A large capacity 3-level IEGT inverter

Many large capacity motor drive equipments have been used in the steel plants. High-efficiency motor drive equipments are required in the industrial fields. On the other hand, the replacement demand of cycloconverter to VSI (Voltage Source Inverter) is also increasing. Normally, the VSI such as IGBT (Insulated Gate Bipolar Transistor) / IEGT (Injection Enhanced Gate Transistor) inverter has low-harmonics and high-efficiency. So, it has spread widely now. In this paper, it is introduced high-efficiency and large capacity 3-level IEGT inverter for steel plant application. It is realized 6MVA rated output capacity. With the series line-up of 3-level IEGT inverter, it is possible to combine with the early development of 9MVA IEGT inverter. Moreover, it has the flexibility to connect with a common converter and several numbers of inverters.