大容量3レベルGTOインバータに適用可能な全回生スナバ回路方式の提案 Proposal of Newly Regenerative Snubber Circuit for Large Capacity 3-Level GTO Inverter System
Increase in the capacity of GTOs has made remarcable progress in recent years. At present, 4.5kV-4.0kA GTOs are commercially available. Now, 6kV-6kA GTOs which are made from 6-inch silicon wafer are developing. The 6-inch GTOs are going to be applied to our 3-level GTO inverter system. In order to apply GTOs to voltage-source-inverters snubber circuits are necessary for limiting on turn-on di/dt and turn-off dv/dt. To realize the system of high efficiency, regenerative snubber circuit is applied. A conventional circuit, which could be applied to 3-level GTO inverter, had a problem that long paths are created for snubber circuits of inner GTOs. In order to solve the problem, a circuit using a transformer which is provided for recovering the trapped energy of snubber circuits for inner GTOs was presented. In this paper, newly regenerative snubber circuit is proposed, which is more suitable for 3-level GTO inverter system with many phase-legs. By applying this snubber circuit, snubber energy generated by the switching of all GTOs' in the main circuit can be regenerated to DC-link capacitors. High turn-off capability of both inner GTO and outer GTOs are verified by several successful experimental results using 6-inch (6kV, 6kA) GTO.
- 電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society
電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society 117(2), 189-195, 1997-02
The Institute of Electrical Engineers of Japan