A power control system and method for a high-power flyback inverter

Abstract

The application discloses a power control system and method of a high-power flyback inverter, wherein the high-power flyback inverter is composed of three parallel flyback converters, and the power control system comprises a quadrature signal generation module, a coordinate transformation module, a power calculation module, a power control module, a reference voltage generation module, a voltage and current control module, an inverse transformation module, a sine pulse width modulation module and a zero-crossing comparison module. The application combines a linear active disturbance rejection control method and a flyback inverter power control method, combines the disturbance rejection characteristics of a linear active disturbance rejection controller and the instantaneous power tracking characteristics of a power control method, and greatly improves the anti-disturbance ability of the high-power flyback inverter power control method. The application can be widely applied to the technical field of flyback inverter control.

Description

Technical Field

[0001] This invention relates to the field of flyback inverter control technology, and in particular to a power control system and method for a high-power flyback inverter. Background Technology

[0002] Flyback inverters are widely used in photovoltaic power generation systems due to their advantages such as simple structure, low cost, small size and easy control. However, their power is relatively low. To cope with high-power applications, high-power flyback inverters are required.

[0003] Power control is a crucial control function of inverter systems. Traditional inverter power control methods often employ highly accurate PI controllers, which can achieve zero steady-state error tracking. However, when faced with large power surges and other disturbances, they frequently produce excessive overshoot and vibration, resulting in less than ideal control performance. Summary of the Invention

[0004] In order to at least partially solve one of the technical problems existing in the prior art, the purpose of this invention is to provide a power control system and method for a high-power flyback inverter.

[0005] The technical solution adopted in this invention is:

[0006] A power control system for a high-power flyback inverter includes:

[0007] The orthogonal signal generation module is used to acquire the grid-connected voltage signal v. o and grid-connected current signal i o According to the grid-connected voltage signal v o and grid-connected current signal i o Generate two sets of orthogonal signals i1 and i2, v1 and v2;

[0008] The coordinate transformation module is used to obtain the d-axis current signal i based on two sets of orthogonal signals i1 and i2, v1 and v2. d and voltage signal v d q-axis current signal i q and voltage signal v q ;

[0009] The power calculation module is used to calculate the power based on the current signal i. d and i q Voltage signal v d and v q To obtain the instantaneous active power P and instantaneous reactive power Q;

[0010] The power control module is used to obtain the reference voltage scalar v and angular frequency ω based on the instantaneous active power P and instantaneous reactive power Q.

[0011] The reference voltage generation module is used to obtain the d-axis voltage reference signal v based on the reference voltage scalar v and the angular frequency ω. dref and q-axis voltage reference signal v qref ;

[0012] The voltage and current control module is used to control the voltage based on the d-axis voltage reference signal v. dref and q-axis voltage reference signal v qref Obtain the d-axis control quantity u d and q-axis control quantity u q ;

[0013] The inverse transformation module is used to transform the d-axis control quantity u. d and q-axis control quantity u q Obtain control quantity u a u b and u c ;

[0014] The sinusoidal pulse width modulation module is used to adjust the control quantity u. a u b and u c , to obtain the signals used to control the three primary-side main switches;

[0015] The zero-crossing comparison module is used to compare the control quantity u. a u b and u c To obtain signals used to control the inverter;

[0016] The high-power flyback inverter includes three parallel flyback converters.

[0017] Furthermore, the orthogonal signal generation module is implemented using a second-order generalized integrator, where i1 = i o i2 phase lags the grid-connected current signal i1 by 90°; v1 = v o The phase of v2 lags behind the grid-connected voltage signal v1 by 90°.

[0018] Furthermore, the coordinate transformation module is specifically used to perform coordinate transformation on the two sets of orthogonal signals i1 and i2, v1 and v2, and the 0 signal respectively, transforming them from the three-phase abc coordinate system to the two-phase synchronous rotating (dq) coordinate system. Specifically, the voltage signal v on the d-axis is obtained based on the orthogonal signals v1 and v2. d and the voltage signal v on the q-axis q The expression is:

[0019]

[0020] In the formula, v a Indicates signals v1, v b Indicates signals v2, v cThis represents a 0 signal.

