A Wound-Field Pole-Changing Vernier Machine for Electric Vehicles

Abstract

This paper proposes a wound field pole changing vernier machine with fractional slot concentrated winding for electric vehicles application. The main aim of the paper is to utilize the advantages of a vernier machine and a wound field synchronous machine in a single topology using a fractional slot concentrated armature winding. The proposed machine operates in a vernier mode at low speeds and a wound-field synchronous mode at high speeds to utilize the merits of both a vernier machine and a wound-field synchronous machine. The topology, operating principle and pole-changing method of the proposed machine are explained initially. Then, finite element analysis (FEA) is utilized to study the electromagnetic characteristics such as back EMF, torque, wide speed range operation and efficiency of the proposed topology in two modes. Further, a prototype of the machine is manufactured and the FEA results are validated through experiments. The FEA and experiment results show that the proposed machine is a promising candidate for electric vehicles application. INDEX TERMS Electric vehicles, pole changing, wound field synchronous machine, variable speed, vernier machine.

Electronic Pole-Changing Strategy with Cosine-Response for Multiphase Induction Motor Based on PR Controller

“…The electronic pole-**changing process of ramp response is as follows: Change from one pair poles to two pairs poles mode, that is, from d 1 -q 1 to d 2 -q 2 , i 1qs from the reference value i * 1qs to zero in proportion to time, i 2qs increased from zero to the reference value i * 2qs in proportion to time. The torque current switching mathematic formula is showed as (7). In the research, it is found that the excitation current is given in proportion to time, which will cause flux unsaturated and aggravate the torque fluctuation.…”

“…[1][2][3][4][5]. For example, in the electric vehicle driving system, it is required to provide large torque at low speed and a wide speed range, and the MIM can meet the requirements by using the pole-changing strategy, which is both efficient and convenient [6][7][8]. Therefore, it has been extensively studied.…”

Design and Analysis of Single Inverter-Fed Brushless Wound Rotor Vernier Machine

“…Moreover, the brushless topology avoids the problems of sparking and regular maintenance in rotor-current-excited vernier machines. In [15], a topology of the wound rotor machine with dual-mode was proposed. Dual mode operation was created by portioning the field winding into two groups to generate different rotor poles by changing field coils arrangements.…”

Two-dimensional analytical model for five-phase fault-tolerant permanent-magnet vernier machines

“…This feature stops the effect of one-phase fault on the remaining phases by inherently negligible coupling between phases (Liu et al , 2012). Baloch et al (2020) introduced a novel vernier machine topology for EV applications by combining the merits of a vernier motor and a wound field synchronous machine. Besides, a holistic approach fault-tolerant PMVMs was investigated by Zhao et al (2020).…”