Indirect measurement and extreme learning machine based modelling for flux linkage of doubly salient electromagnetic machine

Abstract

Doubly salient electromagnetic machines (DSEMs), which are characterised with fault tolerance, low cost, high reliability, and de-excitation ability, are gaining more and more attention in safety-critical and hash environment applications, such as the aircraft generation systems. Nevertheless, the non-linear and strong coupled characteristics of the flux linkage is the obstruct crux in DSEM modelling. The DSEM model is the critical part of the system model, which is the foundation of theoretical analysis, control strategy developing, and stability analysis. This study is aimed to demonstrate the feasibility of indirect flux linkage measurement method, as well as the effectiveness of the extreme learning machine (ELM)-based flux linkage modelling method. The basic principles of the indirect measurement are analysed and the measurement processes excluding rotorclamping devices are proposed. The ELM is employed to high-precision flux linkage modelling with high efficiency. A threephase 12/8-pole DSEM is tested to confirm the validity of the proposed modelling method. Both finite element analysis and experimental results are presented, verifying the effectiveness of the indirect flux linkage measurement and the ELM-based modelling method. Fig. 12 Characteristics of the DSEM based on ELM flux linkage model, FEA simulation, and experiment (a) No-load characteristic, (b) Output characteristic

Coupling property analysis of the on‐board battery‐charging system based on DSEM in the charging mode

“…Another novel non‐permanent magnet machine with the same stator and rotor structure as SRM could also be the candidate for the driving system of the electric vehicle due to the low cost and high reliability [28, 29], while the operation principle of the doubly salient electromagnetic (DSEM) machine is obviously different to SRM due to the flexible field windings arrangement in the stator slots. Since the traditional DSEM has the variable inductance of phase winding with respect to the rotor position and output torque ripples due to the current commutation, an optimised 12/10‐pole DSEM with the distributed field windings is given in [30, 31], the trapezoidal back EMF waveform which is similar to the brushless direct current motor (BLDC) is achieved, and the property of lower torque ripples and the higher output performance compared to the traditional DSEM could be obtained for the traction applications in the electric vehicle.…”