| 摘要 |
PROBLEM TO BE SOLVED: To enable stable speed control in a high-speed operation region, wherein a shunt DC motor is used, the armature voltage is made constant, and reducing magnetic field control is performed. SOLUTION: An armature voltage command value Vac is transformed from a speed command value Ns, according to a specified functional relation and inputted in an armature voltage adjuster 2, which outputs an armature current command value Iac. This value is inputted in a high-speed operation region, where the armature voltage is constant and magnetic field reducing control is performed. An armature current-limiting circuit 3 commands the upper limit value IaL of an armature current, irrespective of the speed command value Ns in the high-speed operation region. An Ifc-correcting circuit 6 calculates the deviation (Iac-IaL) between both of the command values and performs transformation operation of addition correction value to a field current command value Ifc transformed from the speed command value Ns, according to a specified functional relation. The filed reducing control in the high-speed operation region is inverted to field increasing control by the addition correction to the field current command value. Thereby decrease in armature output torque is excluded, and speed control in the high-speed operation region is stabilized. |
