Inverter control method and device, electronic equipment and readable storage medium

Abstract

The invention relates to the technical field of electronic power, and provides an inverter control method and device, electronic equipment and a readable storage medium, and the inverter control method comprises the steps: obtaining a first voltage of a power grid; determining a first angular frequency and a first phase corresponding to the power grid according to the first voltage; acquiring a second angular frequency and a second phase of the inverter; determining a first frequency difference according to the first angular frequency and the second angular frequency; determining a first phase difference according to the first phase and the second phase; determining a target voltage of the inverter according to the first frequency difference and the first phase difference; and controlling the duty ratio of a switching element of the inverter according to the target voltage. According to the control method of the inverter provided by the invention, when the inverter is connected to the power grid, the synchronization between the inverter and the operation parameters of the power grid can be ensured, large impact on the inverter can be avoided, and the stable operation of the inverter is ensured.

Description

Technical Field

[0001] The present application relates to the field of electronic power technology, and in particular to a control method, a control device, an electronic device and a readable storage medium for an inverter. Background Art

[0002] In the related art, when the inverter is operating off-grid, it is usually necessary to switch from the off-grid state to the grid power supply state after the grid returns to normal. In order to reduce the impact during the switching process, it is generally necessary to synchronize the operating parameters on the inverter side with the operating parameters on the grid side before switching, so that the voltage, frequency, phase and other parameters on the inverter side are basically consistent with those on the grid side. However, since the inverter frequency tracking and phase adjustment will affect each other, when the frequency tracking is in place, there may be an error in the phase. When the phase error is very small, due to the existence of the frequency error, the phase error will expand again as time accumulates. Therefore, how to improve the synchronization accuracy of the inverter's operating parameters and the grid's operating parameters has become a technical problem that needs to be solved urgently. Summary of the invention

[0003] The present application aims to at least solve the technical problem in the prior art that an inverter is subjected to a significant impact due to asynchrony of operating parameters during connection to a power grid.

[0004] To this end, a first aspect of the present application is to propose a control method for an inverter.

[0005] A second aspect of the present application is to provide a control device for an inverter.

[0006] A third aspect of the present application is to provide an electronic device.

[0007] A fourth aspect of the present application is to provide a readable storage medium.

[0008] In view of this, according to the first aspect of the present application, a control method for an inverter is proposed, wherein the inverter includes multiple switching elements, and the control method for the inverter includes: obtaining a first voltage of a power grid; determining a first angular frequency and a first phase corresponding to the power grid based on the first voltage; obtaining a second angular frequency and a second phase of the inverter; determining a first frequency difference based on the first angular frequency and the second angular frequency; determining a first phase difference based on the first phase and the second phase; determining a target voltage of the inverter based on the first frequency difference and the first phase difference; and controlling the duty cycle of the switching elements of the inverter based on the target voltage.

[0009] The control method of the inverter provided in the present application can be used to synchronize the operating parameters of the inverter, such as voltage, frequency and phase, with the operating parameters of the power grid before the inverter is connected to the power grid, so as to ensure that the operating parameters of the inverter are close to the operating parameters of the power grid, thereby avoiding a large impact on the inverter during the process of connecting to the power grid and ensuring the stable operation of the inverter.

[0010] Before the inverter is connected to the power grid, first, the first voltage of the power grid is obtained, and according to the first voltage of the power grid, the first angular frequency and the first phase corresponding to the power grid are determined. Then the second angular frequency and the second phase of the inverter are obtained. It is understandable that before the inverter is connected to the power grid, in order to ensure the synchronization of the operating parameters of the inverter and the operating parameters of the power grid, it is necessary to first determine the operating parameters of the inverter and the operating parameters of the power grid, compare the operating parameters of the two, and determine the difference between the operating parameters of the two, and then synchronize the operating parameters according to the difference between the operating parameters of the two. That is, the first angular frequency and the first phase of the power grid are determined respectively, and the second angular frequency and the second phase of the inverter are determined.

[0011] Further, the first frequency difference is determined according to the first angular frequency and the second angular frequency, and the first phase difference is determined according to the first term and the second phase. That is, after obtaining the first angular frequency and the first phase of the power grid, and the second angular frequency and the second phase of the inverter, the difference between the two can be calculated respectively. That is, the first frequency difference and the first phase difference are used to determine the difference between the operating parameters of the power grid and the inverter, so as to synchronize the operating parameters.

