CN117914172B - Method, equipment and medium for designing control parameters of voltage loop of grid-formed inverter - Google Patents
Method, equipment and medium for designing control parameters of voltage loop of grid-formed inverter Download PDFInfo
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Abstract
The invention relates to the field of inverters, and discloses a method, equipment and medium for designing voltage loop control parameters of a grid-structured inverter. The method comprises the steps of establishing a network-structured inverter model based on an inductive current proportional feedback active damping and voltage resonance regulator; judging the size of the resonance frequency fr and 1/6 times of the sampling frequency fs; respectively aiming at two magnitude relation conditions, determining the corresponding relation between the number of the open-loop right half-plane poles of the system and the inductance current feedback coefficient Hi; deriving a constraint expression of the amplitude margin GM and the phase angle margin PM on the control parameters; deducing a constraint expression of the fundamental wave gain amplitude Tfo of the system on control parameters; setting expected GM, PM and Tfo according to the constraint expression, and drawing selectable areas of an open loop cut-off frequency fc and an inductance current feedback coefficient Hi; taking the appropriate fc and Hi from the selectable region, calculating a controller resonance coefficient Krv; and drawing a system gain baud chart according to the selected parameters, and checking whether the design requirement is met.
Description
Technical Field
The invention relates to the field of inverter control parameter design, in particular to a method, equipment and medium for designing voltage loop control parameters of a grid-structured inverter.
Background
In recent years, in order to cope with the problems of energy crisis, air pollution and the like, the new energy power generation ratio represented by wind power and photovoltaics in China is gradually increased. The Grid-connected inverter is an important interface device for realizing the access of the new energy power generation unit to the power Grid, and can be divided into a Grid-following (Grid-following) inverter and a Grid-forming (Grid-forming) inverter according to different control modes. Compared with a grid-type inverter, the grid-type inverter has the capability of simulating the external characteristics of a traditional synchronous generator and can provide inertial support for a power grid, so that the grid-type inverter is more suitable for a novel power system which selects a high-proportion new energy power generation unit.
The grid-connected inverter usually adopts an LC filter to filter out higher harmonics, and the LC filter has resonance problems, namely, at the resonance frequency, resonance peaks exist and phase jump is accompanied, so that the grid-connected inverter is easy to be unstable, and therefore, the resonance peaks need to be damped. Inductive current proportional feedback active damping is favored over passive damping because of its energy loss free and flexible and efficient characteristics. In addition, the output impedance of the grid-tied inverter presents non-passivity in certain frequency bands due to the influence of digital control delay, and therefore has the risk of unstable oscillation. In order to solve the problem, students find that under the control of a single voltage loop, the Proportional term in a Proportional-resonance (PR) voltage controller is removed, namely, a resonance voltage (R) controller is adopted, so that the passive frequency band of output impedance can be widened, and the stability of an inverter control system is improved.
However, the prior studies have not proposed a universal method for the optimized selection of the above-mentioned voltage controller parameters and inductor current feedback coefficients. In practical engineering application, a trial-and-error method is generally adopted to perform parameter design, so that the design efficiency is low, and the problems that the wide range of change of the power grid impedance cannot be adapted and the steady state and the dynamic performance of the system cannot be considered possibly are caused. If the parameters such as the voltage controller parameters and the inductance current feedback coefficients are unreasonable in design, the system is at risk of instability, and especially when the power grid suffers from a large disturbance fault, the unreasonable control parameter design can cause the system to lose stability directly and collapse.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a method, equipment and medium for designing voltage loop control parameters of a grid-built inverter, and aims to reduce trial and error process in the design of the grid-built inverter parameters, and simultaneously, the method is beneficial to analyzing system performance and optimizing closed loop control parameters, so that the system has ideal steady state and dynamic performance while effectively damping resonance peaks of an LC filter.
