Y. J. Bao

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.

Research on a novel switched reluctance generator for wind power generation

For conventional generators for wind power generation, low speed operation and large power are difficult to be achieved. However, significant improvement of the above performances can be achieved by the developed novel switched reluctance generator. Furthermore, the developed SRG is sample and more reliable than conventional generators since it is composed of a specified number of independent generation units, which are installed easily on site. Firstly, a developed novel switched reluctance generator is present, and then the actual behavior and typical waveforms of the novel switched reluctance generator are discussed according to the actual testing. In addition to the mechanical aspect of novel switched reluctance generator, due attention is given to the control aspect is considered for wind power generator system implementation. The novel controller designed for this novel generator is given and it can fit the generation pattern of the wind power generation. The proposed machine is the first SRG for wind power generation in the world using a parallel modular approach.

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.

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.

Design consideration of C-core switched reluctance generators for wind energy

In this study, the C-core switched reluctance generator is developed for wind energy. A C-core switched reluctance generator includes a number of the stator C-cores and a number of the rotor poles. For the C-core switched reluctance generator, each phase has the independent stator C-core and flux path. The phase winding is on the stator C-core and there is no any winding on rotor poles. This machine has the following main advantages: (a) the simple and reliable configuration, (b) the flexible controllability, (c) the low cost, (d) the redundancy features, (e) the independent stator C-core structure and the independent flux path, (f) the rotor with low weight, and (g) the low speed operation. The energy conversion and design consideration of the proposed C-core switched reluctance generator will be discussed. This paper provides a new type of switched reluctance generator for wind power generation.

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.

Integral sliding mode control and its application on active suspension system

Active suspension system is a hot issue in the recent research of automotive industry, which is to generate active force to suppress the variation of the vehicle and improve safety and comfort for the passengers. By observing the dynamics of the vehicle, the controller output forces through linear actuators. Integral sliding mode control is applied here to calculate the output forces and then reject the disturbance. In this paper, an accurate nonlinear active suspension system model is developed first; decoupling of the sprung mass subsystem is investigated hereafter to isolate the dependence of the variables, then integral sliding mode control is used to reject the disturbance and reach the referenced surface for each subsystem. PID control, as a conventional control method, is compared here with the integral sliding mode control. The simulation results show the effectiveness of the proposed control method.

Adaptive fuzzy tracking control for linear motor driven compressor

Linear compressors driven by a linear motor have attracted wide attention in cooling equipments. The nonlinear characteristics of linear compressor make it difficult to use a conventional feedback controller over a wide range of operation. In this paper, an adaptive fuzzy control is designed that can control the piston stroke of a linear compressor to a desired trajectory. The performance of the control algorithm of the linear compressor is verified through simulation.

Experimental study of automotive interleaved boost converter for PV systems

DC/DC boost converter is usually selected in many applications which a low voltage needs to be stepped up. In the applications of the power rating of several kilowatts, interleaved boost converter (IBC) is excellent solution because it has better performance characteristics when compared to conventional boost converter. IBC has two single boost converters in parallel. As a result, the ripple of input current is minimized and the efficiency of power converter is improved. This paper is focused on the high efficiency boost converter realized by the improvements of hardware and algorithm.

A novel analytical model of air-gap permeance in tubular linear switched reluctance actuators with hybrid flux paths

Due to simple and robust configuration, and without any coils and magnets on movers, a tubular linear switched reluctance actuator (TLSRA) is a promising candidate for applications of frequently reciprocating linear motion, such as linear compressors and automotive active suspension systems. For air-gap in a TLSRA, there are the longitudinal and transverse magnetic paths due to various mover positions. Change in air-gap permeance in a TLSRA results in the thrust force, which drives the mover for linear motion. Thus, the air-gap permeance is the crucial parameter for computing the thrust force in the electromagnetic design and estimating the real-time thrust force in force control of TLSRAs. In general, the air-gap permeance at two special positions can be calculated analytically, such as the maximum and minimum air-gap permeance. It is a challenging issue that an analytically model is developed to compute the air-gap permeance at arbitrary mover positions. This paper focuses on that permeance model development.