The influence of interconnection of electric power systems on load characteristic and frequency regulation

In China, national interconnected power system is a necessary trend for the development of electric power systems. Due to the time lag and temperature difference in different areas, the peak load discrepancy will influence the ratio of the regular components to stochastic components of system loads when power systems in different areas are connected. The power spectral densities of the regular loads and the stochastic ones were analyzed and compared in this paper, and how the load change works on the frequency regulation was also described with illustrations. The conclusion emphasized that primary frequency regulation is still relatively significant to the security of operating a huge interconnected power system, even if the system frequency could be controlled well through secondary regulation.