The principle of the SCR adjustingvoltage circuit and the starting model of soft starter are introduced. The voltageadjusting model SCR is used in this paper.
介绍了晶闸管调压电路的原理以及目前软起动器的起动方式，本文采用晶闸管调压方式。
2
The self-adaptable control of output voltage could be realized under certain range by adding a APFC in ultrasonic generator and adjustingvoltage feedback network with digital potentiometers.
It also introduces the working principle of the SCR adjustingvoltage circuit and the starter's main circuit, the hardware structure and functions of the soft starter and the software program design.