RAPID CALCULATION OF THE PERIODIC STEADY-STATE FOR ELECTRONICALLY SWITCHED, TIME-VARYING POWER-SYSTEM LOADS

The periodic steady state of power distribution system loads is studie d for the electronically switched, time varying cases. Many loads of t his type appear on contemporary power systems as energy saving and con trollable demands. Several alternative methods of calculating the peri odic steady state are discussed and new method is proposed based on th e frequency modulation property of the discrete Fourier transform. The new method is termed the gain-shift formula (GSF) because the format of the technique entails adding frequency shifted terms which represen t the parameter to be calculated. An example of a triac switched load on the distribution system is given. The main advantages of the GSF ar e: rapid calculation of the periodic steady state and efficient calcul ation of the frequency spectrum of voltages and currents in the period ic steady state.