Inverter control methods, control devices, electronic equipment, and readable storage media

Abstract

This application relates to the field of electronic power technology, and proposes a control method, control device, electronic device, and readable storage medium for an inverter. The inverter control method includes: acquiring a first voltage from the power grid; determining a first angular frequency and a first phase corresponding to the power grid based on the first voltage; acquiring a second angular frequency and a second phase of the inverter; determining a first frequency difference based on the first and second angular frequencies; determining a first phase difference based on the first and second phases; determining a target voltage for the inverter based on the first frequency difference and the first phase difference; and controlling the duty cycle of the inverter's switching components based on the target voltage. The inverter control method provided in this application can ensure synchronization between the operating parameters of the inverter and the power grid when the inverter is connected to the power grid, avoiding large impacts on the inverter and ensuring stable operation of the inverter.

Description

Technical Field

[0001] This application relates to the field of electronic power technology, and more specifically, to a control method, control device, electronic device, and readable storage medium for an inverter. Background Technology

[0002] In related technologies, when an inverter is operating off-grid, it typically needs to switch back to grid-connected operation after the grid returns to normal. To minimize the impact of this switching process, the inverter's operating parameters and the grid's operating parameters are usually synchronized before switching, ensuring that parameters such as voltage, frequency, and phase on the inverter side are essentially consistent with those on the grid side. However, since frequency tracking and phase adjustment are interdependent, phase errors may exist even when frequency tracking is accurate. When the phase error is small, it will increase again over time due to the presence of frequency errors. Therefore, improving the synchronization accuracy between the inverter's operating parameters and the grid's operating parameters has become a pressing technical problem. Summary of the Invention

[0003] This application aims to at least address the technical problem in the prior art where inverters are subject to significant impacts during grid connection due to asynchrony in operating parameters.

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

[0005] The second aspect of this application is to provide a control device for an inverter.

[0006] The third aspect of this application is to propose an electronic device.

[0007] The fourth aspect of this application is to propose a readable storage medium.

[0008] In view of the above, according to the first aspect of this application, a control method for an inverter is proposed, wherein the inverter includes a plurality of switching devices, and the control method for the inverter includes: acquiring a first voltage of the power grid; determining a first angular frequency and a first phase corresponding to the power grid based on the first voltage; acquiring 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 devices of the inverter based on the target voltage.

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

[0010] Before the inverter is connected to the grid, the first step is to obtain the grid's first voltage and determine the corresponding first angular frequency and first phase based on this voltage. Then, the inverter's second angular frequency and second phase are obtained. It's understandable that before connecting the inverter to the grid, to ensure synchronization between the inverter's operating parameters and the grid's operating parameters, it's necessary to first determine both the inverter's and grid's operating parameters, compare them to identify differences, and then synchronize the operating parameters based on these differences. This involves determining the grid's first angular frequency and first phase, and then determining the inverter's second angular frequency and second phase.

[0011] Furthermore, based on the first angular frequency and the second angular frequency, a first frequency difference is determined, and based on the first term and the second phase, a first phase difference is determined. 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 differences between them can be calculated separately. These are the first frequency difference and the first phase difference, which determine the differences between the operating parameters of the power grid and the inverter, thus enabling synchronization of operating parameters.

[0012] Furthermore, based on the first frequency difference and the first phase difference, the target voltage of the inverter is determined. Then, based on the target voltage, the duty cycle of the inverter's switching components is controlled, thereby synchronizing the inverter's operating parameters with those of the power grid. It can be understood that the inverter's operation is achieved by controlling the on / off states of multiple switching components within the inverter. In other words, during inverter operation, the on / off states of multiple switching components can be controlled according to the required duty cycle. The duty cycle of these switching components directly affects the inverter's voltage, frequency, and phase operating parameters.

[0013] Therefore, during inverter control, the target voltage required by the inverter is determined based on the first frequency difference and the first phase difference. This allows the determination of the target voltage based on the difference in operating parameters between the inverter and the grid. Subsequently, the duty cycle of the inverter's switching components is determined based on the target voltage, and finally, the inverter operation is controlled according to the determined duty cycle. In this way, while the inverter operates at the required target voltage, synchronization between the inverter's operating parameters and the grid's operating parameters is ensured. This avoids significant impacts on the inverter during grid connection, guaranteeing stable inverter operation.

