Study on the influence of thermal characteristics of transmission components on overload control of grid-connected lines of wind farms

Abstract

The rapid growth of the installed capacity of wind power is not coordinated with the planning and development of the power grid, which may lead to transmission line overload when N-1 failure occurs in gridconnection lines of large-scale wind power. However, the existing overload protection and stability control strategies cannot adapt to this short-term power flow overload, so a large number of wind turbines need to be removed, which is brought the accommodation problem of large scale cluster wind power. The grid-connection line of wind farms has significant non-synchronization (thermal inertia) between current-carrying and temperature changes, and the short-term current-carrying potential needs to be tapped. This paper summarizes the thermal balance models of two kinds of transmission components and explores the influence of thermal characteristics of transmission components on the overload control of gridconnected lines of wind farms. The simulation results show that considering the thermal inertia of transmission components in overload control can significantly reduce the cut of wind power, fully tap the overload capacity of grid-connection lines.