Inverter control method based on fuzzy pci and pr parallel compound control

Abstract

The invention relates to an inverter control method based on fuzzy PCI (Proportional Complex Integral) and PR (Proportional Resonance) parallel composite control. The inverter control method comprises the steps of S1, acquiring a current three-phase grid-connected current under a three-phase static coordinate system in real time; S2, acquiring a grid-connected current instruction under the three-phase static coordinate system to obtain an AC error signal under the three-phase static coordinate system; S3, acquiring a first current value under the three-phase static coordinate system after the AC error signal passes through a PR controller; S4, acquiring a second current value under the three-phase static coordinate system after the AC error signal passes through a PCI controller; and S5, acquiring a composite control current value under the three-phase static coordinate system after the first current value is added to the second current value, and inputting the composite control current value to a PWM (Pulse Width Modulation) module. Compared with the prior art, the inverter control method has the advantages that a coordinate conversion link can be omitted, the inverter control method can be directly applied to the three-phase static abc coordinate system, the control stability of a system is ensured, and the waveform quality, the tracking precision and the power factor of the grid-connected current are improved.

Description

technical field [0001] The present invention relates to the field of inverter control, in particular to an inverter control method based on fuzzy PCI and PR parallel compound control, in particular to an LC type three-phase grid-connected inverter based on fuzzy PCI and PR parallel compound control A single-loop control method for transformers. Background technique [0002] In recent years, with the increasingly tense energy supply in the world today, people have paid more and more attention to the development and utilization of a series of renewable energy sources such as wind energy and solar energy. The grid-connected inverter is the main interface connecting the distributed power supply and the grid, and its control performance is very important. Generally, the grid-connected inverter must be able to realize the same frequency and phase of the output current and the grid voltage on the one hand, and on the other hand must be able to realize the output sinusoidal current...

AI Technical Summary

Problems solved by technology

Each control method has its own advantages and disadvantages. Among them, PI control has the advantages of simplicity, fast dynamic response and strong robustness, but it has AC steady-state errors when controlling AC volume; PCI control extends the traditional PI to the complex domain, which can Effectively eliminate the AC steady-state error of grid-connected current control; the amplitude-frequency characteristics of PR control tend to be infinite at the resonant frequency, which can achieve zero steady-state error of AC volume, and at the same time have good performance against grid voltage interference; repetitive control is based on basic Wave cycle correction error signal, the corresponding steady-state performance is good, but the transient performance is poor; the object of fuzzy control does not need to be very precise, mainly suitable for complex nonlinear systems

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