1. The advantage of direct start direct start is that t […]
1. The advantage of direct start direct start is that there are fewer equipments required, the startup method is simple, and the cost is low. The current that the motor directly starts is about 5 times that of normal operation.
2. The self-coupled transformer is used to step down and start with an autotransformer. The starting current and starting torque of the motor are proportional to the square of the terminal voltage. Under the same starting current, a large starting torque can be obtained.
3. Y-△ step-down starts the motor whose stator winding is △ connected. It is connected to Y when starting, and turns to △ when the speed is close to the rated speed.
4. The rotor string resistance starts the wound-type three-phase asynchronous motor, and the rotor winding is connected to the resistor through the slip ring. The external series resistance is equivalent to an increase in the internal resistance of the rotor winding, which reduces the induced current of the rotor winding.
5. Soft starter Soft starter is a novel motor control device that integrates motor soft start, soft stop, light load energy saving and various protection functions. It is called Soft Starter in foreign countries.
6. Inverter In general, a device that converts alternating current with constant voltage and frequency into alternating voltage with variable voltage or frequency is called “inverter”.