Toshiaki Murata

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This paper proposes a fuzzy-logic-controlled superconducting magnetic energy storage (SMES) scheme for the stabilization of grid-connected wind-generator systems. The control scheme of SMES is based on a sinusoidal pulsewidth-modulation voltage-source converter and a two-quadrant dc-dc chopper using an insulated-gate bipolar transistor. A comparative study(More)
This paper presents a field oriented direct torque control system in permanent magnet synchronous motor (PMSM) which controls torque directly as output. A PWM inverter-fed PMSM control system has been driven by field oriented control algorithm without chattering by sliding mode control. The validity of the proposed method is confirmed by simulation results
This paper analyzes different types of symmetrical and unsymmetrical fault of grid connected wind turbine generator system (WTGS), where the six-mass drive train model is considered. The unsuccessful re-closing due to permanent fault is also considered. Moreover, the blade-shaft stresses of the six-mass drive train model of WTGS are also analysed for both(More)
This paper presents a field oriented direct torque control system in Interior Permanent Magnet Synchronous Motor (IPMSM) which controls torque to be the maximum and flux to be the minimum simultaneously. In order to control torque directly, a concept of magnetic energy conversion is introduced. A state space model described by magnetic energies which one is(More)
Since a superconducting magnetic energy storage (SMES) unit with a self-commutated converter is capable of controlling both the active and reactive power simultaneously and quickly, increasing attention has been focused recently on power system stabilization by SMES control. In this study, a fuzzy gain scheduled supplementary control scheme with SMES unit(More)
In this paper, the modeling and simulation process of space vector pulse width modulation (SVPWM) technique is presented using PSCAD/EMTDC because it has so far still not been reported for PSCAD user base. To demonstrate the implementation of SVPWM technique the well-known voltage source converter (VSC) based STATCOM is chosen. Both of the steady state and(More)
This paper analyzes the influence of communication delays introduced in online calculation of the global input variable of the fuzzy logic controller for braking resistor (BR) switching on the transient stability of a multi-machine power system. The time derivative of the total kinetic energy deviation (D) of the synchronous generators is used as the global(More)
Recently, interior permanent magnet synchronous motors (IPMSMs) are becoming more used due to the powerful magnetic characteristic of the rare earth, being used in different areas. Several researchers have proposed implementations combining the use of IPMSM with the direct torque control (DTC) technique offering a quick and precise control. However, DTC can(More)
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