The invention provides a method for designing control parameters of a voltage loop of a grid-built inverter, which comprises the following steps:
Step S101, establishing a net-structured inverter mathematical model based on an inductance current proportional feedback active damping and voltage resonance regulator;
step S102, judging the magnitude relation between the resonant frequency f r and the sampling frequency f s which is 1/6 times of the resonant frequency f;
Step S103, respectively aiming at two cases f r＜fs/6 and f r≥fs/6, determining the corresponding relation between the number P of the open-loop right half plane poles of the system and an inductance current feedback coefficient H i;
Step S104, based on the number P of the open-loop right half-plane poles of the system, and combining with a Nyquist stability criterion, deriving a constraint expression of the amplitude margin GM and the phase angle margin PM on the control parameters of the voltage loop of the grid-formed inverter;
Step S105, deducing a constraint expression of fundamental wave gain amplitude T fo of the system on the control parameters of the voltage loop of the grid-connected inverter according to the steady-state error requirement of the system;
Step S106, according to the constraint expression of the voltage loop control parameters of the grid-formed inverter, setting a desired amplitude margin GM, a phase angle margin PM and a fundamental wave gain amplitude T fo, and drawing selectable areas of a system open loop cut-off frequency f c and an inductance current feedback coefficient H i;
Step S107, selecting a proper system open loop cut-off frequency f c and an inductance current feedback coefficient H i from the optional area, and calculating to obtain a controller resonance coefficient K rv;
Step S108, drawing a system gain baud chart according to the system open loop cut-off frequency f c and the inductance current feedback coefficient H i selected in the step S107, and checking whether the loop gain meets the design requirement.
Further, the voltage resonance regulator used in the step S101 is an R controller.
Further, in the above-mentioned step S103,
When f r＜fs/6, if the inductor current feedback coefficient H i satisfies:
Wherein, L f is the inductance value of the filter, f s is the sampling frequency, f r is the resonant frequency, and the number P of the right half plane poles of the open loop of the system is 0;
If the inductance current feedback coefficient H i satisfies:
the number P of the open loop right half plane poles of the system is 2;
When f r≥fs/6, for any inductance current feedback coefficient H i >0, the number of pole points P of the right half plane of the open loop of the system is 2.
Further, in the above-mentioned step S104,
When f r＜fs/6 and the number of the open-loop right half plane poles P=0 of the system, the amplitude margin GM 1 of the open-loop gain at f r is required to be more than 0dB;
when f r＜fs/6 and the number of the pole points of the right half plane of the open loop of the system is P=2, the amplitude margin GM 1 of the open loop gain at f r is required to be more than 0dB, and the amplitude margin GM 2 of the open loop gain at f s/6 is required to be less than 0dB;
When f r≥fs/6, the number of the pole points of the open-loop right half plane of the system is P=2, the amplitude margin GM 1 of the open-loop gain at f r is required to be smaller than 0dB, and the amplitude margin GM 2 of the open-loop gain at f s/6 is required to be larger than 0dB.
The constraint expression of the amplitude margin GM 1、GM2 on the inductor current feedback coefficient H i_GM1、Hi_GM2 is:
Wherein GM 1 is the amplitude margin of the open loop gain at f r, GM 2 is the amplitude margin of the open loop gain at f s/6, L f is the filter inductance value, f c is the system open loop cut-off frequency, f s is the sampling frequency, and f r is the resonant frequency;
The constraint expression of the phase angle margin PM of the open loop gain at the system open loop cut-off frequency f c on the inductor current feedback coefficient H i_PM is:
Wherein PM is the phase angle margin of the open loop gain at f c, f c is the system open loop cut-off frequency, T s is the sampling period, L f is the filter inductance value, and C f is the filter capacitance value.
Further, in the above step S105, the constraint expression of the fundamental gain amplitude T fo on the system open loop cut-off frequency f c_Tfo is:
Wherein T fo is fundamental wave gain amplitude, f o is fundamental wave frequency, and ζ is damping ratio of the controller.
