永磁同步电机数字控制延时模型及影响分析

Analysis of Digital Control Time Delay Model and Influence in Permanent Magnetic Synchronous Motor System

在数字控制系统中,影响系统性能的主要因素包括A/D采样频率、计算频率、开关频率。由于在大功率逆变器中受到开关损耗的限制,器件开关频率较低,相当于系统中有很大的延时惯性环节。文章首先介绍数字控制系统延时产生的原因,然后在同步坐标系下建立表贴式永磁同步电机数学模型,分析延时对系统稳定性的影响。最后,在20kW永磁同步电机试验台架上验证了延时对控制系统的影响。

In digital control system,there are several factors affect the system’s performance including the A/D sampling frequency,calculating frequency and the switching frequency.Limited by switching losses in the high-power inverter,the switching devices work at low frequency.It’s equivalent to a large delay in system.Firstly,this paper analyzes the cause of time delay.And then the surface permanent magnet synchronous Motor(SPMSM)model in synchronous frame is established.Secondly,the system stability ability is analyzed.Finally,the time delay’s influence is verified in 20 kW SPMSM experiment platform.