[0012] Furthermore, the target voltage of the inverter is determined according to the first frequency difference and the first phase difference, and then the duty cycle of the switch of the inverter is controlled according to the target voltage of the inverter, so that the synchronization of the operating parameters of the inverter and the power grid can be completed. It can be understood that the operation process of the inverter is realized by controlling the on-off of multiple switch components included in the inverter, that is, during the operation of the inverter, the on-off of multiple switch components can be controlled according to the required duty cycle, and the duty cycle of the switch components directly affects the operating parameters of the voltage, frequency and phase of the inverter.

[0013] Therefore, in the process of controlling the inverter, the target voltage required by the inverter is determined according to the first frequency difference and the first phase difference, so that the target voltage required by the inverter can be determined according to the difference between the operating parameters of the inverter and the power grid, and then the duty cycle of the switch of the inverter is determined according to the target voltage, and finally the inverter operation can be controlled according to the determined duty cycle. In this way, in the process of the inverter operating at the required target voltage, the synchronization between the operating parameters of the inverter and the operating parameters of the power grid can be ensured, so that in the process of the inverter being connected to the power grid, a large impact on the inverter can be avoided, and the stable operation of the inverter can be ensured.

[0014] The control method of the inverter provided in the present application, before the inverter is connected to the power grid, first obtains the first voltage of the power grid, and then determines the first angular frequency and the first phase of the power grid according to the first voltage, and then obtains the second angular frequency and the second phase of the inverter, and then can determine the first frequency difference according to the first angular frequency and the second angular frequency, and determine the first phase difference according to the first phase and the second phase, that is, determine the difference between the operating parameters of the inverter and the power grid. Then, the target voltage of the inverter is determined according to the first frequency difference and the first phase difference, and finally the duty cycle of the switching element of the inverter is controlled according to the target voltage, so as to ensure the synchronization between the operating parameters of the inverter and the power grid, avoid a large impact on the inverter, and ensure the stable operation of the inverter.

[0015] In some technical schemes, optionally, the target voltage of the inverter is determined based on the first frequency difference and the first phase difference, including: obtaining the natural frequency and voltage amplitude of the inverter; determining the output angular frequency of the inverter based on the first frequency difference, the first phase difference and the natural frequency; determining the target voltage based on the output angular frequency and the voltage amplitude.

[0016] In some technical schemes, optionally, the output angular frequency of the inverter is determined based on the first frequency difference, the first phase difference and the natural frequency, including: superimposing the first frequency difference and the first phase difference to generate a superimposed value; inputting the superimposed value to a linear controller to generate an angular frequency adjustment amount of the inverter; and superimposing the angular frequency adjustment amount and the natural frequency to generate the output angular frequency.

[0017] In some technical solutions, optionally, the target voltage is determined based on the output angular frequency and the voltage amplitude, including: inputting the output angular frequency into an integrator to generate a real-time phase of the inverter; performing a sinusoidal calculation on the real-time phase; and superimposing the real-time phase after the sinusoidal calculation with the voltage amplitude to generate the target voltage.

[0018] In some technical solutions, optionally, before determining the output angular frequency of the inverter based on the first frequency difference, the first phase difference and the natural frequency, the control method also includes: inputting the first frequency difference into an amplifier to amplify the first frequency difference; and adjusting the first phase difference according to a preset adjustment algorithm.

[0019] In some technical solutions, optionally, determining a first angular frequency and a first phase corresponding to the power grid according to the first voltage includes: inputting the first voltage into a digital phase-locked loop to generate the first angular frequency and the first phase.

[0020] In some technical solutions, optionally, the duty cycle of the switching element of the inverter is controlled according to the target voltage, including: obtaining the DC bus voltage of the inverter; calculating the DC bus voltage and the target voltage according to a pulse width modulation algorithm to determine the duty cycle of the switching element; and controlling the switching element to be turned on and off according to the duty cycle.

