Voltage harmonic compensation control method and system

Abstract

The present invention relates to a voltage harmonic compensation control method and system, belonging to the field of harmonic control technology. First, voltage detection is performed to obtain a voltage detection result. Voltage harmonic control is performed based on the voltage detection result to generate a voltage harmonic instruction. A current harmonic instruction is obtained based on the voltage harmonic instruction and a virtual impedance coefficient. The current harmonic instruction is rate-controlled to slow down the increase rate of the current harmonic instruction and limit the increase rate of the current voltage harmonic instruction value. Harmonic current control is performed based on the current harmonic instruction after rate control. This method slows down the harmonic instruction speed, reduces the impact of harmonic voltage changes on the harmonic instruction, and enhances the harmonic compensation effect.

Description

Technical Field

[0001] The present invention relates to a voltage harmonic compensation control method and system, belonging to the technical field of harmonic control. Background Art

[0002] In the current power grid operation, in order to reduce the active power loss, the star SVG (compensation device of voltage source converter) is often connected in parallel in the power grid. The main circuit topology of the star SVG is as follows: Figure 1 As shown, the power module cascade mode is as follows Figure 2 As shown, dynamic adjustment of reactive power is achieved, power factor is improved, system voltage is stabilized, and harmonics at the control point are reduced.

[0003] The star-shaped SVG currently used in the new energy sector uses current harmonics as the control target for control. SVG controls the current harmonics at the control point to zero by emitting harmonics with the same amplitude and opposite phase as the harmonic load current, thereby making the current harmonics flowing from the control point to the main grid zero. However, when the star-shaped SVG used in the power distribution sector uses current harmonics as the control target, the direction of current harmonics changes at any time depending on the grid structure, load conditions, and power flow conditions. Therefore, voltage harmonics are used as the control target for power quality management. When voltage harmonics are used as the control target, the control block diagram is as follows: Figure 3 As shown, it includes a voltage harmonic detection link, a voltage harmonic control link and a current harmonic control link. The voltage harmonic detection link refers to the calculation of the virtual impedance coefficient through the control algorithm in the voltage harmonic control link after the detection of a specific order harmonic voltage, and then the specific order harmonic current detection process. The current control instruction is finally obtained through the control algorithm of the current harmonic control link. The basic control function is realized according to the current control instruction. There are the following problems in the generation of control instructions and the control process. First, both voltage harmonics and current harmonics need to be detected, and harmonics of each frequency require independent current harmonic control, which leads to a large amount of calculation for the control algorithm; secondly, the real-time change rate of voltage harmonics is relatively large, which makes it difficult to adjust the parameters of the harmonic voltage compensation link, and the compensation effect is poor. The accuracy of the harmonic detection algorithm will be affected by the harmonics of the power grid, resulting in false detection. Summary of the Invention

[0004] The object of the present invention is to provide a voltage harmonic compensation control method and system to solve the problem of poor compensation effect caused by large real-time change rate of voltage harmonics.

[0005] To achieve the above object, the solution of the present invention includes:

[0006] A voltage harmonic compensation control method of the present invention comprises the following steps:

[0007] 1) Perform voltage detection to obtain voltage detection results, perform voltage harmonic control based on the voltage detection results, and generate voltage harmonic instructions;

[0008] 2) Based on the voltage harmonic command and the virtual impedance coefficient, the current harmonic command is obtained, and the rate of the current harmonic command is controlled to slow down the increase rate of the current harmonic command and limit the increase rate of the current current harmonic command value;

[0009] 3) Perform harmonic current control based on the current harmonic instruction after rate control.

[0010] Beneficial effect: The voltage harmonic compensation control method of the present invention, based on the existing voltage harmonic detection link, voltage harmonic control link and current harmonic control link, converts the voltage harmonic instruction into a current harmonic instruction at the output of the voltage harmonic control link, and then adds a current harmonic instruction rate control link. By adding this link, the slope control is increased, the speed of the current harmonic instruction is slowed down, the current harmonic instruction changes little in real time, and then the change of the grid harmonic current is slowed down, and the impact of large harmonic changes on the harmonic instruction is reduced, so that the virtual impedance coefficient is increased and the SVG output harmonics under the same harmonic voltage content are increased, thereby achieving the purpose of enhancing the harmonic compensation effect.

