DC Emergency Power Support Applied into Frequency Corrective Control

Abstract

The research and application of DC system participating in safety and stability control is still limited to preventive control belonging to the first defense line and emergency control belonging to the second defense line. Exploring and applying the operating characteristics and control capabilities of DC systems is an important technical approach to improve the safety and stability of power grid. DC emergency power support (DCEPS) can be applied into corrective control belong to the third defense line to prevent system collapse coordinating with the traditional third defense line measures such as low-frequency load shedding/high-frequency generator tripping; When an abnormal change of frequency occurs, the DCEPS function is activated to reduce the load shedding/unit control amount. From the two aspects of setting calculation and developing control devices, the preliminary plan for realizing DCEPS to participate in the frequency corrective control is explained. Use the data of the actual power grid to simulate and analyze the beneficial effects of DCEPS participation in the third defense line. Considering the timing characteristics of the third defense line and DC system operation and control characteristics. Discussing the issues that should be paid attention to when DCEPS is applied into the frequency corrective control has important reference value for the construction of the third defense line with richer technical means.