Study on the Optimization of Renewable Energy LVRT Reactive Power Parameters based on Various Voltage Stability Constraints

With the advancement of intensive development of renewable energy base, the main feature of the power grid at the transmission end becomes the large-scale external transmission of UHVDC with high proportion of renewable energy, the voltage stability of the power grid largely depends on the reactive power support of renewable energy. This paper studies the mechanism of the influence of reactive power output on the AC/DC transmission capacity of the power grid during the low voltage ride-through (LVRT) of renewable energy. According to the constraints of different voltage stability problems, the sensitivity index of the reactive current coefficient on the change of AC/DC transmission capacity during the LVRT of renewable energy is established. Based on this index, the renewable energy stations are clustered. In order to maximize the total AC/DC transmission capacity, a reactive power parameter optimization method during the LVRT of renewable energy is proposed in this paper, which provides decision guidance for the dispatching operation of power grid and improve the economy of the power grid operation, Finally, the effectiveness of this method is verified based on the actual power grid simulation.