Steady-state Frequency Calculation And Recovery Plan Developing During Load Restoration

The ultimate goal of system restoration after blackout is to restore load fully and rapidly. One of the most important things in load recovery is to control system frequency, and the effective method to keep frequency stability is to control the balance between load recovery speed and generator sets response. Considering the system features in load recovery, system frequency is added to the constraint conditions, which is calculated by expanding Newton-Raphson and expanding PQ algorithms, and the calculation results are compared; sensitivity analysis which can be used to eliminate conditions of overrun in load recovery is proposed, and sensitivity formulae meeting the calculation demands of load recovery are deduced in detail; frequency calculating and genetic simulated annealing algorithms presented in the paper are integrated to develop the best recovery plan, in which the most load is restored and the optimum switch recovery plan is arranged; the proposed method is verified by numerical results on a standard system.