A Study of Practical Application on the Phase Conversion Transformer Using a Rotating Magnetic Field

1992 Fiscal Year Final Research Report Summary

• Project/Area Number: 03555052
• Research Category: Grant-in-Aid for Developmental Scientific Research (B)
• Allocation Type: Single-year Grants
• Research Field: 電力工学
• Research Institution: Hachinohe National College of Technology
• Principal Investigator: HIWATASHI Masaru Hachinohe National College of Technology, Electrical Engineering,Professor, 電気工学科, 教授 (80042109)
• Co-Investigator(Kenkyū-buntansha): KOBAYASHI Yuuji Tohoku Electric Power CO.,INC.,Technology Development, Assistant General Manager, 技術開発部, 副部長
• Project Period (FY): 1991 – 1992
• Keywords: Rotating Magnetic Field / Phase Conversion / Transformer / Trial Production / Space Harmonic Elimination / Multiple Inverter / Practical Application

Research Abstract

One of the basic method to improve waveform distortion of a semiconductor power converter is to construct a polyphase or multiple power system. Generally, the polyphase power system needs a large number of transformers, and as the number of phases increases, the number of transformers increases too. To improve the weakness and construct a polyphase power system with one apparatus, the phase conversion transformer using a rotating magnetic field was developed by authors.
The trial phase conversion transformer of small capacity was made with the process which is suitable for production in a factory, and was examined on the following subject. (1) Fundamental characteristic of t he transformer, (2) Primary load current waveform when the trial transformer was applied to a distribution system with distorted current load, (3) Output waveform when the trial trasformer was applied to construct a three-phase multiple inverter.
The results of these experiment are as follows: (1) Although the trial transformer was assembled using separated silicon steel plates, exciting current was small. Thus we can produce practical phase conversion transformers with the process. (2) To reduce harmonic distortion of a power system, we can utilize this phase conversion transformer for the power transformer used for an office building, for example. (3) We can utilize this phase conversion transformer for the apparatus to construct three-phase sine-wave inverter.
Polyphase or multiple power system that the number of phases is large don't be used usually, except for large power system, but using rotating magnetic field type phase conversion transformer, we can construct easily polyphase or multiple power system with one apparatus, regardless of the number of phases, therefore from this view point one may say that this phase conversion transformer is suitable for small power system.