[0021] According to a second aspect of the present application, a control device for an inverter is proposed, wherein the inverter includes a plurality of switch elements, and the control device for the inverter includes: an acquisition unit for acquiring a first voltage of a power grid; a determination unit for determining a first angular frequency and a first phase corresponding to the power grid based on the first voltage; the acquisition unit is also used to acquire a second angular frequency and a second phase of the inverter; the determination unit is also used to determine a first frequency difference based on the first angular frequency and the second angular frequency; and to determine a first phase difference based on the first phase and the second phase; and to determine a target voltage of the inverter based on the first frequency difference and the first phase difference; a control unit is used to control the duty cycle of the switch elements of the inverter based on the target voltage.

[0022] The control device of the inverter provided in the present application first obtains the first voltage of the power grid before the inverter is connected to the power grid, and then determines the first angular frequency and the first phase of the power grid according to the first voltage, and then obtains the second angular frequency and the second phase of the inverter, and then can determine the first frequency difference according to the first angular frequency and the second angular frequency, and determine the first phase difference according to the first phase and the second phase, that is, determine the difference between the operating parameters of the inverter and the power grid. Then, the target voltage of the inverter is determined according to the first frequency difference and the first phase difference, and finally the duty cycle of the switching element of the inverter is controlled according to the target voltage, so as to ensure the synchronization between the operating parameters of the inverter and the power grid, avoid a large impact on the inverter, and ensure the stable operation of the inverter.

[0023] In some technical solutions, optionally, the acquisition unit is also used to obtain the natural frequency and voltage amplitude of the inverter; the determination unit is specifically used to determine the output angular frequency of the inverter based on the first frequency difference, the first phase difference and the natural frequency; and determine the target voltage based on the output angular frequency and the voltage amplitude.

[0024] In some technical solutions, optionally, the determination unit is also specifically used to: superimpose the first frequency difference and the first phase difference to generate a superimposed value; input the superimposed value to a linear controller to generate an angular frequency adjustment amount of the inverter; superimpose the angular frequency adjustment amount and the natural frequency to generate an output angular frequency.

[0025] In some technical solutions, optionally, the determination unit is also specifically used to: input the output angular frequency to an integrator to generate a real-time phase of the inverter; perform a sinusoidal calculation on the real-time phase; and superimpose the real-time phase after the sinusoidal calculation with the voltage amplitude to generate a target voltage.

[0026] In some technical solutions, optionally, the control device of the inverter also includes: an amplification unit, used to input the first frequency difference into an amplifier to amplify the first frequency difference; and a setting unit, used to set the first phase difference according to a preset setting algorithm.

[0027] In some technical solutions, optionally, the determination unit is further configured to: input the first voltage into a digital phase-locked loop to generate a first angular frequency and a first phase.

[0028] In some technical solutions, optionally, the acquisition unit is also used to obtain the DC bus voltage of the inverter; the determination unit is also used to calculate the DC bus voltage and the target voltage according to the pulse width modulation algorithm to determine the duty cycle of the switch element; the control unit is specifically used to control the on and off of the switch element according to the duty cycle.

[0029] According to the third aspect of the present application, an electronic device is proposed, comprising: a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the inverter control method in any one of the above technical solutions are implemented. Therefore, the electronic device has all the beneficial effects of the inverter control method in any one of the above technical solutions, which will not be repeated here.

[0030] According to the fourth aspect of the present application, a readable storage medium is provided, on which a program or instruction is stored, and when the program or instruction is executed by a processor, a control method for an inverter as in any of the above technical solutions is implemented. Therefore, the readable storage medium has all the beneficial effects of the control method for an inverter in any of the above technical solutions, which will not be described in detail here.

[0031] Additional aspects and advantages of the present application will become apparent in the following description or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0033] Figure 1 A schematic diagram showing a flow chart of a method for controlling an inverter according to an embodiment of the present application is shown;

[0034] Figure 2 A circuit diagram showing an inverter control method according to an embodiment of the present application is applied;

[0035] Figure 3 The figure shows the voltage curve during the control process of the inverter according to the embodiment of the present application;

[0036] Figure 4 shows a frequency curve during the control process of the inverter according to an embodiment of the present application;

[0037] Figure 5 The phase curve in the control process of the inverter according to the embodiment of the present application is shown;

[0038] Figure 6 A structural block diagram of a control device for an inverter according to an embodiment of the present application is shown;

[0039] Figure 7 A structural block diagram of an electronic device according to an embodiment of the present application is shown.

