synchronous motor
C1Technical / Engineering
Definition
Meaning
An electric motor whose rotor rotates at the same speed as the rotating magnetic field produced by the stator.
A precise AC motor used where exact speed control is critical; it maintains constant speed regardless of load variations, making it essential for applications like clocks, timers, and industrial machinery requiring synchronization.
Linguistics
Semantic Notes
The term emphasizes synchronization with the power supply frequency; distinct from induction motors which slip.
Dialectal Variation
British vs American Usage
Differences
No significant lexical differences; concept is identical in both engineering communities.
Connotations
Precision, timing, industrial control.
Frequency
Equally common in technical contexts in both regions.
Vocabulary
Collocations
Grammar
Valency Patterns
The [device] uses/incorporates a synchronous motor.A synchronous motor is employed for [purpose].[Application] requires/relies on a synchronous motor.Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “In sync like a synchronous motor”
- “Running like a well-timed synchronous motor”
Usage
Context Usage
Business
Rare, except in procurement contexts for industrial equipment.
Academic
Common in electrical engineering and physics texts discussing motor principles.
Everyday
Virtually never used; average person would say 'electric motor' or 'motor'.
Technical
Standard term in engineering, automation, and industrial design documentation.
Examples
By Part of Speech
verb
British English
- The system is designed to synchronously motor the conveyor belt.
American English
- The controller will synchronously motor the assembly line.
adverb
British English
- The fans run synchronously, powered by identical motors.
American English
- The pumps operate synchronously to maintain pressure.
adjective
British English
- The synchronous-motor drive is more efficient for this application.
American English
- We need a synchronous-motor controller for the timing mechanism.
Examples
By CEFR Level
- This clock has a small motor inside.
- Some factory machines use a special motor that keeps perfect time.
- For precise speed control, engineers often select a synchronous motor over an induction type.
- The hysteresis synchronous motor provides exceptional speed regulation and is ideal for instrumentation drives.
Learning
Memory Aids
Mnemonic
Think 'synch' as in 'synchronize' + 'motor' – a motor that stays perfectly in sync with the power current's rhythm.
Conceptual Metaphor
A disciplined dancer precisely matching the tempo of the music, never missing a beat.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid literal translation; Russian equivalent is 'синхронный двигатель', which is a direct calque but used in highly technical contexts only.
- Do not confuse with 'синхронный мотор' (less common but acceptable technical variant).
Common Mistakes
- Pronouncing 'synchronous' as /saɪnˈkrəʊ.nəs/ (incorrect stress).
- Confusing with 'servo motor' (which is about positional control, not necessarily speed synchronization).
- Using 'synchronous motor' in everyday conversation instead of simply 'motor'.
Practice
Quiz
What is the primary characteristic of a synchronous motor?
FAQ
Frequently Asked Questions
No, most traditional synchronous motors are not self-starting and require an auxiliary method (like an induction winding or separate starter motor) to bring them near synchronous speed before they can 'lock in'.
In applications requiring exact constant speed: electric clocks, timers, tape drives, recording equipment, gyroscopes, and large industrial drives like compressors and generators.
A synchronous motor's rotor rotates exactly at the supply frequency's synchronous speed, while an induction motor's rotor always rotates slightly slower (slips) than the magnetic field, which is necessary for it to produce torque.
Yes, electronically commutated brushless DC motors (BLDC) are functionally a type of permanent magnet synchronous motor (PMSM), where the controller provides the rotating magnetic field synchronously with the rotor position.