Inverter direct current component zero setting control method and device and medium

Abstract

The invention discloses an inverter direct-current component zero setting control method and device and a medium. The method relates to the field of inverter topology, and solves the problem that the DC compensation control precision of the inverter is reduced due to precision deviation of different sampling ports. Data of output current of an inverter are collected in real time, a first average value is obtained by calculating a current average value in a preset adjustment period, a second average value is obtained by calculating a current average value near a zero crossing point in the preset adjustment period, and then a direct-current component compensation value is adjusted by comparing the two average values. And finally, accurate zero setting of the direct-current component of the output current of the inverter is realized. And the first mean value and the second mean value are simultaneously calculated from the sampling value of the output current, so that the reduction of the control precision caused by the precision deviation of different sampling ports and different transmission paths is avoided. The first mean value and the second mean value are used for performing difference control, so that the influence of chip zero point errors, temperature excursion and the like on the control precision can be effectively eliminated, and the control error caused by inductance value deviation is also solved.

Description

Technical Field

[0001] This application relates to the field of inverter topologies, and particularly to a method, device, and medium for zeroing the DC component of an inverter control output current. Background Art

[0002] As a core device for converting direct current (DC) into alternating current (AC), the waveform quality of the output current of an inverter directly affects the performance and lifespan of load devices. In practical applications, a DC component often exists in the output current of an inverter.

[0003] In a dual buck inverter topology, two independent inductors are used to process the positive and negative half-cycle currents respectively. During the operation of the inverter, the deviation between the two buck inductances in the inverter part will increase the DC component. The output current and the DC bias of the output current are respectively sent to two sampling ports of the chip in real time, and both are used for feedback control. The accuracy deviation of the two sampling ports and the differences in the transmission paths will both lead to a decrease in control accuracy.

[0004] Therefore, how to solve the problem of the decrease in the DC compensation control accuracy of the inverter caused by the accuracy deviation of different sampling ports is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide a method, device, and medium for zeroing the DC component of an inverter control output current, so as to solve the problem of the decrease in the DC compensation control accuracy of the inverter caused by the accuracy deviation of different sampling ports.

[0006] To solve the above technical problem, this application provides a method for zeroing the DC component of an inverter control output current, including:

[0007] Real-time collect the output current value of the inverter;

[0008] Obtain a first mean value based on the average value of the output current values within a preset adjustment period;

[0009] Obtain a second mean value based on the average value of the output current values of the same-time neighborhood sampling points at each zero-crossing point within a preset adjustment period;

[0010] If the first mean value is greater than the second mean value, reduce the DC component compensation value according to a preset DC component adjustment step;

[0011] If the first mean value is less than the second mean value, increase the DC component compensation value according to a preset DC component adjustment step;

[0012] Adjust the inverter control output current according to the adjusted DC component compensation value.

[0013] In a possible implementation, in the above inverter DC component zeroing control method, the real-time acquisition of the output current value of the inverter includes:

[0014] Collect the sampled output current value of the inverter at each preset sampling period;

[0015] Judge whether the cumulative number of power grid cycles reaches a preset number according to the sampled output current value;

[0016] If so, enter the step of obtaining the first mean value according to the average value of the output current values within the preset adjustment period.

[0017] In a possible implementation, in the above inverter DC component zeroing control method, it further includes:

[0018] Generate an output current waveform diagram according to the sampled output current value of the inverter collected;

[0019] Obtain a DC offset waveform diagram according to the second mean value.

[0020] In a possible implementation, in the above inverter DC component zeroing control method, obtaining the first mean value according to the average value of the output current values within the preset adjustment period includes:

[0021] Obtain the first mean value according to the first formula and the average value of the output current values within the preset adjustment period;

[0022] The first formula is: ;

[0023] Wherein, represents the first mean value, represents the zero-crossing moment; n is a positive integer greater than 2, representing the number of zero-crossings, represents the output current value, represents the preset adjustment period is the integral value of all sampled output current values between

[0024] In a possible implementation, in the above inverter DC component zeroing control method, obtaining the second mean value according to the average value of the output current values of the same-time neighborhood sampling points at each zero-crossing within the preset adjustment period includes:

[0025] Obtain the output current values of the front and back symmetric neighborhood sampling points of multiple consecutive zero-crossings;

[0026] Obtain the second mean value according to the second formula and the output current values of each symmetric neighborhood sampling point;

[0027] The second formula is:

[0028] ;

[0029] Among them, represents the second mean value; respectively represent the output current values of the sampling points before the first zero-crossing moment, before the second zero-crossing moment, and before the nth zero-crossing moment; respectively represent the output current values of the sampling points after the first zero-crossing moment, after the second zero-crossing moment, and after the nth zero-crossing moment; n is a positive integer greater than 2, representing the number of zero-crossing points.

