| 摘要 |
PROBLEM TO BE SOLVED: To detect the fault of a 3-phase motor controller quickly. SOLUTION: The current command signals IU, TV and IW of respective phases, which are outputted by a 3-phase distributor 1 in accordance with an input current command signal A, and a signal from a position detector 5, which obtains the electric angle of a 3-phase motor 4, are converted into command ratio signals IUO, IVO and IWO of the respective phases by a command ratio generator 10. On the other hand, the current detection signals IU1, IV1 and IW1 of the respective phases of the 3-phase motor 4 which are detected by current detectors 3U, 3V and 3W are converted into the detection ratio signals IU2, IV2 and IW2 of the respective phases by a detection ratio generator 11. The ratios of the command ratio signals IUO, IVO and IWO to the detection ratio signals IU2, IV2 and IW2 are obtained for the respective phases by a ratio judging device 12. If the ratio IUO/IU2, IVO/IV2 or IWO/IW2 of any one phase is out of a certain range, a fault detection signal C is outputted by the ratio judging device 12. |
