Frequency Security and Stability Control Strategy of High Proportion Clean Energy Sending-Out System

With the increasing penetration of renewable energy and the large-scale development of wind, photovoltaic, and pumped storage, it has put forward higher requirements for electricity consumption. To satisfy the demand for power consumption in clean energy-rich areas, large-scale clean energy power is centrally sent out through HVDC transmission. However, the HVDC blocking of a high proportion of clean energy sending-out system will greatly impact the system frequency security, and stability. In this paper, the over/under-frequency protection of the wind turbine and the change of the active power after HVDC blocking are considered. The configuration principle and scheme of over-frequency generator tripping are proposed. A provincial power grid is used to simulate, analyze, and verify the adaptability of different over-frequency generator tripping schemes. The proposed scheme is configured and checked to satisfy the operation requirements of the power grid in case of multiple HVDC sending-out transmissions.