Research On Characteristic About External-rotor Doubly Salient Electro-magnet Machine Used As A Roller Driver

In recent years, the application of belt is used more and more widely, as an important component of motorized pulley, the performance of the belt conveyor is determined by the quality of the motor. DSEM is a new specific motor developed in recent years, it has simple structure, high reliability, high temperature resistance, high power density and high efficiency. DSEM is creatively used as a roller drive motor in this paper and it realized the function of direct driving the motorized pulley with low speed and high torque.This paper is based on present achievements of DSEM and develops an outer-rotor 24/16-pole Doubly Salient Electro-Magnet(DSEM) and an inner-rotor 24/16-pole DSEM aimed at low-speed drum drive motor. Furthermore, this paper studies the designs of DSEM's structure, multi pole motor, structure parameters, static performance and steady-state performance of the motor. Besides, it analyzes the efficiency.Firstly, the paper introduces the development history of the motorized pulley and the shortcomings of existing roller drive motor and explains in detail the research status on DSEM at home and abroad, DSEM's structure, mathematical model and control modes of motor's drive and generation condition. Then, this paper researches the operating characteristics of multi-outer-rotor DSEM from the motor static and steady state characteristics. In terms of static characteristics, this paper emphatically studies the flux and inductance, cogging torque and so on in no-load power state. In terms of steady state characteristics, this paper under the electric load state studies flux linkage, back EMF, the inductance and the output torque with different control methods such as three phase three clap(TPTC), three phase-three clap with advance angle control(TPTC_AAC), three phase-six clap(TPSC), and three phase-six clap with advance angle control(TPSC_AAC). Static, steady and efficiency characteristics are analyzed, the structure of the motor is initially set as 24/16 pole.Then, the paper studies the influences to outer-rotor 24/16-pole DESM's performances and efficiency of different aspects such as gas length, the pole arc of rotor, axial length,the pole height of stator and auxiliary rotor slots in detail. The results can offer basis for outer-rotor 24/16-pole DESM design.Finally, the performances of inner and outer rotor DESM are compared. By comparison, the motor output, ratio of torque to current and so on of outer-rotor DESM are larger, but its efficiency is slightly smaller than that of the inner-rotor motor. Two kinds of motors are good to be roller driver motor, so different motors can be chosen according to the actual needs.