[0040] Reference numerals:

[0041] 600 is a control device for an inverter, 602 is an acquisition unit, 604 is a determination unit, 606 is a control unit, 700 is an electronic device, 702 is a processor, and 704 is a memory. DETAILED DESCRIPTION

[0042] In order to more clearly understand the above-mentioned purposes, features and advantages of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0043] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0044] Combine the following Figures 1 to 7 , the control method, control device, electronic device and readable storage medium of the inverter provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.

[0045] like Figure 1 As shown, an embodiment of the present application provides a control method for an inverter, wherein the inverter includes a plurality of switch elements, and the control method for the inverter includes:

[0046] Step 102, obtaining a first voltage of a power grid;

[0047] Step 104, determining a first angular frequency and a first phase corresponding to the power grid according to the first voltage;

[0048] Step 106, obtaining a second angular frequency and a second phase of the inverter;

[0049] Step 108, determining a first frequency difference according to the first angular frequency and the second angular frequency;

[0050] Step 110, determining a first phase difference according to the first phase and the second phase;

[0051] Step 112, determining a target voltage of the inverter according to the first frequency difference and the first phase difference;

[0052] Step 114, controlling the duty cycle of the switching element of the inverter according to the target voltage.

[0053] The control method of the inverter provided in the present application can be used to synchronize the operating parameters of the inverter, such as voltage, frequency and phase, with the operating parameters of the power grid before the inverter is connected to the power grid, so as to ensure that the operating parameters of the inverter are close to the operating parameters of the power grid, thereby avoiding a large impact on the inverter during the process of connecting to the power grid and ensuring the stable operation of the inverter.

[0054] Before the inverter is connected to the power grid, first, the first voltage of the power grid is obtained, and according to the first voltage of the power grid, the first angular frequency and the first phase corresponding to the power grid are determined. Then the second angular frequency and the second phase of the inverter are obtained. It is understandable that before the inverter is connected to the power grid, in order to ensure the synchronization of the operating parameters of the inverter and the operating parameters of the power grid, it is necessary to first determine the operating parameters of the inverter and the operating parameters of the power grid, compare the operating parameters of the two, and determine the difference between the operating parameters of the two, and then synchronize the operating parameters according to the difference between the operating parameters of the two. That is, the first angular frequency and the first phase of the power grid are determined respectively, and the second angular frequency and the second phase of the inverter are determined.

[0055] Further, the first frequency difference is determined according to the first angular frequency and the second angular frequency, and the first phase difference is determined according to the first term and the second phase. That is, after obtaining the first angular frequency and the first phase of the power grid, and the second angular frequency and the second phase of the inverter, the difference between the two can be calculated respectively. That is, the first frequency difference and the first phase difference are used to determine the difference between the operating parameters of the power grid and the inverter, so as to synchronize the operating parameters.

[0056] Furthermore, the target voltage of the inverter is determined according to the first frequency difference and the first phase difference, and then the duty cycle of the switch of the inverter is controlled according to the target voltage of the inverter, so that the synchronization of the operating parameters of the inverter and the power grid can be completed. It can be understood that the operation process of the inverter is realized by controlling the on-off of multiple switch components included in the inverter, that is, during the operation of the inverter, the on-off of multiple switch components can be controlled according to the required duty cycle, and the duty cycle of the switch components directly affects the operating parameters of the voltage, frequency and phase of the inverter.

[0057] Therefore, in the process of controlling the inverter, the target voltage required by the inverter is determined according to the first frequency difference and the first phase difference, so that the target voltage required by the inverter can be determined according to the difference between the operating parameters of the inverter and the power grid, and then the duty cycle of the switch of the inverter is determined according to the target voltage, and finally the inverter operation can be controlled according to the determined duty cycle. In this way, in the process of the inverter operating at the required target voltage, the synchronization between the operating parameters of the inverter and the operating parameters of the power grid can be ensured, so that in the process of the inverter being connected to the power grid, a large impact on the inverter can be avoided, and the stable operation of the inverter can be ensured.

