| 摘要 |
PROBLEM TO BE SOLVED: To prevent the generation of noise and the concentration of excess heavy load on a specific circuit unit if a failure condition resulting in current cutting-off occurs in one unit, cutting off current to the other units almost at the same time, in parallel-operating a plurality of circuit units for electric power. SOLUTION: This device is provided with IGBT elements 10 driven with a plurality of IGBT elements connected in parallel, control units 6 controlling the respective IGBT elements 10 individually, a failure detecting circuit detecting a failure condition in the corresponding control unit 6 if a failure condition occurs, protection circuits cutting off the corresponding IGBT element 10 in the control unit 6, and error signal buses 16 activating in batch the protection circuits in all the control units 6. When a failure condition is detected by at least one control unit 6, the failure detecting circuit makes the protection circuits of all of the control units 6 via the error signal bus 16 are activated, and all of the IGBT elements 10 are cut off in batch. |
