| 摘要 |
PURPOSE:To prevent the deterioration of torque and overheating by a method wherein the ON/OFF time of winding current is varied in accordance with the fluctuation of a motor driving power source voltage so as to keep the average of the winding current constant. CONSTITUTION:When a power source voltage E1 is increased, the ON-time of a winding current becomes longer compared with the OFF time of the same whereby an average winding current is provided with a tendency to be increased. As a result, an operation to try to reduce the average current and the other operation to try to increase the average current are effected simultaneously whereby the average current is kept constant. On the other hand, when the power source voltage E1 is reduced toward a desired value of the average current is attempted to be increased, only the ON-time is shortened accordingly and, as a result, the average current may be kept constant. |
