I am constructing a dynamic model (using ordinary differential equations) of Three Phase Fully Controlled Unidirectional Rectifier. And I am facing problems regarding the triggering logic of Thyristors. I would like to know if anyone can give any suggestions regarding various methods available for the triggering logic of thyristors (especially for the dynamic model). Any help would be greatly appreciated.
Thanks in advance.
Triggering can be provided with pulse generator in matlab
Or
Generate triggering pulse by comparing triangular wave and DC
I think waveshape would be sawtooth with falling edge at zero crossing. A phasing transformer could be used to generate power supply and provide phasing information for real world iof you plan to go that far.
You could trigger them with the pulse generator. It's important you trigger the correct sequence of the thyristors. For example if you have a three phase system with 0, -120 and -240 degrees you have to trigger in this sequence to obtain the same behavior as diode bridges (first the top left one, second the right bottom, then the top middle, then the left bottom, then the top right and last the bottom middle). The times you trigger them you should calculate based on the times the sine waves of two phases match in one point. If you accomplish this, you can add different delays to the whole bridge to control the DC link
Depending on software you used, I think , you should generated the logical signals. First you should detect voltage crossing (natural commutation) point for each pair of phases and then after previously defined time generate (delay) trigger signals. Comparing triangular and DC waves is more complicated in logical domain, but possible. If you give some details about the software, function input type, maybe I will be able to find ready to use solution.
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