[0058] The control method of the inverter provided in the present application, before the inverter is connected to the power grid, first obtains the first voltage of the power grid, and then determines the first angular frequency and the first phase of the power grid according to the first voltage, and then obtains the second angular frequency and the second phase of the inverter, and then can determine the first frequency difference according to the first angular frequency and the second angular frequency, and determine the first phase difference according to the first phase and the second phase, that is, determine the difference between the operating parameters of the inverter and the power grid. Then, the target voltage of the inverter is determined according to the first frequency difference and the first phase difference, and finally the duty cycle of the switching element of the inverter is controlled according to the target voltage, so as to ensure the synchronization between the operating parameters of the inverter and the power grid, avoid a large impact on the inverter, and ensure the stable operation of the inverter.

[0059] In some embodiments, optionally, determining the target voltage of the inverter based on the first frequency difference and the first phase difference includes: obtaining the natural frequency and voltage amplitude of the inverter; determining the output angular frequency of the inverter based on the first frequency difference, the first phase difference and the natural frequency; and determining the target voltage based on the output angular frequency and the voltage amplitude.

[0060] In this embodiment, in the process of determining the target voltage of the inverter, first, the natural frequency and voltage amplitude of the inverter can be obtained. It can be understood that the natural frequency and voltage amplitude of the inverter are determined based on the hardware parameters of the inverter itself, that is, the natural frequency and voltage amplitude are characteristics of the inverter itself, and can be directly obtained based on the hardware parameters of the inverter.

[0061] Further, after determining the first frequency difference between the first angular frequency and the second angular frequency, and determining the first phase difference between the first phase and the second phase, the output angular frequency of the inverter can be determined according to the first frequency difference, the first phase difference and the natural frequency of the inverter. That is, the output angular frequency required by the inverter after being connected to the power grid. Further, the target voltage of the inverter can be determined according to the output angular frequency required by the inverter and the voltage amplitude of the inverter, that is, the voltage value required by the inverter after being connected to the power grid is determined. In this way, the voltage value required by the inverter after being connected to the power grid can be obtained according to the first frequency difference and the first phase difference, that is, it is determined according to the difference between the operating parameters of the inverter and the power grid, so as to ensure the synchronization between the operating parameters of the inverter and the power grid after the inverter is connected to the power grid, and ensure the stable operation of the inverter.

[0062] In some embodiments, optionally, the output angular frequency of the inverter is determined based on the first frequency difference, the first phase difference and the natural frequency, including: superimposing the first frequency difference and the first phase difference to generate a superimposed value; inputting the superimposed value to a linear controller to generate an angular frequency adjustment amount of the inverter; and superimposing the angular frequency adjustment amount and the natural frequency to generate the output angular frequency.

[0063] In this embodiment, in the process of determining the output angular frequency of the inverter, the first frequency difference and the first phase difference can be firstly superimposed to generate a superposition value, so that the frequency difference and phase difference between the inverter and the power grid are superimposed to fully reflect the difference between the operating parameters of the inverter and the power grid.

[0064] Further, the superposition value is input into a linear controller (proportional integral controller, PI) to generate an angular frequency adjustment amount of the inverter. The superposition value of the first frequency difference and the first phase difference is calculated by the linear controller, so that the angular frequency adjustment amount required by the inverter during operation can be determined, that is, the angular frequency required to be increased based on the natural frequency of the inverter. Finally, the angular frequency adjustment amount of the inverter is superimposed on the natural frequency of the inverter to determine the output angular frequency required by the inverter after being connected to the power grid.

[0065] In some embodiments, optionally, the target voltage is determined based on the output angular frequency and the voltage amplitude, including: inputting the output angular frequency into an integrator to generate a real-time phase of the inverter; performing a sinusoidal calculation on the real-time phase; and superimposing the real-time phase after the sinusoidal calculation with the voltage amplitude to generate the target voltage.

[0066] In this embodiment, in the process of determining the target voltage of the inverter, that is, in the process of determining the target voltage required after the inverter is connected to the power grid, first, the output angular frequency required by the inverter can be input into the integrator, so as to perform an integral calculation on the output angular frequency required by the inverter, thereby generating the real-time phase of the inverter. It can be understood that according to the mathematical relationship between the angular frequency and the phase, the angular frequency can be converted into the phase by a sinusoidal calculation. Therefore, after the output angular frequency of the inverter is determined, the output angular frequency can be input into the integrator for integral calculation, thereby converting it into the real-time phase of the inverter.

