What is hysteresis in the context of hysteresis motors?
1 Answer
Hysteresis in the context of hysteresis motors refers to a phenomenon where the rotor (the rotating part) of the motor lags behind the rotating magnetic field generated by the stator (the stationary part) of the motor. This lagging or delay occurs due to the inherent property of certain materials to retain their magnetization even after the external magnetic field has changed.
Hysteresis motors are synchronous motors that operate based on this hysteresis phenomenon. They use a rotor made of a material with high magnetic hysteresis, typically a material like a cobalt steel alloy or certain types of iron alloys. When the motor is powered and the stator generates a rotating magnetic field, the magnetic domains in the rotor material align themselves with the changing magnetic field. However, due to hysteresis, these aligned domains do not instantaneously follow the changes in the magnetic field. Instead, they exhibit a certain amount of "memory" and resist changes.
This lagging of the rotor behind the rotating magnetic field leads to a torque being developed in the motor. This torque causes the rotor to start rotating, and it continues to rotate in synchronism with the rotating magnetic field. Hysteresis motors are known for their smooth and noiseless operation, and they find applications in devices like clocks, record players, and other low-power applications where precise synchronization is important.
In summary, hysteresis in the context of hysteresis motors is the tendency of the rotor to lag behind the changes in the magnetic field due to the magnetic properties of the rotor material. This lagging creates the necessary torque for the motor to start and maintain rotation.
Hysteresis motors are synchronous motors that operate based on this hysteresis phenomenon. They use a rotor made of a material with high magnetic hysteresis, typically a material like a cobalt steel alloy or certain types of iron alloys. When the motor is powered and the stator generates a rotating magnetic field, the magnetic domains in the rotor material align themselves with the changing magnetic field. However, due to hysteresis, these aligned domains do not instantaneously follow the changes in the magnetic field. Instead, they exhibit a certain amount of "memory" and resist changes.
This lagging of the rotor behind the rotating magnetic field leads to a torque being developed in the motor. This torque causes the rotor to start rotating, and it continues to rotate in synchronism with the rotating magnetic field. Hysteresis motors are known for their smooth and noiseless operation, and they find applications in devices like clocks, record players, and other low-power applications where precise synchronization is important.
In summary, hysteresis in the context of hysteresis motors is the tendency of the rotor to lag behind the changes in the magnetic field due to the magnetic properties of the rotor material. This lagging creates the necessary torque for the motor to start and maintain rotation.