| 摘要 |
<p>PURPOSE:To improve the stability and the efficiency of a motor by composing to suppress a load current to a value equal to and less than the set value. CONSTITUTION:The output of a load current detector 21 is led to a function generator 22. If the load current exceeds the set value, the generator 22 generates an output in response to the deviation. This output is led to a subtractor 23 together with the output of a voltage reference generator 12, and the subtractor 23 outputs as a voltage reference the output which is subtracted by the output of the generator 22 from the generator 12 to a voltage controller 13. As a result, the output of the controller 12 is decreased, the output of a current controller 14 is accordingly reduced, thereby reducing the output of a controllable rectifier 1 to decrease the terminal voltage of a motor. When the terminal voltage of the motor decreases, the primary current, i.e., the load current decreases, and is set to a value equal to and less than the set value.</p> |
