Angle estimation using high frequency injection for sliding mode controlled permanent magnet synchronous machines drives

In this paper, high frequency injection (HF) technique for rotor position estimation using Sliding Mode Control (SMC) in Permanent Magnet Synchronous Machines (PMSMs) is presented. The novelty of this paper is the fact that the SMC is used instead of the conventional Field Oriented Control (FOC) and therefore the injected HF test signals for tracking the machine´ saliency (difference between Ld and Lq) is naturally eliminated by the SMC. Such suppression is tackled when using the SMC and the position signals are calculated to properly estimate the permanent magnet (PM) position. Finally, some simulation results are presented, confirming the proper angle estimation at low speed reversal and load impact at zero speed.