Control system for low voltage ride through of doubly-fed wind generator

Abstract

The invention discloses a control system for low voltage ride through of a doubly-fed wind generator. A doubly-fed wind generator-side converter is formed by assembling a core circuit, a sampling circuit and a main circuit, wherein the core circuit takes a digital signal processor (DSP) as a controller; the sampling circuit is formed by analog acquisition conversion; and the main circuit is formed by an intelligent power module (IPM) intelligent switch modular circuit. According to the control system for the low voltage ride through of the doubly-fed wind generator, disclosed by the invention, by aiming at the problem that the doubly-fed wind generator-side converter is excessive in current due to the depth of network voltage drop and the running status of the doubly-fed wind generator when the voltage drops, rotor-side overcurrent is restrained by adopting the virtual impedance technology so as to prevent a bar protection circuit from being triggered, so that the doubly-fed wind generator still is in a controllable state under the condition of network faults, and therefore, the doubly-fed wind generator meets the fan-class grid-connection national standard.

Description

technical field [0001] The invention relates to the interdisciplinary technical field of new energy utilization and control, electric engineering, and power electronics, and in particular relates to a low-voltage ride-through control system for a doubly-fed wind power generator. Background technique [0002] At present, energy consumption is increasing rapidly around the world, and the consumption of fossil fuel energy will still occupy a dominant position, which will cause many problems such as environment, health, economy and energy security. Over the past 20 years, renewable energy technologies have achieved great breakthroughs in reliability and performance while successfully reducing costs. Among them, wind energy, as a renewable, non-polluting and clean energy, has been paid more and more attention by human beings. [0003] Doubly-fed induction motor has become a research focus and development direction because of its unique technical advantages such as high utilizati...

AI Technical Summary

Problems solved by technology

When the skid rod circuit is put into operation, the double-fed motor actually runs in the state of the cage motor, which absorbs reactive power from the grid, which increases the difficulty of grid recovery and increases the cost of the system; the new topology needs to improve the system The principle structure, but the cost of transformation is relatively high; the operability of the improved excitation control algorithm is relatively poor

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