[0011] Furthermore, the rate control method of the current harmonic instruction is: the instruction modulus is calculated according to the current harmonic instruction, the modulus increment coefficient is determined according to the instruction modulus and the set modulus upper limit, the increasing speed of the current harmonic instruction is limited, and the current harmonic instruction is used to control the harmonic current.

[0012] Beneficial effect: The vector rate control algorithm used in the voltage harmonic command rate link ensures that the output current and the harmonic voltage command always maintain a purely resistive relationship, avoiding the risk of resonance.

[0013] The modulus increment coefficient is:

[0014]

[0015] Where, v mod_out_0 is the module value output at the previous moment, △v is the compensation module value, v mod_out_limit The set module value limit is determined according to the initial input module value and the set module value maximum value.

[0016] Beneficial effects: The modulus increment coefficient can be calculated based on the modulus value output at the previous moment. Different coefficients will result in different current components output in different axes. At the same time, instruction rate control solves the problem of matching the SVG output current change speed with the real-time performance of the harmonic voltage detection algorithm. This improves the harmonic compensation effect without increasing the real-time performance requirements of the harmonic voltage detection algorithm.

[0017] Furthermore, the harmonic detection algorithm used in the voltage harmonic detection process is as follows: after multiple transformations of the n-1th negative-sequence harmonic voltage and the n+1th positive-sequence harmonic voltage in the rotating coordinate system, the harmonics are converted into DC components. After the DC components are processed by a low-pass filter, the filtered harmonic information is gain amplified, and the processed voltage harmonic information is subjected to voltage harmonic control, where n>2.

[0018] Beneficial effect: The improved harmonic detection algorithm can improve the accuracy of harmonic detection.

[0019] Furthermore, the current harmonic instruction after rate control includes the current harmonic instruction of the n+1th rotating coordinate system and the current harmonic instruction of the n-1th rotating coordinate system. When performing harmonic current control, the current harmonic instruction of the rotating coordinate system is converted into the power frequency rotating coordinate system.

[0020] Furthermore, the low-pass filter includes a second-order ButterWorth low-pass filter and a mean filter arranged in series, wherein the mean filter is used to adopt a sliding window averaging algorithm that matches the harmonic frequency, and the transfer function of the second-order ButterWorth low-pass filter is:

[0021]

[0022] Where H(s) is the transfer function, ω n is the cutoff frequency, ξ is the damping ratio, and s is a complex parameter.

[0023] Beneficial effects: The mean filter algorithm and the second-order ButterWorth low-pass filter algorithm are simple and easy to implement, and have a significant suppression effect on the situation where noise points are dense.

[0024] Furthermore, during the voltage harmonic detection process, the phase angle used in the coordinate transformation is a virtual phase angle, which is obtained by calculating the output frequency of the phase-locked loop after low-pass filtering the output frequency.

[0025] Beneficial effects: The present invention optimizes the phase angle used in the harmonic detection algorithm and uses a virtual phase angle for harmonic detection, thereby ensuring the accuracy of voltage harmonic detection.

[0026] Furthermore, a quasi-vector resonant controller is used for control during the current harmonic control process.

[0027] Beneficial effect: The controller only controls signals of a specific frequency, thereby achieving control of harmonic current without using a harmonic current detection link.

[0028] A voltage harmonic compensation control system of the present invention includes a processor, wherein the processor is used to execute instructions to implement the voltage harmonic compensation control method described above.

[0029] Beneficial effects: The voltage harmonic compensation control system of the present invention has a simple structure and includes a processor. By increasing the slope control, the speed of the harmonic instruction is slowed down, thereby slowing down the change of the harmonic voltage of the power grid and reducing the impact of the harmonic voltage change on the harmonic instruction. Therefore, after increasing the virtual impedance coefficient, the SVG output harmonics under the same harmonic voltage content are increased, thereby achieving the purpose of improving the harmonic compensation effect. The vector rate control algorithm used in the voltage harmonic instruction rate link ensures that the output current and the harmonic voltage instruction always maintain a purely resistive relationship, avoiding the risk of resonance. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the SVG main circuit topology in the prior art;

[0031] Figure 2 This is a schematic diagram of the star-shaped SVG power module cascade in the prior art;

[0032] Figure 3 It is a schematic diagram of a conventional voltage harmonic control algorithm in the prior art;

