Output power control method and device of inverter, equipment and storage medium

Abstract

The invention relates to the technical field of inverter control, and discloses an inverter output power control method and device, equipment and a storage medium. The method comprises the following steps: performing power frequency fundamental wave extraction and multi-band band-pass filtering on acquired voltage and current sampling data; performing phase compensation, first coordinate transformation and positive and negative sequence decoupling operation on the filtered fundamental wave principal component data; on the basis of a synchronous phase angle and a power grid fundamental wave frequency obtained by positive and negative sequence decoupling operation, carrying out second coordinate transformation, moving average and harmonic power delay difference operation on three-phase current and voltage data of an alpha-beta coordinate system; performing multi-level power calculation, power capacity distribution, error characteristic evaluation and decoupling operation on the inversion fundamental component and the inversion harmonic component subjected to the difference operation; and performing output signal modulation on the inversion power control quantity of the decoupling operation based on the fundamental wave synchronization phase angle, and generating a power control result. According to the invention, the control performance of the inverter on the output power in actual operation is improved.

Description

Technical Field

[0001] The present invention relates to the field of inverter control technology, and in particular to an inverter output power control method, device, equipment and storage medium. Background Art

[0002] As a key bridge between renewable energy and the power grid, the grid-connected inverter's output power control technology is crucial to the stable operation of the entire power system. However, the existing inverter output power control methods have two main challenges.

[0003] On the one hand, traditional inverter power control methods mainly adopt PI control or PR control strategies, but these methods have limitations when dealing with complex power grid environments. Especially when the power grid has high harmonic content and severe imbalance, the control accuracy and dynamic response performance are difficult to meet the requirements. On the other hand, the existing control methods often ignore the various disturbance factors in the system, such as load mutation, power grid fluctuation, sampling delay, etc., and do not fully consider the capacity constraints and power distribution characteristics of the inverter itself, resulting in unsatisfactory control effects. That is, the existing inverter output power control methods fail to effectively deal with the various disturbance factors in the complex power grid environment, and do not fully consider the system characteristics and operation constraints, resulting in poor control performance of the inverter on the output power in actual operation. Summary of the invention

[0004] The main purpose of the present invention is to solve the problem that the existing inverter output power control method fails to effectively deal with various disturbance factors in a complex power grid environment, and does not fully consider system characteristics and operation constraints, resulting in poor control performance of the inverter on the output power in actual operation.

[0005] The first aspect of the present invention provides an output power control method of an inverter, the output power control method of the inverter comprising: acquiring voltage and current sampling data at the output end of a target inverter, and performing power frequency fundamental wave extraction and multi-band bandpass filtering on the voltage and current sampling data to obtain fundamental wave main component data; performing phase compensation and a first coordinate transformation on the fundamental wave main component data to obtain three-phase current and voltage data of an αβ coordinate system, and performing positive and negative sequence decoupling operations on the three-phase current and voltage data of the αβ coordinate system to obtain a fundamental wave synchronous phase angle and a grid fundamental wave frequency; based on the fundamental wave synchronous phase angle, performing a second coordinate transformation on the three-phase current and voltage data of the αβ coordinate system to obtain a dq axis voltage The invention relates to a method for obtaining a first inverter and a second inverter for generating a first power supply of the target inverter. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter harmonic component. The first inverter comprises a first inverter and a second inverter power control quantity. The first inverter comprises a first inverter and a second inverter power control quantity. The first inverter comprises a first inverter and a second inverter power control quantity. The first inverter comprises a first inverter and a second inverter power control quantity.

[0006] Optionally, in a first implementation of the first aspect of the present invention, the power frequency fundamental wave extraction and multi-band bandpass filtering of the voltage and current sampling data to obtain fundamental wave main component data include: performing power frequency period calculation on the voltage and current sampling data to obtain frequency band distribution characteristics, and performing filter bandwidth calculation on the frequency band distribution characteristics to obtain filter parameters of each frequency band; based on the frequency band filter parameters, performing sub-band filtering on the voltage and current sampling data to obtain fundamental wave frequency band signals, and performing signal-to-noise ratio evaluation on the fundamental wave frequency band signals to obtain signal-to-noise ratio characteristic data; based on the signal-to-noise ratio characteristic data, performing signal-to-noise ratio evaluation on the fundamental wave frequency band signals The signal is subjected to noise reduction and signal reconstruction to obtain voltage and current sampling data after preliminary filtering, and the power frequency cycle detection is performed on the voltage and current sampling data after preliminary filtering to obtain the inverter fundamental wave cycle, and based on the inverter fundamental wave cycle, the fundamental wave mean value is calculated on the voltage and current sampling data after preliminary filtering to obtain the fundamental wave signal main component, and the fundamental wave signal main component is subjected to zero-crossing detection to obtain fundamental wave phase data; based on the fundamental wave phase data, the inverter fundamental wave amplitude within the inverter fundamental wave cycle is calculated, and based on the inverter fundamental wave amplitude, the fundamental wave signal main component is subjected to amplitude correction and phase correction to obtain fundamental wave main component data.

[0007] Optionally, in a second implementation method of the first aspect of the present invention, the phase compensation and the first coordinate transformation are performed on the fundamental main component data to obtain the three-phase current and voltage data of the αβ coordinate system, including: performing difference calculation on two adjacent points in the fundamental main component data to obtain a sampling interval characteristic, and based on the sampling interval characteristic, performing delay calculation on the fundamental main component data to obtain an inverter sampling delay; performing a proportional operation on the inverter sampling delay and the inverter fundamental period to obtain a phase compensation value, and based on the phase compensation value, performing phase adjustment on the fundamental main component data to obtain pre-compensation data; performing phase difference calculation on the three-phase signal in the pre-compensation data to obtain a phase deviation value between the three phases, and based on the phase deviation value, performing phase calibration on the pre-compensation data to obtain delay-eliminated three-phase voltage and current data; performing Clarke transformation on the delay-eliminated three-phase voltage and current data to obtain three-phase current and voltage data of the αβ coordinate system.

[0008] Optionally, in a third implementation method of the first aspect of the present invention, the positive and negative sequence decoupling operation is performed on the three-phase current and voltage data of the αβ coordinate system to obtain the fundamental synchronous phase angle and the fundamental frequency of the power grid, including: performing phase delay of a preset delay angle on the three-phase current and voltage data of the αβ coordinate system to obtain orthogonal current and voltage data, and based on the orthogonal current and voltage data, performing signal addition and subtraction calculations on the three-phase current and voltage data of the αβ coordinate system to obtain initial positive and negative sequence components; performing instantaneous amplitude calculations on the initial positive and negative sequence components to obtain positive and negative sequence amplitude data, and performing phase detection on the positive sequence components in the initial positive and negative sequence components to obtain instantaneous phase change; performing forward integration calculations on the positive and negative sequence amplitude data to obtain the fundamental synchronous phase angle, and performing mean calculations on the instantaneous phase change to obtain the fundamental frequency of the power grid.