[0021] Furthermore, the expressions for the instantaneous active power P and instantaneous reactive power Q are as follows:

[0022]

[0023] Right now:

[0024]

[0025] Furthermore, the power control module includes a power differential unit and a first active disturbance rejection controller;

[0026] The power difference unit is used to compare the instantaneous active power P with the active power reference value P. ref The difference is used to obtain the active power error; and the instantaneous reactive power Q is compared with the reactive power reference value Q. ref The difference is calculated to obtain the reactive power error;

[0027] The first active disturbance rejection controller is used to adjust the active power error to obtain the angular frequency increment, and add the rated angular frequency to obtain the angular frequency ω; and to adjust the reactive power error to obtain the voltage amplitude increment, and add the rated voltage amplitude to obtain the reference voltage scalar v.

[0028] Furthermore, the reference voltage generation module includes an integration unit, a sine calculation unit, a second-order generalized integrator, and a coordinate transformation unit;

[0029] The integrator unit is used to perform time integration on the angular frequency ω to obtain phase information ωt;

[0030] The sine calculation is used to multiply the phase information ωt by the reference voltage scalar v to obtain a sinusoidal voltage reference signal v'. ref υ′ ref =υsin(ωt);

[0031] The second-order generalized integrator is used to determine the voltage reference signal v'. ref Two orthogonal voltage signals v are obtained. a and v b , where v a =v' ref v b Phase lag v a 90°;

[0032] The coordinate transformation unit is used to transform v a v b By performing coordinate transformation on the 0 signal, the d-axis voltage reference signal v is obtained. dref and q-axis voltage reference signal v qref .

[0033] Furthermore, the voltage and current control module includes a voltage differential unit, a second active disturbance rejection controller, a current differential unit, and a third active disturbance rejection controller;

[0034] The voltage difference unit is used to convert the d-axis voltage reference signal v dref Voltage signal v along the d-axis d The difference is used to obtain the first voltage error signal; and the q-axis voltage reference signal v is used to obtain the first voltage error signal. qref voltage signal v along the q-axis q The difference is calculated to obtain the second voltage error signal;

[0035] The second active disturbance rejection controller is used to adjust the first voltage error signal to obtain the d-axis current reference signal i. dref ; and adjust the second voltage error signal to obtain the q-axis current reference signal i. qref ;

[0036] The current subtraction unit is used to convert the d-axis current reference signal i dref Current signal i along the d-axis d The difference is calculated to obtain the first current error signal; and the q-axis current reference signal i is calculated. qref Current signal i along the q-axis q The difference is calculated to obtain the second voltage error signal;

[0037] The third active disturbance rejection controller is used to adjust the first current error signal to obtain the d-axis control quantity u. d ; and adjust the second current error signal to obtain the q-axis control quantity u. q .

[0038] Furthermore, the inverse transformation module is specifically used to transform the d-axis control quantity u d and q-axis control quantity u q Perform the inverse coordinate transformation, transforming from the synchronous rotating coordinate system to the abc coordinate system, to obtain the control variables u corresponding to the abc axes. a u b and u c ;

[0039] The expression for coordinate transformation is as follows:

[0040]

[0041] Furthermore, each of the flyback converters includes a primary-side main switch, and the primary-side main switches on each flyback converter are turned on sequentially according to a 120° phase difference.

[0042] The high-power flyback inverter also includes:

[0043] DC input terminal with voltage-regulating capacitor C;

[0044] An inverter is used to convert the sinusoidal half-wave current output from three parallel flyback converters into alternating current.

[0045] LC filters are used to filter out harmonics to improve the quality of grid-connected current.

[0046] Another technical solution adopted in this invention is:

[0047] A power control method for a high-power flyback inverter includes the following steps:

[0048] Collect grid-connected voltage signal v o and grid-connected current signal i o According to the grid-connected voltage signal v o and grid-connected current signal i o Generate two sets of orthogonal signals i1 and i2, v1 and v2;

[0049] Based on two sets of orthogonal signals i1 and i2, v1 and v2, obtain the d-axis current signal i. d and voltage signal v d q-axis current signal i q and voltage signal v q ;

[0050] According to the current signal i d and i q Voltage signal v d and v q To obtain the instantaneous active power P and instantaneous reactive power Q;

[0051] Based on the instantaneous active power P and instantaneous reactive power Q, obtain the reference voltage scalar v and angular frequency ω;

