本文结合矩阵变换器、双馈感应电机(DFIG)风力发电系统的优点,导出了双馈电机风力发电系统在同步旋转dq坐标轴下的矢量控制数学模型;针对常规矢量控制中存在电流耦合情况,设计一种新型、简易的电流前馈解耦控制方案。在此基础上,建立基于矩阵变换器交流励磁磁场定向电流解耦矢量控制策略。MATLAB仿真结果表明,当有功、无功功率变化时,电流解耦控制具有良好动态性能。本文设计了11kW风力发电试验装置并进行离、并网实验,当双馈电机处于亚同步、超同步状态时,双馈电机定子电压和频率均能保持稳定,实现变速恒频运行。实验结果表明,基于矩阵变换器交流励磁双馈风力发电系统是可行的,并具有一定的实用价值。
Matrix converter has the advantages of simple structure, power factor controllable, energy twoway flow and so on. In this paper, combined with the characteristic of matrix converter and the ACexited Double FedInduction Generator technology of VariableSpeed Constant Frequency (VSCF) , the DFIG's vector control mathe matical model in dq synchronous rotating frame was deduced. Considering the current coupling, this paper proposes a new type simple current feed forward decoupling control algorithm. Based on the principle, Matlab simulation re suits show that the current decoupling algorithm has superior dynamic performance when the active and reactive power are changing. Experimental device of 11 kW DFIG wind power generator system was constructed. Both in the supersynchronous and subsynchronous state, the stator voltage and frequency can remain stable. The results verify the feasibility of the control strategy, which has a certain practical value.