[0009] Optionally, in a fourth implementation method of the first aspect of the present invention, the dq-axis voltage and current data are subjected to sliding average and delayed difference operations of harmonic power based on the fundamental frequency of the power grid to obtain an inverter fundamental component and an inverter harmonic component, including: calculating the sliding window length corresponding to the fundamental frequency of the power grid, and performing moving summation calculations on the dq-axis voltage and current data based on the sliding window length to obtain a sliding cumulative value; performing mean calculations on the sliding cumulative value based on the sliding window length to obtain an initial fundamental component, and using the dq-axis voltage and current data to perform a difference on the fundamental average component to obtain an initial harmonic component; performing sub-harmonic amplitude calculations on the initial harmonic component to obtain data of each sub-harmonic, and performing root mean square calculations on the initial fundamental component and each sub-harmonic data to obtain an inverter fundamental component and an inverter harmonic component.

[0010] Optionally, in a fifth implementation of the first aspect of the present invention, based on the rated apparent power capacity corresponding to the target inverter, multi-level power calculation and power capacity allocation are performed on the inverter fundamental component and the inverter harmonic component to obtain a fundamental power characteristic quantity and a compensation power characteristic quantity, including: multiplying the dq axis voltage and the dq axis current in the inverter fundamental component to obtain fundamental active power and fundamental reactive power, and multiplying the dq axis voltage and the dq axis current in the inverter harmonic component to obtain a fundamental active power and a fundamental reactive power. Calculate the harmonic active power and the harmonic reactive power, and calculate the fundamental apparent power between the fundamental active power and the fundamental reactive power; compare the rated apparent power capacity corresponding to the target inverter with the fundamental apparent power to obtain the remaining capacity of the inverter, and perform compensation allocation calculation on the harmonic active power and the harmonic reactive power based on the remaining capacity of the inverter to obtain the compensated power characteristic quantity, and perform power extreme value limiting on the fundamental active power and the fundamental reactive power to obtain the fundamental power characteristic quantity.

[0011] Optionally, in a sixth implementation method of the first aspect of the present invention, the error characteristic evaluation and decoupling operation are performed on the fundamental power characteristic quantity and the compensation power characteristic quantity to obtain the inverter power control quantity, including: performing error calculation of the actual inverter output power on the fundamental power characteristic quantity and the compensation power characteristic quantity to obtain the inverter power deviation quantity, and performing power control gain calculation on the inverter power deviation quantity based on the inverter fundamental component and the inverter harmonic component to obtain the initial power control quantity; performing dq-axis control value conversion on the initial power control quantity based on the inverter fundamental component and the inverter harmonic component to obtain the dq-axis decomposition quantity, and superimposing the corresponding fundamental data and harmonic data in the dq-axis decomposition quantity to obtain the composite power control quantity; performing power comparison and power limitation on the composite power control quantity and the rated apparent power capacity corresponding to the target inverter to obtain the limiting control quantity, and using the limiting control quantity to perform a superposition operation on the original power control quantity corresponding to the target inverter to obtain the inverter power control quantity.

[0012] The second aspect of the present invention provides an output power control device for an inverter, the output power control device for the inverter comprising: a fundamental wave extraction module, used to obtain voltage and current sampling data at the output end of a target inverter, and perform power frequency fundamental wave extraction and multi-band bandpass filtering on the voltage and current sampling data to obtain fundamental wave main component data; a first transformation module, used to perform phase compensation and a first coordinate transformation on the fundamental wave main component data to obtain three-phase current and voltage data of an αβ coordinate system, and perform positive and negative sequence decoupling operations on the three-phase current and voltage data of the αβ coordinate system to obtain a fundamental wave synchronous phase angle and a fundamental wave frequency of a power grid; a second transformation module, used to perform a second coordinate transformation on the three-phase current and voltage data of the αβ coordinate system based on the fundamental wave synchronous phase angle to obtain d The invention relates to a power grid which is composed of a plurality of inverters, a power grid which is composed of a plurality of inverters and a plurality of power grids, and a plurality of inverters which are composed of a plurality of inverters. The power grid which is composed of a plurality of inverters, a power grid which is composed of a plurality of inverters and a plurality of power grids, and a plurality of inverters which are composed of a plurality of inverters. The power grid which is composed of a plurality of inverters, a power grid which is composed of a plurality of inverters, and a plurality of power grids, and a plurality of inverters which are composed of a plurality of inverters. The power grid which is composed of a plurality of inverters, a power grid which is composed of a plurality of inverters, and a plurality of power grids, and a plurality of inverters which are composed of a plurality of inverters. The power grid which is composed of a plurality of inverters, a power grid which is composed of a plurality of inverters, and a plurality of power grids, and a plurality of inverters which are composed of a plurality of inverters.

[0013] The third aspect of the present invention provides an output power control device of an inverter, comprising: a memory and at least one processor, wherein the memory stores instructions; the at least one processor calls the instructions in the memory so that the output power control device of the inverter performs each step of the above-mentioned output power control method of the inverter.

[0014] A fourth aspect of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores instructions, which, when executed on a computer, enable the computer to execute the various steps of the inverter output power control method described above.

[0015] The output power control method, device, equipment and storage medium of the above-mentioned inverter. In the embodiment of the present invention, the voltage and current sampling data of the output end of the target inverter are obtained, and the power frequency fundamental wave extraction and multi-band bandpass filtering are performed on the voltage and current sampling data to obtain the fundamental wave main component data; the phase compensation and the first coordinate transformation are performed on the fundamental wave main component data to obtain the three-phase current and voltage data of the αβ coordinate system, and the positive and negative sequence decoupling operation is performed on the three-phase current and voltage data of the αβ coordinate system to obtain the fundamental wave synchronous phase angle and the fundamental wave frequency of the power grid; based on the fundamental wave synchronous phase angle, the second coordinate transformation is performed on the three-phase current and voltage data of the αβ coordinate system to obtain the dq axis voltage and current data, and based on the fundamental wave frequency of the power grid, The dq-axis voltage and current data are subjected to sliding average and delayed difference calculation of harmonic power to obtain an inverter fundamental component and an inverter harmonic component; based on the rated apparent power capacity corresponding to the target inverter, multi-level power calculation and power capacity allocation are performed on the inverter fundamental component and the inverter harmonic component to obtain a fundamental power characteristic quantity and a compensation power characteristic quantity, and error characteristic evaluation and decoupling calculation are performed on the fundamental power characteristic quantity and the compensation power characteristic quantity to obtain an inverter power control quantity; based on the fundamental synchronization phase angle, the inverter power control quantity is subjected to output signal modulation to generate an output power control result of the target inverter. Compared with the prior art, the present application obtains the fundamental main component characteristics by sampling and multi-band filtering the voltage and current data at the output end of the target inverter, and then performs phase compensation and coordinate transformation to obtain three-phase data in the αβ coordinate system and realize positive and negative sequence decoupling, and obtains the fundamental synchronous phase angle and grid frequency; then the data is converted to the dq coordinate system based on the synchronous phase angle, and the fundamental and harmonic components are separated by sliding average and delay difference calculation; then the power calculation and capacity allocation of these components are performed, and the power control amount is obtained by combining error evaluation and decoupling operation; finally, the signal modulation output control result is performed based on the synchronous phase angle. Through hierarchical signal processing and control calculation, the problem of precise control of the inverter output power is solved, especially in terms of harmonic separation and power distribution, the dynamic characteristics of the inverter are fully considered, the control accuracy is effectively improved, and a multi-level decoupling and error compensation strategy is adopted, which not only ensures the output power quality, but also enhances the stability of the inverter output power, thereby realizing efficient and precise control of the inverter output power as a whole.