[0030] In a possible implementation, in the above inverter DC component zeroing control method, obtaining the output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points includes:

[0031] Obtaining multiple output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points.

[0032] In a possible implementation, in the above inverter DC component zeroing control method, after adjusting the inverter control output current value according to the adjusted DC component compensation value, it further includes:

[0033] Clearing the stored first mean value and the second mean value;

[0034] Returning to the step of collecting the output current value of the inverter every preset sampling period.

[0035] To solve the above technical problems, the present application also provides an inverter DC component zeroing control device, including:

[0036] A collection module, configured to collect the output current value of the inverter in real time;

[0037] A first mean value obtaining module, configured to obtain a first mean value according to the average value of the output current values within a preset adjustment period;

[0038] A second mean value obtaining module, configured to obtain a second mean value according to the average value of the output current values of the same time neighborhood sampling points of each zero-crossing point within a preset adjustment period;

[0039] A first adjustment amount determination module, configured to, if the first mean value is greater than the second mean value, reduce the DC component compensation value according to a preset DC component adjustment step;

[0040] A second adjustment amount determination module, configured to, if the first mean value is less than the second mean value, increase the DC component compensation value according to a preset DC component adjustment step;

[0041] An adjustment module, configured to adjust the inverter control output current according to the adjusted DC component compensation value.

[0042] To solve the above technical problems, the present application also provides an inverter DC component zeroing control device, including:

[0043] A memory for storing a computer program;

[0044] A processor for implementing the steps of the above-mentioned inverter DC component zeroing control method when executing the computer program.

[0045] To solve the above technical problems, the present application also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned inverter DC component zeroing control method are implemented.

[0046] The inverter DC component zeroing control method provided by the present application collects data of the inverter output current in real time, calculates the first mean value by calculating the current average value within a preset adjustment period, calculates the second mean value by calculating the current average value near the zero crossing point within the preset adjustment period, and then adjusts the DC component compensation value by comparing the magnitudes of these two average values, ultimately achieving precise zeroing of the DC component of the inverter output current. The first mean value and the second mean value both come from the calculation of the output current sampling values, avoiding the reduction of control accuracy caused by the precision deviation of different sampling ports and the differences in transmission paths. Using the difference control between the first mean value and the second mean value can effectively eliminate the influence of chip zero error, temperature drift, etc. on the control accuracy, and also solve the control error caused by the deviation of the two inductance values. When the current passes through the zero crossing point, the current is basically 0 and is not affected by the output control current, which can be used as a relatively accurate real-time reference value, and the DC component compensation control is also more precise.

[0047] In addition, the present application also provides a device and a medium, corresponding to the above-mentioned inverter DC component zeroing control method, with the same effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] To more clearly illustrate the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0049] Figure 1 It is a circuit diagram for the DC component zeroing control of a voltage source inverter;

[0050] Figure 2 It is another circuit diagram for the DC component zeroing control of a voltage source inverter;

[0051] Figure 3The figure is a flowchart of a method for zeroing the DC component of an inverter provided by an embodiment of the present application;

[0052] Figure 4 The figure is a waveform diagram of output current sampling provided by an embodiment of the present application;

[0053] Figure 5 The figure is a waveform diagram provided by an embodiment of the present application;

[0054] Figure 6 The figure is a structural diagram of a device for zeroing the DC component of an inverter provided by an embodiment of the present application;

[0055] Figure 7 The figure is a structural diagram of another device for zeroing the DC component of an inverter provided by an embodiment of the present application. Detailed implementation manners

[0056] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of the present application.

[0057] The core of the present application is to provide a method, device and medium for zeroing the DC component of an inverter.

