Servo motor controller enables sensorless operation of BLDC motors

The 4-quadrant PWM servo motor controller offers efficient control of permanent-magnet activated sensorless BLDC motors without Hall sensors up to approximately 200W. Maxon says its drift-free yet dynamic speed behaviour enable speeds up to 120'000rpm and provides extensive functionality with free configurable digital and analogue inputs/outputs. The servo controller is controlled by an analogue set value. It can be specified by means of analogue voltage, by external or internal potentiometer, by defined value, or by means of a PWM signal with variable duty cycle. Other features include the ability to enable or disable the power stage depending on the direction of rotation, as well as sensorless acceleration and deceleration by employment of defined speed ramps. The unit has been designed specifically with easy start-up and user-friendliness in mind. It features protective circuitry against overcurrent, excess temperature, undervoltage and overvoltage, voltage transients and short-circuits in the motor cable. It also is equipped with protected digital inputs and outputs and adjustable current limitation to protect motor and load.