所報 103

9/50

－　　－7Published PaperFlywheel size design considerations and experimental verication using a 50-kW system for voltage sag compensator with ywheel induction motorShuhei KATO, Cheng MIAO-MIAO, Hideo SUMITANI and Ryuichi SHIMADAWith increased automation of factories, the quality of electric power is becoming more important. The main factor contributing to electric power disturbances is voltage sags (dips), which are a few tenths of a second in duration. These voltage sags occur 10 times more often than blackouts and outages of several minutes’ duration, and constitute a major problem that causes serious loss in industry. In order to prevent these power disturbances, there are two types of com-pensation methods: (I) Series compensation method called DVR (Dynamic Voltage Restorer injects compensating volt-ages in series to the power lines through series transformers; and (II) Parallel compensation method which makes the toggle switch operation from the power grid under voltage sag to voltage source inverter using a battery or an EDLC (electrical double layer capacitor) to prevent the voltage sag. Although the above solutions by DVR, the battery, and EDLC have many advantages, there are still problems such as many semiconductor power converters, its filters, and environmental problems in terms of the battery.In order to solve these issues, this paper proposes one of the parallel compensation methods by the simplest flywheel system. This flywheel solution works as a capacitor self-excited induction generator (SEIG) when voltage sags without a semiconductor converter. In the final section, the proposed flywheel system is applied to the short-term compensation for safety shutdown of industry robots when the power grid experiences blackouts. The effect of the flywheel system can be confirmed by field experiment test results of a 30-kVA real industry robot safety shutdown.Keywords: flywheel, voltage sag compensator, induction motor, capacitor self-excitationフライホイール誘導機式瞬低保護装置の貯蔵容量設計と50kW機による実験的検証　ロボットによる自動化された生産工場は年々増え続けている。これらの工場において電力系統の停電は深刻な問題となっている。これに対して従来はリチウムイオン等の蓄電池によるバックアップ電源を用意し、停電時に無瞬断で切り替える方式が採用されてきた。しかし蓄電池は短寿命や廃棄時に環境負荷が大きいといった課題がある。この課題に対して本論文はフライホイールと呼ばれる慣性大なる回転体の運動エネルギーとして電力を貯蔵する仕組みに着目した。フライホイールに簡素なかご型誘導電動発電機を接続した50 kWのフライホイール電動発電機を製作し、停電時に無瞬断でフライホイール電動発電機に切り替える実証実験により性能を検証した。本フライホイール電動発電機は停電対策という一時的な利用だけでなく、生産工場の昼間電力ピークカット等の連続利用へも応用可能なため、幅広い波及効果が期待できる。キーワード：フライホイール，瞬低保護装置，かご型誘導電動機，キャパシタ自励現象Journal （掲載誌）電気学会論文誌 D部門 vol. 129, Issue 5, pp.446-452, 2009, IEEJ Transactions on Industry Applications