Double Stator Switched Reluctance Machine Research Articles

A Double-Stator Switched Reluctance Motor for Direct-Drive Washing Machine Application

Abstract. Switched reluctance motors (SRMs) are known as an economical solution by several unique features such as: simple structure and low cost maintenance. Furthermore, due to the lack of permanent magnet, powerful and economical structure of these types of motors, they are proposed as a good choice for use in household appliances. In this paper, a high power flat-type double-stator SRM with low operating voltage in direct-drive system is introduced. Initially, proportional to the intended application, the acceptable attribute of SRM structure is selected, and was followed by the calculation of the motor design. Next, the magnetic characteristics are analyzed by finite element method (FEM) to determine the efficiency of the motor. Finally, the collection of experimental data is tested to confirm the calculated values and the simulation results and ensure the proper functioning of the obtained collection.

Rotor Shape Investigation and Optimization of Double Stator Switched Reluctance Machine

This paper presents an optimal design for the rotor of a double stator switched reluctance machine. The effect of the rotor shape on the torque profile is analyzed first. Due to the nonlinearity of magnetic core and complex geometry, an iterative approach is developed to automatically shape the rotor geometry using static finite element method. The rotor of a 12/8/12 prototype is optimized. Simulation results validate the effectiveness of the optimal design.

Optimum Rotor Shaping for Torque Improvement of Double Stator Switched Reluctance Motor

Although the power density in Double Stator Switched Reluctance Motor (DSSRM) has been improved, the torque ripple is still very high. So, it is important to reduce the torque ripple for specific applications such as Electric Vehicles (EVs). In This paper, an effective rotor shaping optimization technique for torque ripple reduction of DSSRM is presented. This method leads to the lower torque pulsation without significant reduction in the average torque. The method is based on shape optimization of the rotor using Finite Element Method and Taguchi’s optimization method for rotor reshaping for redistribution of the flux so that the phase inductance profile has smoother variation as the rotor poles move into alignment with excited stator poles. To check on new design robustness, mechanical analysis was used to evaluate structural conformity against local electromagnetic forces which cause vibration and deformation. The results show that this shape optimization technique has profound effect on the torque ripple reduction.

Comparison of Mechanical Vibration Between a Double-Stator Switched Reluctance Machine and a Conventional Switched Reluctance Machine

Vibration and acoustic noises are viewed as a drawback in switched reluctance machines (SRMs), which prohibit their widespread use in noise sensitive applications. Double-stator SRMs (DSSRMs) can be considered as a solution to this problem by incorporating an improved magnetic configuration, which reduces the radial forces in the machine. This paper compares structural behavior of a DSSRM and a conventional SRM using a multi-physic analysis. An electromagnetic finite-element (FE) method is used to calculate force density at various parts of the stator surface in both machines. These force densities are then used in a structural FE analysis to compute acceleration, deformation, and velocity of the vibrating surface at selected point on the outer surface of the machine.

Quantitative Comparison and Analysis of Magnetless Machines With Reluctance Topologies

This paper quantitatively compares three advanced magnetless machines, namely the switched reluctance (SR) machine, double-stator SR (DS-SR) machine and DS multitoothed SR (DS-MSR) machine. The DS-SR machine is particularly favorable for low-torque highspeed operation while the DS-MSR machine is desirable for high-torque low-speed operation. Because of more effective power transfer by using two stators, the two DS machines achieve better performances than the single-stator counterpart. All machine performances are analyzed by using the time-stepping finite element method.

Torque Optimization of Double-Stator Switched Reluctance Machine

Double-stator switched reluctance machines benefit from a high torque density and a low radial force level in comparison with conventional switched reluctance machines resulting in a lower vibration and acoustic noise. Therefore, they are suitable candidate for automotive applications. However, torque pulsation which is also a source for vibration is still remained and should be alleviate by dimension optimization of the machine. This paper presents a design optimization of a double-stator switched reluctance machine for improving the magnetic torque quality of the machine. For this purpose finite element method along with response surface methodology is used to optimize three parameters of the machine to maximize torque quality factor i.e. the average torque to torque ripple ratio in the machine. Genetic algorithm method is also employed as an optimization tool. The aim of optimization is to maximize the ratio of average torque to torque ripple. Finite element results are presented to verify the optimization method.

Characteristics Analysis of Short Flux Path Switched Reluctance Motor

A novel kind of switched reluctance motor (SRM) with short flux path is proposed in this paper. Phase excitation in the SRM gives short flux paths, hence reducing the magnetomotive force required to drive the machine, resulting in significant reduction of copper wire and core losses compared to the typical SRM with diametric circulation of magnetic flux. To verify the performance, the characteristics analysis of a double-stator SRM, a 6/5 SRM with C-core structure, and a 4/5 two-phase SRM, which all have short flux paths, and a comparison with conventional SR motors are executed. The comparison demonstrates that the proposed motor offers some advantages in terms of torque and efficiency.