[0067] Furthermore, the real-time phase of the inverter is sinusoidally calculated, and then the real-time phase after the sinusoidal calculation is superimposed with the voltage amplitude to generate the target voltage required by the inverter. It can be understood that after calculating the real-time phase of the inverter, the voltage adjustment amount after the inverter is connected to the grid can be obtained, and then the voltage adjustment amount is superimposed with the voltage amplitude of the inverter to obtain the target voltage required after the inverter is connected to the grid.

[0068] In some embodiments, optionally, before determining the output angular frequency of the inverter based on the first frequency difference, the first phase difference and the natural frequency, the control method also includes: inputting the first frequency difference to an amplifier to amplify the first frequency difference; and adjusting the first phase difference according to a preset adjustment algorithm.

[0069] In this embodiment, before determining the output angular frequency of the inverter based on the first frequency difference, the first phase difference and the natural frequency, the first frequency difference and the first phase difference need to be processed to improve the accuracy and efficiency of the output angular frequency calculation of the inverter, thereby improving the stability and accuracy of the inverter control process.

[0070] Specifically, the first frequency difference may be input into an amplifier to amplify the first frequency difference, thereby improving the accuracy of the first frequency difference in the calculation process, reducing the amount of calculation, and improving the calculation efficiency.

[0071] Furthermore, the first phase difference may be adjusted according to a preset adjustment algorithm, thereby further improving the accuracy of the angular frequency calculation of the inverter, and improving the stability and precision of the inverter control process.

[0072] In some embodiments, optionally, determining a first angular frequency and a first phase corresponding to the power grid according to the first voltage includes: inputting the first voltage into a digital phase-locked loop to generate the first angular frequency and the first phase.

[0073] In this embodiment, the first angular frequency and the first phase of the power grid can be calculated through a digital phase-locked loop. Specifically, after the first voltage of the power grid is obtained, the first voltage of the power grid can be input into the digital phase-locked loop. Through the calculation of the digital phase-locked loop, the first angular frequency and the first phase of the power grid can be calculated conveniently and quickly, thereby further improving the control efficiency of the inverter.

[0074] In some embodiments, optionally, the duty cycle of the switching element of the inverter is controlled according to the target voltage, including: obtaining the DC bus voltage of the inverter; calculating the DC bus voltage and the target voltage according to a pulse width modulation algorithm to determine the duty cycle of the switching element; and controlling the switching element to be turned on and off according to the duty cycle.

[0075] In this embodiment, a pulse width modulation (PWM) algorithm may be used to calculate the duty cycle of the switching device of the inverter, thereby determining the duty cycle of the switching device of the inverter.

[0076] Specifically, after determining the target voltage of the inverter, that is, after determining the target voltage required by the inverter after being connected to the power grid, the DC bus voltage of the inverter can be obtained first, and then the DC bus voltage and the target voltage are calculated according to the pulse width modulation algorithm to determine the duty cycle of the switching element of the inverter. Finally, the switching element is controlled to be switched on and off at the duty cycle, thereby controlling the inverter so that after the inverter is connected to the power grid, the operating parameters of the inverter and the power grid are synchronized to avoid a large impact on the inverter and ensure the stable operation of the inverter.

[0077] In a specific embodiment, the target voltage of the inverter can be determined by Figure 2 Specifically, firstly, the first voltage V grid Input to the digital phase-locked loop (DPLL) to generate the first angular frequency ω corresponding to the power grid grid and the first phase θ grid , then ω grid After amplification by the amplification factor K, θ grid The preset tuning algorithm is used to tune and obtain dθ, specifically:

[0078]

[0079] Where Δθ is the first phase θ grid With the second phase θ inv The difference between the two, further, the amplified ω grid The angular frequency adjustment dω of the inverter is obtained by superimposing dθ and dθ, and then inputting it into the PI controller to obtain the angular frequency adjustment dω of the inverter. Then dω and the natural frequency ω of the inverter are added together.n Superposition is performed to obtain the output angular frequency ω of the inverter inv .

[0080] Furthermore, inv Input to the integrator, perform integral calculation, and generate the real-time phase θ of the inverter inv , and then θ inv Perform sine calculation and convert the θ after sine calculation into inv The voltage amplitude V of the inverter amp Multiply them to get the target voltage V of the inverter inv Among them, θ grid and θ inv The value range of is [0,2π), so the value range of Δθ is (-2π,2π).

