Sliding Mode Direct Force Control for Linear Drive System

Abstract

SummaryA linear motor is direct driven and it can achieve far better acceleration, velocity and position accuracy than its rotary rival motor. The simplest linear motor is the single-sided linear induction motor (LIM), which consists of a primary coil assembly and a secondary formed by a reaction plate.This paper proposes a relatively simple and robust control solution to mitigate the uncertainties of a single-sided linear induction motor. A sliding mode based direct force control (DFC) has been used in a linear drive system because of its fast and precise force response. A control method has been designed, implemented and tested on a test bed platform, where the DFC controls the thrust force of the linear motor by directly setting the primary voltages. The experimental results have proven that DFC with a sliding mode can achieve faster response and be more robust than the conventional vector control under the same conditions.