[0016] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0017] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of a first embodiment of an output power control method of an inverter according to an embodiment of the present invention; Figure 2 Schematic diagram of an embodiment of an output power control device of an inverter in an embodiment of the present invention; Figure 3 The figure is a schematic diagram of an embodiment of an output power control device of an inverter in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The terms "including" and "having" and any variations thereof mentioned in the embodiments of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device end including a series of steps or units is not limited to the listed steps or units, but may optionally include other steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or device ends.

[0021] To facilitate understanding of this embodiment, the specific process of the embodiment of the present invention is described below. Figure 1 , a first embodiment of the output power control method of the inverter in the embodiment of the present invention includes: 101. Acquire voltage and current sampling data at the output end of the target inverter, and perform power frequency fundamental wave extraction and multi-band bandpass filtering on the voltage and current sampling data to obtain fundamental wave main component data; The embodiments of the present application can acquire and process relevant data based on artificial intelligence technology. Artificial Intelligence (AI) is the theory, method, technology and application system that uses digital computers or machines controlled by digital computers to simulate, extend and expand human intelligence, perceive the environment, acquire knowledge and use knowledge to obtain the best results.

[0022] AI basic technologies generally include sensors, dedicated AI chips, cloud computing, distributed storage, big data processing technology, operation / interaction systems, mechatronics, etc. AI software technologies mainly include computer vision technology, robotics technology, biometrics technology, speech processing technology, natural language processing technology, and machine learning / deep learning.

[0023] In this embodiment, the target inverter here refers to a device that converts a DC power supply into a corresponding AC power, which is not limited to a grid-connected inverter that is a key bridge between new energy and the power grid, but can also be other electrical equipment that needs to convert DC power into AC power; the power frequency cycle of the voltage and current sampling data is calculated to obtain a frequency band distribution feature, and the filter bandwidth of the frequency band distribution feature is calculated to obtain filter parameters of each frequency band; based on the frequency band filter parameters, the voltage and current sampling data is subjected to frequency band filtering to obtain a fundamental frequency band signal, and the signal-to-noise ratio of the fundamental frequency band signal is evaluated to obtain signal-to-noise ratio characteristic data; based on the signal-to-noise ratio characteristic data, The fundamental frequency band signal is subjected to noise reduction and signal reconstruction to obtain voltage and current sampling data after preliminary filtering, and the power frequency cycle detection is performed on the voltage and current sampling data after preliminary filtering to obtain the inverter fundamental cycle. Based on the inverter fundamental cycle, the fundamental mean value of the voltage and current sampling data after preliminary filtering is calculated to obtain the fundamental signal main component, and the fundamental signal main component is subjected to zero-crossing detection to obtain fundamental phase data; based on the fundamental phase data, the inverter fundamental amplitude within the inverter fundamental cycle is calculated, and based on the inverter fundamental amplitude, the fundamental signal main component is subjected to amplitude correction and phase correction to obtain fundamental main component data.

[0024] In practical applications, the original voltage and current signals are first collected by high-precision voltage transformers and current transformers deployed at the output end of the inverter. The sampling frequency is set to 50kHz to ensure the integrity of the signal. The collected data is digitally converted by 16-bit ADC and then transmitted to the controller. Then, the power frequency cycle is calculated for the collected sampling data. By statistically analyzing the time intervals between adjacent sampling points and combining the zero-point detection method, the complete waveform in the power frequency cycle is identified, thereby obtaining the distribution characteristics of multiple frequency bands including fundamental waves and harmonics. These frequency band distribution characteristics are then input into the corresponding bandwidth calculation unit, and the Butterworth filter design method is used to calculate the corresponding filter parameters such as center frequency, passband ripple and cutoff frequency for each frequency band. Then, based on the calculated filter parameters of each frequency band, the original voltage and current sampling data is processed by frequency band division, and the separation of signals of different frequency bands is achieved through a cascaded bandpass filter group, focusing on extracting the signal component of the fundamental frequency band, and performing signal-to-noise ratio evaluation on the extracted fundamental frequency band signal, that is, by calculating the ratio of signal energy to noise energy, the signal-to-noise ratio characteristic data reflecting the signal quality is obtained. Then, based on the calculated filter parameters of each frequency band, the original voltage and current sampling data is processed by frequency band division, and the separation of signals of different frequency bands is achieved through a cascaded bandpass filter group, focusing on extracting the signal component of the fundamental frequency band, and performing signal-to-noise ratio evaluation on the extracted fundamental frequency band signal, that is, by calculating the ratio of signal energy to noise energy, the signal-to-noise ratio characteristic data reflecting the signal quality is obtained. The adaptive threshold is set according to the signal-to-noise ratio characteristic data, and the wavelet transform method is used to perform multi-scale decomposition and noise reduction on the fundamental frequency band signal. The signal is reconstructed after eliminating high-frequency noise through the soft threshold method to obtain the voltage and current sampling data after preliminary filtering. Then, the improved zero-crossing detection algorithm is used to accurately calculate the inverter fundamental period by identifying the time interval between two consecutive rising edge zero-crossing points of the signal. Then, based on the inverter fundamental period, the sliding window method is used to calculate the mean of the voltage and current sampling data after preliminary filtering. The window length is set to one fundamental period. By moving the window point by point and The average value of the data in the window is calculated to obtain a relatively smooth fundamental signal principal component. At the same time, an accurate zero-crossing detection algorithm is applied to the principal component signal. The detection accuracy is improved by finding the intersection of the signal and the zero level and using a linear interpolation method to obtain fundamental phase data. Based on the fundamental phase data, the signal amplitude within the inverter fundamental period is calculated using the least squares fitting method, and the amplitude information is compared with the fundamental signal principal component obtained previously. Through amplitude comparison and phase difference calculation, accurate correction of the fundamental signal principal component is achieved, thereby obtaining accurate fundamental principal component data.

