| 摘要 |
PURPOSE:To reduce the amplitude of hunting by providing a first timer where the time is set to an interval for producing average torque smaller than the load torque and a second timer where the time is set to an interval for producing average torque larger than the load torque. CONSTITUTION:A timer 4 is set to time T1 while a timer 5 is set to a timer T2 (where, T2>T1). When the rotary angular speed of rotor is lower than a set angular speed, AND gates 11-16 are opened during the set time T2 of the timer 5 in an interval T0, and transistors Q10, Q20, Q30, Q11, Q21, Q31 are driven through outputs UU, VU, WU, UL, VL, WL. When the rotary angular speed of rotor is higher than the set angular speed, the gates are opened and driven during the set time T1 of the timer 4 in the interval T0. |
