Difference between AC Servo Motor and DC Servo Motor

Learn about the key differences between AC and DC Servo motor on the basis of important real-world factors such as efficiency, speed & torque adaptability, size, operational stability, noise, maintenance, and output power.

Power Source is the key difference between AC and DC Servo motors. AC servo motors depend on an AC power source whereas DC Servo motors depend on DC power source (like Batteries).  AC servo motors performance is dependent upon voltage as well as frequency whereas DC servo motors performance mainly relies upon voltage alone. The following table explains the key differences between AC Servo motor and DC Servo motor.

Difference between AC Servo Motor and DC Servo Motor

Characteristics AC Servo MotorDC Servo Motor
EfficiencyLow (about 5-20%)High
Speed & TorqueAdaptable to strong torque and high-sped working condition.Adaptable to a limited torque and speed.
StabilityLess stability issuesMore problems of stability
NoiseNo radio frequency noiseBrushes cause radio frequency noise
OperationHave stable and smooth operationNoisy operation
Weight & SizeLighter weight and small in sizeHeavy weight and large in size
Repair & MaintenanceSince no commutators, Less maintenance is requiredBecause of commutation process, regular maintenance is needed.
Output PowerDeliver low power normally between 0.5W and 100WProvide high power