Discrete-time current controller for induction motors at low switching frequency

作者：Zhao Leiting^*; Diao Lijun; Zhang Zhe; Liu Zhigang

来源：Proceedings of the CSEE, 2014, 34(21): 3456-3466.

DOI：10.13334/j.0258-8013.pcsee.2014.21.008

• Current controller
• Digital control delays
• Low switching frequency
• Zero-pole cancellations

Discrete-time current controller plays an important role in vector control of induction motors, which affects the decoupling effect of motor torque and flux, output torque response and even the stability of converter-motor system. However, in high power AC drive system, the traction converter often operates at low switching frequency to reduce the dynamic losses of the power devices, which leads to large digital control delay, enhancing the induction motor dq axis current cross coupling. In order to overcome the problem, this paper provided a comprehensive analysis of the induction motor coupling factors. Then using the principle of zero-pole cancellation, an improved discrete current controller was proposed, which not only ensures excellent dynamic performance but also cancels cross coupling between the torque component and flux component of stator current in the discrete-time domain. The results of model simulation and experiment prove the validity and feasibility of improved discrete current controller.

• 出版日期2014
• 单位北京交通大学