Robust and sensorless control of linear switched reluctance motors

Linear Switched Reluctance Motor (LSRM) is an attractive candidate for high-speed and high-precision position applications due to its low cost, simple and robust structure, ruggedness and reliability in harsh environments. On the other hand, the main limitations of LSRM come from the nonlinearity of magnetic circuit, the force ripples and the requirement of position sensors.;The ultimate objective of this project is to investigate and propose an effective robust controller and a novel sensorless control scheme for a high-performance LSRM. In this way, the expensive position sensor can be eliminated and the LSRM can enlarge its scope of applications with the overall cost reduced.;To achieve this target, the measurement of magnetic characteristics of the motor is firstly carried out at the initial research stage. Furthermore, a full-order system model and a reduced-order system model are proposed and verified.;At the second research stage, two robust controllers are designed for the drive system. With the reduced-order model, a Self-Tuning Regulator (STR) is developed for high precision position control. Afterwards, a Passivity-Based Controller (PBC) is designed for both the full-order model and the reduced-order model. Simulations and experimental results demonstrate that the controllers of the LSRM drive system can achieve a high-precision position tracking with insensitivity to system uncertainties and external disturbances.;At the final research stage, a continuous position estimation scheme is presented for LSRMs. The scheme uses diagnostic current injection into an unenergized phase to detect the motor position. On the basis of the estimation, a system design of sensorless position control for LSRMs is proposed. The effectiveness and feasibility of the scheme are confirmed by the hardware implementation of the sensorless position control system on the LSRM.