[0014] The inverter control method provided in this application first acquires the first voltage of the grid before connecting the inverter to the grid. Then, based on the first voltage, it determines the first angular frequency and first phase of the grid. Next, it acquires the second angular frequency and second phase of the inverter. Then, it determines the first frequency difference based on the first and second angular frequencies, and the first phase difference based on the first and second phases, thus determining the difference between the operating parameters of the inverter and the grid. Then, it determines the target voltage of the inverter based on the first frequency difference and the first phase difference. Finally, it controls the duty cycle of the inverter's switching components based on the target voltage. This ensures synchronization between the operating parameters of the inverter and the grid, avoids significant impact on the inverter, and guarantees stable operation.

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

[0016] In some technical solutions, 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 the 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, the target voltage can be optionally determined based on the output angular frequency and voltage amplitude, including: inputting the output angular frequency to an integrator to generate the real-time phase of the inverter; performing a sine calculation on the real-time phase; and superimposing the sine-calculated real-time phase 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 further 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 tuning algorithm.

[0019] In some technical solutions, optionally, determining the first angular frequency and the first phase corresponding to the power grid based on the first voltage includes: inputting the first voltage to 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 inverter's switching components is controlled according to the target voltage, including: obtaining the inverter's DC bus voltage; calculating the DC bus voltage and the target voltage according to a pulse width modulation algorithm to determine the duty cycle of the switching components; and controlling the switching components to turn on and off according to the duty cycle.

[0021] According to a second aspect of this application, a control device for an inverter is provided, wherein the inverter includes a plurality of switching elements, and the control device for the inverter includes: an acquisition unit for acquiring a first voltage of the 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 further configured to acquire a second angular frequency and a second phase of the inverter; the determination unit is further configured to determine a first frequency difference based on the first angular frequency and the second angular frequency; and determine a first phase difference based on the first phase and the second phase; and determine a target voltage of the inverter based on the first frequency difference and the first phase difference; and a control unit for controlling the duty cycle of the switching elements of the inverter based on the target voltage.

[0022] The inverter control device provided in this application first acquires the first voltage of the grid before the inverter is connected to the grid. Then, it determines the first angular frequency and first phase of the grid based on the first voltage. Next, it acquires the second angular frequency and second phase of the inverter. Then, it determines the first frequency difference based on the first and second angular frequencies, and the first phase difference based on the first and second phases, thus determining the difference between the operating parameters of the inverter and the grid. Then, it determines the target voltage of the inverter based on the first frequency difference and the first phase difference. Finally, it controls the duty cycle of the inverter's switching components based on the target voltage. This ensures synchronization between the operating parameters of the inverter and the grid, avoids significant impact on the inverter, and guarantees stable operation.

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

[0024] In some technical solutions, optionally, the determining unit is further 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 the angular frequency adjustment amount of the inverter; and superimpose the angular frequency adjustment amount and the natural frequency to generate the output angular frequency.

[0025] In some technical solutions, optionally, the determining unit is further 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 sine calculation with the voltage amplitude to generate the target voltage.

[0026] In some technical solutions, the inverter control device may optionally include: an amplification unit for inputting the first frequency difference to an amplifier to amplify the first frequency difference; and a tuning unit for tuning the first phase difference according to a preset tuning algorithm.

[0027] In some technical solutions, optionally, the determining unit is further used to: input a first voltage to 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 acquire 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 switching device; the control unit is specifically used to control the switching device to turn on and off according to the duty cycle.

[0029] According to a third aspect of this application, an electronic device is proposed, comprising: a processor and a memory, wherein the memory stores a program or instructions executable on the processor, and when the program or instructions are executed by the processor, implement the steps of the inverter control method of any of the above-described technical solutions. Therefore, this electronic device possesses all the beneficial effects of the inverter control method of any of the above-described technical solutions, which will not be elaborated further here.

[0030] According to a fourth aspect of this application, a readable storage medium is proposed, on which a program or instructions are stored, which, when executed by a processor, implement the inverter control method as described in any of the above-described technical solutions. Therefore, this readable storage medium possesses all the beneficial effects of the inverter control method in any of the above-described technical solutions, which will not be elaborated further here.

