Rectifier control method, system, device and computer readable storage medium

Abstract

The present application discloses a rectifier control method, system, device and computer-readable storage medium, which are applied to the field of rectifier control. The rectifier control method includes: obtaining the phase voltage of each phase on the grid side of the rectifier in the current power frequency cycle, determining the reference phase voltage among all phase voltages, and determining the phase voltages other than the reference phase voltage as the phase voltage to be adjusted; correcting each phase voltage to be adjusted so that the amplitude of the phase voltage of each phase after correction is balanced, and calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage; obtaining the compensation phase voltage corresponding to each phase voltage to be adjusted; and performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages. The present application can suppress the harmonic current caused by the imbalance of the grid-side voltage amplitude.

Description

Technical Field

[0001] The present application relates to the field of rectifier control, and in particular to a rectifier control method, system, device and computer-readable storage medium. Background Art

[0002] PWM (Pulse width modulation) rectifier has the advantages of small grid-side harmonic current, stable DC voltage, high power factor, bidirectional flow of electric energy, high power density, high efficiency and energy saving, etc. It is widely used in many fields such as new energy power generation, charging piles, switching power supplies, inverters and white appliances. Among them, the three-phase three-wire voltage-type PWM rectifier is the classic topology of PWM rectification. The commonly used modulation methods are SPWM (Sinusoidal Pulse Width Modulation) and SVPWM (Space Vector Pulse Width Modulation). Compared with SPWM, SVPWM can obtain higher voltage utilization, faster dynamic response and modulate a more perfect sinusoidal voltage.

[0003] Considering that the traditional SVPWM modulation method based on sector search is relatively complex to calculate and has a large amount of code for operation, the current method is to inject zero-sequence voltage components (third voltage harmonics) into the calculated three-phase reference phase voltage based on the conventional SPWM control method to achieve the SVPWM effect. However, in the application site of high-power equipment, the unsatisfactory grid voltage conditions and interference from other electrical equipment will cause the grid-side voltage amplitude to be unbalanced. Due to the imbalance of the grid-side voltage amplitude, the conduction time of the three-phase switch tube calculated by the harmonic injection SVPWM algorithm is inaccurate, resulting in a large third harmonic current on the grid-side current.

[0004] Therefore, how to provide a solution to the above technical problems is a problem that those skilled in the art need to solve at present. Summary of the invention

[0005] The purpose of the present application is to provide a rectifier control method, system, device and computer-readable storage medium, which can suppress the harmonic current caused by the unbalanced voltage amplitude on the grid side.

[0006] In order to solve the above technical problems, the present application provides a rectifier control method, comprising:

[0007] Obtaining the phase voltage of each phase on the grid side of the rectifier in the current power frequency cycle, determining a reference phase voltage among all the phase voltages, and determining the phase voltages except the reference phase voltage as the phase voltage to be adjusted;

[0008] Correcting each of the phase voltages to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced, and calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage;

[0009] Obtaining a compensation phase voltage corresponding to each phase voltage to be adjusted;

[0010] The rectifier is modulated by SVPWM according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages.

[0011] Optionally, the process of determining a reference phase voltage among all the phase voltages includes:

[0012] A phase voltage having the smallest peak voltage among all the phase voltages is determined as a reference phase voltage.

[0013] Optionally, the process of correcting each of the phase voltages to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced includes:

[0014] Acquire a correction parameter of a current power frequency cycle, wherein the correction parameter is determined based on the phase voltage of each phase in a previous power frequency cycle;

[0015] Each of the phase voltages to be adjusted is corrected using the correction parameters so that the amplitudes of the phase voltages of the phases after correction are balanced.

[0016] Optionally, after determining a reference phase voltage among all the phase voltages and determining the phase voltages other than the reference phase voltage as the phase voltage to be adjusted, the rectifier control method further includes:

[0017] The correction parameter of the phase to be adjusted corresponding to each phase voltage to be adjusted in the next power frequency cycle is calculated by the first relational expression, wherein the first relational expression is:

[0018] Among them, E i is the peak voltage of the i-th phase voltage to be adjusted, k i is the correction parameter of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted in the next power frequency cycle, E r is the peak voltage of the reference phase voltage.

[0019] Optionally, the process of obtaining the compensation phase voltage corresponding to each phase voltage to be adjusted includes:

[0020] The compensation phase voltage corresponding to each phase voltage to be adjusted is calculated by the second relational expression, wherein the second relational expression is u icom =p(1-1 / K i )E pi ;

[0021] Among them, p is the compensation coefficient, K i is the correction parameter of the i-th phase voltage to be adjusted, E pi is the i-th phase voltage to be adjusted, u icom is the compensation phase voltage corresponding to the i-th phase voltage to be adjusted.

[0022] Optionally, after respectively calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage, the rectifier control method further includes:

[0023] determining a maximum reference phase voltage and a minimum reference phase voltage among all the reference phase voltages;

[0024] The zero-sequence voltage is calculated by a third relational expression, which is:

[0025] in, is the zero-sequence voltage, is the maximum reference phase voltage, is the minimum reference phase voltage.

[0026] Optionally, the process of performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages includes:

[0027] Obtaining the turn-on time of the switch tube of each phase of the rectifier through the fourth relationship, and controlling the corresponding switch tube of each phase based on the turn-on time;

[0028] The fourth relation is

[0029] in, u icom are the reference phase voltage and compensation phase voltage corresponding to the i-th phase voltage to be adjusted, T icomp is the turn-on time of the switch tube of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted, is the reference phase voltage corresponding to the reference phase voltage, T rcomp is the turn-on time of the switch tube of the reference phase corresponding to the reference phase voltage, is the zero sequence voltage, T s is the carrier period, U dc is the output voltage.

