General Topology Derivation Methods and Control Strategies of Field Winding-Based Flux Adjustable PM Machines for Generator System in More Electric Aircraft

Abstract

The field winding-based flux adjustable permanent magnet (FWFAPM) machines, including the hybrid excitation (HE) topology and the memory topology, can offer excellent capabilities in terms of flux regulation, wide constant power operation as well as de-excitation (flux-weakening) under fault; thus, they are capable for use in More Electric Aircraft (MEA) generator systems. First, this article probes four basic HE modes, and based on that, a general method deriving permanent magnet (PM) machines to HE machines is established. The basic characteristics of each HE mode considering the relationship between S-pole and N-pole are obtained for the first time. The performance differences of each HE mode combined with different PM machines are summarized. Then, this general topology derivation method is extended for the memory topology. The unified derivation method of the single-PM topologies, the double-PM topologies, and the triple-PM topologies for memory machines is systematically established. The general laws of the electromagnetic performance of each double-PM mode and triple-PM mode considering different relationships between NdFeB and AlNiCo are summarized for the first time. Finally, the control strategies for voltage regulation of aircraft generator systems are discussed based on the different critical control variables and controller types; a torque impulse balance control method which shows excellent dynamic performance for both target control variable and critical control variable has been achieved experimentally.