[0031] Additional aspects and advantages of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description

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

[0033] Figure 1 A flowchart illustrating the control method of an inverter according to an embodiment of this application is shown;

[0034] Figure 2 A circuit diagram is shown illustrating the control method of the inverter according to an embodiment of this application;

[0035] Figure 3 The voltage curves during the control process of the inverter according to an embodiment of this application are shown;

[0036] Figure 4 The frequency curves during the control process of the inverter according to an embodiment of this application are shown;

[0037] Figure 5 The phase curves during the control process of the inverter according to an embodiment of this application are shown;

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

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

[0040] Figure label:

[0041] 600 Control device for inverter, 602 Acquisition unit, 604 Determination unit, 606 Control unit, 700 Electronic device, 702 Processor, 704 Memory. Detailed Implementation

[0042] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

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

[0044] The following is combined Figures 1 to 7 The present application provides a detailed description of the inverter control method, control device, electronic device, and readable storage medium provided in the embodiments of this application through specific implementation methods and application scenarios.

[0045] like Figure 1 As shown, an embodiment of this application provides a control method for an inverter, wherein the inverter includes multiple switching devices, and the control method for the inverter includes:

[0046] Step 102: Obtain the first voltage of the power grid;

[0047] Step 104: Determine the first angular frequency and first phase corresponding to the power grid based on the first voltage;

[0048] Step 106: Obtain the second angular frequency and second phase of the inverter;

[0049] Step 108: Determine the first frequency difference based on the first angular frequency and the second angular frequency;

[0050] Step 110: Determine the first phase difference based on the first phase and the second phase;

[0051] Step 112: Determine the target voltage of the inverter based on the first frequency difference and the first phase difference;

[0052] Step 114: Control the duty cycle of the inverter's switching components according to the target voltage.

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

[0054] Before the inverter is connected to the grid, the first step is to obtain the grid's first voltage and determine the corresponding first angular frequency and first phase based on this voltage. Then, the inverter's second angular frequency and second phase are obtained. It's understandable that before connecting the inverter to the grid, to ensure synchronization between the inverter's operating parameters and the grid's operating parameters, it's necessary to first determine both the inverter's and grid's operating parameters, compare them to identify differences, and then synchronize the operating parameters based on these differences. This involves determining the grid's first angular frequency and first phase, and then determining the inverter's second angular frequency and second phase.

[0055] Furthermore, based on the first angular frequency and the second angular frequency, a first frequency difference is determined, and based on the first term and the second phase, a first phase difference is determined. 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 differences between them can be calculated separately. These are the first frequency difference and the first phase difference, which determine the differences between the operating parameters of the power grid and the inverter, thus enabling synchronization of operating parameters.

[0056] Furthermore, based on the first frequency difference and the first phase difference, the target voltage of the inverter is determined. Then, based on the target voltage, the duty cycle of the inverter's switching components is controlled, thereby synchronizing the inverter's operating parameters with those of the power grid. It can be understood that the inverter's operation is achieved by controlling the on / off states of multiple switching components within the inverter. In other words, during inverter operation, the on / off states of multiple switching components can be controlled according to the required duty cycle. The duty cycle of these switching components directly affects the inverter's voltage, frequency, and phase operating parameters.

[0057] Therefore, during inverter control, the target voltage required by the inverter is determined based on the first frequency difference and the first phase difference. This allows the determination of the target voltage based on the difference in operating parameters between the inverter and the grid. Subsequently, the duty cycle of the inverter's switching components is determined based on the target voltage, and finally, the inverter operation is controlled according to the determined duty cycle. In this way, while the inverter operates at the required target voltage, synchronization between the inverter's operating parameters and the grid's operating parameters is ensured. This avoids significant impacts on the inverter during grid connection, guaranteeing stable inverter operation.

[0058] The inverter control method provided in this application first acquires the first voltage of the grid before connecting the inverter to the grid. Then, based on the first voltage, it determines the first angular frequency and first phase of the grid. Next, it acquires the second angular frequency and second phase of the inverter. Then, it determines the first frequency difference based on the first and second angular frequencies, and the first phase difference based on the first and second phases, thus determining the difference between the operating parameters of the inverter and the grid. Then, it determines the target voltage of the inverter based on the first frequency difference and the first phase difference. Finally, it controls the duty cycle of the inverter's switching components based on the target voltage. This ensures synchronization between the operating parameters of the inverter and the grid, avoids significant impact on the inverter, and guarantees stable operation.

