Kawashima, Tomohiro

Japanese

Affiliation	Department of Electrical and Electronic Information Engineering
Title	Associate Professor
Fields of Research	Measurement, High Voltage, Electrical insulation,
Degree	Doctor of Engineering (Toyohashi University of Technology)
Academic Societies	Department of Electrical and Electronic Information Engineering
E-mail	kawashima@ee Please append ".tut.ac.jp" to the end of the address above.
Laboratory website URL	http://dei.ee.tut.ac.jp/
Researcher information URL（researchmap）	Researcher information

Research

Current electric power systems are diversifying from power generation to usage, for instance, the promotion of renewable energy and the spread of electric vehicles. On the other hand, the aging of power equipment that was introduced in large quantities during high economic growth is also a severe issue. It is crucial to quantitatively clarify the lifetime of the equipment and ensure a stable supply of electricity through appropriate updates, as well as to develop technology to realize next-generation power systems. We develop nondestructive high-voltage measurement technology that contributes to the condition diagnosis of power systems. We also aim to apply the developed technology to research fields such as steel, automobiles, and food.

Theme1：Deterioration Diagnosis of high voltage insulation systems by measuring partial discharges

Overview

Condition assessment of deterioration based on waveform characteristics of partial discharge

One cause of the deterioration of high-voltage insulation systems in power equipment is minute discharges, namely partial discharges. Measuring partial discharges with the broadest possible band and time series and then quantitatively evaluating the deterioration area and circumstances using the information of the waveform should help prevent severe accidents. In this research, we develop a deterioration diagnosis technology using a time-series analysis of partial discharge waveform characteristics. We also aim to assess the condition of the deterioration and make predictions using machine learning.

Keywords

Partial discharge, waveform characteristics, deterioration diagnosis, time-series analysis, machine learning, prediction

Theme2：High voltage dielectric spectrum measurement and its applications

Overview

Dielectric properties at high voltages are mainly evaluated using bridge circuits. Since transformers can apply as voltage sources, obtaining high voltages is easy; however, it is often difficult to sweep the frequency. The frequency spectrum at high voltages allows us to evaluate, for example, nonlinear charge behavior related to degradation. We develop a deterioration diagnosis technology for power equipment using high voltage dielectric spectrum analysis. In addition, we aim to apply this technology to the operation assessment of high-voltage actuators and real-time non-destructive diagnosis of food products.

Keywords

High voltage, dielectric spectrum, charge behavior, condition diagnosis