Study on Coordinated Control of New Energy Over-Frequency Ride-Through and Over-Frequency Generator-Tripping Scheme

Abstract

After the fault isolation of the outgoing power grid with a high proportion of new energy, the high-frequency shutdown of the third line of defense is an important control measure to restrain the rise of the frequency of the sending-end power grid. With the increase in the proportion of intermittent power sources such as wind power and photo-voltaic power, the frequency characteristics of the power grid have become more complex. Considering the response characteristics and emergency control capabilities of wind power and photo-voltaic power, this paper proposes a high-frequency ride-through control strategy based on new energy stations. Through coordinated control with high-frequency shutdown measures, the new energy stations can rapidly reduce their power to replace some costly conventional unit operations to achieve more economical frequency safety control, after the high-frequency machine switching round action is executed to avoid over-switching triggering low cycle load shedding when the frequency is reduced to the threshold value, it will trigger the rapid recovery of new energy power generation to meet the requirements of refined frequency stability control of modern power grids. Based on the actual planning of the high-voltage transmission end grid scale, a simulation system was built, and a new energy high-frequency ride-through model was built, which verified the feasibility of the proposed coordinated control scheme for high-frequency switching off with a high-frequency ride-through, and verified the adaptability of the proposed scheme under different operation modes.