[0025] 102. Perform phase compensation and first coordinate transformation on fundamental wave main component data to obtain three-phase current and voltage data of αβ coordinate system, and perform positive and negative sequence decoupling operation on the three-phase current and voltage data of αβ coordinate system to obtain fundamental wave synchronous phase angle and grid fundamental wave frequency; In this embodiment, the first transformation here refers to Clarke transformation; the difference between two adjacent points in the fundamental main component data is calculated to obtain a sampling interval feature, and based on the sampling interval feature, the delay amount of the fundamental main component data is calculated to obtain an inverter sampling delay amount; the inverter sampling delay amount and the inverter fundamental wave period are proportionally calculated to obtain a phase compensation value, and based on the phase compensation value, the fundamental main component data is phase-adjusted to obtain pre-compensation data; the phase difference of the three-phase signal in the pre-compensation data is calculated to obtain a phase deviation value between the three phases, and based on the phase deviation value, the pre-compensation data is phase-calibrated to obtain three-phase voltage and current data with delay eliminated; the delay elimination The three-phase voltage and current data are subjected to Clarke transformation to obtain the three-phase current and voltage data of the αβ coordinate system; the three-phase current and voltage data of the αβ coordinate system are phase delayed by a preset delay angle to obtain orthogonal current and voltage data, and based on the orthogonal current and voltage data, signal addition and subtraction calculations are performed on the three-phase current and voltage data of the αβ coordinate system to obtain initial positive and negative sequence components; instantaneous amplitude calculations are performed on the initial positive and negative sequence components to obtain positive and negative sequence amplitude data, and phase detection is performed on the positive sequence components in the initial positive and negative sequence components to obtain instantaneous phase change; forward integration calculations are performed on the positive and negative sequence amplitude data to obtain the fundamental synchronous phase angle, and mean calculations are performed on the instantaneous phase change to obtain the fundamental frequency of the power grid.

[0026] In practical applications, the difference between adjacent sampling points in the fundamental principal component data is first calculated. Specifically, the amplitude difference and time difference between two adjacent points are calculated, and standardized in combination with the sampling frequency to obtain the sampling interval characteristics that reflect the characteristics of the actual sampling process. Then, based on these sampling interval characteristics, the time distribution of the sampling points is statistically analyzed using the weighted average method. The actual inverter sampling delay is calculated in combination with the sampling frequency and data processing delay of the system. The calculated inverter sampling delay is then ratio-calculated with the known inverter fundamental wave period, and the corresponding phase delay angle is obtained by angle conversion. The accurate phase is obtained by converting the delay angle into the corresponding compensation angle. The compensation value is then used to construct a phase correction matrix. The phase angle of the fundamental main component data is accurately adjusted through matrix operation to obtain preliminary pre-compensation data. In order to further improve the balance of the three-phase signal, the phase difference between the three-phase signals in the pre-compensation data is calculated respectively, and the actual phase difference angle between the adjacent two-phase signals is accurately extracted by using the vector analysis method. By comparing with the ideal 120-degree phase difference, the phase deviation value reflecting the degree of three-phase imbalance is obtained. Then, a compensation matrix is ​​constructed based on these deviation values, and the phase compensation algorithm based on the least squares method is used to accurately calibrate the pre-compensation data. The calculation formula of the phase difference estimation algorithm is: ; in is the phase difference that minimizes the error, and For any two-phase signal, is the angular frequency of the signal, and It is the fundamental component of the signal to accurately calculate the phase deviation between the three phases. For example, if the ideal phase difference should be 120°, but the actual measured value is 118.5°, a correction of 1.5° can be calculated, so that the three-phase voltage and current data with the phase delay effectively eliminated can be finally obtained through iterative calculation; then the Clarke transformation matrix is ​​applied to the three-phase voltage and current data with the delay effect eliminated, and the voltage and current data under the three-phase stationary coordinate system abc are converted to the two-phase orthogonal stationary coordinate system αβ through the 3 / 2 transformation. The specific transformation matrix used is: ; in is the voltage vector of the two-phase stationary coordinate system, K is the compensation coefficient matrix, is the three-phase voltage vector, It is the amount of unbalanced compensation, which is related to the deviation caused by three-phase imbalance and is used to compensate for the transformation error caused by three-phase imbalance. For example, when the three-phase voltage imbalance is 2%, by setting a suitable compensation coefficient, the voltage vector in the αβ coordinate system can be made more symmetrical, while keeping the power unchanged during the transformation process, and finally obtaining the three-phase current and voltage data in the αβ coordinate system. The accurate processing of the fundamental wave principal component data is achieved through the organic combination of sampling feature analysis, delay compensation, three-phase balance calibration and coordinate transformation.

[0027] Secondly, a phase delay of a preset delay angle (i.e., 90 degrees) is introduced into the data of the αβ coordinate system. Specifically, by designing appropriate damping coefficients and center frequency parameters, the improved second-order generalized integrator (SOGI) structure has good bandpass characteristics at the fundamental frequency, thereby obtaining current and voltage data orthogonal to the original signal. Then, based on the obtained orthogonal signals, the principle of the symmetrical component method is adopted to perform positive and negative sequence decomposition on the three-phase current and voltage data of the αβ coordinate system. Specifically, by performing addition and subtraction operations on the original signal and its orthogonal delayed signal, that is, the positive sequence component is composed of the original signal plus the orthogonal signal delayed by 90 degrees, and the negative sequence component is composed of the original signal minus the orthogonal signal delayed by 90 degrees, thereby obtaining the preliminary separated positive and negative sequence components; then, the instantaneous amplitudes of the separated positive and negative sequence components are calculated respectively, and the improved envelope detection algorithm is adopted to calculate the positive and negative sequence components in the αβ coordinate system. The vector modulus value under the condition of sigma-delta is obtained to obtain the positive and negative sequence amplitude data reflecting the signal strength. Meanwhile, an improved phase-locked loop (PLL) structure is used for phase tracking specifically for the positive sequence component. By calculating the phase increment between adjacent sampling points, the instantaneous phase change characterizing the dynamic characteristics of the system is obtained. Then, a forward integration algorithm is applied to the acquired positive and negative sequence amplitude data. By integrating the cumulative change of the positive sequence amplitude over time, and combining with an adaptive correction mechanism to eliminate the integral drift, an accurate fundamental synchronous phase angle is obtained. Meanwhile, a sliding average filtering is used for the instantaneous phase change obtained previously. By performing a weighted average calculation on the phase change in multiple consecutive cycles, the influence of phase noise is effectively filtered out. Finally, a stable fundamental frequency value of the power grid is obtained. This not only realizes the accurate decoupling of the positive and negative sequence components, but also maintains a good dynamic tracking performance when the power grid voltage is distorted or unbalanced.