[0030] In order to solve the above technical problems, the present application also provides a rectifier control system, including:

[0031] A first acquisition module is used to acquire the phase voltage of each phase on the grid side of the rectifier in the current power frequency cycle, determine the reference phase voltage among all the phase voltages, and determine the phase voltages except the reference phase voltage as the phase voltage to be adjusted;

[0032] A correction module, used for correcting each of the phase voltages to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced, and respectively calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage;

[0033] A second acquisition module, used for acquiring a compensation phase voltage corresponding to each phase voltage to be adjusted;

[0034] The modulation module is used to perform SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages.

[0035] In order to solve the above technical problems, the present application also provides a rectifier control device, comprising:

[0036] Memory for storing computer programs;

[0037] A processor is used to implement the steps of the rectifier control method as described in any one of the above when executing the computer program.

[0038] To solve the above technical problems, the present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the rectifier control method as described in any one of the above are implemented.

[0039] The present application provides a rectifier control method, firstly determining the reference phase voltage and the phase voltage to be adjusted in the phase voltage of each phase of the current power frequency cycle of the rectifier, correcting each phase voltage to be adjusted so that the amplitude of the phase voltage of each phase after correction is balanced, then calculating the reference phase voltage of each phase based on the phase voltage of each phase after correction, and calculating the compensation phase voltage of each phase voltage to be adjusted, the present application superimposes the compensation phase voltage on the reference phase voltage of the corresponding phase and combines it with the zero-sequence voltage for SVPWM modulation, so that the calculated conduction time of the three-phase switch tube is more accurate, thereby suppressing the harmonic current caused by the unbalanced voltage amplitude on the grid side. The present application also provides a rectifier control system, device and computer-readable storage medium, which have the same beneficial effects as the above-mentioned rectifier control method. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 A flow chart of the steps of a rectifier control method provided in this application;

[0042] Figure 2 A schematic diagram of a reference voltage synthesis provided in this application;

[0043] Figure 3a A schematic diagram of the spatial voltage vector action time of an SVPWM algorithm provided in this application;

[0044] Figure 3b A schematic diagram of three-phase switching timing generated by carrier comparison provided in this application;

[0045] Figure 4 A schematic diagram of a SVPWM rectifier topology structure provided in this application;

[0046] Figure 5 A SVPWM rectifier control block diagram provided in this application;

[0047] Figure 6a to Figure 6e A schematic diagram of simulation analysis of a SVPWM with harmonic current suppression algorithm injection type provided in this application;

[0048] Figure 7a to Figure 7e A schematic diagram of simulation analysis of a SVPWM without harmonic current suppression algorithm injection provided in this application;

[0049] Figure 8a to Figure 8e This is a schematic diagram of traditional SVPWM simulation analysis;

[0050] Fig. 9 This is a schematic diagram of the structure of a rectifier control system provided in this application. DETAILED DESCRIPTION

[0051] The core of this application is to provide a rectifier control method, system, device and computer-readable storage medium, which can suppress the harmonic current caused by the unbalanced voltage amplitude on the grid side.

[0052] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0053] Please refer to Figure 1 , Figure 1 A flow chart of the steps of a rectifier control method provided in the present application, the rectifier control method comprising:

[0054] S101: Obtain the phase voltage of each phase on the grid side of the rectifier in the current power frequency cycle, determine the reference phase voltage among all phase voltages, and determine the phase voltage other than the reference phase voltage as the phase voltage to be adjusted;

[0055] Considering that the grid voltage conditions are not ideal in actual application sites, the interference of other electrical equipment may cause the grid-side voltage amplitude to be unbalanced. If the rectifier is controlled according to the three-phase voltage with unbalanced amplitude, it will cause the rectifier DC side voltage to fluctuate by double frequency, which will lead to three-phase imbalance and large distortion of the grid-side current. Therefore, in this embodiment, the three-phase voltage on the grid side of the rectifier is obtained according to the preset power frequency cycle, that is, the phase voltage E of phase a pa , b-phase voltage E pb and the phase voltage E of phase c pc , so that the rectifier can be controlled according to the amplitude of the three-phase voltage.

[0056] After obtaining the phase voltages of each phase on the rectifier grid side, this embodiment may also include an operation of determining whether the amplitudes of the three phase voltages are balanced. Amplitude balance here may refer to the absolute value of the difference between the amplitudes of any two phase voltages being within a preset error range, so that the amplitudes of the three phase voltages tend to be consistent. As a preferred solution, the difference between the amplitudes of any two phase voltages being 0 may also be determined as amplitude balance. If the amplitudes of the three phase voltages are unbalanced, a reference phase voltage is determined among the three phase voltages, and the phase voltages of the remaining phases except the reference phase voltage are determined as the phase voltages to be adjusted. An example is given for the selection of the reference phase voltage and the phase voltage to be adjusted. Assume that E pa ≠E pb ≠E pc , E pa Determined as the reference phase voltage, then E pb and E pc That is, the phase voltage to be adjusted, or E pb Determined as the reference phase voltage, then E pa and E pcThat is, the phase voltage to be adjusted. You can also use E pc Determined as the reference phase voltage, then E pa and E pb That is the phase voltage to be adjusted; assuming E pa =E pb ≠E pc , E pa and E pb Determine as the reference phase voltage, and set E pc Determine the phase voltage to be adjusted, or set E pc Determine as the reference phase voltage, and set E pa and E pb Determine the phase voltage to be adjusted.

[0057] As a preferred embodiment, after obtaining the phase voltage of each phase on the grid side, it also includes the operation of performing zero-bias correction on the phase voltage of each phase, and determining the reference phase voltage and the phase voltage to be adjusted in the phase voltage of each phase after zero-bias correction, thereby improving the accuracy of the data.

[0058] As an optional embodiment, the process of determining the reference phase voltage among all phase voltages includes: determining the phase voltage with the smallest peak voltage among all phase voltages as the reference phase voltage.

