Frequency deviation peak calculation of sending-end network in large asynchronous interconnected power grid

Abstract

The asynchronous connection by high-voltage direct current (HVDC) links optimises the power angle stability of the large area power grid. However on the side of the sending-end, the loss of DC links causes high frequency, of which the frequency deviation peak is an important index in the study of the power grid frequency stability. In this study, the method to calculate the peak value of frequency deviation based on the change rate of the frequency deviation is obtained by analysing a single-machine system. Then, the application of method is extended to the actual power system to study HVDC additional control and generator tripping. Finally, the single-machine power grid and Yunnan Power Grid are simulated, respectively, to verify the accuracy and the feasibility of the method. The simulation results show that the method is accurate and applicable to the actual power grid, which has practical value of engineering.