N. C. Cheung

Switched Reluctance Generators with Hybrid Magnetic Paths for Wind Power Generation

The novel switched reluctance generator (SRG) with hybrid magnetic paths is developed for wind power generation in this paper. For the proposed SRG, there is no mutual coupling between phase windings. The proposed SRG has the longitudinal magnetic structure at the completely aligned position. However, it has the transverse and longitudinal magnetic structure at the unaligned position. Thus, three-dimensional finite element computation is needed in the design. The computed results based on three-dimensional finite-element analysis (FEA) are shown in the paper. Furthermore, the experimental results of the prototype demonstrate that the proposed SRG is feasible and effective.

A Novel Planar Switched Reluctance Motor for Industrial Applications

This paper presents a novel two-dimensional (2-D) planar switched reluctance motor (PSRM) for position control applications. The proposed 2-D planar motor has the advantages of simple mechanical construction, high reliability, and the ability to withstand hostile operating conditions. Due to the unique structure of the planar motors magnetic circuit, there is very little coupling between the X- and Z-axis, and no decoupling compensation is needed. It is expected that this innovative SR planar motion system will be an ideal replacement for traditional X-Y tables in industrial automation applications

Study of art of automotive active suspensions

In this study, research and development of automotive active suspensions are reviewed. Structures and models of various automotive suspensions are described. Furthermore, typical commercial products of automotive suspensions are illustrated. Based on the reported studies and development, the authors discus the comparisons between various vehicular suspensions from the aspects of structure, weight, cost, ride comfort, handling performance, reliability, dynamic performance, energy recovery, and commercial maturity. Consequently, it is deduced that electromagnetic active suspensions are the future trend of automotive suspensions due to simple structure, high-bandwidth, accurate and flexible force control, high ride quality, good handling performance, and energy regeneration. At the same time, the issues of future research and development of electromagnetic active suspensions are proposed.

Design and simulation of a linear switched reluctance generator for wave energy conversion

This paper investigates the direct-drive linear switched reluctance generator for wave energy conversion. A double-sided linear switched reluctance generator is designed. Its nonlinear flux characteristics are simulated by finite element method. The excitation circuit of the linear switched reluctance generator is reviewed and the control algorithm for this generator is also discussed.

Analysis and design of a cost effective converter for switched reluctance motor drives using component sharing

In this paper, a new and cost effective converter, consisting of “half-bridge” IGBT modules and SCRs, for switched reluctance motor drives is proposed. The new method allows the sharing of the IGBT bridge to the switched reluctance motors winding, thus it significantly reduce by half of the component cost. The proposed converter topology is a variation of the conventional asymmetric bridge converter for switched reluctance motor drives. However, utilization of switch modules is enhanced considerably. The requirements of switched reluctance motor drives on converters and the operation of the proposed converter are analyzed and discussed. Furthermore, the simulation and experimental results confirm the feasibility of the proposed converter.

Survey of modeling methods for flux linkage of switched reluctance motor

Switched reluctance motors (SRMs) have attracted many researchers and engineers attention, due to their advantages. However, its electromagnetic behaviors are very complicated and hard to be modeled. Therefore, modeling of flux linkage plays an important role for this type of machine. In this paper, some existed modeling methods of flux linkage for SRMs are surveyed. These modeling methods are fallen into seven classes according to their different features. Also, the advantages and limitations of these methods are discussed. Some considerations for selecting a proper modeling method are introduced form simulations and controller design, etc. Finally, the modeling methods are compared and evaluated based on the considerations.

Analysis and design of a Linear Switched Reluctance Motor with force improvement

Linear Switched Reluctance Motor (LSRM) is a potential candidate of traditional rotary-linear motors on many industrial applications. In this paper, a LSRM design procedure is presented to obtain the main dimensions of a LSRM. By adjusting some dimensions detailed, performance of a LSRM can be improved based on the main dimensions from the design procedure. The generated force is improved by using different pole-arc of mover and stator in this paper. Some simulations of a LSRM are performed in the platform of Maxwell. The results demonstrate that design procedure is effective for LSRM.

Investigation on parameters of automotive electromagnetic active suspensions

This paper presents the model of the electromagnetic active suspension consisting of an electromagnetic actuator and a mechanical spring. Furthermore, the authors investigate the effects of two crucial parameters, which are the spring stiffness and actuator force, on performances of the suspension. The study shows that the large spring stiffness results in the small initial displacement and requires the large actuator force, the small spring stiffness leads to the large initial displacement and needs the small force, and the large actuator force improves steady-state and dynamic performances and results in large volume, more weight and high cost of the actuator. Thus, this paper is considerable valuable for better designs of the electromagnetic active suspension and the actuator.

High precision position control of Linear Switched Reluctance Motor for short distance

In this paper, a passivity-based control (PBC) algorithm with disturbance reject is proposed to obtain precise position control of a Linear Switched Reluctance Motor (LSRM) driving system in short distance applications. In the framework of the two-time-scale analysis, the whole system is decomposed into two reduced-order models. With the models, an improved PBC algorithm is designed to reject the nonlinear friction in the outer loop. Three simulations are performed and the results demonstrate the improved control algorithm is effective for the LSRM position tracking system in short distance applications.

A controller for linear compressors propelled by linear switched reluctance actuators

A controller for the linear compressors propelled by the linear switched reluctance actuators is developed and presented in this paper. The controller is based on DSP TMS320F28335. It consists of the DSP circuit, the protection circuit, the multi-output DC supply, the current sensing circuit, the driving circuit, the AC-DC rectifier circuit, and the actuator converter. The double-loop control scheme is proposed and implemented. One of which is the closed-loop current control and the other is the closed-loop frequency control. The architecture of the controller and the control scheme are illustrated in the paper. The prototype of the proposed controller is developed. The experimental results demonstrate that the proposed controller is satisfactory and able to match the linear compressors propelled by linear switched reluctance actuators.