FUNATO Hirohito

Wireless electric power distribution is an attractive means of supplying power to mobile equipment such as mobile phones and electric vehicles. Magnetic field coupling is the most popular method for wireless power distribution. However, this metho...

Recently, global warming has become a major problem. Therefore, the development of technologies for generating clean energy without producing CO₂ is required. Micro-hydroelectric power generation is one of the promising options as it re...

The higher efficiency and the low noise in output voltage and current has been required in some applications, i.e. audio-video equipment, medical equipment and so on. This paper proposes a power amplifier in which a PWM inverter is used as a main ...

This paper analyzes shaft voltage and bearing current in a nongrounded motor driven by a voltage-source PWM inverter. First, the shaft voltage of the nongrounded motor is measured. The experimental results indicate that a bearing current, which ca...

This paper develops a probe for measuring the high frequency grounding potential and demonstrates its effectiveness. The developed probe is applied to a motor drive system and measures a potential difference between a grounding terminal and the mo...

The objective of this study is to find out a simple, time and cost-effective method for the assessment of state of batteries. In this study, the targets of estimation are NiCd, NiMH batteries that are widely used in portable equipments, but are di...

In high performance active vibration control for a flexible structure, it is requirement to establish an accurate model identified not only 1^st but also 2^nd and 3^rd vibration modes of the flexi...

In this paper, the authors will propose a new predictive instantaneous current control method taking into account AC side LC filters in three phase PWM voltage-source rectifiers. This method is based on predeictive-instantaneous-current control, s...

At every switching time, a PWM inverter produces high-frequency leakage currents flowing through stray capacitors. As the inverter for a trash conveyance crane is installed far away from a motor, shield power cables between them become long, leaka...

This paper introduces how to identify the parameters of the general equivalent circuit of induction motors. This method is implemented by using the system identification while no induction motor operates. The results have been compared with other ...

Inductance has particularly important role in power circuits. Authors have proposed the Variable ActivePassive Reactance (VAPAR) which can produce a virtual variable inductance. In this paper, the transient power characteristics of a balanced thre...

The torsional vibration is often initiated by the momentary impact which occurs when a load is connected to a motor by several mechanical coupling parts. An industrial servo system is basically represented as a multi-mass system. To suppress the v...

The authors have proposed the VAPAR (Variable Active-Passive Reactance Circuit) which can generate not only a positive reactance but also a negative reactance applicable to a power circuit. To help understanding of a negative inductance, at first,...

Torsional vibration suppression control is a very important subject in a recent servo system. To overcome the torsional vibration, various control strategies have been proposed such as resonance ratio control, state feedback and &Eta;_&infin;<...

A new estimation method of the state of the charge of a lead-acid battery is proposed. This method is based on both the electromotive force and the internal resistance of a battery. The estimating equation is derived from a mesured data using the ...

The torsional vibration is often initiated by the momentary impact which occurs when a load is connected to aa motor by several mechanical coupling parts. To suppress the vibration generated in a multi-mass plant, many control methods have been de...

The torsional vibration is often initiated by the momentary impact which occurs when a load is connected to a motor by several mechanical coupling parts. An industrial motor drive system is typically represented as a two-mass plant. To suppress th...

This paper describes a first-order H&infin; speed controller which can well regulate load speed without torsional vibration for both speed reference and torque disturbance in a two-mass resonant system. To the strategy for reducing the orde...