永磁直驱风电系统发电机侧变流器的并联控制

Parallel Control of Generator-side Converters for Permanent Magnet Direct-drive Wind Power Generation Systems

针对永磁直驱风力发电系统中发电机多极对数、低速运行特性,提出易于实现、鲁棒性能好的滑模转子位置观测器,准确估计电机转子位置。在无位置传感器运行条件下,发电机转矩、磁链响应仍然保持良好的稳、动态性能;解决了安装光电编码器带来的可靠性和受干扰反馈错误位置信息等问题,提高了系统的可靠性。大功率直驱风力发电系统相对于双馈系统需要全功率变流器。目前,在MW级系统中电能变流器拓扑结构通常采用背靠背PWM变流器并联,用相同PWM脉冲触发和载波移相等两种控制方式。对两种方法的控制效果进行了实验验证,实验结果表明了机侧变流器的无位置传感器载波移相并联技术提高了系统的鲁棒性、可靠性,降低了噪声,能使系统发出优质电力。

We presents an easy-to-implement and robust Sliding Mode Observer（SMO） for rotor position sensing for a direct-drive wind power generation system.Without any position sensor,the generator torque and flux responses retain high performance both in the steady state and during transients.The problems on the shaft encoder installation difficulty,reliability and disturbance in encoder cable are remedied and the reliability of the PMSG generating system is increased.High power direct-drive wind power generation system needs full power converter compared to doubly fed induction generator.The parallel back-to-back PWM converters are used in megawatt-level high-power generation system.The generator-side converter and grid-side converter can be controlled separately.Two control strategies of the generator-side converters are compared.The test platform is designed and the experimental results prove the effectiveness of control strategy.