Abstract:
The armature windings and permanent magnets of the modular liner flux-switching permanent magnet machines (LFSPM) are placed in the primary short mover, while the secondary long stator is composed only of the conductive magnet core, which is suitable for elevators, etc. in long distance rail transport system. In the elevator drive system, the main operation is electric operation when going up, and it is often in power generation or even braking operation under the action of self-weight when going down. The alternating change of operation mode brings challenges to the position sensorless control. Therefore, based on the mathematical model of the
d-q axis of the LFSPM motor, a position sensorless control system based on the model reference adaptive system (MRAS) of the LFSPM motor is established. A hybrid control strategy is designed based on operating conditions. When the elevator is going up, it adopts control with
id=0. When the elevator is going down, it is in the state of light load braking power generation, the proportion of the fundamental wave in the voltage and current signal is small, so that flux-strengthening control is carried out. The
id is used to adjust the proportion of the fundamental wave in the voltage and current signal to meet the requirements of speed identification. The reasons for the large error in the angle position estimation of the sensorless control system are analyzed, and a current-based compensation method is proposed. The prototype experiment results prove the effectiveness of the proposed hybrid control strategy.