Wind power plant sub-synchronous resonance suppression method based on parallel voltage source current converter

Abstract

The invention discloses a wind power plant sub-synchronous resonance suppression method based on a parallel voltage source current converter, and belongs to the technical field of the stability analysis and control of the power system. The method comprises the following steps: measuring current on a wind power cluster convergence line to obtain connecting line current; designing a low-pass filterand a band rejector filter to filter the connecting line current so as to obtain the connecting line sub-synchronous current; designing phase compensation and proportion gain loop so as to obtain sub-synchronous damping current, wherein a voltage outer ring enables the device DC voltage to track a reference value under the effect of a PI regulator, and an output value is converted through a phaseangle so as to obtain DC voltage compensation current; adding the DC voltage compensation current and the sub-synchronous damping current to obtain an output current reference value, wherein a currentinner ring enables the SSO-DS output current to track the output current reference value under the effect of the PI regulator, the current is injected into the wind power cluster system to provide positive damping for the system, thereby achieving the effect of depressing the sub-synchronous resonance. The method disclosed by the invention has important significance for depressing the sub-synchronous resonance problem caused by the wind power integration in a centralized way.

Description

technical field [0001] The invention belongs to the technical field of power system stability analysis and control, and in particular relates to a subsynchronous resonance suppression method of a wind farm based on a parallel voltage source converter. Background technique [0002] The large-scale construction and grid-connected operation of wind power put forward higher requirements for solving the problem of its consumption. Due to the regional characteristics of wind energy, the overall distribution of wind energy resources and load centers in my country is reversed. Large-scale, high-voltage, and long-distance transmission of wind power is essential. Series capacitor compensation and high-voltage direct current transmission are one of the economical and effective measures to solve the long-distance transmission of electric power, and they are also one of the main measures for wind power grid-connected long-distance transmission at present. The subsynchronous resonance pro...

AI Technical Summary

Problems solved by technology

In October 2009, a sub-synchronous resonance accident with a frequency of about 20 Hz occurred between the doubly-fed wind turbine group and the series-compensated power grid in a wind farm in Texas, USA, causing damage to the crowbar circuit of a large number of wind turbines and disconnection

Therefore, the traditional subsynchronous resonance suppression method for thermal power is no longer applicable, and there is an urgent need to develop subsynchronous resonance suppression measures suitable for engineering wind power grid connection

Images