[0081] Furthermore, if Figure 3 , Figure 4 and Figure 5 As shown, through the inverter control method provided by the present application, after controlling the inverter for a period of time, the voltage, frequency and phase of the inverter are close to the voltage, frequency and phase of the power grid. At this time, connecting the inverter to the power grid can effectively avoid a large impact on the inverter and ensure the stable operation of the inverter.

[0082] In some embodiments, optionally, Figure 6 As shown, a control device 600 of an inverter is provided, wherein the inverter includes a plurality of switch elements, and the control device 600 of the inverter includes: an acquisition unit 602, used to acquire a first voltage of a power grid; a determination unit 604, used to determine a first angular frequency and a first phase corresponding to the power grid according to the first voltage; the acquisition unit 602 is also used to acquire a second angular frequency and a second phase of the inverter; the determination unit 604 is also used to determine a first frequency difference according to the first angular frequency and the second angular frequency; and to determine a first phase difference according to the first phase and the second phase; and to determine a target voltage of the inverter according to the first frequency difference and the first phase difference; a control unit 606, used to control the duty cycle of the switch element of the inverter according to the target voltage.

[0083] The control device 600 of the inverter provided in the present application first obtains the first voltage of the power grid before the inverter is connected to the power grid, and then determines the first angular frequency and the first phase of the power grid according to the first voltage, and then obtains the second angular frequency and the second phase of the inverter, and then can determine the first frequency difference according to the first angular frequency and the second angular frequency, and determine the first phase difference according to the first phase and the second phase, that is, determine the difference between the operating parameters of the inverter and the power grid. Then, the target voltage of the inverter is determined according to the first frequency difference and the first phase difference, and finally the duty cycle of the inverted switch is controlled according to the target voltage, so as to ensure the synchronization between the operating parameters of the inverter and the power grid, avoid a large impact on the inverter, and ensure the stable operation of the inverter.

[0084] Furthermore, the acquisition unit 602 is also used to obtain the natural frequency and voltage amplitude of the inverter; the determination unit 604 is specifically used to determine the output angular frequency of the inverter according to the first frequency difference, the first phase difference and the natural frequency; and determine the target voltage according to the output angular frequency and the voltage amplitude.

[0085] Furthermore, the determination unit 604 is specifically used to: superimpose the first frequency difference and the first phase difference to generate a superimposed value; input the superimposed value to the linear controller to generate an angular frequency adjustment amount of the inverter; and superimpose the angular frequency adjustment amount and the natural frequency to generate an output angular frequency.

[0086] Furthermore, the determination unit 604 is specifically used to: input the output angular frequency to the integrator to generate the real-time phase of the inverter; perform sine calculation on the real-time phase; and superimpose the real-time phase after the sine calculation with the voltage amplitude to generate the target voltage.

[0087] Furthermore, the inverter control device 600 also includes: an amplification unit, used to input the first frequency difference into an amplifier to amplify the first frequency difference; and a setting unit, used to set the first phase difference according to a preset setting algorithm.

[0088] Furthermore, the determining unit 604 is further specifically configured to: input the first voltage into a digital phase-locked loop to generate a first angular frequency and a first phase.

[0089] Furthermore, the acquisition unit 602 is also used to obtain the DC bus voltage of the inverter; the determination unit 604 is also used to calculate the DC bus voltage and the target voltage according to the pulse width modulation algorithm to determine the duty cycle of the switch element; the control unit 606 is specifically used to control the on and off of the switch element according to the duty cycle.

[0090] In some embodiments, optionally, Figure 7As shown, an electronic device 700 is proposed, including: a processor 702 and a memory 704, the memory 704 stores a program or instruction that can be run on the processor 702, and the program or instruction is executed by the processor 702 to implement the steps of the inverter control method in any of the above technical solutions. Therefore, the electronic device 700 has all the beneficial effects of the inverter control method in any of the above technical solutions, which will not be repeated here.

[0091] In some embodiments, optionally, a readable storage medium is provided, on which a program is stored. When the program is executed by a processor, the control method of the inverter in any of the above embodiments is implemented, thereby having all the beneficial technical effects of the control method of the inverter in any of the above embodiments.