[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 inverter's natural frequency and voltage amplitude; determining the inverter's output angular frequency 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 determining the target voltage of the inverter, the inverter's inherent frequency and voltage amplitude can be obtained first. It can be understood that the inverter's inherent frequency and voltage amplitude are determined based on the inverter's own hardware parameters. That is, the inherent frequency and voltage amplitude are characteristics of the inverter itself and can be directly obtained based on the inverter's hardware parameters.

[0061] Furthermore, after determining the first frequency difference between the first and second angular frequencies, and the first phase difference between the first and second phases, the output angular frequency of the inverter can be determined based on the first frequency difference, the first phase difference, and the inverter's inherent frequency. This is the output angular frequency required by the inverter after connection to the grid. Further, the target voltage of the inverter can be determined based on the required output angular frequency and the inverter's voltage amplitude; that is, the voltage value required by the inverter after connection to the grid. Thus, the voltage value required by the inverter after grid connection can be obtained based on the first frequency difference and the first phase difference, i.e., determined based on the difference between the operating parameters of the inverter and the grid. This ensures synchronization between the operating parameters of the inverter and the grid after grid connection, guaranteeing stable inverter operation.

[0062] In some embodiments, optionally, determining the output angular frequency of the inverter based on 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 superimposed value to a linear controller to generate an angular frequency adjustment amount for 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 superimposed to generate a superimposed value, thereby superimposing the frequency difference and phase difference between the inverter and the grid to fully reflect the difference between the operating parameters of the inverter and the grid.

[0064] Furthermore, the superimposed value is input to the proportional integral controller (PI) to generate the inverter's angular frequency adjustment. By calculating the superimposed value of the first frequency difference and the first phase difference using the linear controller, the required angular frequency adjustment during inverter operation can be determined—that is, the angular frequency increase needed on top of the inverter's natural frequency. Finally, by superimposing the inverter's angular frequency adjustment with the inverter's natural frequency, the required output angular frequency of the inverter after connection to the grid can be determined.

[0065] In some embodiments, optionally, determining the target voltage based on the output angular frequency and voltage amplitude includes: inputting the output angular frequency to an integrator to generate the real-time phase of the inverter; performing a sine calculation on the real-time phase; and superimposing the sine-calculated real-time phase with the voltage amplitude to generate the target voltage.

[0066] In this embodiment, during the process of determining the target voltage of the inverter—that is, the target voltage required after the inverter is connected to the grid—the required output angular frequency of the inverter can first be input to the integrator. The required output angular frequency is then integrated to generate the real-time phase of the inverter. It can be understood that, based on the mathematical relationship between angular frequency and phase, the angular frequency can be converted into phase using a sine wave calculation. Therefore, after determining the output angular frequency of the inverter, it can be input to the integrator for integration, 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 calculated real-time phase is superimposed with the voltage amplitude to generate the target voltage required by the inverter. In essence, after calculating the real-time phase of the inverter, the voltage regulation amount after the inverter is connected to the grid can be obtained. Then, this voltage regulation amount is superimposed with the inverter's voltage amplitude 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 further 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 tuning algorithm.

[0069] In this embodiment, before determining the inverter's output angular frequency 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 inverter's output angular frequency calculation, thereby improving the stability and precision of the inverter control process.

[0070] Specifically, the first frequency difference can be input to an amplifier to amplify it, 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 can be tuned according to a preset tuning algorithm, thereby further improving the accuracy of the inverter's angular frequency calculation and 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 based on a first voltage includes: inputting the first voltage to a digital phase-locked loop to generate the first angular frequency and the first phase.

[0073] In this embodiment, the first angular frequency and first phase of the power grid can be calculated using a digital phase-locked loop (PLL). Specifically, after obtaining the first voltage of the power grid, the first voltage of the power grid can be input into the PLL. Through the calculation of the PLL, the first angular frequency and 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, controlling the duty cycle of the inverter's switching components according to the target voltage includes: acquiring the inverter's DC bus voltage; calculating the duty cycle of the switching components based on the DC bus voltage and the target voltage using a pulse width modulation algorithm; and controlling the switching components to turn on and off according to the duty cycle.