[0059] S102: Correcting each phase voltage to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced, and calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage;

[0060] Specifically, after determining the reference phase voltage and the adjustment phase voltage in the above steps, the reference phase voltage is used as a reference value to correct the phase voltage to be adjusted, so that the corrected phase voltage to be adjusted is consistent with the reference phase voltage. For example, assuming that E pa ≠E pb ≠E pc , in S101, change E pc Determined as the reference phase voltage, due to E pa and E pb Both with E pc If not, then E pa and E pb All are determined as the phase voltage to be adjusted. pa Correction to obtain e a , for E pb Correction to obtain e b , let E pc =e c , we can get e a =e b =e c , at this time e a 、e b and ec That is, a set of balanced three-phase voltage values. Based on the balanced amplitude of the three phase voltages on the grid side, a 、e b and e c Calculate the three-phase reference phase voltage for subsequent SVPWM. Specifically, when correcting each phase voltage to be adjusted, the phase voltage to be adjusted can be adjusted by the correction parameter corresponding to the phase voltage to be adjusted. The correction parameter can be a fixed value set in advance based on multiple tests or experience, or can be calculated in real time. This embodiment does not limit how to obtain the correction parameter.

[0061] S103: Obtaining a compensation phase voltage corresponding to each phase voltage to be adjusted;

[0062] Specifically, although the phase voltage to be adjusted is corrected in the previous step so that the corrected three-phase voltage reaches an amplitude balance, the actual grid-side voltage is still in an amplitude imbalance state. If the rectifier is still modulated by SVPWM based on the reference phase voltage of each phase obtained by the above calculation, it will still cause a large third harmonic current to appear in the grid-side current. Therefore, the compensation phase voltage corresponding to each phase voltage to be adjusted is also calculated in this step, so that the compensation phase voltage can be superimposed on the reference phase voltage of the corresponding phase later, thereby suppressing the interference of the unbalanced voltage on the grid side on the current and correcting the phase of the current to a certain extent.

[0063] S104: Perform SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages.

[0064] Specifically, after obtaining the reference phase voltage and compensation phase voltage of each phase through the above steps, the reference phase voltage, third-order zero-sequence voltage and compensation phase voltage of each phase are used as inputs of the harmonic injection SVPWM algorithm to calculate the switching time of the rectifier switch tube, thereby suppressing the interference of the unbalanced grid-side voltage amplitude on the sinusoidality and balance of the grid-side current.

[0065] It can be seen that in the rectifier control method provided in the present embodiment, the reference phase voltage and the phase voltage to be adjusted in the phase voltage of each phase in the current power frequency cycle of the rectifier are first determined, and each phase voltage to be adjusted is corrected to balance the amplitude of the phase voltage of each phase after correction, and then the reference phase voltage of each phase is calculated based on the corrected phase voltage of each phase, and the compensation phase voltage of each phase voltage to be adjusted is calculated. The present application superimposes the compensation phase voltage on the reference phase voltage of the corresponding phase and combines it with the zero-sequence voltage for SVPWM modulation, so that the calculated conduction time of the three-phase switch tube is more accurate, thereby suppressing the harmonic current caused by the imbalance of the grid-side voltage amplitude.

[0066] Based on the above embodiments:

[0067] As an optional embodiment, the process of correcting each phase voltage to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced includes:

[0068] Obtaining correction parameters of the current power frequency cycle, where the correction parameters are determined based on the phase voltages of each phase in the previous power frequency cycle;

[0069] Each phase voltage to be adjusted is corrected by using the correction parameters so that the amplitudes of the phase voltages of each phase after correction are balanced.

[0070] Specifically, considering that in actual applications, the amplitude of the grid-side voltage collected in adjacent power frequency cycles does not change much, for example, in the previous power frequency cycle, the phase voltage of phase C is smaller, and the phase voltages of phases A and B are larger, then in the current power frequency cycle, it is highly likely that the phase voltage of phase C is still smaller, and the phase voltages of phases A and B are larger. Therefore, in this embodiment, the correction parameters are determined based on the phase voltages of each phase in the previous power frequency cycle, thereby improving the effectiveness and accuracy of the correction.

[0071] It is understandable that after obtaining the phase voltages of the three phases in the previous power frequency cycle, the correction parameters required for the next power frequency cycle (ie, the current power frequency cycle) are calculated based on the phase voltages of the three phases so that the correction parameters can be used in the current power frequency cycle.

[0072] The number of correction parameters is determined according to the number of phase voltages to be adjusted. Each phase corresponding to the phase voltage to be adjusted will correspond to a correction parameter. Assuming that the phase voltage to be adjusted in the previous power frequency cycle is E pa and E pb , then the correction parameter k corresponding to a can be calculated a , b corresponds to the correction parameter k b , in the current power frequency cycle through k a The phase voltage E of phase a obtained in the current cycle pa Correction is performed by k pb The phase voltage E of phase b obtained in the current cycle pb Make corrections.

[0073] As an optional embodiment, after determining the reference phase voltage among all phase voltages and determining the phase voltages other than the reference phase voltage as the phase voltage to be adjusted, the rectifier control method further includes:

[0074] The correction parameter of the phase to be adjusted corresponding to each phase voltage to be adjusted in the next power frequency cycle is calculated by the first relational expression. The first relational expression is:

[0075] Among them, E i is the peak voltage of the i-th phase voltage to be adjusted, k iis the correction parameter of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted in the next power frequency cycle, E r is the peak voltage of the reference phase voltage.

[0076] Specifically, the phase corresponding to the phase voltage to be adjusted is the phase to be adjusted. For example, the phase voltage peak value of phase c collected in the current power frequency cycle is the smallest, that is, the phase voltage of phase c is the reference phase voltage, the phase voltage of phase a and the phase voltage of phase b are the first phase voltage to be adjusted and the second phase voltage to be adjusted respectively, then phase a is the first phase to be adjusted, phase b is the second phase to be adjusted, the peak voltage of the phase voltage of phase a is E1, the peak voltage of the phase voltage of phase b is E2, and the peak voltage of the phase voltage of phase c is E r , k1 and k2 are the ratio of the peak voltage of phase a to the peak voltage of phase c and the ratio of the peak voltage of phase b to the peak voltage of phase c, that is, It can be understood that k1 is the correction parameter of the phase voltage of phase a in the next power frequency cycle, and k2 is the correction parameter of the phase voltage of phase b in the next power frequency cycle. In the next power frequency cycle, when the phase voltage of the corresponding phase is corrected by the correction parameter, it can be obtained:

[0077]

[0078] It can be understood that in the current power frequency cycle, the phase voltage to be adjusted of the phase to be adjusted corresponding to the current power frequency cycle is corrected by the correction parameter calculated according to the above scheme in the previous power frequency cycle, so that the corrected phase voltage e a 、e b With the reference phase voltage e c As a set of balanced three-phase voltage values, the following is based on e a 、e b 、e c A scheme for obtaining the reference phase voltage is described below.

