不同PWM模式下交流电机单电阻三相电流采样的研究  

Research on phase current reconstruction for AC motor based on different PWM mode

作　　者：王帆[1] 陈阳生[1] 

机构地区：[1]浙江大学电气工程学院,浙江杭州310027

出　　处：《机电工程》2013年第5期585-590,631,共7页Journal of Mechanical & Electrical Engineering

摘　　要：为解决交流电机相电流采样的问题,将母线单电阻采样三相电流重构技术应用到交流电机系统中。对母线单电阻采样三相电流重构技术的原理进行了研究,定义了由低压调制区与扇区过渡区构成的非观测区的概念。开展了对母线单电阻采样三相电流重构技术在SVPWM与BCPWM两种PWM调制方式下非观测区问题的分析,建立了PWM移相时间与最小采样时间的关系,提出了使用PWM非对称输出方式解决母线单电阻采样三相电流重构技术非观测区问题的方法。在BCPWM与SVPWM两种调制模式下,对PWM移相输出的各种状态波形进行了分析,最后,进行了永磁同步电机全区域母线采样三相电流重构试验。研究结果表明:该母线采样三相电流重构技术在两种PWM调制方式下都具备可行性和使用价值。Aiming at phase current sampling of AC motors,the three-phase current reconstruction for AC motor drives using a DC-link single current sensor was investigated.After the research of principle of this method,the definition of unobserved region composed by low-voltage modulation region and transition region was proposed.After the analysis of unobserved region of three-phase current of this method based on SVPWM and BCPWM,the relationship of PWM shift time and minimum sampling time was established.A method was presented to solve the problem of unobserved region by using asymmetric PWM output.After the analysis of status and waveform of PWM shifting output based on both SVPWM and BCPWM,the method of three-phase current reconstruction using DC bus current of PMSM on whole region was tested.The results indicate that the three-phase current reconstruction has feasibility and practical value on both SVPWM and BCPWM.

关 键 词：交流电机 单电阻采样 电流重构 BCPWM 非对称PWM输出 

分 类 号：TM34[电气工程—电机] TP24[自动化与计算机技术—检测技术与自动化装置]