Which method is commonly used for efficient motor starting in high-capacity applications?

The Wye-Delta motor starting method is widely used for efficiently starting high-capacity motors. This technique involves initially connecting the motor in a Wye (Y) configuration, which limits the voltage and current during startup, resulting in a smoother and reduced starting torque. Once the motor reaches a certain speed, typically about 80% of its full speed, the configuration is switched to Delta (Δ), allowing the motor to operate at its full capacity.

This approach significantly reduces the inrush current that is typical with Direct-on-line starting methods, which can be detrimental in high-capacity scenarios due to the large electrical demand placed on the power source. Wye-Delta starting also minimizes mechanical stress on the motor and connected components, prolonging their lifespan and reducing maintenance costs.

While other methods like Soft starters, Direct-on-line starting, and Autotransformer starting have their advantages, they either do not provide the same level of efficiency in high-capacity applications or do not effectively reduce inrush current and torque as Wye-Delta does.