[0058] In order to enable those skilled in the art to better understand the solution of the present application, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0059] The DC component of the inverter output current needs to be strictly controlled. In power systems with high requirements for power quality, data center power supply systems, grid-connected inverters in new energy power generation systems, etc., the magnitude of the DC component of the inverter output current should be less than 0.5% of the rated current.

[0060] Figure 1 The figure is a circuit diagram for zeroing the DC component of a voltage source inverter, as Figure 1 shown. The inverter includes four high-frequency switching tubes (Q1, Q2, Q3, Q4), two filter inductors L1, L2, and diodes (D1, D2, D3, D4). The amplitude and phase of the output voltage are controlled by controlling the on and off of the switching tubes. The output current is sampled as IAC, and IAC is a sine wave waveform. is the DC bias of IAC. The instantaneous sampled value of the inverter output current includes an AC component and a DC bias component to be eliminated. There are the following two traditional schemes for zeroing the DC component:

[0061] Solution 1: During the operation of the inverter, IAC and are sent to two sampling ports of the chip in real time, and both are used for feedback control.

[0062] (1) Calculate an intermediate value once after each sampling: ;

[0063] ;

[0064] (2) Perform an accumulative summation every N grid cycles, calculate the average value of once, and obtain the zero-adjustment mean value: ;

[0065] (3) Zero-adjust the DC component of the output current through for output control feedback.

[0066] Solution 2: Before the inverter is powered on, is sent to the chip, and subsequent control is based on this for feedback control.

[0067] (1) Before the inverter outputs current after power-on, take multiple sampling values of to calculate the average value to obtain the mean value of the DC offset component: ;

[0068] (2) Control the inverter to output current. After the inverter outputs current after power-on, the value is no longer updated;

[0069] (3) Calculate an intermediate difference once after each sampling: ;

[0070] (4) Calculate the average value of once every N grid cycles to obtain the mean value of the difference: ;

[0071] (5) Zero-adjust the DC component of the output current through for output control feedback.

[0072] In Solution 1, IAC and are respectively sent to two sampling ports. The accuracy deviation of these two sampling ports and the differences in the transmission paths may both lead to a decrease in control accuracy. In addition, the differences in the zero-point error and temperature drift of the sampling chip, etc., will also affect the data of the two sampling ports, thereby affecting the control accuracy. In Solution 2, is only sampled before the inverter outputs current and not sampled after the inverter outputs current. Therefore, the decrease in control accuracy caused by the accuracy deviation of the two sampling ports and the differences in the transmission paths is solved. However, due to the existence of the zero-point error and temperature drift of the sampling chip, etc., the control accuracy will still be affected.

[0073] Figure 2 It is a circuit diagram for zeroing the DC component control of another voltage source type inverter, including the traditional H-bridge circuit structure, not just the double buck circuit. As an applicable implementation scenario, it is not limited to this scenario.

[0074] To solve the above problems, this application provides a method for zeroing the DC component control of an inverter. Figure 3 The flowchart of a method for zeroing the DC component control of an inverter provided by an embodiment of this application is as Figure 3 shown and includes:

[0075] S11: Real-time collect the output current value of the inverter;

[0076] S12: Obtain the first mean value according to the average value of the output current values within a preset adjustment period;

[0077] S13: Obtain the second mean value according to the average value of the output current values of the same-time neighborhood sampling points at each zero-crossing point within a preset adjustment period;

[0078] S14: If the first mean value is greater than the second mean value, reduce the DC component compensation value according to a preset DC component adjustment step;

[0079] S15: If the first mean value is less than the second mean value, increase the DC component compensation value according to a preset DC component adjustment step;

[0080] S16: Adjust the inverter control output current according to the adjusted DC component compensation value.

[0081] In step S11, the output current can be sampled by a high-precision current sensor or a Hall element to ensure the accuracy and precision of sampling.

[0082] In step S12, the preset adjustment period refers to a fixed time period set according to actual application requirements for calculating the average value of the output current. The first mean value refers to the average value of all the collected output current values within this preset adjustment period. The collected current values are accumulated through calculation software or a hardware circuit, and then divided by the number of sampling times to obtain the average value. The mean value can also be calculated by integration. By calculating the first mean value, the overall situation of the inverter output current within a cycle is evaluated, providing a benchmark for subsequent comparison and adjustment.

