Suggestions on Triggering of Three Phase Rectifiers

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.