[0028] 103. Based on the fundamental synchronous phase angle, perform a second coordinate transformation on the three-phase current and voltage data of the αβ coordinate system to obtain dq axis voltage and current data, and based on the fundamental frequency of the power grid, perform a delayed difference operation of the sliding average and harmonic power on the dq axis voltage and current data to obtain the inverter fundamental component and the inverter harmonic component; In this embodiment, the second coordinate transformation here refers to Park transformation; by calculating the sliding window length corresponding to the fundamental frequency of the power grid, and based on the sliding window length, performing moving summation calculation on the dq axis voltage and current data to obtain a sliding cumulative value; based on the sliding window length, performing mean calculation on the sliding cumulative value to obtain an initial fundamental component, and using the dq axis voltage and current data to perform a difference on the fundamental average component to obtain an initial harmonic component; performing sub-harmonic amplitude calculation on the initial harmonic component to obtain each harmonic data, and performing root mean square calculation on the initial fundamental component and the each harmonic data to obtain an inverter fundamental component and an inverter harmonic component; performing mean value calculation on the inverter fundamental component The dq axis voltage and the dq axis current in the inverter harmonic component are multiplied to obtain the fundamental active power and the fundamental reactive power, and the dq axis voltage and the dq axis current in the inverter harmonic component are multiplied to obtain the harmonic active power and the harmonic reactive power, and the fundamental apparent power between the fundamental active power and the fundamental reactive power is calculated; the rated apparent power capacity corresponding to the target inverter is compared with the fundamental apparent power to obtain the inverter residual capacity, and the compensation distribution calculation of the harmonic active power and the harmonic reactive power is performed based on the inverter residual capacity to obtain the compensated power characteristic quantity, and the fundamental active power and the fundamental reactive power are limited to the power extreme value to obtain the fundamental power characteristic quantity.

[0029] In practical applications, firstly, based on the fundamental frequency of the power grid, the optimal sliding window length is determined by calculating the number of sampling points corresponding to a complete power frequency cycle, that is, the sampling frequency is divided by the fundamental frequency of the power grid and rounded up. Then, the window length is used as the basic unit of data processing, and the dq axis voltage and current data are subjected to moving summation operation using an accumulator structure. By adding new sampling point data each time and removing the earliest sampling point data at the same time, the data in the sliding window is dynamically updated, thereby obtaining a sliding cumulative value reflecting the change in signal strength. Then, based on the determined sliding window length, the obtained sliding cumulative value is standardized, that is, the cumulative value is divided by the window length to obtain the average value of the data in the window. This improved moving average filter is used. The algorithm can effectively suppress the influence of high-frequency noise and obtain a relatively smooth initial fundamental component; then the original dq axis voltage and current data are subtracted from the extracted fundamental average component, and the initial harmonic component containing each harmonic is obtained through this difference method; then the initial harmonic component is subjected to spectrum analysis using an improved FFT algorithm, and the characteristic frequency components are identified in the dq coordinate system, mainly including the 6th and 12th characteristic harmonics, and the amplitude and phase information of each harmonic are calculated to obtain detailed harmonic data, and then the root mean square value of the extracted initial fundamental component and each harmonic data is calculated respectively, and the standardized inverter fundamental component and inverter harmonic component are obtained by performing square sum operation and square root operation on the sampled data within a complete cycle.

[0030] Secondly, based on the instantaneous power theory in the dq coordinate system, the product of the d-axis voltage and the d-axis current is taken as the fundamental active power component, and the product of the q-axis voltage and the q-axis current is taken as the fundamental reactive power component. The fundamental active power and fundamental reactive power of the system are obtained by real-time calculation of these product values. At the same time, the same calculation principle is also used for the extracted inverter harmonic components. The harmonic active power and harmonic reactive power in the system are calculated by processing the voltage and current product of the harmonic components in the dq coordinate system. Then, based on the obtained fundamental active power and fundamental reactive power, the vector sum between them is calculated by the vector synthesis method, that is, the active power and reactive power are squared respectively, added and then the square root is taken to obtain the fundamental apparent power that represents the overall power level of the system; the fundamental apparent power is then compared with the rated apparent power of the target inverter. The power capacity is compared and analyzed, and the current remaining capacity of the inverter is calculated by the capacity difference. Then, based on this remaining capacity value, the improved power allocation algorithm is used to optimize the allocation of harmonic active power and harmonic reactive power in the system, that is, according to the importance of each harmonic and the actual needs of the system, a reasonable allocation weight is set, and the compensation amount of each harmonic power is obtained through iterative calculation, thereby forming a compensation power characteristic amount containing a specific compensation strategy. At the same time, for the fundamental power part, based on the safe operation requirements of the system, a reasonable power limit range (such as 90% of the rated inverter power of the inverter) is set, and the fundamental active power and fundamental reactive power are processed by saturation limiting. Through real-time comparison and dynamic adjustment, it is ensured that the fundamental power is always kept within the safe range, and finally the fundamental power characteristic amount after limiting processing is obtained. Not only the accurate calculation of the fundamental power and harmonic power of the system is realized, but also through a reasonable capacity allocation strategy, it is ensured that the inverter can make full use of the remaining capacity for harmonic compensation while maintaining the fundamental power output, thereby improving the overall operation efficiency of the inverter.

[0031] 104. Based on the rated apparent power capacity corresponding to the target inverter, multi-level power calculation and power capacity allocation are performed on the inverter fundamental component and the inverter harmonic component to obtain the fundamental power characteristic quantity and the compensation power characteristic quantity, and error characteristic evaluation and decoupling operation are performed on the fundamental power characteristic quantity and the compensation power characteristic quantity to obtain the inverter power control quantity; In this embodiment, the error of the actual inverter output power is calculated for the fundamental power characteristic quantity and the compensation power characteristic quantity to obtain the inverter power deviation quantity, and the power control gain is calculated for the inverter power deviation quantity based on the inverter fundamental component and the inverter harmonic component to obtain the initial power control quantity; the initial power control quantity is converted into a dq-axis control value based on the inverter fundamental component and the inverter harmonic component to obtain a dq-axis decomposition quantity, and the corresponding fundamental data and harmonic data in the dq-axis decomposition quantity are superimposed to obtain a composite power control quantity; power comparison and power limitation are performed on the composite power control quantity and the rated apparent power capacity corresponding to the target inverter to obtain a limiting control quantity, and the limiting control quantity is used to perform a superposition operation on the original power control quantity corresponding to the target inverter to obtain the inverter power control quantity.