[0083] Each zeroing can be calculated through a sliding time window or start new data acquisition and zeroing calculation after the zeroing of a cycle sampling ends.

[0084] The zero crossing point refers to the center value of the PWM dead zone in the positive and negative half cycles of the inverter output current waveform where the current crosses zero, and the current at this moment is basically 0. The sampling points in the same-time neighborhood refer to the current values collected within a certain time range before and after each zero crossing point. The arithmetic mean of the current sampling values within the symmetric time window centered on the current moment in step S13 can be based on each zero crossing moment (denoted as Ti), taking symmetric positions before and after, such as taking one point at a certain time interval before the zero crossing Ti and the same time interval after, or multiple points within the symmetric time window around the zero crossing. It can also sample at the time points after each Ti, such as points within a certain period of time after Ti, or only take some points after Ti, such as Ti+Δt, Ti+2Δt, etc. It can also sample at the time points before each Ti, such as Ti-Δt, Ti-2Δt, etc. Just keep the same-time neighborhood sampling points for each zero crossing point.

[0085] In step S14 and step S15, different zero-adjustment directions are adopted based on the magnitude relationship between the first mean value and the second mean value. By comparing the first mean value and the second mean value, it can be judged whether there is a DC component in the inverter output current.

[0086] If the first mean value is greater than the second mean value , it indicates that there is a positive DC component in the inverter output current. At this time, according to the preset DC component adjustment step size (which can be a fixed value or a value dynamically adjusted according to specific conditions), the DC component compensation value is adjusted to decrease. The purpose is to offset the DC component in the output current by reducing the compensation value.

[0087] If the first mean value is less than the second mean value , it indicates that there is a negative DC component in the inverter output current. At this time, similarly according to the preset DC component adjustment step size, the DC component compensation value is adjusted to increase. The purpose is to offset the DC component in the output current by increasing the compensation value.

[0088] , then ;

[0089] , then ;

[0090] Among them, is the DC component adjustment step size, is the DC component compensation value, and the initial value of

[0091] In step S16, the control output current of the inverter is adjusted according to the adjusted DC component compensation value. This step is implemented through the control system inside the inverter. By changing the control signal, the output current of the inverter is adjusted so that its DC component approaches zero.

[0092] The control output current of the inverter after DC component compensation is: , where I represents the magnitude of the original current, represents the phase angle.

[0093] Through the inverter DC component zeroing control method provided by the embodiments of the present application, by collecting the data of the output current of the inverter in real time, and using the calculated average value of the current within the preset adjustment period to obtain the first average value, and calculating the average value of the current near the zero crossing within the preset adjustment period to obtain the second average value, and then comparing the magnitudes of these two average values to adjust the DC component compensation value, finally realizing the precise zeroing of the DC component of the inverter output current. The first average value and the second average value both come from the calculation of the output current sampling values, avoiding the reduction of control accuracy caused by the accuracy deviation of different sampling ports and the difference in the transmission path. Using the difference control of the first average value and the second average value can effectively eliminate the influence of chip zero error, temperature drift, etc. on the control accuracy, and also solve the control error caused by the deviation of the two buck inductance values. When the current passes through the zero crossing, the current is basically 0 and is not affected by the output control current, so it can be used as a relatively accurate real-time reference value, and the DC component compensation control is also more accurate.

[0094] According to the above embodiments, in order to significantly improve the dynamic response speed and anti-interference ability of the system while ensuring the control accuracy, in a more specific embodiment of the above inverter DC component zeroing control method, the real-time acquisition of the output current value of the inverter includes:

[0095] Collect the sampled output current value of the inverter at each preset sampling period;

[0096] Judge whether the cumulative number of power grid cycles reaches the preset number according to the sampled output current value;

[0097] If so, enter the step of obtaining the first average value according to the average value of the output current values within the preset adjustment period.

[0098] It should be noted that the preset sampling period refers to the time interval of current sampling, which should be much smaller than the power grid cycle (for example, the fundamental cycle of a 50Hz power grid is 20ms); a high-precision current sensor is used to collect the output current signal. Configure the timer interrupt to trigger the sampling task at each preset sampling period.