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

[0076] Specifically, after determining the target voltage of the inverter, that is, the target voltage required by the inverter after connecting to the grid, the DC bus voltage of the inverter can be obtained first. Then, according to the pulse width modulation algorithm, the DC bus voltage and the target voltage are calculated to determine the duty cycle of the inverter's switching devices. Finally, the switching devices are controlled to turn on and off at this duty cycle, thereby controlling the inverter to ensure that the operating parameters of the inverter and the grid are synchronized after the inverter is connected to the grid, avoiding large impacts on the inverter and ensuring the stable operation of the inverter.

[0077] In one specific embodiment, the target voltage of the inverter can be obtained through, for example... Figure 2 The circuit diagram shown is used to determine the circuit. Specifically, the first voltage V of the power grid is first... grid The input is fed into a 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 being amplified by the magnification factor K, θ grid The tuning is performed using a preset tuning algorithm to obtain dθ, specifically:

[0078]

[0079] Where Δθ is the first phase θ grid With the second phase θ inv The difference between them, further, will be the amplified ω grid The angular frequency adjustment dω of the inverter is obtained by superimposing dω with dθ and then inputting it to the PI controller. Then, dω is combined with the inverter's natural frequency ω.n By superimposing these values, the output angular frequency ω of the inverter can be obtained. inv .

[0080] Furthermore, ω inv The input is fed into the integrator for integration calculation, generating the real-time phase θ of the inverter. inv , then θ inv Perform sine calculation, and then calculate θ. inv With the voltage amplitude V of the inverter amp Multiplying the two values ​​yields the target voltage V of the inverter. inv Where θ grid and θ inv The range of values ​​for is [0, 2π), so the range of values ​​for Δθ is (-2π, 2π).

[0081] Furthermore, such as Figure 3 , Figure 4 and Figure 5 As shown, after the inverter is controlled for a period of time using the control method provided in this application, the voltage, frequency, and phase of the inverter are close to those of the grid. At this time, connecting the inverter to the grid can effectively avoid a large impact on the inverter and ensure the stable operation of the inverter.

[0082] In some embodiments, optionally, such as Figure 6 As shown, a control device 600 for an inverter is provided. The inverter includes multiple switching devices. The control device 600 includes: an acquisition unit 602 for acquiring a first voltage of the power grid; a determination unit 604 for determining a first angular frequency and a first phase corresponding to the power grid based on the first voltage; the acquisition unit 602 is further used to acquire a second angular frequency and a second phase of the inverter; the determination unit 604 is further 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; and a control unit 606 for controlling the duty cycle of the switching devices of the inverter based on the target voltage.

[0083] The inverter control device 600 provided in this application first acquires the first voltage of the grid before the inverter is connected to the grid. Then, it determines the first angular frequency and first phase of the grid based on the first voltage. Next, it acquires the second angular frequency and second phase of the inverter. Then, it determines the first frequency difference based on the first and second angular frequencies, and the first phase difference based on the first and second phases, thus determining the difference between the operating parameters of the inverter and the grid. Then, it determines the target voltage of the inverter based on the first frequency difference and the first phase difference. Finally, it controls the duty cycle of the inverter's switching components based on the target voltage. This ensures synchronization between the operating parameters of the inverter and the grid, avoids significant impact on the inverter, and guarantees stable operation of the inverter.

[0084] Furthermore, the acquisition unit 602 is also used to acquire the inverter's inherent frequency and voltage amplitude; the determination unit 604 is specifically used to determine the inverter's output angular frequency based on the first frequency difference, the first phase difference and the inherent frequency; and to determine the target voltage based on the output angular frequency and voltage amplitude.

[0085] Furthermore, the determining 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 the angular frequency adjustment amount of the inverter; and superimpose the angular frequency adjustment amount and the natural frequency to generate the output angular frequency.

[0086] Furthermore, the determining 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 sine calculation with the voltage amplitude to generate the target voltage.

[0087] Furthermore, the inverter control device 600 also includes: an amplification unit for inputting the first frequency difference to an amplifier to amplify the first frequency difference; and a tuning unit for tuning the first phase difference according to a preset tuning algorithm.

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

[0089] Furthermore, the acquisition unit 602 is also used to acquire 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 switching device; the control unit 606 is specifically used to control the switching device to turn on and off according to the duty cycle.