[0079] Specifically, refer to Figure 2 , the traditional SVPWM algorithm divides a complex plane into 6 sectors in one power frequency cycle. According to the volt-second balance principle, the position of the reference voltage vector is determined, and the adjacent basic voltage vectors (U1~U6) and zero vectors (U0, U7) are selected to modulate the required machine-side voltage. The following takes the reference voltage located in sector I as an example, U1 and U2 are effective voltage vectors, and T1 and T2 are their respective voltage vectors in the carrier cycle T s Internal action time.

[0080] refer to Figure 3a and Figure 3b , in the unified random PWM modulation algorithm, the action time of each phase can be expressed by the following formula:

[0081]

[0082] In formula (2), T a , T b , T c are the conduction time of the upper bridge arms of the three phases respectively. When k=0.5, the algorithm is the traditional SVPWM.

[0083] Combined with Figure 3, Figure 4 , in time T1, the DC voltage acts on points ab, and in time T2, the DC voltage acts on points bc. According to the volt-second balance principle, we can get:

[0084]

[0085] In formula (3), U ab , U bc It is the line voltage between ab and bc on the machine side within one carrier cycle.

[0086] PWM pulse width modulation is to obtain the gate signal of the switch tube by comparing the triangular carrier with the three-phase sine wave to be modulated. The triangular carrier can be expressed as follows:

[0087]

[0088] In formula (4), u t , U tp They represent the instantaneous value and maximum value of the three-phase modulation voltage respectively, and t represents the conduction time of the upper bridge arm of a certain phase. When SPWM modulation is adopted (i.e. the modulation wave is a sine wave), U tp =0.5U dc ( Figure 2 (a, b, c are the voltages relative to n').

[0089] Taking phase a as an example, we get:

[0090]

[0091] In the formula, u at * is the phase voltage during SPWM modulation.

[0092] Substituting equation (2) and equation (3) into equation (5), we get:

[0093]

[0094] In the formula, when k = 0.5, That is SVPWM. Since the algorithm is now transformed from SPWM modulation (modulation wave is a sine wave) to SVPWM modulation (modulation wave is a saddle wave), the grid-side phase voltage calculated earlier, such as u at * Amplify the amplitude to u a* , that is, multiply by the coefficient The modulation ratio changes from 1 / 2 of SPWM modulation to 1 / 2 of SVPWM modulation.

[0095] As an optional embodiment, after respectively calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage, the rectifier control method further includes:

[0096] determining a maximum reference phase voltage and a minimum reference phase voltage among all reference phase voltages;

[0097] The zero-sequence voltage is calculated by the third relation:

[0098] in, is the zero sequence voltage, is the maximum reference phase voltage, is the minimum reference phase voltage.

[0099] Specifically, in the first sector, the voltage of phase a is the largest and the voltage of phase c is the smallest, so equation (6) can also be written as:

[0100]

[0101] In the formula, u max * 、u min * is the maximum and minimum value of the modulated phase voltage. According to the derivation of the above formula, it can be summarized as:

[0102]

[0103] In the formula, is the SVPWM modulated sinusoidal three-phase reference phase voltage, u0 * It is the third harmonic voltage, that is, the zero-sequence voltage injected by the third harmonic.

[0104] As an optional embodiment, the process of obtaining the compensation phase voltage corresponding to each phase voltage to be adjusted includes:

[0105] The compensation phase voltage corresponding to each phase voltage to be adjusted is calculated by the second relational expression, wherein the second relational expression is u icom =p(1-1 / K i )E pi ;

[0106] Among them, p is the compensation coefficient, K i is the correction parameter of the i-th phase voltage to be adjusted, E pi is the i-th phase voltage to be adjusted, u icom is the compensation phase voltage corresponding to the i-th phase voltage to be adjusted.

[0107] Combined with the above embodiment of calculating the correction parameter by the first relational expression, the correction parameter K used in the current power frequency cycle is i That is, the correction parameter k calculated according to the first relation in the previous power frequency cycle i .

[0108] Specifically, the phase voltages of phases a and b are multiplied by (1-1 / K1) and (1-1 / K2) respectively, and then multiplied by the compensation coefficient p to obtain the compensated phase voltage u of phase a. acom , the compensation phase voltage u of phase b bcom ,Right now:

[0109]

[0110] In this embodiment, u acom and u bcom They are respectively superimposed on the reference phase voltage of the corresponding phase to be adjusted to suppress the interference of the unbalanced voltage on the grid side on the current, and can correct the phase of the current to a certain extent.

[0111] As an optional embodiment, the process of performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages includes:

[0112] Obtain the turn-on time of the switch tube of each phase of the rectifier through the fourth relational expression, and control the corresponding switch tube of each phase based on the turn-on time;

[0113] The fourth relation is

[0114] in, u icom are the reference phase voltage and compensation phase voltage corresponding to the i-th phase voltage to be adjusted, T icomp is the turn-on time of the switch tube of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted, is the reference phase voltage corresponding to the reference phase voltage, T rcomp is the turn-on time of the switch tube of the reference phase corresponding to the reference phase voltage, is the zero sequence voltage, T s is the carrier period, U dc is the output voltage.

