Crowbar优化控制策略下的双馈风机无功调节能力研究

在分析双馈风机(DFIG)无功调节原理的基础上,根据最新的低电压穿越要求,建立优化的Crowbar控制策略,进而提出在电网严重故障期间内,Crowbar投入时由网侧变流器充当STATCOM为电网提供无功,Crowbar退出时无功输出继续由转子侧变流器励磁调节控制,推导出DFIG网侧及定子输出无功功率极限的表达式,结合优化的Crowbar控制策略研究DFIG的无功调节能力,最后利用RTDS平台进行仿真验证。结果表明,DFIG的无功调节能力与理论分析一致,在电网故障期间,应用此控制策略的DFIG可连续提供最大无功支持,且能帮助恢复电网电压。

Research on Reactive Power Regulation of Double-fed Induction Generator under Crowbar Optimization Control Strategy

Based on the analysis of the principle of reactive power regulation of doubly-fed induction generator (DFIG), an optimal Crowbar control strategy was established in terms of the latest low-voltage traversing requirements. During the serious failure period of the grid, the grid side converter as STATCOM was propose to provide reactive power when Crowbar was put into operation. While Crowbar was cut, reactive power output was continuous to be controlled by the converter excitation regulation in rotor side. The expression of reactive power limit grid side and stator output was deduced, and the reactive power regulation capability of DFIG was studied by combining the optimal Crowbar control strategy. Finally, RTDS platform was used for simulation verification. The results show that the reactive power of DFIG is consistent with the theoretical analysis. During the grid failure, DFIG with the proposed control strategy can continuously provide maximum reactive power support to help the grid voltage recovery.