Initial value calculation for dynamic simulation of power systems in the presence of disturbances within transmission network

Transient stability analysis of power systems involves the study of synchronism (through dynamic simulation) when the system is subjected to large disturbances within the transmission network, such as: load switching, loss of generators, loss of lines, or short circuit faults. One major problem in the above simulation is finding the initial values of the algebraic state variables involved in the simulation. This problem is, basically, a modified power flow problem that involves calculation of bus voltages and angles for all buses including the generator and the swing buses. Although the available industrial simulation packages solve the above mentioned problem, but the method of solution has not been reported in the open literature. This paper presents an approach to solve the above initial-value calculation problem by modifying the existing power flow program. The presented approach is applied/tested on the IEEE 14-Bus test system using MATLAB.