Primary frequency control characteristic of a grid

In power system, primary frequency control (PFC) is one of the important methods to maintain frequency stability. But, setting large dead band or illogically adding PFC into power system in digital electro-hydraulic (DEH) system weaken the ability of primary frequency control, that results in grid frequency stability decrease against sudden accidents. Based on the Southern Hebei Grid accident investigation, the mathematical model of Southern Hebei Grid is established in this study for analysis of primary frequency control. The relationship among parameters which affect PFC ability such as dead band, load disturbance and PFC capacity were discussed. This study can help to set the parameters of governing system and the PFC capacity of the Southern Hebei Grid.