Real-time encoder faults detection and rotor position estimation for permanent magnet synchronous motor drives fault tolerant sensorless control using digital signal controller

As it is known, encoder is one of the most used devices in permanent magnet synchronous motor (PMSM) drives, especially when a closed loop operating is required. It gives important information for PMSMs vector control. However, this sensor is sensitive to many types of faults such as the total loss of the position information, the position disturbance by noises and the frequency variation of the position due to vibrations phenomena. In this paper, the first issue deals with real-time encoder faults detection using the discrete wavelet transform - based multiresolution analysis (DWT-MRA). Then, the second issue discusses the PMSM rotor position estimation using an efficient high frequency signal injection (HFSI) in order to ensure the PMSM fault tolerant sensorless control (FTSC). A digital signal controller (DSC) dsPIC30F6010A has been used for DWT-MRA and HFSI algorithms implementation.