High speed large capacity inverter for power system apparatus

This paper presents a large capacity inverter for power system apparatus that can simultaneously fulfil the tasks of: inverter loss reduction, harmonic reduction, and system disturbance control. The inverter consists of a hybrid inverter of a GTO inverter and an IGBT inverter. This paper presents the main circuit configuration of this hybrid inverter and outlines the inverter control system. For the purpose of confirming the capabilities of this inverter to solve the second and third tasks, the authors performed computer simulation of hybrid inverter applied to fuel cell power generation using EMTDC (Electromagnetic Transient Simulation Program). Harmonic characteristics in steady state and transient characteristics of system voltage dip are analyzed. The results reveal that the inverter system has capabilities to reduce harmonics and to control system disturbances. The inverter system can contribute to the wider use for power system apparatus.