[0092] The readable storage medium includes a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0093] It should be clarified that in the claims, specification and drawings of the present application, the term "multiple" refers to two or more than two. Unless otherwise clearly defined, the orientation or position relationship indicated by the terms "upper" and "lower" is based on the orientation or position relationship shown in the drawings, which is only for the purpose of more conveniently describing the present application and making the description process easier, rather than indicating or implying that the device or element referred to must have the specific orientation described, be constructed and operated in a specific orientation, so these descriptions cannot be understood as limitations on the present application; the terms "connect", "install", "fix" and the like should be understood in a broad sense. For example, "connection" can be a fixed connection between multiple objects, or a detachable connection between multiple objects, or an integral connection; it can be a direct connection between multiple objects, or an indirect connection between multiple objects through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood based on the specific circumstances of the above data.

[0094] In the claims, specification and drawings of the present application, the description of the terms "one embodiment", "some embodiments", "specific embodiments" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the claims, specification and drawings of the present application, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0095] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A control method for an inverter, characterized in that: The inverter includes a plurality of switch elements, and the control method includes: Acquiring a first voltage of a power grid; determining a first angular frequency and a first phase corresponding to the power grid according to the first voltage; Acquire a second angular frequency and a second phase of the inverter; determining a first frequency difference according to the first angular frequency and the second angular frequency; determining a first phase difference according to the first phase and the second phase; determining a target voltage of the inverter according to the first frequency difference and the first phase difference; According to the target voltage, a duty ratio of a switching element of the inverter is controlled.

2. The control method according to claim 1, characterized in that: The step of determining a target voltage of the inverter according to the first frequency difference and the first phase difference includes: Obtaining the natural frequency and voltage amplitude of the inverter; determining an output angular frequency of the inverter according to the first frequency difference, the first phase difference and the natural frequency; The target voltage is determined according to the output angular frequency and the voltage amplitude.

3. The control method according to claim 2, characterized in that: The step of determining the output angular frequency of the inverter according to the first frequency difference, the first phase difference and the natural frequency includes: Superimposing the first frequency difference and the first phase difference to generate a superimposed value; Inputting the superposition value into a linear controller to generate an angular frequency adjustment amount of the inverter; The angular frequency adjustment amount and the natural frequency are superimposed to generate the output angular frequency.

4. The control method according to claim 2, characterized in that: The step of determining the target voltage according to the output angular frequency and the voltage amplitude comprises: Inputting the output angular frequency into an integrator to generate a real-time phase of the inverter; Performing sinusoidal calculation on the real-time phase; The real-time phase after sinusoidal calculation is superimposed on the voltage amplitude to generate the target voltage.

5. The control method according to claim 2, characterized in that: Before determining the output angular frequency of the inverter according to the first frequency difference, the first phase difference and the natural frequency, the control method further includes: inputting the first frequency difference into an amplifier to amplify the first frequency difference; The first phase difference is adjusted according to a preset adjustment algorithm.

6. The control method according to any one of claims 1 to 5, characterized in that: The step of determining a first angular frequency and a first phase corresponding to the power grid according to the first voltage includes: The first voltage is input into a digital phase-locked loop to generate the first angular frequency and the first phase.

7. The control method according to any one of claims 1 to 5, characterized in that: The step of controlling the duty cycle of the switching element of the inverter according to the target voltage includes: Obtaining a DC bus voltage of the inverter; Calculating the DC bus voltage and the target voltage according to a pulse width modulation algorithm to determine the duty cycle of the switch element; The switch element is controlled to be turned on and off according to the duty cycle.

8. A control device for an inverter, characterized in that: The inverter includes a plurality of switch elements, and the control device includes: An acquisition unit, used for acquiring a first voltage of a power grid; a determining unit, configured to determine a first angular frequency and a first phase corresponding to the power grid according to the first voltage; The acquisition unit is also used to acquire a second angular frequency and a second phase of the inverter; The determining unit is further configured to determine a first frequency difference according to the first angular frequency and the second angular frequency; and determining a first phase difference according to the first phase and the second phase; and determining a target voltage of the inverter according to the first frequency difference and the first phase difference; A control unit is used to control the duty cycle of the switching element of the inverter according to the target voltage.

9. An electronic device, characterized in that: include: A processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A readable storage medium, characterized in that: The readable storage medium stores a program or an instruction, and when the program or the instruction is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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