Further, in the step S106, the selectable areas of the open loop cut-off frequency f c and the inductor current feedback coefficient H i are the areas surrounded by the constraint curves of H i_GM1、Hi_GM2、Hi_PM and f c_Tfo.
Further, in the step S107, the selected open loop cut-off frequency f c of the system is lower than the equivalent switching frequency f sw of 1/10; on the premise of ensuring a sufficient amplitude margin GM, a smaller H i is generally selected; the calculation formula of the controller resonance coefficient K rv is:
Where f c is the system open loop cut-off frequency.
Further, in the step S108, when the loop gain meets the design requirement, the parameter selection result of the open loop cut-off frequency f c, the inductance current feedback coefficient H i and the controller resonance coefficient K rv is output; when the loop gain does not meet the design requirement, the step S107 is returned to reselect the open loop cut-off frequency f c and the inductor current feedback coefficient H i.
The invention also provides a computer device which comprises a storage, a processor and a computer program stored on the storage and capable of running on the processor, wherein the computer program is executed by the processor to realize the method for designing the control parameters of the voltage loop of the grid-built inverter.
The invention also provides a computer storage medium, on which a computer program is stored, which when being executed by a processor, implements the above-mentioned method for designing the control parameters of the grid-built inverter voltage loop.
Compared with the prior art, the method for designing the voltage loop control parameters of the grid-formed inverter provided by the invention can not only effectively reduce the trial-and-error process in the parameter design of the grid-formed inverter, but also be beneficial to analyzing the system performance and optimizing the closed loop control parameters, so that the system has ideal steady-state and dynamic performance while effectively damping the resonance peak of the LC filter.
Drawings
Fig. 1 is a schematic diagram of a three-phase grid-structured inverter control structure.
Fig. 2 is a flowchart illustrating steps of a method for designing voltage loop control parameters of a grid-tied inverter according to the present invention.
Fig. 3 is a control block diagram of the three-phase grid-structured inverter in fig. 1.
Fig. 4 is a schematic diagram of an alternative region of the system open loop cut-off frequency f c and inductor current feedback coefficient H i for each constraint in the design example.
Fig. 5 is a system loop gain baud diagram in a design example.
Fig. 6 is a simulation waveform of the inverter in each state in the design example.
Detailed Description
The present invention will be described in further detail with reference to the drawings and the embodiments, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Fig. 1 is a schematic diagram of a three-phase grid-structured inverter control structure. As shown in fig. 1, the three-phase grid-formed inverter includes a power supply module 1, a three-phase inverter bridge module 2, an LC filter module 3, a utility grid module 4, and a controller module 5. The power module 1 comprises a direct current power supply V dc, and the three-phase inverter bridge module 2 comprises a switching tube and a freewheeling diode thereof; the LC filter module 3 comprises a filter inductance L f and a filter capacitance C f; the public power grid module 4 comprises a three-phase voltage source v g and an equivalent power grid impedance Z g; the controller module 5 includes a power synchronous controller, an output voltage controller G v (z), and an inductor current feedback coefficient H i as an inductor current proportional feedback active damping coefficient.
In the structure of fig. 1, the control system of the controller module 5 obtains an output voltage command v * o_αβ by adopting power synchronous control, and actively damps the resonance peak of the LC filter module 3 through a feedback inductor current i L_αβ.
As shown in fig. 2, the control parameter design method provided by the invention comprises the following steps:
Step S101, a net-structured inverter mathematical model based on the inductance current proportion feedback active damping and voltage resonance regulator is established. Specifically, according to the schematic diagram of the inverter control structure shown in fig. 1, a control block diagram thereof is shown in fig. 3. Wherein, G d(s) is 1.5 beat control delay, and the expression is:
Where T s is the sampling period and s is the complex variable.
G v(s) is a transfer function of a voltage controller, specifically an R controller in the invention, and the expression is as follows:
Wherein K rv is the controller resonance coefficient, omega 0 is the fundamental wave angular frequency, ζ is the controller damping ratio, and s is the complex variable.
