Soft starter main circuit adopts thyristor, through changing the thyristor conduction Angle to lift the voltage, to complete the boot process, this is the basic principle of soft starter. High voltage soft starter and the basic principle of low-voltage soft starter, but compared with low-voltage soft starter high voltage soft starter, in some places there is its particularity:

1, High voltage soft starter work under high pressure environment, all kinds of electrical components in the insulation must be better, stronger anti-interference ability of electronic chips. High voltage soft starter of electric cabinet, the layout of the electrical components and other electrical equipment and high voltage soft starter and the connection is also very important.
2, High voltage soft starter must have a high performance control core, to timely and fast signal processing. So the high performance DSP chip, the commonly used control core rather than ordinary MCU core low-voltage soft starter. The main loop of the low-voltage soft starter is composed of three groups of the parallel thyristor. In the high voltage soft starter, because only a single compression capacity of high voltage thyristor is not enough, so must be conducted by the various high voltage thyristor series partial pressure. But each performance parameter of the thyristor is not quite the same. Thyristor parameters are inconsistent, can lead to the thyristor opening time is not consistent, so as to cause the damage of the thyristor.So on the selection of thyristor, thyristor parameters must ensure that each phase as much as possible, and each phase of the thyristor RC filter circuit element parameters as consistent as possible.
3, High voltage soft starter working environment is vulnerable to electromagnetic interference, therefore trigger signal transfer must be safe and reliable. High voltage soft starter, the trigger signals, generally USES the optical fiber transmission, can effectively avoid all kinds of electromagnetic interference. A signal transmitted through optical fiber, also there are two ways: a way of more fiber, a way of single fiber. More fiber way namely to trigger each fiber all the way; Single only along the optical fiber, optical fiber way that each phase signal transmission to a main trigger board, again triggered by the main board to the other of the same phase trigger plate. Because of the various differ in the process of the fiber optical transmission loss and therefore looked from the trigger consistency, single fiber optic fiber more reliable.
4, High voltage soft starter for signal detection than low-voltage soft starter requirements higher. High voltage soft starter the environment where there are a lot of electromagnetic interference, and high voltage soft starter used in vacuum contactor and vacuum circuit breaker in the breaking and closing process produces a large amount of electromagnetic interference. So to detect the signal is not only to hardware filtering, also must carry on the software filtering, get rid of the interference signal.