[0032] In practical applications, the error calculation of the fundamental power characteristic quantity and the compensation power characteristic quantity is performed, that is, the actual output power of the inverter is collected in real time, and the difference operation is performed with the two characteristic quantities. The error integration method is used to calculate the inverter power deviation reflecting the dynamic characteristics of the system, and the corresponding power control gain coefficients are designed based on the inverter fundamental component and the inverter harmonic component. The fundamental part adopts an adaptive PI control structure by dynamically adjusting the proportional coefficient and the integral time constant, while the harmonic part adopts a quasi-proportional resonant controller by adjusting the resonant frequency and bandwidth parameters. Finally, these gain coefficients are multiplied with the power deviation to obtain the initial power control quantity containing the fundamental and harmonic information; then, based on the inverter fundamental component and the inverter harmonic component, the initial power control quantity is subjected to coordinate transformation processing, that is, the improved Park transformation algorithm is used to convert the control quantity into a synchronously rotating dq coordinate system to obtain the fundamental and harmonic information. The corresponding d-axis and q-axis components are then weighted and superimposed on the fundamental data and harmonic data in these dq-axis decomposition quantities. By setting reasonable weight coefficients and comprehensively considering the needs of fundamental power control and harmonic compensation, a synthetic power control quantity reflecting the overall control strategy of the system is obtained; the synthetic power control quantity is then compared with the rated apparent power capacity of the target inverter in real time, and the control quantity exceeding the capacity range is saturated by setting a dynamic limiting threshold to obtain a safe and reliable limiting control quantity. Then, according to the actual operating state of the inverter, this limiting control quantity is superimposed on the original power control quantity of the inverter, and the control parameters are updated in a smooth transition manner. Finally, the inverter power control quantity that ensures the stable operation of the system is obtained, and precise control of the inverter output power is achieved. In particular, the hierarchical control structure is adopted to ensure the stable output of the fundamental power and the effective compensation of the harmonic components.

[0033] 105. Based on the fundamental wave synchronization phase angle, the inverter power control amount is modulated by output signal to generate an output power control result of the target inverter.

[0034] In this embodiment, based on the fundamental synchronous phase angle, a space vector PWM modulation strategy is adopted. By calculating the intersection of the three-phase modulation wave and the carrier, basic duty cycle information is obtained. At the same time, combined with the size of the inverter power control amount, the modulation ratio is calculated and dynamically adjusted in real time to obtain a preliminary basic inverter modulation signal. Then, for the harmonic components that may exist in the modulation signal, a selective harmonic elimination algorithm is used to optimize the harmonic content of the basic inverter modulation signal by presetting a specific switching angle sequence, that is, the weight of each harmonic is determined by Fourier series expansion, and the optimal switching angle is solved by the Newton iteration method to obtain an optimized basic inverter modulation signal with smaller harmonic distortion; then the optimized modulation signal is subjected to a dead zone effect analysis, and a mathematical model between the dead zone time and the output voltage distortion is established to calculate the The voltage loss caused by the dead zone effect is to consider the switching characteristics of the power device and the delay characteristics of the driving circuit, adopt an adaptive dead zone compensation algorithm, calculate the accurate inverter dead zone compensation amount according to the current direction and dead zone time, and then perform waveform correction on the optimized basic inverter modulation signal based on the compensation amount. By inserting compensation pulses or adjusting the pulse width in the original PWM waveform, accurate compensation for the dead zone effect is achieved, and a compensation modulation signal with higher waveform quality is obtained; then the carrier synchronization processing is performed on the compensation modulation signal, and the precise synchronization of the PWM carrier and the system clock is achieved through the digital phase-locked loop technology, and the improved oversampling technology is used to improve the PWM resolution. At the same time, combined with the optimal pulse width modulation strategy, the harmonic characteristics of the output waveform are further optimized, and finally the inverter power control amount that meets the system requirements is obtained. Not only the precise control of the inverter output is achieved, but also the waveform quality of the output voltage is effectively improved, the harmonic distortion of the system is reduced, and the control performance of the inverter on the output power is enhanced.

[0035] In the embodiment of the present invention, the voltage and current data at the output end of the target inverter are sampled and multi-band filtered to obtain the fundamental main component characteristics, and then phase compensation and coordinate transformation are performed to obtain three-phase data in the αβ coordinate system and realize positive and negative sequence decoupling, and obtain the fundamental synchronous phase angle and grid frequency; then the data is converted to the dq coordinate system based on the synchronous phase angle, and the fundamental and harmonic components are separated by sliding average and delay difference calculation; then the power calculation and capacity allocation are performed on these components, and the power control amount is obtained by combining error evaluation and decoupling operation; finally, the signal modulation output control result is performed based on the synchronous phase angle. Through hierarchical signal processing and control calculation, the problem of accurate control of the inverter output power is solved, especially in terms of harmonic separation and power distribution, the dynamic characteristics of the inverter are fully considered, the control accuracy is effectively improved, and a multi-level decoupling and error compensation strategy is adopted, which not only ensures the output power quality, but also enhances the stability of the inverter output power, thereby realizing efficient and accurate control of the inverter output power as a whole.

[0036] The output power control method of the inverter in the embodiment of the present invention is described above. The output power control device of the inverter in the embodiment of the present invention is described below. Figure 2 , an embodiment of the output power control device of the inverter in the embodiment of the present invention includes: The fundamental wave extraction module 201 is used to obtain the voltage and current sampling data of the output end of the target inverter, and perform power frequency fundamental wave extraction and multi-band bandpass filtering on the voltage and current sampling data to obtain fundamental wave main component data; The first transformation module 202 is used to perform phase compensation and first coordinate transformation on the fundamental wave main component data to obtain three-phase current and voltage data of the αβ coordinate system, and perform positive and negative sequence decoupling operation on the three-phase current and voltage data of the αβ coordinate system to obtain the fundamental wave synchronization phase angle and the fundamental wave frequency of the power grid; A second transformation module 203 is used to perform a second coordinate transformation on the three-phase current and voltage data of the αβ coordinate system based on the fundamental synchronous phase angle to obtain dq axis voltage and current data, and perform a delayed difference operation of sliding average and harmonic power on the dq axis voltage and current data based on the fundamental frequency of the power grid to obtain an inverter fundamental component and an inverter harmonic component; The power adjustment module 204 is used to perform multi-level power calculation and power capacity allocation on the inverter fundamental component and the inverter harmonic component based on the rated apparent power capacity corresponding to the target inverter, obtain a fundamental power characteristic amount and a compensation power characteristic amount, and perform error characteristic evaluation and decoupling operation on the fundamental power characteristic amount and the compensation power characteristic amount to obtain an inverter power control amount; The signal modulation module 205 is used to perform output signal modulation on the inverter power control amount based on the fundamental wave synchronization phase angle to generate an output power control result of the target inverter.