Further, from fig. 3, the open loop gain T(s) of the control system can be derived as:
Wherein ω r is the resonant angular frequency of the LC filter, H i is the inductor current feedback coefficient, L f is the filter inductance value, and s is the complex variable.
In step S102, the magnitude relation between the resonant frequency f r and the sampling frequency f s which is 1/6 times of the resonant frequency is determined. Specifically, the size relationship between f r and f s/6 is compared, and the comparison can be divided into two cases of f r＜fs/6 and f r≥fs/6.
Step S103, respectively aiming at two cases f r＜fs/6 and f r≥fs/6, determining the corresponding relation between the number P of the open-loop right half plane poles of the system and the inductance current feedback coefficient H i. Specifically, the number P of the right half-plane poles of the open-loop system is different due to the magnitude relation between f r and f s/6 and the inductance current feedback coefficient H i, and the number P of the right half-plane poles of the open-loop system affects the stability margin constraint conditions in the subsequent steps, so the number P of the right half-plane poles of the open-loop system needs to be discussed in different situations.
When f r＜fs/6, if the inductor current feedback coefficient H i satisfies:
Wherein, L f is the inductance value of the filter, f s is the sampling frequency, f r is the resonant frequency, and the number P of the right half plane poles of the open loop of the system is 0;
If the inductance current feedback coefficient H i satisfies:
The number of open loop right half plane poles P of the system is 2.
When f r≥fs/6, for any inductance current feedback coefficient H i >0, the number of pole points P of the right half plane of the open loop of the system is necessarily 2.
Step S104, based on the number P of the open-loop right half-plane poles of the system, combining with a Nyquist stability criterion (Nyquist Stability Criterion), deriving a constraint expression of the amplitude margin GM and the phase angle margin PM on the voltage loop control parameters of the grid-connected inverter. Specifically, the constraint condition of the amplitude margin GM on the inductor current feedback coefficient H i is affected by the magnitude relation of f r and f s/6, and the number P of the right half-plane poles of the system open loop is different:
When f r＜fs/6, if the number of the pole points P=0 of the right half plane of the open loop of the system, the phase-frequency curve of the gain of the open loop of the system only passes through-180 degrees at f r, and according to the Nyquist stabilization criterion, the amplitude of the gain of the open loop at f r is required to be negative, so that the stability of the control system can be ensured, namely the amplitude margin GM 1 of the gain of the open loop at f r is more than 0dB;
if the number of the pole points P=2 of the right half plane of the open loop of the system, the phase-frequency curve of the gain of the loop of the open loop of the system passes through-180 degrees at the f r and the f s/6 respectively, and according to the Nyquist stability criterion, the amplitude of the gain of the loop of the open loop is required to be positive at the higher pass-through frequency and negative at the lower pass-through frequency, so that the stability of the control system can be ensured. That is, the magnitude margin GM 1 > 0dB at f r, the magnitude margin GM 2 < 0dB at f s/6, for the open loop gain is required;
When f r≥fs/6 is adopted, the number P of the pole points of the right half plane of the open loop of the system is certain to be 2, the phase-frequency curve of the gain of the open loop of the system respectively passes through-180 degrees at the f s/6 and the f r, the amplitude of the gain of the open loop is required to be positive at the higher crossing frequency and negative at the lower crossing frequency according to the Nyquist stability criterion, and therefore the stability of the control system can be ensured. That is, the magnitude margin GM 1 < 0dB at f r, the magnitude margin GM 2 > 0dB at f s/6, for the open loop gain is required.
The constraint expression of the amplitude margin GM 1 and GM 2 on the inductor current feedback coefficient H i_GM1、Hi_GM2 is:
wherein GM 1 is the amplitude margin of the open loop gain at f r, GM 2 is the amplitude margin of the open loop gain at f s/6, L f is the filter inductance value, f c is the system open loop cut-off frequency, f s is the sampling frequency, and f r is the resonant frequency.
