新颖的双馈式风力发电机低电压穿越控制策略

Novel Control Strategy for Low Voltage Ride-through of Doubly-fed Wind Power Generator

针对现有文献中双馈风力发电机组低电压穿越控制策略存在的缺陷,提出一种新颖的低电压穿越控制策略.在电网故障期间,利用双滞环电流控制器快速的瞬态响应速度和对系统参数变化的不敏感性来抑制转子电路的过电流;在dc-link上采用crowbar技术,吸收转子侧多余能量,防止直流母线电压过高.在Mtalab/Simu1ink平台中构建了所提出的低电压穿越控制策略的动态仿真模型,研究了三种典型电网故障下的低电压穿越性能,验证了所提出的低电压穿越策略的可行性.仿真结果表明所提出的低电压穿越策略抑制了转子绕组的过电流和dc-link的电容过电压,改善了双馈式风力发电机的低电压穿越性能.

Aiming at the defects of LVRT control strategies of doubly-fed wind power generator in the cur-rent literatures,a novel LVRT control strategy is proposed.During the grid fault,the rotor overcurrent is suppressed by using the DHCC which has the fast transient response speed and the insensitivity to param-eter variations.And the dc-link voltage is restrained by means of the crowbar technology which absorbs the excess energy and protects the overvoltage of dc-link bus.The dynamic simulation model based on the proposed LVRT control strategy is structured in Mtalab / Simu1ink platform. The LVRT performances of doubly-fed wind power generator under three kinds of typical grid fault are investigated,and the feasibili-ty of the proposed LVRT control strategy is verified.The simulation results show that the proposed LVRT control strategy suppresses the overcurrent of rotor windings and the capacitor overvoltage of dc-link.So, the proposed control strategy improves the LVRT performance of doubly-fed wind power generator.