[0037] In the embodiment of the present invention, the voltage and current data at the output end of the target inverter are sampled and multi-band filtered to obtain the fundamental main component characteristics, and then phase compensation and coordinate transformation are performed to obtain three-phase data in the αβ coordinate system and realize positive and negative sequence decoupling, and obtain the fundamental synchronous phase angle and grid frequency; then the data is converted to the dq coordinate system based on the synchronous phase angle, and the fundamental and harmonic components are separated by sliding average and delay difference calculation; then the power calculation and capacity allocation are performed on these components, and the power control amount is obtained by combining error evaluation and decoupling operation; finally, the signal modulation output control result is performed based on the synchronous phase angle. Through hierarchical signal processing and control calculation, the problem of accurate control of the inverter output power is solved, especially in terms of harmonic separation and power distribution, the dynamic characteristics of the inverter are fully considered, the control accuracy is effectively improved, and a multi-level decoupling and error compensation strategy is adopted, which not only ensures the output power quality, but also enhances the stability of the inverter output power, thereby realizing efficient and accurate control of the inverter output power as a whole.

[0038] above Figure 2 The output power control device of the inverter in the embodiment of the present invention is described in detail from the perspective of modular functional entities. The output power control device of the inverter in the embodiment of the present invention is described in detail from the perspective of hardware processing.

[0039] Figure 3 : is a schematic diagram of the structure of an output power control device of an inverter provided by an embodiment of the present invention. The output power control device 300 of the inverter may have relatively large differences due to different configurations or performances, and may include one or more processors (central processing units, CPU) 310 (for example, one or more processors) and a memory 320, and one or more storage media 330 (for example, one or more mass storage devices) storing application programs 333 or data 332. Among them, the memory 320 and the storage medium 330 can be short-term storage or permanent storage. The program stored in the storage medium 330 may include one or more modules (not shown in the figure), and each module may include a series of instruction operations in the output power control device 300 of the inverter. Furthermore, the processor 310 may be configured to communicate with the storage medium 330 to execute a series of instruction operations in the storage medium 330 on the output power control device 300 of the inverter.

[0040] The output power control device 300 of the inverter may further include one or more power supplies 340, one or more wired or wireless network interfaces 350, one or more input and output interfaces 360, and / or one or more operating systems 331, such as Windows Serve, Mac OS X, Unix, Linux, FreeBSD, etc. It will be appreciated by those skilled in the art that Figure 3 The structure of the output power control device of the inverter shown does not constitute a limitation on the output power control device of the inverter, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0041] The present invention also provides an output power control device for an inverter, wherein the computer device includes a memory and a processor, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the processor executes each step of the output power control method for the inverter in the above-mentioned embodiments.

[0042] The present invention also provides a computer-readable storage medium, which may be a non-volatile computer-readable storage medium or a volatile computer-readable storage medium. Instructions are stored in the computer-readable storage medium. When the instructions are executed on a computer, the computer executes each step of the output power control method of the inverter.

[0043] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0044] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the whole or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program code.

[0045] The present application can be used in many general or special computer system environments or configurations. For example: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, etc. The present application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present application can also be practiced in distributed computing environments, in which tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in local and remote computer storage media including storage devices.

[0046] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling output power of an inverter, characterized in that: The output power control method of the inverter comprises: Acquire voltage and current sampling data of the output end of the target inverter, and perform power frequency fundamental wave extraction and multi-band bandpass filtering on the voltage and current sampling data to obtain fundamental wave main component data; Performing phase compensation and a first coordinate transformation on the fundamental wave main component data to obtain three-phase current and voltage data of an αβ coordinate system, and performing positive and negative sequence decoupling operations on the three-phase current and voltage data of the αβ coordinate system to obtain a fundamental wave synchronous phase angle and a fundamental wave frequency of a power grid; Based on the fundamental synchronous phase angle, a second coordinate transformation is performed on the three-phase current and voltage data of the αβ coordinate system to obtain dq axis voltage and current data, and based on the fundamental frequency of the power grid, a sliding average and a delayed difference operation of the harmonic power are performed on the dq axis voltage and current data to obtain an inverter fundamental component and an inverter harmonic component; Based on the rated apparent power capacity corresponding to the target inverter, multi-level power calculation and power capacity allocation are performed on the inverter fundamental component and the inverter harmonic component to obtain a fundamental power characteristic amount and a compensation power characteristic amount, and error characteristic evaluation and decoupling operation are performed on the fundamental power characteristic amount and the compensation power characteristic amount to obtain an inverter power control amount; Based on the fundamental wave synchronization phase angle, the inverter power control amount is modulated by an output signal to generate an output power control result of the target inverter.

2. The output power control method of the inverter according to claim 1, characterized in that: The step of extracting the power frequency fundamental wave and performing multi-band bandpass filtering on the voltage and current sampling data to obtain fundamental wave main component data includes: Performing power frequency cycle calculation on the voltage and current sampling data to obtain frequency band distribution characteristics, and performing filter bandwidth calculation on the frequency band distribution characteristics to obtain filter parameters for each frequency band; Based on the frequency band filter parameters, the voltage and current sampling data are subjected to frequency band filtering to obtain a fundamental frequency band signal, and a signal-to-noise ratio evaluation is performed on the fundamental frequency band signal to obtain signal-to-noise ratio characteristic data; Based on the signal-to-noise ratio characteristic data, the fundamental frequency band signal is subjected to noise reduction and signal reconstruction to obtain the voltage and current sampling data after preliminary filtering, and the power frequency cycle detection is performed on the voltage and current sampling data after preliminary filtering to obtain the inverter fundamental wave cycle; Based on the inverter fundamental wave period, the fundamental wave mean value of the voltage and current sampling data after the preliminary filtering is calculated to obtain the main component of the fundamental wave signal, and the zero-crossing point detection is performed on the main component of the fundamental wave signal to obtain the fundamental wave phase data; Based on the fundamental wave phase data, the inversion fundamental wave amplitude within the inversion fundamental wave period is calculated, and based on the inversion fundamental wave amplitude, the amplitude correction and phase correction are performed on the fundamental wave signal main component to obtain fundamental wave main component data.