[0115] Specifically, the turn-on time of the three-phase switch tube can be calculated according to the voltage components obtained above. Referring to the above, taking phase c as the reference phase and phase a and phase b as the phases to be adjusted as an example, the turn-on time of each phase switch tube can be calculated by the following formula:

[0116]

[0117] Where, Tacomp , T bcomp , T ccomp They are respectively the turn-on time of the a-phase switch tube, the turn-on time of the b-phase switch tube, and the turn-on time of the c-phase switch tube.

[0118] Refer to the following Figure 5 The SVPWM rectifier control block diagram shown in the figure further illustrates the above scheme. The phase voltage E of phase a, phase b, and phase c of the current power frequency cycle is collected. pa 、E pb 、E pc Assuming that the phase voltage peak value of phase c is the smallest, then the correction coefficients k1 and k2 calculated from the previous power frequency cycle are respectively pa and E pb Correction is performed to obtain the corrected phase voltage e a and e b , let E pc =e c , e a 、e b and e c Input phase-locked loop PLL, output e d 、e q and θ, and calculate the phase voltage E to be adjusted according to the compensation coefficient p and the correction coefficients k1 and k2 pa and E pb The compensation phase voltage u acom and u bcom , e d 、e q and θ are input into the dq / adc module for coordinate transformation to obtain u a 、u b 、u c , Figure 5 U abc Indicates u a 、u b 、u c , and then amplify its amplitude to obtain the reference phase voltage u of each phase a * 、u b * 、u c * , that is, multiply by the coefficient Figure 5 Medium Indicates u a * 、u b * 、u c * , according to u a * 、u b* 、u c * The maximum reference phase voltage and the minimum reference phase voltage in the zero-sequence voltage u0 are obtained * , refer to Figure 5 As shown, u acom and u bcom The switching time of the three-phase switch tubes is calculated as the input of the harmonic injection SVPWM algorithm.

[0119] For example, given the grid-side voltage a phase amplitude of 1.2×311V, b phase amplitude of 1.1×311V, c phase voltage amplitude of 311V, the phase difference of each phase is 120 degrees, the grid-side inductance is 1.2mH, the DC side capacitance is 4000uF, the load resistance is 10Ω, the DC side voltage is set to 650V, and the carrier frequency is 4kHz. When the grid voltage amplitude is unbalanced, while keeping the DC side voltage fluctuation within a certain range, the algorithm proposed in this patent is conducive to suppressing the injection of the grid-side third harmonic current, thereby reducing the Thd of the grid-side current. Compared with the injection SVPWM method without harmonic current suppression, the algorithm proposed in this application greatly reduces the harmonics of the grid-side current; it is more effective than the traditional SVPWM algorithm in suppressing the harmonics of the grid-side current, and has some improvements in the imbalance of the phase current amplitude and the power factor angle deviation.

[0120] Related data reference Figure 6a to Figure 6e , Figure 7a to Figure 7e , Figure 8a to Figure 8e And as shown in Table 1. Among them, Figure 6a to Figure 6e This is a schematic diagram of simulation analysis of a SVPWM with harmonic current suppression algorithm injection type provided in this application. Figure 6a The schematic diagram of the three-phase grid-side current obtained by simulating the SVPWM injection type with harmonic current suppression algorithm. Figure 6b The DC side voltage schematic diagram obtained by simulating the SVPWM injection type with harmonic current suppression algorithm. Figure 6c This is the FFT analysis diagram of the a-phase current obtained by simulating the SVPWM with harmonic current suppression algorithm injection. Figure 6d This is the FFT analysis diagram of the b-phase current obtained by simulating the SVPWM with harmonic current suppression algorithm injection. Figure 6e This is a schematic diagram of the FFT analysis of the c-phase current obtained by simulating the SVPWM injection type with harmonic current suppression algorithm. Figure 7a to Figure 7e This is a simulation analysis diagram of a SVPWM without harmonic current suppression algorithm injection provided in this application. Figure 7a The schematic diagram of the three-phase grid-side current obtained by simulating the SVPWM injection type without the harmonic current suppression algorithm. Figure 7b The DC side voltage schematic diagram obtained by simulating the SVPWM injection type without harmonic current suppression algorithm. Figure 7cThis is the FFT analysis diagram of the a-phase current obtained by simulating the SVPWM without the harmonic current suppression algorithm injection. Figure 7d This is the FFT analysis diagram of the b-phase current obtained by simulating the SVPWM without the harmonic current suppression algorithm injection. Figure 7e This is a schematic diagram of the FFT analysis of the c-phase current obtained by simulating the SVPWM injection type without the harmonic current suppression algorithm. Figure 8a to Figure 8e This is a schematic diagram of traditional SVPWM simulation analysis. Figure 8a The schematic diagram of the three-phase grid-side current obtained by traditional SVPWM simulation. Figure 8b The DC side voltage schematic diagram obtained by traditional SVPWM simulation. Figure 8c This is the schematic diagram of the FFT analysis of the a-phase current obtained by traditional SVPWM simulation. Figure 8d This is the schematic diagram of the FFT analysis of the b-phase current obtained by traditional SVPWM simulation. Figure 8e Schematic diagram of FFT analysis of c-phase current obtained by traditional SVPWM simulation.

[0121] Table 1 Summary of simulation data for three modulation algorithms

[0122] SVPWM with suppression algorithm SVPWM without suppression algorithm Traditional SVPWM a-phase current Thd(%) 5.83 6.48 5.59 b-phase current Thd(%) 5.30 6.76 6.00 c-phase current Thd(%) 5.47 6.90 6.25 Phase a 3rd harmonic current (%) 0.85 4.19 2.71 b phase 3rd harmonic current (%) 0.67 4.35 2.97 c phase 3rd harmonic current (%) 0.83 4.01 2.65 A phase current effective value (A) 59.58 60.4 61.17 b-phase current effective value (A) 60.54 59.65 59.39 C phase current effective value (A) 59.36 59.37 58.73 A phase fundamental power factor angle 0.5° 0.1° 0.3° Phase b fundamental power factor angle 239.7° 239.3° 238.5° Phase C fundamental power factor angle 119.3° 120.3° 120.9°

[0123] Please refer to Fig. 9 , Fig. 9 This is a schematic diagram of the structure of a rectifier control system provided in this application, and the rectifier control system includes:

[0124] The first acquisition module 1 is used to obtain the phase voltage of each phase of the rectifier grid side in the current power frequency cycle, determine the reference phase voltage among all phase voltages, and determine the phase voltage other than the reference phase voltage as the phase voltage to be adjusted;

[0125] Correction module 2, used for correcting each phase voltage to be adjusted so that the amplitude of the phase voltage of each phase after correction is balanced, and calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage;

[0126] A second acquisition module 3 is used to acquire a compensation phase voltage corresponding to each phase voltage to be adjusted;

[0127] The modulation module 4 is used to perform SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages.

