FPGA-based sensorless controller for PMSM drives using sliding mode observer and phase locked loop

FPGA-realization of a rotor position estimation algorithm based on the novel sliding mode observer (SMO) and phase locked loop (PLL) for the permanent magnet synchronous motor (PMSM) drives is adopted in this paper. Comparing to the conventional SMO, the estimator based on the novel SMO and PLL is presented for reducing the chattering phenomenon and improving the estimated precision of the rotor position. However, a hybrid sensorless control system for PMSM drives using I-f startup method then a smooth transition to the novel SMO and PLL sensorless field oriented control (FOC) are also considered in this paper. In realization, a very high speed IC hardware description language (VHDL) is firstly introduced to describe the behavior of the adopted estimation and control algorithm which is called the sensorless control IP (Intellectual Property). Then, to verify the correctness of the designed VHDL code for the sensorless control IP, it will be downloaded to the FPGA, and an experimental system with a sensorless PMSM drive is set up and some experimental results are demonstrated.