TCR and SR compensators in composite electromagnetic transient simulation

Following the recent development of a detailed, electromagnetic transient model for saturated reactor (SR) compensators, the present paper is devoted to companion investigations related to the alternative form of compensators based on thyristor-controlled reactors (TCRs). A model is developed for TCR compensators which provides a similar degree of detail in representation to that of the earlier SR compensator model and is of equal rigour in its derivation. It makes comprehensive provision for representing TCR compensators of any given pulse-order, control-objective function and control-system design in a very wide range of studies related to transient modes of operation. Drawing on established z-plane methods of numerical electromagnetic transient analysis in power-network systems, a unified formulation is achieved, which combines the nonlinear elements of SR models with the time-varying branches by which thyristor switching in TCR compensators is represented. Representative study results are given for a section of a transmission system which includes both SR and TCR compensators at the one control location, so that one complements the other.<>