[0099] For each detected power grid cycle (based on zero-crossing detection), the counter is incremented by 1. Zero-crossing detection can be implemented by a hardware comparator. If the counter value ≥ the preset quantity N, it enters the step of obtaining the first mean value according to the average value of the output current values within the preset adjustment period; otherwise, continue sampling and counting. The preset quantity N is usually set to 5 - 10 power grid cycles, and the specific value depends on the trade-off between the control accuracy requirement and the system dynamic response speed. Whether the number of power grid cycles accumulates to reach the preset quantity is the above-mentioned preset adjustment period.

[0100] By accumulating the sampling data of multiple power grid cycles, the reliability of the data is improved, and the noise and errors that may be introduced by single-cycle sampling are avoided.

[0101] According to the above embodiment, in a more specific embodiment of the above inverter DC component zeroing control method, it further includes:

[0102] Generate an output current waveform diagram based on the sampled output current values of the inverter collected;

[0103] Obtain a DC offset waveform diagram according to the second mean value.

[0104] Figure 4 This is an output current sampling waveform diagram provided by the embodiment of the present application, that is, the IAC sampling waveform diagram. In this embodiment, by generating an output current waveform diagram, the real-time state of the inverter output current is intuitively displayed, which is convenient for subsequent analysis of the zero-crossing current value and the DC component.

[0105] Figure 5 This is one provided by the embodiment of the present application Waveform diagram. The second mean value refers to the average value of the output current values of the sampling points in the same time neighborhood of each zero-crossing within the preset adjustment period. Plot the change of the second mean value over time as a waveform diagram to intuitively display the change trend of the DC component.

[0106] According to the above embodiment, in a more specific embodiment of the above inverter DC component zeroing control method, obtaining the first mean value according to the average value of the output current values within the preset adjustment period includes:

[0107] Obtain the first mean value according to the first formula and the average value of the output current values within the preset adjustment period;

[0108] The first formula is: ;

[0109] Wherein, represents the first mean value, represents the zero-crossing moment; n is a positive integer greater than 2, representing the number of zero-crossings, represents the output current value, represents the preset adjustment period The integral value of the output current values sampled between them.

[0110] Calculate the average value of IAC within the time window range by the first formula. For example, if n = 3, then calculate the sum of the cumulative values of all samples in (t1~t2) and the cumulative values of all samples in (t2~t3), and then calculate the mean value according to the preset adjustment period The output current value of the IAC preset adjustment period represents the current values collected within the preset adjustment period. The average value of the output current values within the preset adjustment period is calculated by the first formula.

[0111] In addition, obtaining the second mean value according to the average value of the output current values of the same-time neighborhood sampling points at each zero-crossing point within the preset adjustment period includes:

[0112] Obtain the output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points;

[0113] Obtain the second mean value according to the second formula and the output current values of each symmetric neighborhood sampling point;

[0114] The second formula is:

[0115] ;

[0116] Where represents the second mean value; respectively represent the output current values of the sampling points before the first zero-crossing moment, before the second zero-crossing moment, and before the nth zero-crossing moment; respectively represent the output current values of the sampling points after the first zero-crossing moment, after the second zero-crossing moment, and after the nth zero-crossing moment; n is a positive integer greater than 2, representing the number of zero-crossing points.

[0117] The front and rear symmetric neighborhood sampling points refer to the current values collected at symmetric positions before and after the zero-crossing moment, ensuring data symmetry. The average value of the output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points is calculated by the second formula.

[0118] Specifically, obtaining the output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points includes:

[0119] Obtain multiple output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points.

[0120] That is, take multiple output current values before and after each zero-crossing point. For example, take 3 output current values before each zero-crossing point and 3 output current values after each zero-crossing point to improve the accuracy of calculation and judgment.

[0121] In a more specific embodiment of the inverter DC component zeroing control method according to the above embodiment, after adjusting the inverter control output current value according to the adjusted DC component compensation value, the method further includes:

[0122] Clear the stored first mean value and second mean value;

[0123] Return to the step of collecting the output current value of the inverter every preset sampling period.

[0124] The clearing process refers to resetting the stored first mean value and second mean value to zero to ensure that the calculation in the next adjustment cycle is not affected by the data of the previous cycle.