[0033] Figure 4 2 is a schematic diagram of a voltage harmonic control algorithm in an embodiment of the method of the present invention;

[0034] Figure 5 2 is a schematic diagram of a harmonic voltage detection algorithm in an embodiment of the method of the present invention;

[0035] Figure 6 2 is a schematic diagram of a harmonic detection virtual phase angle generation algorithm in an embodiment of the method of the present invention;

[0036] Figure 7 This is a block diagram of the harmonic instruction rate control link in the method embodiment of the present invention;

[0037] Figure 8 1 is a Bode diagram of 6-times VR, 12-times VR, 18-times VR and 24-times VR controllers connected in parallel in the method embodiment of the present invention;

[0038] FIG9( a ) is a schematic diagram of the overall waveform of an embodiment of the method of the present invention;

[0039] FIG9( b ) is a waveform diagram of an embodiment of the method of the present invention before the function is put into use;

[0040] FIG9( c ) is a waveform diagram of the method embodiment of the present invention after the function is put into use. DETAILED DESCRIPTION

[0041] The present invention will be further described in detail below with reference to the accompanying drawings.

[0042] The concept of the present invention is to address the problems in the prior art and provide a voltage harmonic compensation control method and system based on a star-type SVG. The control method is based on the voltage harmonic detection link, voltage harmonic control link, and current harmonic control link in the existing control method, and adds a current harmonic instruction rate control link, that is, the current harmonic instruction is rate-controlled, the speed of the current harmonic instruction is controlled to slow down, and the current harmonic instruction after rate control is used to perform harmonic current control.

[0043] Voltage harmonic compensation control method embodiment:

[0044] like Figure 4 The voltage harmonic compensation control method shown in the figure first includes a voltage harmonic detection step and a voltage harmonic control step. Specifically, voltage detection is performed to obtain a voltage detection result, and voltage harmonic control is performed based on the voltage detection result to generate a voltage harmonic command. It also includes a current harmonic command rate control step, which controls the rate of increase of the current harmonic command to slow down the increase rate of the current harmonic command and limit the increase rate of the current harmonic command value. Finally, harmonic current control is performed based on the current harmonic command after rate control to achieve the purpose of improving the harmonic compensation effect.

[0045] After generating the voltage harmonic command, the corresponding current harmonic command is derived based on the voltage harmonic command and the virtual impedance coefficient. Specifically, the conversion from the voltage harmonic command to the current harmonic command is accomplished by the voltage harmonic control link. The current harmonic command is equal to the product of the voltage harmonic command and the virtual impedance coefficient. The current harmonic command rate control method is as follows: the command modulus is calculated based on the current harmonic command. The modulus increment coefficient is determined based on the command modulus and the set modulus upper limit. The increase rate of the current harmonic command is limited, and the current harmonic command is used to control the harmonic current. Specifically, the d-axis and q-axis command rates of the harmonic current are calculated in real time, and the modulus is calculated based on the d-axis and q-axis commands. It is judged whether the command modulus output at the previous moment is greater than or equal to the set modulus limit. If it is greater than or equal to, the current modulus increment coefficient is set to 1, and the currently output d-axis and q-axis harmonic currents are equal to the currently input d-axis and q-axis harmonic currents. Otherwise, the modulus increment coefficient is calculated based on the modulus obtained at the previous moment and the set modulus limit. The currently output d-axis and q-axis harmonic currents are calculated using the modulus increment coefficient. The current command modulus is obtained using the current d-axis and q-axis harmonic currents. The d-axis and q-axis harmonic currents are continued to be judged against the set modulus limit. The d-axis and q-axis harmonic currents finally output are used to control the power grid to achieve voltage harmonic compensation for the power grid.

[0046] The process of current harmonic command rate control is as follows: Figure 7As shown, the current harmonic command is gradually changed from the current value to id_set_in and iq_set_in, and during the change process, the direction of the vector v_out formed by the output of the rate control link id_set_out and iq_set_out is maintained consistent with the direction of the vector v_in formed by the input id_set_in and iq_set_in. First, calculate the dq axis command modulus v mod_set , and the instruction modulus v mod The formula is:

[0047]

[0048] Where, v d is the command rate of the d-axis, v q is the instruction rate of the q-axis.

