Hi everyone,

I need some help for designing a Soft Start Control Circuit by using microcontroller. The control circuit is used to control the phase angle of thyristor (SCR) in the power circuit.

What microcontroller is suitable for this project?

Thank you for your help in advance.

Hello doinfinity

Welcome to the forum.

While we will not design a soft starter for you by remote control, we ertainly may be able to answer specific questions, or make suggestions.
Is this a private project, student project or a commercial project??

Most microprocessors can be used to make soft starters. The best soft starter is very dependent on what facilities you want to add to the basic voltage controller, and also the processor that you have programming tools for.

Best regards,

Hi marke,

Actually this is a student project.

In the project, the soft starter is used for three phase induction motor. The microcontroller is required to generate gate pulse which used to trigger the six thyristors in the power circuit. By giving the three phase power supply to the microcontroller, then generate gate pulse which is synchronized with the three phase power supply.

Any website or useful material can be found on internet have more information about this topic in detailed.

Your help is much appreciated. Thank you.

Hello doinfinity

I have moved the thread to the students area so that it does not interfere with the more technical discussions in the other area.

I do not know of web sites giving detailed design information on soft starters, but one way of treating them is similar to three light dimmer circuits that are synchronized together. If you can create a phase controlled algorithm on one phase, then you can just add two more that are delayed by the appropriate angles.
At this level it is not very difficult to achieve.

I would probably start with one phase only and control a light bulb to develop the basic SCR control.

Best regards,