负序及谐波畸变电网电压下双馈风力发电系统的改进直接功率控制策略  

Improved Direct Power Control Strategy of DFIG System under Unbalanced and Distorted Grid Voltage

作　　者：周波 宋亦鹏[2] 年珩[2] 程晨闻 

机构地区：[1]国网四川电科院,成都610072 [2]浙江大学电气工程学院,杭州310027

出　　处：《电工技术学报》2017年第24期233-243,共11页Transactions of China Electrotechnical Society

摘　　要：由于定子直接连接到电网,电网电压中的负序和谐波分量会严重恶化双馈风力发电机(DFIG)系统的运行性能,导致系统输出总电流三相不对称及谐波畸变、总输出有功功率及无功功率波动等,使得DFIG系统无法安全稳定可靠运行,且输出风电质量下降。同时考虑负序和谐波电网下DFIG系统机侧变流器和网侧变流器的运行状态,以改善DFIG系统总输出电流或功率质量为目标,研究基于二阶矢量积分器(SOVI)的DFIG系统网侧和机侧变流器改进直接功率控制(DPC)策略,改善DFIG系统的运行性能。实验结果验证了所提出的负序和谐波畸变电网电压下DPC策略的正确性及有效性。As the stator windings are directly connected to the power grid, the unbalanced and harmonic components （mainly 5th and 7th harmonics） in grid voltage can severely deteriorate the operation performance of doubly fed induction generator （DFIG） system. As a result, current imbalance, harmonic distortion, pulsated active and reactive powers, and fluctuated electromagnetic torque will be generated. It causes damages to the DFIG system and jeopardizes the wind power qualities. Therefore, this paper proposes an improved direct power control （DPC） strategy for the rotor side converter and grid side converter, where the current or power quality of total DFIG system is improved by constructing additional second order vector integral closed loop for them. The proposed strategy has been validated with experiments on a DFIG rig.

关 键 词：负序和谐波畸变电网电压 双馈异步发电机 机侧变流器 网侧变流器 直接功率控制 二阶矢量积分器 

分 类 号：TM614[电气工程—电力系统及自动化]