低载波比永磁同步发电机PWM整流的改进拓扑

摘要

Permanent magnet synchronous generator can be processed with a PWM rectifier and vector control for rectifying and DC voltage stabilization.In high speed or large power PMSG systems,the carri-er ratio which is the ratio between the rectifier switching frequency and the PMSG fundamental frequency is low,thus the vector control performance is deteriorated.Therefore,improved PWM rectifier topology is proposed.By increasing the equivalent switching frequency of the rectifier while keeping the device switc-hing frequency unchanged,the vector control worked better.Mathematical model of the PMSG-PWM rec-tifier system was established, the vector control strategy was employed.A unique generation method of the PWM signals corresponding to the improved topology was proposed.Simulation and experiment are carried out,verifying the improved topology and the unique vector control methodology.%永磁同步发电机可以使用PWM整流器进行整流与直流稳压,并采用SVPWM矢量控制策略.在诸如高速发电机及大容量发电机系统中,PWM整流器的载波比(开关频率与基波频率比值)低,以致矢量控制性能恶化.为此,提出PWM整流器改进拓扑,在维持功率管开关频率不变的前提下提高整流器的等效开关频率,改善矢量控制的品质.根据PMSG和PWM整流器在d-q坐标系下的数学模型,构建矢量控制系统,提出针对改进整流器的PWM信号生成方法,并进行仿真和实验研究.仿真和实验结果均验证PWM整流器改进拓扑的有效性及PMSG系统矢量控制算法的正确性.