Different from the constraint condition of the amplitude margin, the constraint condition of the phase angle margin PM on the control parameter of the voltage loop of the grid-structured inverter is not influenced by the magnitude relation of f r and f s/6 and the number P of the right half-plane poles of the open loop of the system, and the constraint expression of the phase angle margin PM of the open loop gain at the cut-off frequency f c of the open loop of the system on the feedback coefficient H i_PM of the inductance current is always as follows:
Wherein PM is the phase angle margin of the open loop gain at f c, f c is the system open loop cut-off frequency, T s is the sampling period, L f is the filter inductance value, and C f is the filter capacitance value.
And step 105, deriving a constraint expression of fundamental wave gain amplitude T fo of the system on the control parameters of the voltage loop of the grid-connected inverter according to the steady-state error requirement of the system. Specifically, by deriving an expression of the output voltage error, the steady-state error of the system is only related to the fundamental gain amplitude T fo, so that the constraint of the steady-state error of the system on the closed-loop parameter can be converted into the constraint of the fundamental gain amplitude T fo on the closed-loop parameter. The constraint expression of the fundamental wave gain amplitude T fo on the system open loop cut-off frequency f c_Tfo is specifically as follows:
wherein T fo is fundamental wave gain amplitude, f o is fundamental wave frequency, and ζ is controller damping ratio.
Step S106, according to the constraint expression of the voltage loop control parameters of the grid-structured inverter, setting a desired amplitude margin GM, a phase angle margin PM and a fundamental wave gain amplitude T fo, and drawing selectable areas of a system open loop cut-off frequency f c and an inductance current feedback coefficient H i. Specifically, the fundamental gain amplitude T fo is determined by the output voltage steady state error requirement; determining an amplitude margin GM according to the system stability and robustness requirements; the phase angle margin PM is determined by the system dynamic performance requirements. In general, T fo>40dB;GM1>3dB;GM2 < -3dB is generally required in order to ensure that the system has good steady state performance and dynamic performance; 30 ° < PM <60 °. Furthermore, the selectable regions of the system open loop cut-off frequency f c and the inductor current feedback coefficient H i are specifically the regions enclosed by the several constraint curves H i_GM1、Hi_GM2、Hi_PM and f c_Tfo.
In step S107, a suitable system open loop cut-off frequency f c and an inductor current feedback coefficient H i are selected from the selectable region, and a controller resonance coefficient K rv is calculated. When a proper system open loop cut-off frequency f c is selected, in order to inhibit higher harmonics, f c generally needs an equivalent switching frequency f sw lower than 1/10; when selecting a suitable inductance current feedback coefficient H i, in order to improve the dynamic performance of the system, a smaller H i is generally selected on the premise of ensuring a sufficient amplitude margin GM. In addition, the calculation formula of the controller resonance coefficient K rv is:
Where f c is the system open loop cut-off frequency.
Step S108, drawing a system gain baud chart according to the system open loop cut-off frequency f c and the inductance current feedback coefficient H i selected in the step S107, and checking whether the loop gain meets all design requirements. If the design requirement is met, outputting the parameter selection results of the open loop cut-off frequency f c, the inductance current feedback coefficient H i and the controller resonance coefficient K rv; if the design requirement is not satisfied, the process returns to step S107 to reselect the open loop cut-off frequency f c and the inductor current feedback coefficient H i.
Finally, a demonstration of design examples and simulation verification was performed under the circuit parameters given in table 1.
Table 1 simulation circuit parameters
By calculating the resonant frequency according to the parameters in the present design exampleDesign time requires GM 1>3dB,GM2<-3dB,PM>45°,Tfo >40dB.
The optional areas of f c and H i that can be drawn according to the constraint expressions of H i_GM1、Hi_GM2、Hi_PM and f c_Tfo obtained in step S104 and step S105 are shown in fig. 4, which is a schematic diagram of the optional areas of the open loop cut-off frequency f c and the inductor current feedback coefficient H i of the system under each constraint condition in the design example, and the optional areas are shown in the shaded portion in fig. 4. According to the closed-loop parameter design step and combining the areas shown in fig. 4, f c=400Hz,Hi =10 is selected, and the corresponding K rv =2513 is calculated.