[0052] Obtain the d-axis voltage reference signal v based on the reference voltage scalar v and the angular frequency ω. dref and q-axis voltage reference signal v qref ;

[0053] Based on the d-axis voltage reference signal v dref and q-axis voltage reference signal v qref Obtain the d-axis control quantity u d and q-axis control quantity u q ;

[0054] Based on the d-axis control quantity u d and q-axis control quantity u q Obtain control quantity u a u b and u c ;

[0055] According to the control quantity u a u b and u c , to obtain the signals used to control the three primary-side main switches;

[0056] According to the control quantity u a u b and u c To obtain signals used to control the inverter;

[0057] The high-power flyback inverter includes three parallel flyback converters.

[0058] The beneficial effects of this invention are: this invention combines the anti-disturbance characteristics of a linear active disturbance rejection controller with the instantaneous power tracking characteristics of power control, which greatly improves the anti-disturbance capability of power control in high-power flyback inverters. Attached Figure Description

[0059] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following description is provided with accompanying drawings of the relevant technical solutions in the embodiments of the present invention or the prior art. It should be understood that the accompanying drawings described below are only for the purpose of clearly illustrating some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0060] Figure 1 This is the main circuit diagram of the high-power flyback inverter in this embodiment of the invention;

[0061] Figure 2 This is an equivalent circuit diagram of a power control system for a high-power flyback inverter in an embodiment of the present invention.

[0062] Figure 3 This is a structural diagram of the power control module based on active disturbance rejection in an embodiment of the present invention;

[0063] Figure 4 This is a structural diagram of the reference voltage generation module in an embodiment of the present invention;

[0064] Figure 5 This is a structural diagram of the voltage and current control module in an embodiment of the present invention. Detailed Implementation

[0065] The embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. The step numbers in the following embodiments are set only for ease of explanation, and there is no limitation on the order between the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0066] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0067] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0068] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0069] like Figure 1 As shown, this embodiment provides a high-power flyback inverter, including:

[0070] DC input terminal with voltage-regulating capacitor C;

[0071] The three-way parallel flyback converter is connected to the input terminal. The primary-side main switches S1 to S3 are turned on sequentially according to a 120° phase difference to convert the input DC signal into a sinusoidal half-wave form. Each flyback converter includes one primary-side main switch.

[0072] A single-phase power frequency inverter is used to convert the sinusoidal half-wave current output from three parallel flyback converters into AC current.

[0073] LC filters are used to filter out harmonics and improve the quality of grid-connected current.

[0074] Based on the above-mentioned high-power flyback inverter, such as Figure 2 As shown, this embodiment provides a power control system for a high-power flyback inverter, including:

[0075] The orthogonal signal generation module is used to acquire the grid-connected voltage signal v. o and grid-connected current signal i o According to the grid-connected voltage signal v o and grid-connected current signal i o Generate two sets of orthogonal signals i1 and i2, v1 and v2;

[0076] The coordinate transformation module is used to obtain the d-axis current signal i based on two sets of orthogonal signals i1 and i2, v1 and v2. d and voltage signal v d q-axis current signal i q and voltage signal v q ;

[0077] The power calculation module is used to calculate the power based on the current signal i. d and i q Voltage signal v d and v q To obtain the instantaneous active power P and instantaneous reactive power Q;

[0078] The power control module is used to obtain the reference voltage scalar v and angular frequency ω based on the instantaneous active power P and instantaneous reactive power Q.

[0079] The reference voltage generation module is used to obtain the d-axis voltage reference signal v based on the reference voltage scalar v and the angular frequency ω. dref and q-axis voltage reference signal v qref ;

[0080] The voltage and current control module is used to control the voltage based on the d-axis voltage reference signal v. dref and q-axis voltage reference signal v qref Obtain the d-axis control quantity u d and q-axis control quantity u q ;

[0081] The inverse transformation module is used to transform the d-axis control quantity u. d and q-axis control quantity u q Obtain control quantity u a u b and u c ;

[0082] A sinusoidal pulse width modulation (SPWM) module is used to adjust the control quantity u. a u b and u c , to obtain the signals used to control the three primary-side main switches;

[0083] The zero-crossing comparison module is used to compare the control quantity u. a u b and u c To obtain the signals used to control the inverter.

