分段初级永磁直线同步电机提升系统失电保护分析

采用有限元法结合运动系统的能量解析式对分段初级永磁直线同步电机（PMLSM）垂直提升系统的失电保护过程的几个阶段进行分析，其实质是PMLSM三相绕组短路时的发电制动过程.上升过程中失电，制动过程可分为3个阶段：减速上行、加速下行、匀速下行.在这3个阶段中，流过电机绕组的电流和动子速度变化很大，变化程度由负载大小、绕组阻抗及动子永磁体产生的磁场强度等决定.电流和速度的仿真和试验结果验证了失电保护过程分析的正确性.

Analysis of power fail interrupts protection duration of vertical lift driven by discontinuous primary PMLSM

Duration of power fail interrupt protection of discontinuous primary Permanent Magnet Linear Synchronous Motor(PMLSM) was analyzed using finite element method(FEM) combining energy analytical formulation of the motion system.The study was focus on power generation braking for three-phase short-circuit of PMLSM.If the power fails interrupt in the motor mover upward process,braking duration may include three phases: decelerate up,accelerate down,speed-constant.In the duration,the motor current and the mover velocity changed rapidly,extents changing were depended on load magnitude,winding resistance and magnet density reduced permanent magnet etc.The analysis for power fail interrupt duration was validated by the compares of simulation and experiment results of the current and velocity.