[0128] It can be seen that in the rectifier control system provided by the present embodiment, the reference phase voltage and the phase voltage to be adjusted in the phase voltage of each phase of the current power frequency cycle of the rectifier are first determined, and each phase voltage to be adjusted is corrected so that the amplitude of the phase voltage of each phase after correction is balanced, and then the reference phase voltage of each phase is calculated based on the phase voltage of each phase after correction, and the compensation phase voltage of each phase to be adjusted is calculated. The present application superimposes the compensation phase voltage on the reference phase voltage of the corresponding phase and combines it with the zero-sequence voltage for SVPWM modulation, so that the calculated conduction time of the three-phase switch tube is more accurate, thereby suppressing the harmonic current caused by the imbalance of the grid-side voltage amplitude.

[0129] As an optional embodiment, the process of determining the reference phase voltage among all phase voltages includes:

[0130] The phase voltage with the smallest peak voltage among all phase voltages is determined as the reference phase voltage.

[0131] As an optional embodiment, the process of correcting each phase voltage to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced includes:

[0132] Obtaining correction parameters of the current power frequency cycle, where the correction parameters are determined based on the phase voltages of each phase in the previous power frequency cycle;

[0133] Each phase voltage to be adjusted is corrected by using the correction parameters so that the amplitudes of the phase voltages of each phase after correction are balanced.

[0134] As an optional embodiment, the rectifier control system further includes:

[0135] The first calculation module is used to calculate the correction parameter of the phase to be adjusted corresponding to each phase voltage to be adjusted in the next power frequency cycle through a first relationship. The first relationship is:

[0136] Among them, E i is the peak voltage of the i-th phase voltage to be adjusted, k i is the correction parameter of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted in the next power frequency cycle, E r is the peak voltage of the reference phase voltage.

[0137] As an optional embodiment, the acquisition module is specifically used for:

[0138] The compensation phase voltage corresponding to each phase voltage to be adjusted is calculated by the second relational expression, wherein the second relational expression is u icom =p(1-1 / K i )E pi ;

[0139] Among them, p is the compensation coefficient, K iis the correction parameter of the i-th phase voltage to be adjusted, E pi is the i-th phase voltage to be adjusted, u icom is the compensation phase voltage corresponding to the i-th phase voltage to be adjusted.

[0140] As an optional embodiment, the rectifier control system further includes:

[0141] The second calculation module is used to determine the maximum reference phase voltage and the minimum reference phase voltage among all reference phase voltages, and calculate the zero-sequence voltage through a third relationship. The third relationship is:

[0142] in, is the zero sequence voltage, is the maximum reference phase voltage, is the minimum reference phase voltage.

[0143] As an optional embodiment, the modulation module 4 is specifically used for:

[0144] Obtain the turn-on time of the switch tube of each phase of the rectifier through the fourth relational expression, and control the corresponding switch tube of each phase based on the turn-on time;

[0145] The fourth relation is

[0146] in, u icom are the reference phase voltage and compensation phase voltage corresponding to the i-th phase voltage to be adjusted, T icomp is the turn-on time of the switch tube of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted, is the reference phase voltage corresponding to the reference phase voltage, T rcomp is the turn-on time of the switch tube of the reference phase corresponding to the reference phase voltage, is the zero sequence voltage, T s is the carrier period, U dc is the output voltage.

[0147] On the other hand, the present application also provides a rectifier control device, comprising:

[0148] Memory for storing computer programs;

[0149] A processor is used to implement the steps of the rectifier control method described in any one of the embodiments above when executing a computer program.

[0150] Specifically, the memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and computer-readable instructions, and the internal memory provides an environment for the operation of the operating system and computer-readable instructions in the non-volatile storage medium. When the processor executes the computer program stored in the memory, the following steps can be implemented: obtaining the phase voltage of each phase on the grid side of the rectifier in the current power frequency cycle, determining the reference phase voltage among all phase voltages, and determining the phase voltages other than the reference phase voltage as the phase voltage to be adjusted; correcting each phase voltage to be adjusted so that the amplitude of the phase voltage of each phase after correction is balanced, and calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage; obtaining the compensation phase voltage corresponding to each phase voltage to be adjusted; and performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all compensation phase voltages.

[0151] It can be seen that in this embodiment, the reference phase voltage and the phase voltage to be adjusted in the phase voltage of each phase of the current power frequency cycle of the rectifier are first determined, and each phase voltage to be adjusted is corrected to balance the amplitude of the phase voltage of each phase after correction, and then the reference phase voltage of each phase is calculated based on the phase voltage of each phase after correction, and the compensation phase voltage of each phase to be adjusted is calculated. The present application superimposes the compensation phase voltage on the reference phase voltage of the corresponding phase and combines it with the zero-sequence voltage for SVPWM modulation, so that the calculated conduction time of the three-phase switch tube is more accurate, thereby suppressing the harmonic current caused by the imbalance of the grid-side voltage amplitude.

[0152] As an optional embodiment, when the processor executes the computer subroutine stored in the memory, the following steps may be implemented: determining the phase voltage with the smallest peak voltage among all phase voltages as the reference phase voltage.

