In the context of the question, both technicians A and B are correct:
1. Technician A is correct: Reversing the current flow in a permanent magnet motor will reverse the armature's rotation. This is because the direction of current flow through the armature determines the direction of the magnetic field, which interacts with the fixed magnets in the motor to produce motion. Therefore, reversing the current flow will indeed reverse the rotation of the armature.
2. Technician B is also correct: Voltage supplied to a permanent magnet motor can be pulse width modulated (PWM). PWM is a technique where the voltage supplied to the motor is controlled by varying the duty cycle of a square wave signal. By changing the on-off time ratio of the signal, the average voltage seen by the motor can be adjusted, allowing for control of speed and torque. This modulation can effectively control the speed and direction of the motor.
Therefore, the correct answer is option C: Both A and B. Both technicians are providing accurate statements related to the operation and control of permanent magnet motors.
