PMSM三相短路暂态过程解析建模及主动短路功能实现

Analytical Modeling of PMSM Three-phase Short-circuit Transient Process and Realization of Active Short-circuit Function

为解决永磁电机高速弱磁运行时,因逆变器故障保护功能机制,导致逆变器进入不可控整流状态,从而导致永磁同步电机高速失控的问题,提出主动短路功能,用于电驱动永磁同步电机安全关断。基于永磁同步电机在dq0坐标系统中的派克方程,利用永磁同步电机三相短路时直、交轴电压为零的边界条件,采用矩阵运算和拉普拉斯变换的方法,求解出不同短路起始条件下永磁同步电机切入主动短路时的直、交轴电流和制动扭矩暂态输出特性。建立主动短路时电机暂态输出特性与电机本体参数、短路起始条件之间数学模型,并进行了模型验证。通过模型潜在应用场景分析,提出主动短路功能实施的注意事项及技术方案,为电驱动系统设计提供详细依据。

In order to solve the problem that the inverter enters the uncontrollable rectifier state due to the inverter fault protection function mechanism during the high-speed weak magnetic operation of permanent magnet synchronous motor, which leads to the high-speed out of control of permanent magnet synchronous motor, the active short-circuit function was proposed for the safe shutdown of electrically driven permanent magnet synchronous motor. Based on the Parker equation of permanent magnet synchronous motor in dq0 coordinate system, using the boundary condition that the DC and AC axis voltage of permanent magnet synchronous motor is zero in three-phase short circuit, the transient output characteristics of DC and AC axis current and braking torque when permanent magnet synchronous motor cuts into active short circuit under different short circuit starting conditions were solved by using matrix operation and Laplace transform. The mathematical model between the transient output characteristics of the motor during active short circuit and the parameters of the motor body and the starting condition of short circuit was established, and the model was verified. Through the analysis of potential application scenarios of the model, the precautions and technical scheme for the implementation of active short-circuit function were put forward, which provided a detailed basis for the design of electric drive system.