[0153] As an optional embodiment, when the processor executes a computer subroutine stored in the memory, the following steps can be implemented: obtaining correction parameters for the current power frequency cycle, the correction parameters being determined based on the phase voltages of each phase in the previous power frequency cycle; and correcting each phase voltage to be adjusted using the correction parameters so that the amplitudes of the phase voltages of each phase after correction are balanced.

[0154] As an optional embodiment, when the processor executes the computer subroutine stored in the memory, the following steps may be implemented: the correction parameter of the phase to be adjusted corresponding to each phase voltage to be adjusted in the next power frequency cycle is calculated by the first relational expression, and the first relational expression is: Among them, E i is the peak voltage of the i-th phase voltage to be adjusted, k i is the correction parameter of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted in the next power frequency cycle, E r is the peak voltage of the reference phase voltage.

[0155] As an optional embodiment, when the processor executes the computer subroutine stored in the memory, the following steps may be implemented: calculating the compensation phase voltage corresponding to each phase voltage to be adjusted by the second relational expression, wherein the second relational expression is u icom =p(1-1 / K i )E pi ; Among them, p is the compensation coefficient, K i is the correction parameter of the i-th phase voltage to be adjusted, E pi is the i-th phase voltage to be adjusted, u icom is the compensation phase voltage corresponding to the i-th phase voltage to be adjusted. As an optional embodiment, when the processor executes the computer subroutine stored in the memory, the following steps can be implemented: determining the maximum reference phase voltage and the minimum reference phase voltage among all reference phase voltages; calculating the zero-sequence voltage through the third relational expression, the third relational expression is in, is the zero sequence voltage, is the maximum reference phase voltage, is the minimum reference phase voltage.

[0156] As an optional embodiment, when the processor executes the computer subroutine stored in the memory, the following steps may be implemented: obtaining the turn-on time of the switch tube of each phase of the rectifier through the fourth relational expression, and controlling the corresponding switch tube of each phase based on the turn-on time; the fourth relational expression is in, u icom are the reference phase voltage and compensation phase voltage corresponding to the i-th phase voltage to be adjusted, T icomp is the turn-on time of the switch tube of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted, is the reference phase voltage corresponding to the reference phase voltage, T rcomp is the turn-on time of the switch tube of the reference phase corresponding to the reference phase voltage, is the zero sequence voltage, T s is the carrier period, U dc is the output voltage.

[0157] Based on the above embodiment, as a preferred implementation, the rectifier control device further includes:

[0158] The input interface is connected to the processor and is used to obtain externally imported computer programs, parameters and instructions, and save them to the memory under the control of the processor. The input interface can be connected to an input device to receive parameters or instructions manually input by the user. The input device can be a touch layer covered on the display screen, or a button, trackball or touchpad set on the terminal housing.

[0159] The display unit is connected to the processor and is used to display the data sent by the processor. The display unit can be a liquid crystal display or an electronic ink display.

[0160] The network port is connected to the processor and is used to communicate with external terminal devices. The communication technology used for the communication connection can be a wired communication technology or a wireless communication technology, such as mobile high-definition link technology (MHL), universal serial bus (USB), high-definition multimedia interface (HDMI), wireless fidelity technology (WiFi), Bluetooth communication technology, low-power Bluetooth communication technology, communication technology based on IEEE802.11s, etc.

[0161] On the other hand, the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the rectifier control method described in any one of the above embodiments are implemented.

[0162] Specifically, the present application also provides a computer-readable storage medium, which may include: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, and other media that can store program codes. The storage medium stores a computer program, and when the computer program is executed by the processor, the following steps are implemented: obtaining the phase voltage of each phase on the grid side of the current power frequency cycle rectifier, determining the reference phase voltage among all phase voltages, and determining the phase voltage other than the reference phase voltage as the phase voltage to be adjusted; correcting each phase voltage to be adjusted so that the amplitude of the phase voltage of each phase after correction is balanced, and calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage; obtaining the compensation phase voltage corresponding to each phase voltage to be adjusted; and performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase, and all the compensation phase voltages.

[0163] It can be seen that in this embodiment, the reference phase voltage and the phase voltage to be adjusted in the phase voltage of each phase of the current power frequency cycle of the rectifier are first determined, and each phase voltage to be adjusted is corrected to balance the amplitude of the phase voltage of each phase after correction, and then the reference phase voltage of each phase is calculated based on the phase voltage of each phase after correction, and the compensation phase voltage of each phase to be adjusted is calculated. The present application superimposes the compensation phase voltage on the reference phase voltage of the corresponding phase and combines it with the zero-sequence voltage for SVPWM modulation, so that the calculated conduction time of the three-phase switch tube is more accurate, thereby suppressing the harmonic current caused by the imbalance of the grid-side voltage amplitude.

[0164] As an optional embodiment, when the computer subroutine stored in the computer-readable storage medium is executed by the processor, the following steps may be specifically implemented: determining the phase voltage with the smallest peak voltage among all phase voltages as the reference phase voltage.

[0165] As an optional embodiment, when the computer subroutine stored in the computer-readable storage medium is executed by the processor, the following steps can be specifically implemented: obtaining the correction parameters of the current power frequency cycle, the correction parameters are determined based on the phase voltages of each phase in the previous power frequency cycle; correcting each phase voltage to be adjusted by the correction parameters so that the amplitudes of the phase voltages of each phase after correction are balanced.

[0166] As an optional embodiment, when the computer subroutine stored in the computer-readable storage medium is executed by the processor, the following steps can be specifically implemented: the correction parameter of the phase to be adjusted corresponding to each phase voltage to be adjusted in the next power frequency cycle is calculated by the first relational expression, and the first relational expression is: Among them, E i is the peak voltage of the i-th phase voltage to be adjusted, k i is the correction parameter of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted in the next power frequency cycle, E r is the peak voltage of the reference phase voltage.

