Comparison of Three Speed Loop Designs for a High Speed Nine-phase Permanent Magnet Synchronous Machine in More Electric Aircraft

A high speed nine phase permanent magnet synchronous machine (PMSM) has been designed for more electric aircraft (MEA) for the sake of high power density and fault-tolerant capability. This paper addresses the speed loop design of the high speed PMSM by comparing three speed loop designs. For MEA, fast dynamic is not the primary demand, robustness against parameter variation and noise is the key requirement. For high speed machine, field weakening is not avoidable, therefore, maintaining the speed control during field weakening is also an important feature. This paper analyses the frequency response, stiffness and performance of the speed control with the three speed controllers, while the three controllers are tuned to provide the same control bandwidth. Simulation results validate the analysis. The pros and cons of each control design are summarised in the conclusion.