[0049] According to the instruction modulo value v mod_set And set the upper limit of the modulus v mod_set_max Calculate the output value limit modulus v mod_out_limit (Set the module limit), the value is:

[0050] v mod_out_limit =min(v mod_set v mod_set_max )

[0051] Calculate the modulus of the actual id and iq at the current moment, that is, the modulus v of the output of the rate control link at the previous moment mod_out_0 , calculate the modulus value v of the output instruction based on the output value of the previous moment mod_out_0 , determine whether the modulus value at the previous moment is greater than or equal to the output value limit modulus value v mod_out_limit , and calculate the corresponding modulus increment coefficient k based on the judgment result, where the modulus increment coefficient k is:

[0052]

[0053] In the formula, △v is the compensation modulus. By setting the size of △v, the speed of the voltage harmonic instruction can be controlled, thereby realizing the current harmonic instruction rate control. Among them, in each control cycle, the modulus v mod_out_0 Accumulate ΔV. When the module value is accumulated to v mod_out_0 When the values ​​are equal, the harmonic current command changes to id_set_in and iq_set_in. When the modulus increment coefficient k increases to 1, the current command value increases to the set command value. Because the dq axis command growth coefficients are consistent during the current command value increase, the angle of the vector synthesized by the dq axis commands remains unchanged, ensuring that the program remains purely resistive after passing through the current harmonic command rate control link.

[0054] The vector rate control algorithm used in the current harmonic command rate control method ensures that the output current and harmonic voltage commands always maintain a purely resistive relationship, avoiding the risk of resonance. At the same time, command rate control solves the problem of matching the SVG output current change speed with the real-time performance of the harmonic voltage detection algorithm, improving the harmonic compensation effect without increasing the real-time performance requirements of the harmonic voltage detection algorithm.

[0055] The current harmonic instructions after rate control include the current harmonic instructions of the n+1th rotating coordinate system and the current harmonic instructions of the n-1th rotating coordinate system. When performing harmonic current control, the current harmonic instructions of the rotating coordinate system are converted into the power frequency rotating coordinate system. In order to obtain higher harmonic detection accuracy, the detection algorithm used in the voltage harmonic detection link in this embodiment is the optimized detection algorithm. The optimized detection algorithm is as follows: Figure 5 As shown, Figure 5 Where h is the harmonic number, LPF is the low-pass filter for harmonic detection, K h is the harmonic detection gain, which is used to compensate for the amplitude attenuation caused by the low-pass filter. The low-pass filter for harmonic detection includes a second-order ButterWorth low-pass filter and a mean filter connected in series. The transfer function of the second-order ButterWorth low-pass filter is:

[0056]

[0057] Where H(s) is the transfer function, ω n is the cutoff frequency, ξ is the damping ratio, and s is a complex parameter. n =2·pi·f, f is a parameter lower than 50HZ, which can be 35Hz, and the damping ratio ξ is generally taken as 0.707.

[0058] The mean filter uses a sliding window averaging algorithm that matches the harmonic frequency, with a data window length of 20ms, which can filter out all components that are integer multiples of the power frequency.

[0059] The phase angle θ used in the coordinate transformation in the figure s The virtual phase angle used is obtained by using the SVG phase-locked loop to phase-lock the power grid. The phase angle and frequency output by the phase-locked loop will be affected by the background harmonics of the power grid. Directly using the phase angle output by the phase-locked loop for harmonic detection will lead to false detection of harmonics. Therefore, the phase angle used in the harmonic detection algorithm in this embodiment is a virtual phase angle. Figure 6 As shown, after the output frequency of the phase-locked loop is low-pass filtered, the virtual phase angle is calculated and used to perform harmonic detection, thereby ensuring the accuracy of voltage harmonic detection.

[0060] The principle of the detection method in the voltage harmonic command rate link is as follows: the grid voltage is transformed into the hth-order rotating coordinate system, and the hth-order harmonic will become a DC component. After filtering out other components through a low-pass filter, the hth-order harmonic information can be obtained. Thereafter, the harmonic information is gain-amplified and can be used for subsequent control.

