Effect of Objective Function Formulation on Static and Operating Parameters of a Switched Reluctance Motor After Optimization of Magnetic Circuit Shape

Purpose – The novel bearingless switched reluctance motor (BSRM) is proposed recently, which is different from the conventional BSRM in the stator structure and suspension winding arrangement. The reduced number of suspension windings makes the novel BSRM much simpler, so that the control circuit and algorithm are greatly simplified when compared to those of the conventional BSRM. This paper for the first time proposes the novel BSRM's analytic model, including the mathematical relationships among the winding currents, rotor angle, radial forces, and motor torque, to further achieve the suspending forces and torque control. The paper aims to discuss these issues. Design/methodology/approach – The magnetic equivalent circuit method is employed to obtain the self-inductances and mutual-inductances of the motor torque windings (main windings) and suspension windings (control windings). The straight flux paths are combined with the elliptical fringing flux paths to calculate the air-gap permeances, and the stored magnetic energy. Then, the mathematical expressions of radial forces and torque are derived. A novel BSRM prototype is analyzed through using the proposed analytical model and the finite element model. The results of both methods are compared to verify the proposed mathematical model. Findings – The proposed mathematical model of the novel BSRM considering unsaturated magnetic circuits is verified by finite-element analysis results. Research limitations/implications – The mathematical model represents the situation of magnetic circuit unsaturated and is not suitable for the magnetic circuit saturation. It cannot be used to control the motor which is working in the deep magnetic circuit saturation region. Practical implications – Building mathematical model is a necessary step for the motor's suspension and rotating control. The built model provides the fundamental for the preliminary control algorithm and experimental study of this novel BSRM. Originality/value – For the first time, the novel BSRM's mathematical model is proposed. It provides necessary fundamental for the motor's further analysis, design, and suspending and rotating controls.

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Optimal Design of Switched Reluctance Motor Using PSO Based FEM-EMC Modeling

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v5i5.pp887-895 ◽

2015 ◽

Vol 5 (5) ◽

pp. 887

Author(s):

Mouellef Sihem ◽

Bentounsi Amar ◽

Benalla Hocine

Keyword(s):

Magnetic Circuit ◽

Switched Reluctance Motor ◽

Pso Algorithm ◽

Torque Ripple ◽

Geometrical Parameters ◽

Swarm Optimization ◽

Switched Reluctance ◽

Reluctance Motor ◽

User Friendly ◽

Prototype Design

This paper aims to optimize the design of a prototype of a 6/4 Switched Reluctance Motor (SRM) using the Particle Swarm Optimization (PSO) algorithm. The geometrical parameters to optimize are the widths of the stator and rotor teeth due to their significant effects on the prototype design and the performances in terms of increased average torque and reduced torque ripple. The studied 3kW SRM is modeled using a numerical-analytical approach based on a coupled Finite Element Method with Equivalent Magnetic Circuit (FEM-EMC). The simulations are performed under MATLAB environment with user-friendly software. The optimal results found are discussed, compared against those obtained by the Genetic Algorithms (GA) and showed a significant improvement in average torque.

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Customized shape optimization of switched reluctance motor using B-Splines

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-07-2020-0250 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Ghassem Faezian ◽

Ahmad Darabi ◽

Nader Sargolzaei

Keyword(s):

Objective Function ◽

Optimization Design ◽

Switched Reluctance Motor ◽

Element Analysis ◽

Content Type ◽

Switched Reluctance ◽

B Splines ◽

Electromagnetic Devices ◽

Design Variables ◽

Reluctance Motor

Purpose This study aims to design the rotor geometry of switched reluctance motor (SRM) in a completely flexible way. In the proposed method, there is no default geometry for the rotor. The initial geometry of the rotor can start from a circle or any other shape and depending on the required performance takes the final shape during the optimal design. In this way, the best performance, possible with geometric design, can be achieved. Design/methodology/approach The rotor boundary of a 4/2 SRM is defined by a few B-splines. Some control points are located around the rotor and changing their locations causes customized changes in the rotor boundary. Locations of these points are defined as design variables. A 2-D finite element analysis using MATLAB/PDE is applied to the SRM model and sensitivity analysis is used to optimization design by means of minimizing of objective function. Findings The proposed method has many more capabilities for matching different objective functions. For the suggested objective function, while the conventional rotor torque profile difference with the desired torque profile reaches 40%, this difference for B-spline rotor is about 17%. Experimental results from a prototype motor have a close agreement with analysis results. Originality/value The B-splines have been used to design machines and electromagnetic devices. However, this method is used for the first time in design of the whole rotor of a SRM.

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Position Sensorless Control of Switched Reluctance Motor under Magnetic Field Saturation

E3S Web of Conferences ◽

10.1051/e3sconf/202125601040 ◽

2021 ◽

Vol 256 ◽

pp. 01040

Author(s):

Chunyuan Qiu ◽

Baojiang Sun

Keyword(s):

Magnetic Field ◽

Magnetic Circuit ◽

Control Method ◽

Sensorless Control ◽

Switched Reluctance Motor ◽

Switched Reluctance Motors ◽

Switched Reluctance ◽

Special Position ◽

Phase Current ◽

Reluctance Motor

When the switched reluctance motor is running, as the motor phase current increases, the magnetic circuit of the motor will gradually saturate, which affects the estimation of the special position of the motor rotor. Aiming at the above problems, this paper proposes a positionless control method for switched reluctance motors under the condition of magnetic field saturation. Firstly, the Fourier phase inductance function of switched reluctance motor is established, and then the component of Fourier phase inductance function affected by magnetic field saturation is eliminated mathematically. Research the method of estimating the position and angle of the rotor based on the inductance positioning point. This paper takes a 12\8 motor as an example to verify the effectiveness of the method by simulation.

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