Further, a system loop gain baud is plotted according to the selected closed-loop parameters, and fig. 5 is a system loop gain baud in a design example. As shown in fig. 5. Since H i =10 selected in this design example satisfiesThe number of the pole points of the right half plane of the open loop of the system is P=0, and the phase-frequency curve of the gain of the loop of the open loop of the system only passes through-180 degrees at f r, so that the GM 1 only needs to be verified to meet the requirement when the amplitude margin is checked. According to the baud diagram, the loop gain GM 1=5.97dB,PM=54.80°,Tfo = 52.04dB of the system can be calculated, and the design requirement is met.
In order to verify the correctness of the analysis and the rationality of the closed-loop parameter design, a simulation model of the three-phase networking grid-connected inverter is built based on a PLECS simulation platform. Fig. 6 is a simulation waveform of the inverter in each state in the design example. Wherein (a) in fig. 6 is a full-load steady-state operation waveform in the grid-connected mode, (b) in fig. 6 is an operation waveform when the reference voltage amplitude is reduced by 0.5p.u. in the off-grid mode, and (c) in fig. 6 is a load half-full-load jump waveform in the off-grid mode. FIG. 6 shows that the system has good steady state and dynamic performance while effectively damping the LC filter resonance peak by the parameter design method provided by the invention.
The method for designing the voltage loop control parameters of the grid-built inverter can be applied to computer equipment, computer storage media and the like, assists a designer in parameter selection, removes a trial-and-error process in the parameter design of the grid-built inverter, and is beneficial to analyzing the system performance and optimizing the closed loop control parameters, so that the system has ideal steady-state and dynamic performance while effectively damping the resonance peak of an LC filter.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (7)
1. The method for designing the control parameters of the voltage loop of the grid-formed inverter is characterized by comprising the following steps of:
Step S101, establishing a net-structured inverter mathematical model based on an inductance current proportional feedback active damping and voltage resonance regulator;
step S102, judging the magnitude relation between the resonant frequency f r and the sampling frequency f s which is 1/6 times of the resonant frequency f;
Step S103, respectively aiming at two cases of f r＜fs/6 and f r≥fs/6, determining the corresponding relation between the number P of the open-loop right half plane poles of the system and an inductance current feedback coefficient H i,
When f r＜fs/6, if the inductor current feedback coefficient H i satisfies:
Wherein, L f is the inductance value of the filter, f s is the sampling frequency, f r is the resonant frequency, the number of poles P of the right half plane of the system open loop is 0,
If the inductance current feedback coefficient H i satisfies:
the number P of the open loop right half plane poles of the system is 2;
When f r≥fs/6, for any inductance current feedback coefficient H i >0, the number P of the open loop right half plane pole points of the system is 2;
Step S104, based on the number P of the open-loop right half-plane poles of the system and combining with the Nyquist stability criterion, deriving a constraint expression of the amplitude margin GM and the phase angle margin PM on the voltage loop control parameters of the grid-connected inverter,
When f r＜fs/6, and the number of system open-loop right half-plane poles p=0, the magnitude margin GM 1 of the open-loop gain at f r is required to be > 0dB,
When f r＜fs/6 and the number of the pole points of the right half plane of the open loop of the system is P=2, the amplitude margin GM 1 of the open loop gain at f r is more than 0dB, the amplitude margin GM 2 of the open loop gain at f s/6 is less than 0dB,
When f r≥fs/6, the number of the pole points of the open-loop right half plane of the system is P=2, the amplitude margin GM 1 of the open-loop gain at f r is required to be smaller than 0dB, the amplitude margin GM 2 of the open-loop gain at f s/6 is required to be larger than 0dB,
The constraint expression of the amplitude margin GM 1、GM2 on the inductor current feedback coefficient H i_GM1、Hi_GM2 is:
