Research On Simulation And Development Of Switch Reluctance Motor Drive

Switched reluctance motor drive (SRD) is a new generation of motor drive which hasdeveloped gradually following AC and DC motor drive, and it has been widely used in kinds ofdrive fields nowadays. Compared with AC and DC motor, switched reluctance motor (SRM) haslots of advantages such as simpler structure, lower cost and more flexible control. Therefore, it hasattracted the attention of experts and scholars at home and abroad. However, owing to its specialdoubly salient structure and switching power supply mode, the SRM’s flux and current is highlynonlinear, and the problem of its torque ripple is particularly serious. It not only increases thedifficulty of control, but also limits the applications. Thus, studying on SRD is of great significancefor popularizing its applications in reality.Firstly, the mathematical model and traditional control methods of switched reluctance motorare introduced on the basis of its basic structure and operating principle in this paper. After that, thelinear model of three-phase6/4SRM, the nonlinear model of three-phase6/4SRM and four-phase8/6SRM are simulated under traditional chopped current control. According to the simulationresults, the linear model and nonlinear model are compared, and the differences of performancebetween SRMs of different phase are also analyzed.Secondly, based on the basic principle of direct torque control (DTC) of SRM, the selectionrules of voltage vector and the calculation method of flux vector of four-phase8/6SRM are studied,and a judgement method of flux sector suitable for arbitrary phase SRM is proposed in the paper.Using simulink modules, direct torque control of four-phase8/6SRM was realized inMATLAB/Simulink environment, and the outstanding effect of DTC on flux control and torqueripple reduction of SRM is proved through simulation and comparison with the traditional controlmethod.Using the hardware design scheme of others for reference, a set of switched reluctance motordrive is developed. The principle and features of the hardware circuit as well as the function andprocess of the software program are introduced in detail. The hardware circuit of the SRD includesa control circuit with digital signal processor (DSP) TMS320F2812PGFA as the core and a powerdrive circuit consisting of rectifier circuit, the main circuit of power converter, optocoupler andtrigger circuit and current sensing circuit. While the software program of the SRD is composed oftwo parts, which is the DSP control program of lower computer and the LabVIEW interface ofupper computer.Finally, multiple experiments on SRD are done based on the developed experimental platform. The advantages and disadvantages between starting directly with a high voltage and starting with agradually rising voltage are compared. In addition, the speed control and torque control are realized.As a result, the correctness and effectiveness of software and hardware design of the developedSRD are verifed. The research in this paper can provide a good foundation for further theoreticaland experimental research of switched reluctance motor.