[0084] See Figure 2 As an optional implementation, the orthogonal signal generation module uses a second-order generalized integrator (SOGI) to generate the acquired grid-connected voltage signal v. o and grid-connected current signal i o The input is a second-order generalized integrator (SOGI), which generates two sets of orthogonal signals i1 and i2, v1 and v2, where i1 = i o i2 phase lags i1 by 90°; v1 = v o v2 phase lags v1 by 90°.

[0085] See Figure 2 As an optional implementation, the coordinate transformation module (abc-dq) is used to convert the input signal in the abc coordinate system into a signal in the synchronous rotating coordinate system. Specifically, it performs coordinate transformation on the two sets of orthogonal signals i1 and i2, v1 and v2, and the 0 signal, transforming them from the three-phase abc coordinate system to the two-phase synchronous rotating (dq) coordinate system. The voltage signal v on the d-axis is obtained based on the orthogonal signals v1 and v2. d and the voltage signal v on the q-axis q The expression is:

[0086]

[0087] See Figure 2 As an optional implementation, the power calculation module, based on instantaneous power theory, is used to calculate instantaneous active power P and instantaneous reactive power Q. The dq-axis current signal i... d and i q Voltage signal v d and v q The input power calculation module outputs instantaneous active power P and instantaneous reactive power Q.

[0088] The expressions for P and Q are as follows:

[0089]

[0090] Right now:

[0091]

[0092] See Figure 2As an optional implementation, the power control module, based on a linear active disturbance rejection controller, is used to track instantaneous active power P and instantaneous reactive power Q, and outputs a reference voltage scalar v and angular frequency ω.

[0093] See Figure 3 The power control module includes a power differential unit and a first active disturbance rejection controller;

[0094] The power difference unit is used to compare the instantaneous active power P with the active power reference value P. ref The difference is used to obtain the active power error; and the instantaneous reactive power Q is compared with the reactive power reference value Q. ref The difference is calculated to obtain the reactive power error;

[0095] The first active disturbance rejection controller is used to adjust the active power error to obtain the angular frequency increment, and add the rated angular frequency to obtain the angular frequency ω; and to adjust the reactive power error to obtain the voltage amplitude increment, and add the rated voltage amplitude to obtain the reference voltage scalar v.

[0096] See Figure 2 As an optional implementation, the reference voltage generation module takes the reference voltage scalar v and angular frequency ω output by the power control module as input, and after reference voltage synthesis, orthogonal signal generation and coordinate transformation, generates and outputs the d-axis voltage reference signal v. dref and q-axis voltage reference signal v qref .

[0097] See Figure 4 The reference voltage generation module includes an integration unit, a sine calculation unit, a second-order generalized integrator, and a coordinate transformation unit.

[0098] The integrator unit is used to perform time integration on the angular frequency ω to obtain phase information ωt;

[0099] The sine calculation is used to multiply the phase information ωt by the reference voltage scalar v to obtain a sinusoidal voltage reference signal v'. ref υ′ ref =υsin(ωt);

[0100] The second-order generalized integrator is used to determine the voltage reference signal v'. ref Two orthogonal voltage signals v are obtained. a and v b , where v a =v' ref v b Phase lag v a 90°;

[0101] The coordinate transformation unit is used to transform va v b By performing coordinate transformation on the 0 signal, the d-axis voltage reference signal v is obtained. dref and q-axis voltage reference signal v qref .

[0102] See Figure 2 As an optional implementation, the voltage and current control module receives the d-axis voltage reference signal v. dref and q-axis voltage reference signal v qref The d-axis control quantity u is obtained and output after adjustment by the active disturbance rejection controller. d and q-axis control quantity u q .

[0103] See Figure 5 The voltage and current control module includes a voltage differential unit, a second active disturbance rejection controller, a current differential unit, and a third active disturbance rejection controller.

[0104] The voltage difference unit is used to convert the d-axis voltage reference signal v dref Voltage signal v along the d-axis d The difference is used to obtain the first voltage error signal; and the q-axis voltage reference signal v is used to obtain the first voltage error signal. qref voltage signal v along the q-axis q The difference is calculated to obtain the second voltage error signal;

[0105] The second active disturbance rejection controller is used to adjust the first voltage error signal to obtain the d-axis current reference signal i. dref ; and adjust the second voltage error signal to obtain the q-axis current reference signal i. qref ;

[0106] The current subtraction unit is used to convert the d-axis current reference signal i dref Current signal i along the d-axis d The difference is calculated to obtain the first current error signal; and the q-axis current reference signal i is calculated. qref Current signal i along the q-axis q The difference is calculated to obtain the second voltage error signal;

[0107] The third active disturbance rejection controller is used to adjust the first current error signal to obtain the d-axis control quantity u. d ; and adjust the second current error signal to obtain the q-axis control quantity u. q .