3. The output power control method of the inverter according to claim 2, characterized in that: The performing phase compensation and first coordinate transformation on the fundamental wave principal component data to obtain three-phase current and voltage data in an αβ coordinate system includes: Performing difference calculation on two adjacent points in the fundamental wave principal component data to obtain a sampling interval characteristic, and performing delay calculation on the fundamental wave principal component data based on the sampling interval characteristic to obtain an inversion sampling delay; Performing a proportional operation on the inverter sampling delay and the inverter fundamental wave period to obtain a phase compensation value, and based on the phase compensation value, performing a phase adjustment on the fundamental wave main component data to obtain pre-compensation data; Performing phase difference calculation on the three-phase signals in the pre-compensation data to obtain phase deviation values ​​between the three phases, and performing phase calibration on the pre-compensation data based on the phase deviation values ​​to obtain three-phase voltage and current data with delay eliminated; Clarke transformation is performed on the three-phase voltage and current data with time delay eliminated to obtain the three-phase current and voltage data in the αβ coordinate system.

4. The output power control method of the inverter according to claim 1, characterized in that: The positive and negative sequence decoupling operation is performed on the three-phase current and voltage data of the αβ coordinate system to obtain the fundamental synchronous phase angle and the fundamental frequency of the power grid, including: Performing a phase delay of a preset delay angle on the three-phase current and voltage data of the αβ coordinate system to obtain orthogonal current and voltage data, and performing signal addition and subtraction calculation on the three-phase current and voltage data of the αβ coordinate system based on the orthogonal current and voltage data to obtain initial positive and negative sequence components; Performing instantaneous amplitude calculation on the initial positive and negative sequence components to obtain positive and negative sequence amplitude data, and performing phase detection on the positive sequence component in the initial positive and negative sequence components to obtain an instantaneous phase change; The positive and negative sequence amplitude data are forwardly integrated to obtain a fundamental synchronous phase angle, and the instantaneous phase variation is averaged to obtain a grid fundamental frequency.

5. The output power control method of the inverter according to claim 1, characterized in that: The method of performing a sliding average and a delayed difference operation of harmonic power on the dq axis voltage and current data based on the fundamental frequency of the power grid to obtain an inverter fundamental component and an inverter harmonic component includes: Calculating the sliding window length corresponding to the fundamental frequency of the power grid, and performing a moving summation calculation on the dq axis voltage and current data based on the sliding window length to obtain a sliding cumulative value; Based on the sliding window length, the sliding cumulative value is averaged to obtain an initial fundamental component, and the fundamental average component is subtracted by using the dq axis voltage and current data to obtain an initial harmonic component; The initial harmonic component is subjected to sub-harmonic amplitude calculation to obtain each harmonic data, and the initial fundamental component and each harmonic data are subjected to root mean square value calculation to obtain an inversion fundamental component and an inversion harmonic component.

6. The output power control method of the inverter according to claim 1, characterized in that: The method of performing multi-level power calculation and power capacity allocation on the inverter fundamental wave component and the inverter harmonic component based on the rated apparent power capacity corresponding to the target inverter to obtain a fundamental wave power characteristic amount and a compensation power characteristic amount includes: The dq axis voltage and the dq axis current in the inverter fundamental wave component are multiplied to obtain the fundamental wave active power and the fundamental wave reactive power, and the dq axis voltage and the dq axis current in the inverter harmonic component are multiplied to obtain the harmonic active power and the harmonic reactive power, and the fundamental wave apparent power between the fundamental wave active power and the fundamental wave reactive power is calculated; The rated apparent power capacity corresponding to the target inverter is compared with the fundamental apparent power to obtain the remaining capacity of the inverter, and the compensation allocation calculation of the harmonic active power and the harmonic reactive power is performed based on the remaining capacity of the inverter to obtain the compensation power characteristic quantity, and the power extreme value limit is performed on the fundamental active power and the fundamental reactive power to obtain the fundamental power characteristic quantity.

7. The output power control method of the inverter according to claim 6, characterized in that: The step of performing error characteristic evaluation and decoupling operation on the fundamental power characteristic quantity and the compensation power characteristic quantity to obtain the inverter power control quantity includes: Performing an error calculation of the actual inverter output power on the fundamental power characteristic quantity and the compensation power characteristic quantity to obtain an inverter power deviation quantity, and performing power control gain calculation on the inverter power deviation quantity based on the inverter fundamental component and the inverter harmonic component to obtain an initial power control quantity; Based on the inverter fundamental wave component and the inverter harmonic component, the initial power control amount is converted into a dq axis control value to obtain a dq axis decomposition amount, and the corresponding fundamental wave data and harmonic wave data in the dq axis decomposition amount are respectively superimposed to obtain a synthetic power control amount; The composite power control amount is compared and limited in power with the rated apparent power capacity corresponding to the target inverter to obtain a limit control amount, and the limit control amount is used to perform a superposition operation on the original power control amount corresponding to the target inverter to obtain an inverter power control amount.

8. An output power control device for an inverter, characterized in that: The output power control device of the inverter comprises: A fundamental wave extraction module is used to obtain voltage and current sampling data at the output end of the target inverter, and perform power frequency fundamental wave extraction and multi-band bandpass filtering on the voltage and current sampling data to obtain fundamental wave main component data; A first transformation module is used to perform phase compensation and a first coordinate transformation on the fundamental wave main component data to obtain three-phase current and voltage data of an αβ coordinate system, and perform positive and negative sequence decoupling operations on the three-phase current and voltage data of the αβ coordinate system to obtain a fundamental wave synchronous phase angle and a grid fundamental wave frequency; A second transformation module is used to perform a second coordinate transformation on the three-phase current and voltage data of the αβ coordinate system based on the fundamental synchronous phase angle to obtain dq axis voltage and current data, and perform a delayed difference operation of sliding average and harmonic power on the dq axis voltage and current data based on the fundamental frequency of the power grid to obtain an inverter fundamental component and an inverter harmonic component; A power adjustment module, configured to perform multi-level power calculation and power capacity allocation on the inverter fundamental component and the inverter harmonic component based on the rated apparent power capacity corresponding to the target inverter, obtain a fundamental power characteristic amount and a compensation power characteristic amount, and perform error characteristic evaluation and decoupling operation on the fundamental power characteristic amount and the compensation power characteristic amount to obtain an inverter power control amount; The signal modulation module is used to perform output signal modulation on the inverter power control amount based on the fundamental wave synchronization phase angle to generate an output power control result of the target inverter.

9. An output power control device for an inverter, characterized in that: The output power control device of the inverter comprises: a memory and at least one processor, wherein instructions are stored in the memory; The at least one processor calls the instruction in the memory to enable the output power control device of the inverter to perform each step of the output power control method of the inverter according to any one of claims 1 to 7.

10. A computer-readable storage medium having instructions stored thereon, characterized in that: When the instructions are executed by the processor, the various steps of the output power control method of the inverter as described in any one of claims 1 to 7 are implemented.

Images