Second-kind energy function of power system and its applications

This paper presents a second-kind energy functions for power systems. The previously introduced complex integral approach yields two kinds of energy integral expressions for its real and imaginary parts. The former provides a second-kind energy function while the latter the conventional energy function. It has been shown that a series of energy functions can be generated by taking the weighted sum of the conventional energy function and the second-kind one. By taking appropriate weights, a well-defined energy function can be derived to reflect the transfer conductances when the system has uniform R/X ratios for all transmission lines with separation of generator reactances.