What are the starting modes of induction motors?

Starting mode of asynchronous motor

1.1 soft start

With the rapid development of microcomputer control technology, has successfully developed a number of electronic soft starting controller in control engineering field, is widely used in the starting process of the motor, the step-down starter will be replaced. Use the soft starting current electronic facilities are voltage circuit, thyristor regulating circuit, which is composed of the following description: thyristor six, 22 anti parallel connected to a three-phase power supply, the system sends the start signal, the microcomputer control system to calculate starter immediately, make the thyristor trigger delivery signal, the turn-on angle of thyristor control, according to the given output, adjust the output voltage, the motor control. The starting mode is suitable for three-phase AC asynchronous motors with various power values, including the starting control of six and three connection modes.

1.2 direct start

This is the most simple way of starting the most basic way of starting motor, with the help of the first electric motors and are connected with a knife switch, the rated voltage of motor starting up and running, the features are: less investment, simple equipment, small number, although the starting time is short, but the torque is small, the starting current larger, more suitable for application in small capacity motor starting.

1.3 step-down starting

Because of the disadvantages of direct starting, the step-down start occurs. For starting this starting environment for no load and light load of the two cases, the starting mode is also realized in step-down starting torque and starting current, so the starting after the end of the work needed to make the circuit back to the rated state.