Improved adjoint network algorithm for online contingency analyses

An improved adjoint network based algorithm is proposed for static security assessment. The main feature of the algorithm is the calculation of postcontingency nodal voltages and phase angles in a noniterative fashion. This is achieved by adequate modeling of the generator (PV) nodes to account for the voltage regulatorʹs response to line or generator contingencies. The tests show that the improved adjoint network method yields considerable savings in computing time for large power systems while retaining or improving the accuracy of the voltage phasor calculation as compared with the widely used 1P1Q method.