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Synchronous Reluctance Motor vs PMSM vs Induction Motor

Lumsyn Electronic team is committed to the research and development of high-efficiency and high-reliability synchronous reluctance motor drivers, and uses them in air coolers, water pumps and more products.

What is a Synchronous Reluctance Motor?

A synchronous reluctance motor (SynRM) is a special type of synchronous motor that utilizes the uneven magnetic reluctance of its rotor to generate torque. Unlike traditional synchronous motors, the rotor of a SynRM has neither permanent magnets nor windings. Instead, it is constructed of alternating ferromagnetic and non-ferromagnetic materials. This unique structure causes the rotor to experience magnetic forces as it rotates, thereby generating torque.​

SynRM Motor Controller

SynRM Motor & Driver

SynRM Motor Rotor

Rotor of SynRM Motor

​Working Principle of SynRM

  • Reluctance Effect: Magnetic flux always tends to follow the path of least magnetic reluctance. The rotor structure of a SynRM results in varying magnetic reluctance at different positions. When a rotating magnetic field is generated by the stator, the rotor will follow the magnetic field to align itself in the position of minimum magnetic reluctance.

  • Torque Generation: Due to the asymmetric structure of the rotor, an unbalanced magnetic force acts on the rotor during rotation, generating torque that drives the rotor to turn.

 
Advantages of SynRM

  • Simple Structure: The rotor structure is simple, without permanent magnets or windings, resulting in low manufacturing costs.

  • High Reliability: Without permanent magnets, there is no risk of demagnetization, leading to high reliability.

  • High Efficiency: Low rotor losses result in high efficiency.

  • Wide Speed Range: A wide speed range can be achieved.

 
Disadvantages of SynRM

  • Large Torque Ripple: Due to the asymmetric rotor structure, torque ripple is relatively large, requiring special control methods to reduce it.

  • Low Starting Torque: Starting torque is relatively low, necessitating auxiliary starting methods.

 
Applications of SynRM

  • Industrial Drives: Pumps, Air coolers, compressors, etc.

  • Electric Vehicles: As auxiliary drive motors.

  • Home Appliances: Washing machines, air conditioners, etc.

 
Comparison of SynRM with PMSM, Induction Motors
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