Digital simulation for mode identification in thyristor circuits

The paper deals with the digital simulation of thyristor circuits wherein the exact circuit operation is not known. Two methods for digital simulation of thyristor circuits are presented. In the first, a switching device is assumed to be an ideal switch operated by a logic module. The need for automatic formulation of the network equations at the mode changeover points is explained, and it is shown how to achieve this by using suitable forcing functions. This method requires assignment of proper initial conditions at the mode changeover points. In the second method, a switching device is modelled by a binary resistance. In this case, the problem of initial conditions at the mode changeover points is eliminated. These methods are illustrated with an example.