The Stability of Hybrid Simulation of Power System

Hybrid simulation is important to the modern power systems which include high frequency components such as HVDC or FACTS with switching processes. Full digital model has its limit on its finite simulating frequency due to its discreteness, as a result , it´s not available to describe the high frequency responses accurately and a more efficient simulating method-the digital-analog hybrid model comes into being, which´s based on circuit substitution theorem. An interfacing method via node overlap is presented in this paper: the node voltage variable from interface point is outputted through D/A channel to form analog Thevenin source branch, meanwhile, the digital Norton source of interface branch is formed from the branch current variable inputted via A/D channel. Then the discriminate of model stabilization is deduced, based on which the hybrid model is proved to be conditional numerical stable system. Finally the digital-analog model interfacing experiments for verification is performed.