| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage type multilevel converter that performs a protection process against a short circuit fault without requiring a higher communication speed between a common controller and a controller in a phase module and in a simple configuration.SOLUTION: Flying capacitors C3, C4 disposed for each phase and charged with a different voltage from capacitors C1, C2 are provided with voltage change rate detection sections 2a, 2b for detecting rates of change in voltage across the flying capacitors C3, C4, and if the rates of change in voltage across the flying capacitors C3, C4 exceed a threshold, a short circuit is detected. A short circuit anomaly signal is then transmitted to a controller section 6 of each phase, and a drive circuit 7 for each switching element interrupts a gate signal. |
