Antigen energy function: a new energy function for transient stability assessment

Transient stability analysis using direct methods has gained a lot of importance in recent years. Major two approaches i.e. Liapunov's stability criterion and transient energy function (TEF) has attracted most of the researchers. Non-availability of generalized Liapunov's function and the availability of transient energy function only for low loss system has forced the researchers to test the new function, which can suit the conditions of stressed systems of modern age. In this paper, conceptual antigen energy function is proposed and its usefulness is tested over the multi-machine system. The results are quite comparable with potential energy boundary surfaces (PEBS) and controlling UEP (CU) methods. Antigen energy function gives better estimate of the critical clearing time than PEBS and CU methods, without obtaining unstable equilibrium points (UEP). The development and logical detailing of the function is discussed in this paper.