榦間に永久磁石を挿入した突榦形同期発電檆

摘要

突極形同期発電機は，水力発電機・エンジン発電機などrnに使用されている重要な機器である。この突極形同期発電rn機の問題点として磁極の磁気飽和がある。磁気飽和によっrnて，端子電圧が制限を受け，無用な界磁起磁力を消費する。rnそこで，本稿では，磁極の磁気飽和低減を目的に，隣接rnする磁極端の間に永久磁石（PM）を挿入したPM補助究極rn形同期発電機（PMa-SG）を提案する。%In this paper, a new salient-pole synchronous generator (SG) termed the PMa-SG is presented. In the PMa-SG, permanent magnets (PMs) are placed between the pole shoes to reduce the magnetic saturation in the field poles. By using finite element analysis (FEA), the internal magnetic fields and basic characteristics of a 2.8-MVA PMa-SG were compared with those of a conventional SG of the same size, and the reduction effect of the magnetic saturation of the PMs was examined. The FEA simulations were also validated by experiments on a 2.0-kVA prototype machine. The PMs placed between the pole shoes reduce the magnetic saturation in the pole bodies and pole tips and effectively increase the terminal voltage and output power.