Why asynchronous motors cannot achieve high power

The design and working principles of asynchronous motors and synchronous motors differ, resulting in differences in their power and applicable scenarios.

The working principle of asynchronous motors is based on the principle of electromagnetic induction, which generates torque through the interaction between the rotor and stator magnetic field, causing the motor to rotate.

This design allows asynchronous motors to have higher torque at low speeds, making them suitable for applications that require higher load torque, such as water pumps, fans, etc.

However, as the motor speed increases, the interaction between the rotor and stator magnetic field gradually weakens, leading to a decrease in torque. Asynchronous motors have lower efficiency at high speeds.

In contrast, the working principle of synchronous motors is based on the working principle of DC motors, which generate a magnetic field through excitation current and interact with the rotor magnetic field to generate torque.

The magnetic field strength and torque output of synchronous motors can be controlled by adjusting the excitation current, and synchronous motors have high efficiency and torque output ability at high speeds.
Synchronous motors also have advantages such as compact structure and easy maintenance. In applications that require high power, such as electric locomotives and ship propulsion, synchronous motors are more preferred.