Feedforward control method, device and computer-readable storage medium of grid-connected inverter

Abstract

The present disclosure provides a feedforward control method, device, and computer-readable storage medium of a grid-connected inverter, the feed-forward control method comprising: capacitance from a capacitor in a filter connected to an output end of the grid-connected inverter The voltage extracts the harmonic signal in the first predetermined frequency range; determines the frequency corresponding to the maximum value of the harmonic amplitude based on the harmonic amplitude of each frequency of the harmonic signal in the first predetermined frequency range; The harmonic voltage component is obtained by band-pass filtering with frequency as the center frequency; the feedforward voltage control component is obtained based on the fundamental voltage component and harmonic voltage component of the capacitor voltage. The feedforward control method and feedforward control device for a grid-connected inverter according to the embodiments of the present invention can improve the suppression effect of the active damping strategy on resonance.

Description

technical field [0001] The present invention generally relates to the field of grid-connected inverters, and more particularly, to a feedforward control method, device and computer-readable storage medium of a grid-connected inverter. Background technique [0002] At present, the use of grid-side AC voltage for grid-side resonance suppression is a feasible solution. In order to reduce the impact on other frequency harmonics, band-pass filters are used to extract harmonics near the resonant frequency in the voltage. [0003] In actual operation, although the grid-side reactance and grid-side filter are fixed, the last inductance of the grid-side filter generally uses the leakage inductance of the box change, and its inductance value will change. In addition, considering that the lines of different wind farms are different, the strength of the power grid is also different. In the same wind farm, even if the wind turbines of the same model are connected to the power grid, the l...

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Problems solved by technology

[0003] In actual operation, although the grid-side reactance and grid-side filter are fixed, the last inductance of the grid-side filter generally uses the leakage inductance of the box transformer, and its inductance value will change

In addition, considering the different lines of different wind farms, the strength of the power grid is also different. In the same wind farm, even the same type of wind turbines, the connection grid lines are different. It affects the impedance of the line, so it will indirectly lead to the deviation of the actual converter's grid-side resonance point from the design value, that is, the resonance point is dynamically changed on the basis of the design value, which will affect the suppression of resonance by the active damping strategy adverse effect

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