Three-Phase Current Unbalance Suppression Method of Linear Induction Motor Based on PR Controller

The new generation electromagnetic launch microgravity experiment facility is driven by a long primary linear induction motor with segmented power supply, which can achieve mu g-level microgravity. The primary three-phase current of this kind of linear motor is obviously unbalanced, which will cause thrust ripple and increased mover loss. This paper adopts the method of parallel proportional resonance (PR) controller in current closed-loop to suppress the negative sequence component of unbalanced current and improve motor performance. This study carries out system co-simulation and experiment on 82 kW linear motor to prove that its suppression on unbalanced three-phase current is feasible.