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 […]
Search Results for: difference between bldc and synchronous ac motors
Motion Trends: New motor breeds are smart, connected, and compact
This year’s survey of trends in electric motors for motion control and automation revealed several trends and emerging developments in the use of synchronous ac motors; stepper motors, especially in closed-loop offerings; brushless motors of various types; and a smattering of specialty direct-drive offerings just making inroads. Proliferation of synchronous ac motors With construction and […]
Which types of DC motors can be used as servo motors? (And a refresher on DC motor technologies)
Servo motors are used in applications where precise control of position, speed, or torque is required. But many different types of motors can be considered servo motors — the defining feature of a servo motor is that it incorporates or reads feedback in a closed-loop system. In fact, although many servo applications use synchronous AC motors, […]
Motion technologies and software for next-generation eBikes
Since their emergence in the early 1990s, eBikes have undergone a steady series of improvements in range, reliability, and performance that have won them a growing number of loyal users worldwide. Equipped with specially engineered frames, high-capacity Li-Ion batteries, and highly efficient drive control electronics, today’s eBikes have become a low-carbon option to cars for […]
What’s the difference between an EC motor and a BLDC motor?
Deciphering motor terminology can be frustrating, especially when comparing the operation and performance of various motor types. For example, some motors are characterized by their speed (synchronous or asynchronous) while others are characterized by their commutation method (brushed or brushless). And then there’s the issue of whether the motor is operated with AC or DC […]
What’s the difference between cogging torque and torque ripple?
The basic operation of an electric motor relies on the interaction between the rotor’s permanent magnets and the stator’s energized windings. But even when the motor is not powered and no current is flowing though the windings, there is a magnetic attraction between the permanent magnets of the rotor and the ferromagnetic teeth of the […]
Selecting a servo drive: 9 things you need to know
Sizing a motor for a servo application requires evaluating the move profile and torque requirements to determine the mechanical demands of the system, such as maximum velocity and acceleration, RMS and peak torque values, and load-to-motor inertia match. Once the motor is chosen, the next step is to select a drive. On the surface, selecting […]
BLDC motor: Marketing jargon or more?
The term brushless dc motor (or BLDC motor) is common lingo in the industrial world. The question is, does it make any sense? Perhaps a little history can help here. The first brushless dc motors were marketed as such because they functioned as drop-in replacements for brush dc motors. There were a number of technological […]
Trends in electric motors part one: Market shifts towards smart solutions
This year in motor design there’s been an uptick in three trends. Disposable medical devices, new consumer products, and the automation of humbler tasks are driving demand for affordable and miniature-motor options. (Read more about motor miniaturization in the second installment of this two-part Motion Trends series on electric motors here.) A related trend towards […]
FAQ: What are ways to avoid torque ripple in DC motors?
Torque ripple—variations in torque production during shaft revolution—is an undesirable effect that occurs in permanent magnet motors, preventing smooth motor rotation. Torque ripple is generally defined as non-linear torque production of an energized motor. Cogging torque—a phenomenon similar to torque ripple—is torque produced by the attraction between the permanent magnets of the rotor and the […]