is greater than or equal to 1 and less than or equal to integer, A time multiple.

[0150] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0151] Determining a target curve corresponding to the target function based on the first inverter voltage frequency, a preset rated voltage peak, a preset sampling period, and a preset disturbance frequency;

[0152] Use the minimum value on the target curve as the reference value.

[0153] In one embodiment, when the processor executes the computer program, the processor further implements the following steps:

[0154] Obtaining a first function and a second function; the first function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a first inverter voltage frequency, and the second function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a second inverter voltage frequency;

[0155] Determining a target function based on the first function and the second function;

[0156] Among them, the first function is: , the second function is .

[0157] In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0158] Adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0159] Acquire a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter;

[0160] Determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data;

[0161] The relay sticking detection result is determined based on the comparison value and the reference value.

[0162] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0163] If the comparison value is greater than the reference value, the relay non-sticking is taken as the relay sticking detection result;

[0164] If the comparison value is not greater than the reference value, the relay sticking is regarded as the relay sticking detection result.

[0165] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0166] Determine the absolute value of the difference between the grid voltage and the inverter voltage in each voltage data;

[0167] The average of the absolute values ​​is determined and used as the comparison value.

[0168] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0169] Determining a reference value using an objective function based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and a preset disturbance frequency;

[0170] Among them, the objective function is:

[0171] ;

[0172] is the preset rated voltage peak value, is the first inverter voltage frequency, is the preset sampling period, is the preset disturbance frequency, , is the number of sampling times of the inverter voltage in one inverter cycle. is greater than or equal to 1 and less than or equal to integer, A time multiple.

[0173] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0174] Determining a target curve corresponding to the target function based on the first inverter voltage frequency, a preset rated voltage peak, a preset sampling period, and a preset disturbance frequency;

[0175] Use the minimum value on the target curve as the reference value.

[0176] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0177] Obtaining a first function and a second function; the first function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a first inverter voltage frequency, and the second function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a second inverter voltage frequency;

[0178] Determining a target function based on the first function and the second function;

[0179] Among them, the first function is: , the second function is .

[0180] In one embodiment, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the following steps:

[0181] Adjusting the first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency;

[0182] Acquire a plurality of voltage data at a second inverter voltage frequency; each voltage data includes a grid voltage and an inverter voltage of an inverter;

[0183] Determine a comparison value according to the difference between the grid voltage and the inverter voltage in each voltage data;

[0184] The relay sticking detection result is determined based on the comparison value and the reference value.

[0185] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0186] If the comparison value is greater than the reference value, the relay is not stuck as the relay sticking detection result; if the comparison value is not greater than the reference value, the relay is stuck as the relay sticking detection result.

[0187] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0188] The absolute value of the difference between the grid voltage and the inverter voltage in each voltage data is determined; the average value of each absolute value is determined, and the average value is used as a comparison value.

[0189] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0190] Determining a reference value using an objective function based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and a preset disturbance frequency;

[0191] Among them, the objective function is:

[0192] ;

[0193] is the preset rated voltage peak value, is the first inverter voltage frequency, is the preset sampling period, is the preset disturbance frequency, , is the number of sampling times of the inverter voltage in one inverter cycle. is greater than or equal to 1 and less than or equal to integer, A time multiple.

[0194] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0195] Based on the first inverter voltage frequency, the preset rated voltage peak value, the preset sampling period, and the preset disturbance frequency, a target curve corresponding to the target function is determined; and the minimum value on the target curve is used as a reference value.

[0196] In one embodiment, when the computer program is executed by a processor, the following steps are also implemented:

[0197] Obtaining a first function and a second function; the first function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a first inverter voltage frequency, and the second function is used to simulate the inverter voltage of the inverter under a preset rated voltage peak value and a second inverter voltage frequency;

[0198] Determining a target function based on the first function and the second function;

[0199] Among them, the first function is: , the second function is .

[0200] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0201] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0202] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0203] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for detecting relay adhesion in a grid-connected power system, characterized in that: The method comprises: Adjusting a first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency; Acquire a plurality of voltage data at the second inverter voltage frequency; each of the voltage data includes a grid voltage and an inverter voltage of the inverter; Determining a comparison value according to a difference between a grid voltage and an inverter voltage in each of the voltage data; A relay adhesion detection result is determined according to the comparison value and the reference value.

2. The method according to claim 1, characterized in that The step of determining the relay adhesion detection result according to the comparison value and the reference value comprises: If the comparison value is greater than the reference value, the relay non-sticking is taken as the relay sticking detection result; If the comparison value is not greater than the reference value, relay sticking is taken as the relay sticking detection result.

3. The method according to claim 1 or 2, characterized in that: Determining the comparison value according to the difference between the grid voltage and the inverter voltage in each of the voltage data includes: Determining the absolute value of the difference between the grid voltage and the inverter voltage in each of the voltage data; An average value of the absolute values ​​is determined, and the average value is used as the comparison value.

4. The method according to claim 1 or 2, characterized in that: The method further comprises: Determining the reference value using an objective function based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and the preset disturbance frequency; Wherein, the objective function is: ； is the preset rated voltage peak value, is the first inverter voltage frequency, is the preset sampling period, is the preset disturbance frequency, , is the number of sampling times of the voltage of the inverter in one inversion cycle of the inverter, is greater than or equal to 1 and less than or equal to integer, A time multiple.

5. The method according to claim 4, characterized in that The determining the reference value by using an objective function based on the first inverter voltage frequency, a preset rated voltage peak value of the inverter, a preset sampling period, and the preset disturbance frequency includes: Determining a target curve corresponding to the target function based on the first inverter voltage frequency, the preset rated voltage peak, the preset sampling period, and the preset disturbance frequency; The minimum value on the target curve is used as the reference value.

6. The method according to claim 4, characterized in that The method further comprises: Acquire a first function and a second function; the first function is used to simulate the inverter voltage of the inverter under the preset rated voltage peak value and the first inverter voltage frequency, and the second function is used to simulate the inverter voltage of the inverter under the preset rated voltage peak value and the second inverter voltage frequency; Determining the objective function based on the first function and the second function; Wherein, the first function is: , the second function is .

7. A relay adhesion detection device in a grid-connected power system, characterized in that: The device comprises: An adjustment module, used for adjusting a first inverter voltage frequency of the inverter to obtain a second inverter voltage frequency; the second inverter voltage frequency is equal to the sum of the first inverter voltage frequency and a preset disturbance frequency; An acquisition module, used for acquiring a plurality of voltage data at the second inverter voltage frequency; the voltage data includes a grid voltage and an inverter voltage of the inverter; A first determination module, used for determining a comparison value according to a difference between a grid voltage and an inverter voltage in each of the voltage data; The second determination module is used to determine the relay adhesion detection result according to the comparison value and the reference value.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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