| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem of a PWM inverter that enhancement of carrier frequency is limited due to switching loss of a semiconductor switch. SOLUTION: Semiconductor switches Q1-Q8 are provided in parallel on the high voltage side and low voltage side of the arm of each phase U, V, W, respectively, and a gate controller GU performs on/off control of each switching sequentially while distributing at a carrier period of four times of frequency. On/off control of a plurality of switches at the same timing when the output current capacity of an inverter is increased, sustention of operation under gate control skipping a failed switch upon failure of a part of switches, and sustention of operation under gate control skipping a failed switch by blowing out a fuse in series with a failed switch through on control of a plurality of switches on the low voltage side or high voltage side reverse to the arm are also included. |