[0125] After adjusting the DC component compensation value each time, set the variables of the stored first mean value and second mean value to zero. After the clearing process, restart the data collection process and collect the output current value according to the preset sampling period.

[0126] In the above embodiment, the inverter DC component zeroing control method is described in detail. The present application also provides an embodiment corresponding to the inverter DC component zeroing control device. It should be noted that the present application describes the embodiment of the device part from two perspectives, one is from the perspective of functional modules, and the other is from the perspective of hardware.

[0127] From the perspective of functional modules, Figure 6 is a structural diagram of an inverter DC component zeroing control device provided by an embodiment of the present application. As Figure 6 shown, an inverter DC component zeroing control device includes:

[0128] A collection module 11 for collecting the output current value of the inverter in real time;

[0129] A first mean value obtaining module 12 for obtaining a first mean value according to the average value of the output current values within a preset adjustment period;

[0130] A second mean value obtaining module 13 for obtaining a second mean value according to the average value of the output current values of the same-time neighborhood sampling points at each zero-crossing point within a preset adjustment period;

[0131] A first adjustment amount determining module 14 for reducing the DC component compensation value by a preset DC component adjustment step if the first mean value is greater than the second mean value;

[0132] A second adjustment amount determining module 15 for increasing the DC component compensation value by a preset DC component adjustment step if the first mean value is less than the second mean value;

[0133] An adjustment module 16, configured to adjust the inverter control output current according to the adjusted DC component compensation value.

[0134] Since the embodiments in the device part correspond to those in the method part, for the embodiments in the device part, please refer to the descriptions of the embodiments in the method part, which will not be elaborated here.

[0135] Figure 7 As shown in the structure diagram of another inverter DC component zeroing control device provided by the embodiments of the present application, Figure 7 the inverter DC component zeroing control device includes: a memory 20, configured to store a computer program;

[0136] a processor 21, configured to implement the steps of the method for obtaining user operation habit information as described in the above embodiments (inverter DC component zeroing control method) when executing the computer program.

[0137] The inverter DC component zeroing control device provided in this embodiment may include, but is not limited to, a mobile terminal, a personal computer, a workstation, etc.

[0138] Among them, the processor 21 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 21 may be implemented in at least one hardware form of a digital signal processor (DSP), a field-programmable gate array (FPGA), or a programmable logic array (PLA). The processor 21 may also include a main processor and a coprocessor. The main processor is a processor used to process data in the wake state, also known as a central processing unit (CPU); the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, the processor 21 may be integrated with a graphics processing unit (GPU), and the GPU is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 21 may further include an artificial intelligence (AI) processor, and the AI processor is used to process computing operations related to machine learning.

[0139] The memory 20 may include one or more computer-readable storage media, which may be non-transitory. The memory 20 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices and flash storage devices. In this embodiment, the memory 20 is at least used to store the following computer program 201. After the computer program is loaded and executed by the processor 21, the relevant steps of the inverter DC component zeroing control method disclosed in any of the foregoing embodiments can be implemented. In addition, the resources stored in the memory 20 may also include an operating system 202, data 203, etc., and the storage method may be transient storage or permanent storage. Among them, the operating system 202 may include Windows, Unix, Linux, etc. The data 203 may include, but is not limited to, the data involved in implementing the inverter DC component zeroing control method.

[0140] In some embodiments, the inverter DC component zeroing control device may further include a display screen 22, an input / output interface 23, a communication interface 24, a power supply 25, and a communication bus 26.

[0141] Those skilled in the art can understand that Figure 7 the structure shown in does not constitute a limitation on the inverter DC component zeroing control device, and may include more or fewer components than shown in the figure.

[0142] The inverter DC component zeroing control device provided by the embodiment of the present application includes a memory and a processor. When the processor executes the program stored in the memory, the following method can be implemented: the inverter DC component zeroing control method.

[0143] Finally, the present application also provides an embodiment corresponding to a computer-readable storage medium. A computer program is stored on the computer-readable storage medium, and when the computer program is executed by the processor, the steps recorded in the inverter DC component zeroing control method embodiment as described above are implemented.