[0108] See Figure 2 As an optional implementation, the inverse transformation module (dq-abc) is used to transform the input control quantity u in the synchronous rotating coordinate system. d and u qConverted to control quantity u in the abc coordinate system a u b and u c .

[0109] The expression for coordinate transformation is as follows:

[0110]

[0111] See Figure 2 As an optional implementation, the control quantity u of the abc axis is... a u b and u c Sinusoidal pulse width modulation (SPWM) is performed separately to obtain the turn-on signals of switching transistors S1 to S3; the control quantity u of phase a is selected. a The zero-comparison module obtains the conduction signals of switching transistors S4 to S7.

[0112] This embodiment also provides a power control method for a high-power flyback inverter, including the following steps:

[0113] Step 1: First, acquire the grid-connected voltage signal v. o and grid-connected current signal i o The input is given to a second-order generalized integrator (SOGI) to generate two sets of orthogonal signals i1 and i2, v1 and v2, where i1 = i o i2 phase lags i1 by 90°; v1 = v o v2 phase lags v1 by 90°.

[0114] Step 2: Perform coordinate transformation on the two sets of orthogonal signals i1 and i2, v1 and v2, and 0 signal mentioned in Step 1, transforming them from the three-phase abc coordinate system to the two-phase synchronous rotating (dq) coordinate system, to obtain the d-axis current signal i. d and voltage signal v d ,q-axis current signal i q and voltage signal v q .

[0115] The coordinate transformation process is as follows:

[0116]

[0117] Step 3: Convert the dq-axis current signal i from Step 2... d and i q Voltage signal v d and v q The input power calculation module outputs instantaneous active power P and instantaneous reactive power Q.

[0118] The expressions for P and Q are as follows:

[0119]

[0120] Right now:

[0121]

[0122] Step 4: Input the instantaneous active power P and instantaneous reactive power Q obtained in Step 3 into the power control module, and adjust them through the active disturbance rejection controller to obtain the reference voltage scalar v and angular frequency ω.

[0123] The specific implementation process is as follows: Figure 3 As shown, the instantaneous active power P and instantaneous reactive power Q obtained from the power calculation module are input into the power control module and compared with the active power reference value P. ref and reactive power reference value Q ref The active power error and reactive power error are obtained by subtracting them respectively. The active power error is input to the disturbance rejection controller for adjustment to obtain the angular frequency increment. The rated angular frequency is added to obtain the given angular frequency ω. The reactive power error is input to the disturbance rejection controller for adjustment to obtain the voltage amplitude increment. The rated voltage amplitude is added to obtain the given voltage amplitude scalar v.

[0124] Step 5: Input the reference voltage scalar v and angular frequency ω obtained in Step 4 into the reference voltage generation module to obtain the d-axis voltage reference signal v. dref and q-axis voltage reference signal v qref .

[0125] The specific implementation process is as follows: Figure 4 As shown, the phase information, ωt, is obtained by integrating the angular frequency ω over time. The obtained phase information ωt is then input into the sine calculation module and multiplied by the reference voltage scalar v to obtain the sinusoidal waveform voltage reference signal v'. ref υ′ ref =υsin(ωt). Then v' ref Inputting the signal into a second-order generalized integrator yields two orthogonal voltage signals v. a and v b , where v a =v' ref v b Phase lag v a 90°. (The last part, "v", appears to be an unrelated fragment and is left untranslated.) a v b By performing coordinate transformation on the 0 signal, the d-axis voltage reference signal v is obtained. dref and q-axis voltage reference signal v qref .

[0126] Step 6: Convert the d-axis voltage reference signal v from Step 5... dref and q-axis voltage reference signal v qref The input voltage and current control module, through adjustment by the active disturbance rejection controller, obtains the d-axis control quantity u.d and q-axis control quantity u q .