[0061] This embodiment also utilizes a virtual impedance coefficient for voltage harmonic control and harmonic command conversion. Setting the virtual impedance to a pure real number ensures that the SVG output current has a purely resistive characteristic, reducing the risk of system resonance. The selection of virtual resistance R requires comprehensive consideration of the system impedance and the SVG's own capabilities. It can initially be set to the system impedance or 1 / 2 of the system impedance and can be adjusted later based on the compensation effect. Virtual impedance coefficient = 1 / virtual resistance R. Theoretically, the smaller the virtual resistance, that is, the larger the virtual impedance coefficient, the better the harmonic compensation effect. However, if the virtual impedance coefficient is too large, the SVG will become more sensitive to grid voltage harmonics. That is, even if the grid voltage harmonics change slightly, the harmonics output by the SVG will still change dramatically, which will adversely affect both SVG control and the grid itself. Therefore, in actual engineering applications, the virtual impedance coefficient is obtained as follows: Initially, virtual resistance R is set to the system impedance or 1 / 2 of the system impedance. This initial virtual impedance coefficient is used to calculate the initial virtual impedance coefficient, which can control the harmonic voltage to 50% or 33% of the original harmonic voltage. Thereafter, the virtual impedance coefficient is gradually increased based on the actual project situation until the following conditions are met and the impedance coefficient is no longer increased:

[0062] When the impedance coefficient is increased, the voltage harmonic compensation effect is not significantly improved. At this time, the virtual impedance is already small compared to the system impedance. Increasing the impedance coefficient cannot effectively improve the compensation capability. Instead, it will have an adverse effect on the system due to its sensitivity to voltage harmonic fluctuations. In this embodiment, the controller used in the current harmonic control process is a quasi-vector resonant controller, that is, a VR controller, and its transfer function is as follows:

[0063]

[0064] Where G VR (s) is the transfer function, 2ω n s(k prh s+k irh ) is the zero point of the transfer function, s 2 +2ω ch s+(hω1) 2 The bode diagram of multiple VR controllers connected in parallel is shown as Figure 8As shown. This controller controls only signals of a specific frequency, thereby enabling harmonic current control without using a harmonic current detection link. Furthermore, to convert the harmonic current instructions of the n+1 and n-1 rotating coordinate systems into the power frequency rotating coordinate system for control, this embodiment also includes a current harmonic instruction coordinate transformation step.

[0065] Since the n-1 negative-sequence harmonics and the n+1 positive-sequence harmonics exhibit n-order harmonic characteristics when transformed into the positive-sequence power frequency rotating coordinate system, an n-order VR controller is used to construct a current harmonic controller. This controller can simultaneously control the n-1 negative-sequence harmonics and the n+1 positive and negative-sequence harmonics. Compared to other harmonic control methods, this reduces the number of current harmonic controllers required. Here, n refers to the resonant frequency parameter of the VR controller in the current harmonic control link, where n>2. In a balanced three-phase system, due to symmetry, even-order harmonics are eliminated, leaving only odd-order harmonics. Therefore, loads that cause harmonics exhibit odd-order harmonics (n±1). For example, a three-phase rectifier load will produce harmonic currents of 6k±1 orders, such as the 5th, 7th, 11th, 13th, 17th, and 19th orders. The inverter primarily generates the 5th and 7th harmonics.

[0066] After the above operation process, the operation results are shown in Figures 9(a), 9(b), and 9(c). These are the hardware-in-the-loop simulation test results of the star-type SVG using this harmonic voltage control algorithm. The top waveform in Figure 9(a) shows the voltage waveform at the control point, the middle waveform in Figure 9(a) shows the current waveform, and the bottom waveform in Figure 9(a) shows the current waveform output by the SVG. Figure 9(b) shows the waveform before the voltage harmonic compensation function is enabled (blue for phase A, brown for phase B, and green for phase C). Figure 9(c) shows the waveform before the voltage harmonic compensation function is enabled, with yellow for phase A, green for phase B, and red for phase C.

[0067] Fifth harmonic voltage control begins at 4 seconds. As can be seen, after the SVG executes the harmonic voltage control algorithm, it simulates its resistance characteristics to generate fifth harmonic currents. This current is then shunted based on the relationship between the system impedance and the SVG's virtual impedance, reducing the fifth harmonic current flowing into the main grid and the fifth harmonic in the grid voltage. System stability is excellent, with no oscillations. This demonstrates that after this function is activated, the SVG actively outputs current harmonics, reducing the harmonic voltage at the control point and improving the voltage at that point.

