基于滑模观测器的永磁直驱风电机组位置自检测控制

摘要

In order to eliminate the position sensor and to develop a reliable rotor position self-sensing technology, a position self-sensing control method based on sliding mode observer for the MW permanent magnet synchronous generator wind turbine system was proposed. In the control strategy, because the back electromotive force of the generator stator contains the position and speed information of the rotor, so design sliding surface and sliding mode observer based on the ideal state trajectory of the estimated stator currents and the actual stator currents. Then, design the converter generator side and grid side control algorithm according to the control goal of wind turbine. In addition, the three-level neutral point clamped back-to-back full-scale power converter has been chosen as the control object , and the three-level space vector modulation algorithm has been used to reduce the total harmonic content of the output voltage. Finally, a simulation model of the wind turbine based on MATLAB/Simulink has been built, and some calculations have been done. The simulation results showed that the wind turbine realized maximum power point tracking and electric feed function with the sliding mode observer based position self-sensing control and grid-side decoupling control. So, the feasibility of the proposed control scheme has been proved.%以消除位置传感器和开发可靠的转子位置自检测技术为目标，提出了一种基于滑模观测器的兆瓦级永磁直驱风力发电机组位置自检测方案。该控制策略中，首先根据发电机定子反电势中蕴藏转子的位置和速度信息的原理，以估算定子电流与实际电流的理想状态轨迹设计了滑模面及滑模观测器，然后根据风电机组的控制目标设计了变流器的机侧和网侧控制算法。此外，控制对象选为三电平中点钳位型背靠背全功率变流器，并采用三电平空间矢量调制算法，以减小输出总谐波含量。最后，基于MATLAB/Simulink仿真平台搭建了风电机组的仿真计算模型，并进行了仿真计算。计算结果表明，在基于滑模观测器的转子位置自检测控制和变流器网侧解耦控制作用下，风电机组实现了最大功率点跟踪和电能馈送功能，验证了所提出控制方案的有效性。