[0127] The specific implementation process is as follows: Figure 5 As shown, the d-axis voltage reference signal v mentioned in step five... dref and q-axis voltage reference signal v qref With d-axis voltage signal v d and q-axis voltage signal v q The voltage error signals are obtained by subtracting the voltage signals, and then the d-axis current reference signal i is obtained by adjusting the signal i using an active disturbance rejection controller. dref and q-axis current reference signal i qref Then, respectively, compare with the d-axis current signal i d and q-axis current signal i q The difference between the current signals is used to obtain the respective current error signals, which are then adjusted by the active disturbance rejection controller to obtain the d-axis control quantity u. d and q-axis control quantity u q .

[0128] Step 7: Convert the d-axis control quantity u described in Step 6. d and q-axis control quantity u q Perform the inverse coordinate transformation, that is, transform from the synchronous rotating coordinate system to the abc coordinate system, to obtain the control variables u corresponding to the abc axes. a u b and u c .

[0129] The coordinate transformation process is as follows:

[0130]

[0131] Step 8: Select the abc axis control quantity u described in Step 7. a u b and u c Sinusoidal pulse width modulation (SPWM) is performed separately to obtain the turn-on signals of switching transistors S1 to S3; the control quantity u of phase a is selected. a The zero-comparison module obtains the conduction signals of switching transistors S4 to S7.

[0132] In summary, this invention realizes a power control method for a high-power flyback inverter based on active disturbance rejection (ADREM) technology. By combining the linear ADREM control method with the flyback inverter power control method, and integrating the disturbance rejection characteristics of the linear ADREM controller with the instantaneous power point tracking characteristics of the power control method, the disturbance rejection capability of the high-power flyback inverter power control method is improved.

[0133] In the foregoing description of this specification, references to terms such as "one embodiment," "another embodiment," or "some embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0134] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

[0135] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A power control system for a high-power flyback inverter, characterized in that, include: The orthogonal signal generation module is used to acquire grid-connected voltage signals. and grid-connected current signal According to the grid-connected voltage signal and grid-connected current signal Generate two sets of orthogonal signals and , and ; The coordinate transformation module is used to transform two sets of orthogonal signals. and , and Obtain the current signal along the d-axis. and voltage signal q-axis current signal and voltage signal ; The power calculation module is used to calculate the power based on the current signal. and Voltage signal and To obtain the instantaneous active power P and instantaneous reactive power Q; The power control module is used to obtain the reference voltage scalar v and angular frequency based on the instantaneous active power P and instantaneous reactive power Q. ; The reference voltage generation module is used to generate a reference voltage scalar v and an angular frequency. Obtain the d-axis voltage reference signal and q-axis voltage reference signal ; The voltage and current control module is used to control the voltage based on the d-axis voltage reference signal. and q-axis voltage reference signal Obtain d-axis control quantity and q-axis control quantity ; The inverse transformation module is used to control the d-axis quantity. and q-axis control quantity Obtain control quantity , and ; The sinusoidal pulse width modulation module is used to adjust the control quantity. , and , to obtain the signals used to control the three primary-side main switches; The zero-crossing comparison module is used to compare the control quantity. , and To obtain signals used to control the inverter; The high-power flyback inverter includes three parallel flyback converters. The voltage and current control module includes a voltage differential unit, a second active disturbance rejection controller, a current differential unit, and a third active disturbance rejection controller. The voltage difference unit is used to convert the d-axis voltage reference signal Voltage signal with d-axis The difference is calculated to obtain the first voltage error signal; and the q-axis voltage reference signal is calculated. voltage signal with q axis The difference is calculated to obtain the second voltage error signal; The second active disturbance rejection controller is used to adjust the first voltage error signal to obtain the d-axis current reference signal. ; and by adjusting the second voltage error signal, the q-axis current reference signal is obtained. ; The current subtraction unit is used to convert the d-axis current reference signal Current signal with d-axis The difference is used to obtain the first current error signal; and the q-axis current reference signal is used to obtain the second current error signal. Current signal along the q-axis The difference is calculated to obtain the second voltage error signal; The third active disturbance rejection controller is used to adjust the first current error signal to obtain the d-axis control quantity. ; and adjust the second current error signal to obtain the q-axis control quantity. .

