| 摘要 |
<p>A control circuit for a brushless d.c. motor (11) providing positive control whatever the polarities of motor voltage and motor current. The circuit provides control of motor current, thereby controlling motor torque, in response to an applied current command signal, relying solely on feedback signals of motor current (41) and rotor angle (36). The heart of the system is a level dependent logic stage (34) which selectively controls the states of the switches (40) applying power to the motor windings in accordance with a current error signal (le) developed by reference to the feedback current signal. The control circuit causes the motor current to correspond to an applied current command and works at any motor speed and torque for rotation in either direction.</p><p>In a preferred embodiment, the basic control system is combined with additional feedback loops (22,14) developing servo information regarding rate and actuator position to provide an overall position control system, such as is particularly useful in place of the hydraulic actuator systems now employed in aircraft.</p> |
