ERROR DETECTION PROTECTOR FOR POWER SOURCE VOLTAGE PHASE SYNCHRONIZE SIGNAL IN ELEVATOR

摘要

The device is suitable for preventing mis-detection when detecting phase synchronized signal of power voltage necessary for synchronizing current command with power voltage phase and controlling input power ratio in the converter control section. The device having a potential transformer (1), a comparator (2), a primary synchronized signal detector (3), comprises a mis-detection preventing circuit (21) for generating signal of preventing mis-detection of phase synchronized signal after detecting the change of phase state; a secondary synchronized signal detecting section (22) for passing phase synchronized signal of the signal detector (3) when the mis-detection preventing signal is not generated at the circuit (21).