2. The power control system for a high-power flyback inverter according to claim 1, characterized in that, The orthogonal signal generation module is implemented using a second-order generalized integrator, wherein... = , Phase lag grid-connected current signal 90°; = , Phase lag grid-connected voltage signal 90°.

3. The power control system for a high-power flyback inverter according to claim 1, characterized in that, The coordinate transformation module is specifically used to transform two sets of orthogonal signals. and , and The coordinate transformation is performed on the zero-sequence signal and the coordinate system, transforming it from the three-phase abc coordinate system to the two-phase synchronous rotating coordinate system; among which, according to the orthogonal signal... and Obtain the voltage signal along the d-axis and q-axis voltage signal The expression is: In the formula, Indicates signal , Indicates signal , This indicates a 0 signal.

4. The power control system for a high-power flyback inverter according to claim 1, characterized in that, The expressions for the instantaneous active power P and instantaneous reactive power Q are as follows: Right now: 。 5. The power control system for a high-power flyback inverter according to claim 1, characterized in that, The power control module includes a power differential unit and a first active disturbance rejection controller; The power difference unit is used to compare the instantaneous active power P with the active power reference value. The difference is used to obtain the active power error; and the instantaneous reactive power Q is compared with the reactive power reference value. The difference is calculated to obtain the reactive power error; The first active disturbance rejection controller is used to adjust the active power error to obtain the angular frequency increment, and then add the rated angular frequency to obtain the angular frequency. ; In addition, the reactive power error is adjusted to obtain the voltage amplitude increment, which is then added to the rated voltage amplitude to obtain the reference voltage scalar v.

6. The power control system for a high-power flyback inverter according to claim 1, characterized in that, The reference voltage generation module includes an integration unit, a sine calculation unit, a second-order generalized integrator, and a coordinate transformation unit. The integrator unit is used for angular frequency Phase information is obtained by performing time integration. ; The sine calculation is used to extract phase information. Multiplying this by the reference voltage scalar v yields a sinusoidal voltage reference signal. , ; The second-order generalized integrator is used to adjust the voltage reference signal. This yields two orthogonal voltage signals. and ,in = , Phase lag 90°; The coordinate transformation unit is used to transform... , By performing coordinate transformation on the 0 signal, the d-axis voltage reference signal is obtained. and q-axis voltage reference signal .

7. The power control system for a high-power flyback inverter according to claim 1, characterized in that, The inverse transformation module is specifically used to convert the d-axis control quantity and q-axis control quantity Perform the inverse coordinate transformation, transforming from the synchronous rotating coordinate system to the abc coordinate system, to obtain the control variables corresponding to the abc three axes. , and ; The expression for coordinate transformation is as follows: 。 8. The power control system for a high-power flyback inverter according to claim 1, characterized in that, Each flyback converter includes a primary-side main switch, and the primary-side main switches on each flyback converter are turned on sequentially according to a 120° phase difference. The high-power flyback inverter also includes: DC input terminal with voltage-regulating capacitor C; An inverter is used to convert the sinusoidal half-wave current output from three parallel flyback converters into alternating current. LC filters are used to filter out harmonics to improve the quality of grid-connected current.

9. A power control method for a high-power flyback inverter, applied to the power control system described in any one of claims 1-8, characterized in that, Includes the following steps: Collect grid-connected voltage signals and grid-connected current signal According to the grid-connected voltage signal and grid-connected current signal Generate two sets of orthogonal signals and , and ; Based on two sets of orthogonal signals and , and Obtain the current signal along the d-axis. and voltage signal q-axis current signal and voltage signal ; Based on current signal and Voltage signal and To obtain the instantaneous active power P and instantaneous reactive power Q; Based on the instantaneous active power P and instantaneous reactive power Q, obtain the reference voltage scalar v and the angular frequency. ; Based on the reference voltage scalar v and the angular frequency Obtain the d-axis voltage reference signal and q-axis voltage reference signal ; Based on the d-axis voltage reference signal and q-axis voltage reference signal Obtain d-axis control quantity and q-axis control quantity ; Based on the d-axis control quantity and q-axis control quantity Obtain control quantity , and ; According to the control quantity , and , to obtain the signals used to control the three primary-side main switches; According to the control quantity , and To obtain signals used to control the inverter; The high-power flyback inverter includes three parallel flyback converters.

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