Wei Li

Hysteresis Modeling for Electrical Steel Sheets Using Improved Vector Jiles-Atherton Hysteresis Model

To describe the vector magnetic hysteresis phenomenon of electrical steel sheets, an improved vector Jiles-Atherton hysteresis model is presented. The proposed model is developed based on Berqvist model. First, the anhysteretic magnetization function is improved by modifying the model parameters according to the excitation direction. By this, the modeling results are accurate under different alternating and nonsaturated rotating excitations. Furthermore, to model the magnetic property under saturated rotating excitations accurately, the proposed model is extended by modifying the model parameters according to the measured data. The proposed model is validated through comparisons between modeling and measured results under different alternating and rotating excitations.

An Adaptive Equivalent Circuit Modeling Method for the Eddy Current-Driven Electromechanical System

An adaptive equivalent circuit method is developed for analyzing eddy current-driven electromechanical systems in an efficient and accurate way. The problem is analyzed by transferring the system to an equivalent circuit model, which is set up by adaptively dividing the plate into a series of segments based on the field continuity condition at the interface of segments. The performance is obtained by solving the circuit equations combined with motional equations with the Runge-Kutta-Fehlberg method. The circuit parameters, such as self inductance and mutual inductance, are evaluated from the geometry parameters by using an analytic method. The proposed method is applied to analyze two eddy current-driven electromechanical systems, Thomson-coil actuators used for a practical engineering problem and TEAM Workshop Problem 28. The accuracy and efficiency of the proposed method are verified by comparing the calculation result with the FEM calculation result and the experimental result.

Optimal Design of a Thomson-Coil Actuator Utilizing a Mixed-Integer-Discrete-Continuous Variables Global Optimization Algorithm

To improve the performance of a Thomson-coil actuator, a new global optimization algorithm is proposed with mixed integer-discrete-continuous variables. In the algorithm, an augmented objective function is constructed by introducing a penalty function and an extended function to treat the discrete quantities as continuous ones. For the discrete objective function, two kinds of continuous function approximation methods, step function and linear function approximations, are suggested. The coupling particles swarm optimization method is then applied to the augmented objective function to find all the global and local optimal points. Finally, the validity of the proposed method is proven by comparing obtained optimization results with those from the enumeration algorithm.

Optimal shape design of a Thomson-coil actuator utilizing generalized topology modification based on equivalent circuit method

To improve the performance of a Thomson-coil actuator, a generalized topology optimization method was developed and applied to optimize the shape of the conducting plate. In this method, multiple solid materials were taken into account. A discrete material sensitivity was defined and calculated based on the equivalent circuit method. The selection of material to each segment depended on the discrete material sensitivity. A new topology of the conducting plate was obtained by using the generalized topology optimization method.To enhance the performance of a Thomson-coil actuator, generalized topology modification method is developed, and applied to the shape optimization of the conducting plate. In the method, shape optimization problem is treated as that of optimal assigning of material to each segment among available materials.

Analysis of Parameters Influence on the Characteristics of Thomson Coil Type Actuator of Arc Eliminator Using Adaptive Segmentation Equivalent Circuit Method

A Thomson coil type actuator is applied as the driving unit in an arc eliminator system. To eliminate the arc efficiently, the speed of the actuator is required as fast as possible with certain limit of the exciting current. Therefore, the dynamic characteristics of the Thomson coil type actuator should be analyzed in an effective way. In this paper, a novel solving technique has been developed based on the equivalent circuit model which is set up by dividing the conducting plate into multi segments. To guarantee the calculation accuracy and improve the calculation efficiency, an adaptive refinement algorithm is suggested based on the field continues condition. The proposed method has been verified by the FEM calculation and experiment. The influence of circuit and plate parameters to the performance of the actuator is also investigated, from which a reasonable set of parameters can be found.

Parametric analysis of Thomson-coil actuator using adaptive equivalent circuit method

Parametric analysis of Thomson-coil actuator has been done by utilizing the adaptive equivalent circuit method. Through the analysis of circuit parameters and plate dimensions, an optimal design of the actuator is obtained.