| 摘要 |
PURPOSE:To be able to extremely reduce the ripple of an output signal and to rapidly respond to a load variation by providing a half-wave rectifier, an effective value circuit and a differential amplifier at a filter. CONSTITUTION:A motor voltage V is applied from a voltage oscillator 1 and a motor current I is applied from a current oscillator 2 to a multiplier 3 to obtain a power P. A fullwave rectifier 5 obtains a signal proportional to the absolute value of the motor current I. A differential circuit 4 obtains a signal which represents the difference between a current absolute value proportional signal and a power signal, and smoothes it by a filter 6. The filter 6 comprises positive and negative half-wave rectifiers 6-1, 6-2, effective value circuits 6-2, 6-4, and a differential amplifier 6-5. |
