The primary distinction between brushless DC (BLDC) motors and brushless AC (BLAC) motors is their back EMF waveform. BLDC motors typically have a trapezoidal back EMF, while BLAC motors (also referred to as permanent magnet synchronous motors, or PMSM) have a sinusoidal back EMF. The shape of a motor’s back EMF is important, because it […]
FAQ: What are the different ways that industry classifies servo motors?
A servo system is one in which the system’s error (in position, speed, or torque) is corrected through the use of a feedback device that compares the system’s actual performance with its commanded performance. What makes a motor a servo motor, then, has less to do with its construction and operation, and more to do […]
What’s the difference between BLDC and synchronous AC motors?
The short answer is: brushless DC (BLDC) and synchronous AC motors are similar in construction and operation. Some manufacturers and experts even group them together as similar technologies, in the category of “permanent magnet synchronous motors.” Their key difference, however, lies in the stator coil windings and resulting back-EMF waveform of each motor. This gives them distinct performance […]