[0068] Voltage harmonic compensation control system embodiment:

[0069] In this embodiment, a voltage harmonic compensation control system includes a memory, a processor, and an internal bus. The processor and memory communicate and exchange data with each other via the internal bus. The memory includes at least one memory capable of storing data. The processor executes software programs and modules stored in the memory to perform various functional applications and process data, thereby implementing a voltage harmonic compensation control method described in a method embodiment of the present invention.

[0070] That is, the method in the above method embodiment should be understood as a process of a voltage harmonic compensation control method that can be implemented by computer program instructions. These computer program instructions can be provided to a processor so that the processor executes these instructions to generate the functions specified in the above method process.

[0071] The processor may be a microprocessor MCU, a programmable logic device FPGA or other processing devices.

[0072] The memory can be various types of memories that use electrical energy to store information, such as RAM, ROM, etc.; it can also be various types of memories that use magnetic energy to store information, such as hard disks, floppy disks, magnetic tapes, magnetic core memories, bubble memories, USB flash drives, etc.; it can also be various types of memories that use optical methods to store information, such as CDs, DVDs, etc.; of course, it can also be other types of memories, such as quantum memories, graphene memories, etc.

[0073] While specific embodiments have been described above, the present invention is not limited to the described embodiments. The fundamental concept of the present invention lies in the aforementioned basic scheme. Based on the teachings of the present invention, those skilled in the art can devise various variations of models, formulas, and parameters without inventive effort. Changes, modifications, substitutions, and variations to the embodiments without departing from the principles and spirit of the present invention remain within the scope of protection of the present invention.

Claims

1. A voltage harmonic compensation control method, characterized in that: The method comprises the following steps: 1) Perform voltage detection to obtain voltage detection results, perform voltage harmonic control based on the voltage detection results, and generate voltage harmonic instructions; 2) Based on the voltage harmonic command and the virtual impedance coefficient, the current harmonic command is obtained, and the rate of the current harmonic command is controlled to slow down the increase rate of the current harmonic command and limit the increase rate of the current current harmonic command value; 3) Perform harmonic current control based on the current harmonic instruction after rate control; The rate control method of the current harmonic instruction is as follows: the instruction modulus is calculated according to the current harmonic instruction, the modulus increment coefficient is determined according to the instruction modulus and the set modulus upper limit, the increase speed of the current harmonic instruction is limited, and the current harmonic instruction is used to control the harmonic current; The modulus increment coefficient is: Where, v mod_out_0 is the module value output at the previous moment, △v is the compensation module value, v mod_out_limit The set module value limit is determined according to the initial input module value and the set module value maximum value.

2. The voltage harmonic compensation control method according to claim 1, characterized in that: The harmonic detection algorithm used in the voltage harmonic detection process is as follows: after multiple transformations of the n-1th negative-sequence harmonic voltage and the n+1th positive-sequence harmonic voltage in the rotating coordinate system, the harmonics are converted into DC components. After the DC components are processed by a low-pass filter, the filtered harmonic information is gain amplified, and the processed voltage harmonic information is subjected to voltage harmonic control, where n>2.

3. The voltage harmonic compensation control method according to claim 2, characterized in that: The current harmonic instructions after rate control include the current harmonic instructions of the n+1th rotating coordinate system and the current harmonic instructions of the n-1th rotating coordinate system. When performing harmonic current control, the current harmonic instructions of the rotating coordinate system are converted into the industrial frequency rotating coordinate system.

4. The voltage harmonic compensation control method according to claim 2, characterized in that: The low-pass filter includes a second-order ButterWorth low-pass filter and a mean filter arranged in series. The mean filter is used to adopt a sliding window averaging algorithm that matches the harmonic frequency. The transfer function of the second-order ButterWorth low-pass filter is: Where H(s) is the transfer function, ω n is the cutoff frequency, ξ is the damping ratio, and s is a complex parameter.

5. The voltage harmonic compensation control method according to claim 2, characterized in that: During the voltage harmonic detection process, the phase angle used in the coordinate transformation is a virtual phase angle, which is obtained by calculating the output frequency of the phase-locked loop after low-pass filtering the output frequency.

6. The voltage harmonic compensation control method according to claim 1, characterized in that: A quasi-vector resonant controller is used in the current harmonic control process.

7. A voltage harmonic compensation control system, comprising a processor, characterized in that: The processor is configured to execute instructions to implement the voltage harmonic compensation control method according to any one of claims 1 to 6.

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