基于RTDS的双馈式风电机组低电压穿越策略

IMPROVE LVRT STRATEGY FOR DFIG WIND POWER GENERATION SYETEM BASED ON RTDS

在研究2 MW双馈式风力发电系统稳态和暂态数学模型、控制策略、低电压穿越Crowbar电路参数优选等理论的基础上,利用RTDS平台建立双馈式风力发电低电压穿越系统完备模型,定量模拟电网电压跌落,发现传统的Crowbar保护方案仍有一定改进空间,提出改变Crowbar电路投切时刻提升系统LVRT能力策略,从多角度验证深度电压故障跌落时双馈电机低电压穿越性能。研究结果表明,在严重的电网电压跌落情况下,所采用的研究方案可在保证双馈风力发电机组变换器装置自身安全的基础上,实现机组的不脱网运行,满足国网的风电低电压穿越运行要求。

Based on the studies on the steady state and transient state mathematical model and control strategy of 2MW double-fed wind power generation system and the theory of Crowbar circuit parameters optimization, develop a complete model of the doublefed wind power generation LVRT system use RTDS platform. Contrastive study is done between the traditional LVRT method and improved LVRT method which input and exit Crowbar protection circuit. A novel improve LVRT of DFIG wind turbine by change time of switch Crowbar circuit is proposed. The research test and verify the performance of doubly-fed wind power system under serious sag of power system voltage from different point of view. The results show that the improved scheme better on the recovery of system voltage. It can ensure the security of the converters of the double-fed wind power generation, and can realize uninterrupted operation of the DFIG and meet the LVRT requirements of the State Grid.