不平衡电压下双笼转子无刷双馈发电机的多目标控制

Multi-objective Control of Dual-cage-rotor Brushless Doubly Fed Induction Generator Under Unbalanced Grid Voltage

该文以双笼转子无刷双馈感应发电机为主要研究对象。为了解决不平衡电网电压带来的功率绕组(power winding,PW)定子绕组功率脉动和电流不平衡的问题,设计了简化矢量控制策略,对PW侧谐波功率和负序电流进行抑制。此外,通过建立控制绕组(control winding,CW)电流统一表达式,对各个控制目标之间的关系进行了数学推导和理论分析。在此基础上,建立了PW电流不平衡度约束条件下,针对PW有功功率脉动幅值和无功功率脉动幅值的多目标控制数学模型。并采用粒子群算法进行求解,对CW统一电流表达式中的系数进行优化,计算CW参考电流值从而实现多目标控制。最后在双笼转子无刷双馈感应发电机实验平台上,对所提出的控制策略的有效性和理论推导的正确性进行了验证。

This paper focuses on a dual-cage-rotor brushless doubly fed induction generator(DCR-BDFIG).In order to suppress the power oscillations and imbalanced current of power winding(PW)caused by unbalanced grid voltage,a simplified vector control strategy based on single current loop is proposed,which can realize one of three selectable control targets including suppressing the PW active power oscillation,PW reactive power oscillation and PW imbalanced current.Then based on the presented unified control winding(CW)current expressions,relationships of three alternative control targets are analyzed.After that,by optimizing the coefficients in unified CW current expressions,the multi-objective control model of PW active and reactive power oscillation is established with restriction of the vector unbalanced degree(VUD)of PW current,and solved by particle swarm optimization(PSO)algorithm to calculate the reference CW currents.Finally,the effectiveness of the proposed control strategy,and the accuracy of theory derivation are validated by simulation and experiment.