JPS5443518A - Start-stop controller for motor - Google Patents

Abstract

PURPOSE: To remove a necessity of using a power feed circuit of big capacity ready for an excessive amount of rush current, by a method of controlling a motor current, when in a starting of the motor, so as to increase from zero to smoothly reach a current of rated value at the time of starting operation.

CONSTITUTION: With a selector switch K closed to a side a of the switch contact a signal of low potential selector circuit 4 is applied to a motor drive signal circuit 10. To the low potential selector circuit 4, are applied two of signals, PI signal and an output signal (difference of signal between a charge voltage of condenser and an output of a current-voltage conversion circuit 7 with respect to the motor current) of slow starting schedule signal circuit 5. Further to the low potential selector circuit 4, is inputted a deviation signal deriving from that a motor current be detected by a detector circuit 6 being converted into a voltage signal by the current-voltage conversion circuit 7 and compared by a comparator circuit 9 with a voltage signal corresponding to a rated current of the motor when in a starting. With a signal of the lowest level of the three of those signal inputs given to the starting schedule signal circuit, a power fed to the motor will be made not to exceed the rating at the time of starting.

COPYRIGHT: (C)1979,JPO&Japio