Wherein GM 1 is the amplitude margin of the open loop gain at f r, GM 2 is the amplitude margin of the open loop gain at f s/6, L f is the filter inductance value, f c is the system open loop cut-off frequency, f s is the sampling frequency, f r is the resonant frequency,
The constraint expression of the phase angle margin PM of the open loop gain at the system open loop cut-off frequency f c on the inductor current feedback coefficient H i_PM is:
Wherein PM is the phase angle margin of the open loop gain at f c, f c is the open loop cut-off frequency of the system, T s is the sampling period, L f is the filter inductance value, and C f is the filter capacitance value;
step 105, deducing a constraint expression of fundamental wave gain amplitude T fo of the system on the control parameters of the voltage loop of the grid-connected inverter according to the steady-state error requirement of the system,
The constraint expression of the fundamental gain amplitude T fo on the system open loop cut-off frequency f c_Tfo is:
Wherein T fo is fundamental wave gain amplitude, f o is fundamental wave frequency, and ζ is damping ratio of the controller;
Step S106, according to the constraint expression of the voltage loop control parameters of the grid-formed inverter, setting a desired amplitude margin GM, a phase angle margin PM and a fundamental wave gain amplitude T fo, and drawing selectable areas of a system open loop cut-off frequency f c and an inductance current feedback coefficient H i;
Step S107, selecting a proper system open loop cut-off frequency f c and an inductance current feedback coefficient H i from the optional area, and calculating to obtain a controller resonance coefficient K rv;
Step S108, drawing a system gain baud chart according to the system open loop cut-off frequency f c and the inductance current feedback coefficient H i selected in the step S107, and checking whether the loop gain meets the design requirement.
2. The method of claim 1, wherein the voltage resonance regulator is an R controller.
3. The method according to claim 1, wherein in the step S106, the selectable areas of the system open loop cut-off frequency f c and the inductor current feedback coefficient H i are the areas surrounded by the constraint curves H i_GM1、Hi_GM2、Hi_PM and f c_Tfo.
4. The method according to claim 3, wherein in the step S107, the selected system open loop cut-off frequency f c is lower than the equivalent switching frequency f sw of 1/10; the calculation formula of the controller resonance coefficient K rv is:
Where f c is the system open loop cut-off frequency.
5. The method according to claim 1, wherein in the step S108, when the loop gain meets the design requirement, the parameter selection results of the open loop cut-off frequency f c, the inductor current feedback coefficient H i and the controller resonance coefficient K rv are output; when the loop gain does not meet the design requirement, the step S107 is returned to reselect the open loop cut-off frequency f c and the inductor current feedback coefficient H i.
6. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the method of grid-tied inverter voltage loop control parameter design of any one of claims 1-5 when the computer program is executed by the processor.
7. A computer storage medium having a computer program stored thereon, which when executed by a processor implements the method of designing a voltage loop control parameter of a grid-built inverter as claimed in any one of claims 1 to 5.
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| CN112564499A (en) * | 2020-12-04 | 2021-03-26 | 河海大学 | Method for designing parameters of high-voltage side inverter of modular multilevel DC transformer |
| CN113629984A (en) * | 2021-07-27 | 2021-11-09 | 浙江大学 | Three-phase LCL type SAPF parameter design method based on double-loop current control strategy |
| CN115632401A (en) * | 2022-12-21 | 2023-01-20 | 浙江大学 | SAPF parameter design method considering load and power grid impedance influence |
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| CN112564499A (en) * | 2020-12-04 | 2021-03-26 | 河海大学 | Method for designing parameters of high-voltage side inverter of modular multilevel DC transformer |
| CN113629984A (en) * | 2021-07-27 | 2021-11-09 | 浙江大学 | Three-phase LCL type SAPF parameter design method based on double-loop current control strategy |
| CN115632401A (en) * | 2022-12-21 | 2023-01-20 | 浙江大学 | SAPF parameter design method considering load and power grid impedance influence |
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