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This paper describes a consideration of the excitation circuit of a switched reluctance (SR) generator. The SR generator has some features including solid structure and easiness of maintenance. However, the conventional excitation circuit of the SR generator is an asymmetry half bridge converter (AHBC) whose configuration is complicated. In this paper, we examine the operating characteristics of the SR generator excited by a suppression resistor converter (SRC) based on finite-element method (FEM) analysis and experiments. Index Terms--Finite-element method (FEM) analysis, suppression resistor converter, switched reluctance generator.

In sensorless driving of permanent-magnet synchronous motors, it is difficult to deal with the nonlinear characteristic of the magnetic circuit and the harmonics of magnetic density distribution in the air gap. Using a neural network has been considered to be a powerful tool but, unfortunately, only few simulation-based works can be found. In this paper, an experiment system and successful experiment results using our proposed sensorless driving method of permanent-magnet synchronous motors based on neural networks will he presented. The method estimates the position errors from electromotive force instead of directly estimating the position using neural networks and then using the approximate algorithm to obtain the rotor position. Experiment results show that the method has excellent possibility in practical applications. Index Terms--Approximate algorithm, magnet synchronous motors, neural networks, position-sensorless driving.

A method for calculating the dynamic characteristics of Switched Reluctance Motor (SRM) has been proposed. The inductance model of SRM that is changed following the rotor position can be estimated from FEM analysis. based on the model, we design a circuit simulation of SRM using SPICE, which can simulate voltages, currents, torque and rotation speed of the SRM. Index terms - Switched Reluctance Motor, Reluctance, Dynamic characteristics, Circuit simulation

This paper deals with transient operation of the orthogonal-core type dc-ac converter for grid connection type photovoltaic power system. Particularly, we discuss the transient operation when the converter is connected to and disconnected from the utility grid based on simulation and experiment. Furthermore, we examine the converter behavior when a line-to-line fault occurs in the utility grid. Some useful information for the system design was obtained in this paper.

This paper deals with the push-pull parametric transformer. The parametric transformer has voltage regulation, overload protection and a kind of filter function for harmonic currents produced by nonlinear loads. The operating characteristics of the push-pull parametric transformer with resistive load are discussed. Furthermore, we demonstrate the operation of the push-pull parametric transformer with a thyristor rectifier circuit as an example of a nonlinear load.

This paper presents a new calculation model of the switched reluctance motor (SRM) for use on SPICE which is a general-purpose circuit simulation program. In the calculation model, the electric circuit and magnetic circuit of SRM are separated and are coupled by proper controlled sources. Using the SPICE model, we can calculate readily and accurately the dynamic characteristics of the SRM. Index Terms--Dynamic characteristics, numerical analysis, SPICE, SRM.

We propose a new sensorless drive method of Switched Reluctance Motor (SRM) based on motor's magnetic characteristics. Some drawbacks of the method using impressed voltage pulse at unenergized phases to detect the magnetic characteristic have been improved. The proposed method has the features: only one unenergized phase has been injected by impressed voltage pulse, that simplifies both hardware and control algorithm, and a new idea to determining the injecting timing for impressed voltage pulse has been introduced, that extremely eliminates the negative torque caused by some residual currents. Because the proposed method is very simple, instead of expensive DSP, the entire experimental system has been implemented in an analog and digital circuit (FPGA: Field Programmable Gate Array). Index Terms--FPGA, inductance, position sensorless drives, switched reluctance motor.

Focuses on a study which dealt with a numerical model of orthogonal-core transformers for use in SPICE. Basis on which the model is devised; Suitability of the model; Need to predict circuit behavior considering the non-linear characteristics of orthogonal-core transformers.

Describes a two c-core type orthogonal-core made of iron and silicon sheet and its application to power converters. Diagram of the c-core for the orthogonal-core; Relations between the core loss and the maximum flux density; Converter for coupling two independent direct current power sources.

Describes performance characteristics of a direct current (dc) detector using bridge-connected magnetic circuit. Fundamental operations; Application to a dc current detector; Conclusion.