[0167] As an optional embodiment, when the computer subroutine stored in the computer-readable storage medium is executed by the processor, the following steps may be specifically implemented:

[0168] The compensation phase voltage corresponding to each phase voltage to be adjusted is calculated by the second relational expression, wherein the second relational expression is u icom =p(1-1 / K i )E pi ; Among them, p is the compensation coefficient, K i is the correction parameter of the i-th phase voltage to be adjusted, E pi is the i-th phase voltage to be adjusted, u icom is the compensation phase voltage corresponding to the i-th phase voltage to be adjusted.

[0169] As an optional embodiment, when the computer subroutine stored in the computer-readable storage medium is executed by the processor, the following steps can be specifically implemented: determining the maximum reference phase voltage and the minimum reference phase voltage among all reference phase voltages; calculating the zero-sequence voltage by a third relational expression, the third relational expression being: in, is the zero sequence voltage, is the maximum reference phase voltage, is the minimum reference phase voltage.

[0170] As an optional embodiment, when the computer subroutine stored in the computer-readable storage medium is executed by the processor, the following steps can be specifically implemented: obtaining the turn-on time of the switch tube of each phase of the rectifier through the fourth relationship, and controlling the corresponding switch tube of each phase based on the turn-on time; the fourth relationship is in, u icom are the reference phase voltage and compensation phase voltage corresponding to the i-th phase voltage to be adjusted, T icomp is the turn-on time of the switch tube of the phase to be adjusted corresponding to the i-th phase voltage to be adjusted, is the reference phase voltage corresponding to the reference phase voltage, T rcomp is the turn-on time of the switch tube of the reference phase corresponding to the reference phase voltage, is the zero sequence voltage, T s is the carrier period, U dc is the output voltage.

[0171] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0172] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A rectifier control method, characterized in that: include: Obtaining the phase voltage of each phase on the grid side of the rectifier in the current power frequency cycle, determining a reference phase voltage among all the phase voltages, and determining the phase voltages except the reference phase voltage as the phase voltage to be adjusted; Correcting each of the phase voltages to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced, and calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage; Obtaining a compensation phase voltage corresponding to each phase voltage to be adjusted; Performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages; The process of correcting each of the phase voltages to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced includes: Get the correction parameters of the current power frequency cycle; Correcting each of the phase voltages to be adjusted by using the correction parameter so that the amplitudes of the phase voltages of the phases after correction are balanced; The rectifier control method further includes: The correction parameter of the phase to be adjusted corresponding to each phase voltage to be adjusted in the next power frequency cycle is calculated by the first relational expression, wherein the first relational expression is: ; in, E i For the i The peak voltage of the phase voltage to be adjusted, k i For the i The correction parameter of the phase to be adjusted corresponding to the phase voltage to be adjusted in the next power frequency cycle, E r is the peak voltage of the reference phase voltage.

2. The rectifier control method according to claim 1, characterized in that: The process of determining the reference phase voltage among all the phase voltages comprises: A phase voltage having the smallest peak voltage among all the phase voltages is determined as a reference phase voltage.

3. The rectifier control method according to claim 1, characterized in that: The process of obtaining the compensation phase voltage corresponding to each phase voltage to be adjusted includes: The compensation phase voltage corresponding to each phase voltage to be adjusted is calculated by a second relational expression, wherein the second relational expression is: ; in, p is the compensation coefficient, For the i The correction parameters of the phase voltage to be adjusted, For the i The phase voltage to be adjusted, u icom For the i The compensation phase voltage corresponding to the phase voltage to be adjusted.

4. The rectifier control method according to claim 1, characterized in that: After respectively calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage, the rectifier control method further includes: determining a maximum reference phase voltage and a minimum reference phase voltage among all the reference phase voltages; The zero-sequence voltage is calculated by a third relational expression, which is: ; in, is the zero-sequence voltage, is the maximum reference phase voltage, is the minimum reference phase voltage.

5. The rectifier control method according to any one of claims 1 to 4, characterized in that: The process of performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages includes: Obtaining the turn-on time of the switch tube of each phase of the rectifier through the fourth relationship, and controlling the corresponding switch tube of each phase based on the turn-on time; The fourth relation is ; in, , The first i The reference phase voltage and the compensation phase voltage corresponding to the phase voltage to be adjusted are: For the i The conduction time of the switch tube of the phase to be adjusted corresponding to the phase voltage to be adjusted, is the reference phase voltage corresponding to the reference phase voltage, is the turn-on time of the switch tube of the reference phase corresponding to the reference phase voltage, is the zero-sequence voltage, is the carrier period, is the output voltage.

6. A rectifier control system, characterized in that: include: A first acquisition module is used to acquire the phase voltage of each phase on the grid side of the rectifier in the current power frequency cycle, determine the reference phase voltage among all the phase voltages, and determine the phase voltages except the reference phase voltage as the phase voltage to be adjusted; A correction module, used for correcting each of the phase voltages to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced, and respectively calculating the reference phase voltage of each phase based on the corrected phase voltage and the reference phase voltage; A second acquisition module, used for acquiring a compensation phase voltage corresponding to each phase voltage to be adjusted; A modulation module, used for performing SVPWM modulation on the rectifier according to the zero-sequence voltage, the reference phase voltage of each phase and all the compensation phase voltages; The process of correcting each of the phase voltages to be adjusted so that the amplitudes of the phase voltages of each phase after correction are balanced includes: Get the correction parameters of the current power frequency cycle; Correcting each of the phase voltages to be adjusted by using the correction parameter so that the amplitudes of the phase voltages of the phases after correction are balanced; The rectifier control system also includes: The first calculation module is used to calculate the correction parameter of the phase to be adjusted corresponding to each phase voltage to be adjusted in the next power frequency cycle through a first relationship, wherein the first relationship is: ; in, E i For the i The peak voltage of the phase voltage to be adjusted, k i For the i The correction parameter of the phase to be adjusted corresponding to the phase voltage to be adjusted in the next power frequency cycle, E r is the peak voltage of the reference phase voltage.

7. A rectifier control device, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the rectifier control method according to any one of claims 1 to 5 when executing the computer program.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the rectifier control method according to any one of claims 1 to 5 are implemented.

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