[0090] In some embodiments, optionally, such as Figure 7As shown, an electronic device 700 is proposed, comprising a processor 702 and a memory 704. The memory 704 stores programs or instructions that can run on the processor 702. When the program or instructions are executed by the processor 702, they implement the steps of the inverter control method of any of the above-described technical solutions. Therefore, the electronic device 700 possesses all the beneficial effects of the inverter control method of any of the above-described technical solutions, which will not be elaborated further here.

[0091] In some embodiments, optionally, a readable storage medium is provided having a program stored thereon, which, when executed by a processor, implements the inverter control method as described in any of the above embodiments, and thus has all the beneficial technical effects of the inverter control method described in any of the above embodiments.

[0092] Among them, readable storage media include read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0093] It should be clarified that in the claims, description, and accompanying drawings of this application, the term "multiple" refers to two or more objects. Unless otherwise explicitly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description process, not to indicate or imply that the device or element referred to must have the described specific orientation, or be constructed and operated in a specific orientation. Therefore, these descriptions should not be construed as limitations on this application. The terms "connection," "installation," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection between multiple objects, 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 those skilled in the art, the specific meaning of the above terms in this application can be understood based on the specific circumstances of the above data.

[0094] In the claims, description, and accompanying drawings of this application, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In the claims, description, and accompanying drawings of this application, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0095] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A control method of an inverter, characterized by, The inverter comprises a plurality of switching elements, and the control method comprises: 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; obtaining 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; controlling a duty cycle of a switching element of the inverter according to the target voltage; the determining of the target voltage of the inverter according to the first frequency difference and the first phase difference comprises: obtaining an inherent frequency and a 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 inherent frequency; determining the target voltage according to the output angular frequency and the voltage amplitude; the determining of the output angular frequency of the inverter according to the first frequency difference, the first phase difference and the inherent frequency comprises: superimposing the first frequency difference and the first phase difference to generate a superimposed value; inputting the superimposed value into a linear controller to generate an angular frequency adjustment amount of the inverter; superimposing the angular frequency adjustment amount and the inherent frequency to generate the output angular frequency; wherein the linear controller is a PI controller.

2. The control method according to claim 1, characterized by, the determining of 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 sine calculation on the real-time phase; superimposing the real-time phase after sine calculation and the voltage amplitude to generate the target voltage.

3. The control method according to claim 1, characterized by, Before the determining of the output angular frequency of the inverter according to the first frequency difference, the first phase difference and the inherent frequency, the control method further comprises: inputting the first frequency difference into an amplifier to amplify the first frequency difference; adjusting the first phase difference according to a preset adjustment algorithm.

4. The control method according to any one of claims 1 to 3, characterized by, the determining of the first angular frequency and the first phase corresponding to the power grid according to the first voltage comprises: inputting the first voltage into a digital phase-locked loop to generate the first angular frequency and the first phase.

5. The control method according to any one of claims 1 to 3, characterized by, the controlling of the duty cycle of the switching element of the inverter according to the target voltage comprises: obtaining a direct-current bus voltage of the inverter; calculating the direct-current bus voltage and the target voltage according to a pulse width modulation algorithm to determine the duty cycle of the switching element; controlling the switching element to turn on and off according to the duty cycle.

6. A control device of an inverter, characterized by comprising: The inverter comprises a plurality of switching elements, and the control device comprises: an obtaining unit, configured to obtain 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 obtaining unit is further configured to obtain 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 determine a first phase difference according to the first phase and the second phase; and determine a target voltage of the inverter according to the first frequency difference and the first phase difference; a control unit configured to control a duty cycle of a switching element of the inverter according to the target voltage; the acquisition unit is further configured to acquire an inherent frequency and a voltage amplitude of the inverter; the determination unit is further configured to determine an output angular frequency of the inverter according to the first frequency difference, the first phase difference and the inherent frequency, and determine the target voltage according to the output angular frequency and the voltage amplitude; the determination unit is further configured 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, and superimpose the angular frequency adjustment amount and the inherent frequency to generate the output angular frequency. The linear controller is a PI controller.

7. An electronic device, comprising: comprising: a processor and a memory, the memory storing programs or instructions executable on the processor, the programs or instructions being executed by the processor to implement the steps of the method of any one of claims 1 to 5.

8. A readable storage medium, characterized by, programs or instructions are stored on the readable storage medium, and the programs or instructions are executed by the processor to implement the steps of the method of any one of claims 1 to 5.

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