| 摘要 |
<p>The problem of maintaining precision control of a synchronous motor (12) is solved in a motor start control (10) which utilizes an estimate of the amplitude of the fundamental wave component as a feedback value. The motor (12) receives power from a main inverter (46) and an excitation inverter (48). The inverters (46, 48) are controlled by a control unit (22) which includes a pulse width modulation generator (100) which is responsive to a voltage command (102) and a commutation command (104) to develop switching signals (88) for controlling the switches (S1-S6) in the main inverter (46). At speeds above a preselected minimum speed, the voltage command (102) is developed in a closed loop manner responsive to a feedback signal (116) representing an estimate of the fundamental output of the main inverter (46).</p> |