[0144] It can be understood that if the method in the above embodiments is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and executes all or part of the steps of the methods described in the various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0145] The computer-readable storage medium provided in this embodiment stores a computer program, and when the processor executes the program, the following method can be implemented: an inverter DC component zeroing control method.

[0146] The inverter DC component zeroing control method, device and medium provided in the present application have been introduced in detail above. The various embodiments in the specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method part. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

[0147] It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including the said element.

Claims

1. A method for zeroing the DC component of an inverter, characterized in that, Including: Real-time collect the output current value of the inverter; Obtain the first mean value according to the average value of the output current values within a preset adjustment period; Obtain the second mean value according to the average value of the output current values of the same-time neighborhood sampling points at each zero-crossing point within a preset adjustment period; If the first mean value is greater than the second mean value, reduce and adjust the DC component compensation value according to a preset DC component adjustment step; If the first mean value is less than the second mean value, increase and adjust the DC component compensation value according to a preset DC component adjustment step; Adjust the inverter control output current according to the adjusted DC component compensation value.

2. The inverter DC component zeroing control method according to claim 1, characterized in that The real-time collection of the output current value of the inverter includes: Collect the sampled output current value of the inverter at every preset sampling period; Judge whether the cumulative number of power grid cycles reaches a preset number according to the sampled output current value; If so, enter the step of obtaining the first mean value according to the average value of the output current values within a preset adjustment period.

3. The inverter DC component zeroing control method according to claim 2, wherein It also includes: Generate an output current waveform diagram according to the sampled output current value of the collected inverter; Obtain a DC offset amount waveform diagram according to the second mean value.

4. The zero-crossing control method for the DC component of the inverter according to claim 3, characterized in that, Obtaining the first mean value according to the average value of the output current values within a preset adjustment period includes: Obtain the first mean value according to the first formula and the average value of the output current values within a preset adjustment period; The first formula is as follows: ; Among them, represents the first mean value, represents the zero-crossing moment; n is a positive integer greater than 2, representing the number of zero-crossings, represents the output current value, represents the preset adjustment period is the integral value of all sampled output current values between them.

5. The inverter DC component zeroing control method according to claim 4, wherein The obtaining the second mean value according to the average value of the output current values of the same-time neighborhood sampling points at each zero-crossing point within a preset adjustment period includes: Obtain the output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points; Obtain the second mean value according to the second formula and the output current values of each symmetric neighborhood sampling point; The second formula is: ； Among them, represents the second mean value; respectively represent the sampled point output current values before the first zero-crossing moment, before the second zero-crossing moment, and before the nth zero-crossing moment; respectively represent the sampled point output current values after the first zero-crossing moment, after the second zero-crossing moment, and after the nth zero-crossing moment; n is a positive integer greater than 2, representing the number of zero-crossing points.

6. The inverter DC component zeroing control method according to claim 5, characterized in that, Obtaining the output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points includes: Obtain multiple output current values of the front and rear symmetric neighborhood sampling points of multiple consecutive zero-crossing points.

7. The inverter DC component zeroing control method according to claim 2, characterized in that After adjusting the inverter control output current value according to the adjusted DC component compensation value, it further includes: Clear the stored first mean value and the second mean value; Return to the step of collecting the output current value of the inverter at every preset sampling period.

8. A zero-crossing control device for the DC component of an inverter, characterized in that, Including: A collection module for real-time collecting the output current value of the inverter; A first mean value obtaining module for obtaining the first mean value according to the average value of the output current values within a preset adjustment period; A second mean value obtaining module for obtaining the second mean value according to the average value of the output current values of the same-time neighborhood sampling points at each zero-crossing point within a preset adjustment period; A first adjustment amount determining module for, if the first mean value is greater than the second mean value, reducing and adjusting the DC component compensation value according to a preset DC component adjustment step; A second adjustment amount determining module for, if the first mean value is less than the second mean value, increasing and adjusting the DC component compensation value according to a preset DC component adjustment step; An adjustment module for adjusting the inverter control output current according to the adjusted DC component compensation value.

9. A zero-crossing control device for the DC component of an inverter, characterized in that, Including: A memory for storing a computer program; A processor for implementing the steps of the inverter DC component zeroing control method according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, characterized in that, A computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the steps of the inverter DC component zeroing control method described in any one of claims 1 to 7 are implemented.

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