PURPOSE:To maintain the system stability at revolution time and prevent revolution at a time of stop by a method wherein simultaneously with speed control gain is increased when the revolution position reaches near the stop instruction position in the control circuit performing the stop position control. CONSTITUTION:Getting the deviation of the instruction value of the speed instruction circuit 101 from the actual speed signal from a speed generator 3 speed control of a DC motor 2 through the speed control circut 1. Also the revolution position of the main shaft 7 driven by said DC motor 2 is detected by a position coder 9 to put its output in a home position stop control circuit 4. The home position stop control circuit 4 is consisted of a loop changing circuit 141, position deviation signal generating circuit 142 and an inposition signal generating circuit 143 and when the revolution position of the main shaft 7 reaches near the stop instruction position, the inposition signal generating circuit 143 generates an inposition signal to raise the gain of the phase compensation circuit 111.
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