With the construction of the AC and DC ultra-high voltage hybrid power grid, the external power receiving power from East China Power Grid continues to increase. The characteristics of the large receiving end power grid are very obvious, bringing new challenges to the safe and stable operation of the power grid and emergency accident handling, and also to the dispatch and operation of the power grid. Higher requirements have also been put forward in terms of higher security, better economy and stronger intelligence. A more advanced and intelligent dispatch control system is needed to support the dispatch and operation of the power grid. Especially in the case of power shortages and accidents on high-power AC and DC lines, how to handle emergency disturbances quickly, timely and safely to ensure the rapid recovery of the power grid frequency. It is an important part of the advanced dispatch and control center of East China Power Grid and the world-class dispatch construction.
The "Research and Implementation of Emergency Support Control System for Fault Frequency Recovery of East China Power Grid" project considers the actual operation and future development of East China Power Grid. The impact of high-power cross-regional transmission on the stable operation of East China Power Grid. It studies and analyzes how to efficiently utilize the rotating standby and accident standby of pumping and storage power stations in provincial and municipal control areas under the jurisdiction of East China Power Grid, analyzes the time response characteristics and capacity characteristics of various reserves, and designs the design when a large power loss occurs in the power grid and the power grid frequency is disturbed, A control system that comprehensively coordinates accident backup for power grids and power plants, coordinates the implementation of emergency support, and quickly restores power grid frequency.
Under the existing frequency control system, the East China Power Grid fault frequency recovery emergency support control system comprehensively utilizes the regulation characteristics of two different energy sources, thermal power and pumping storage, adopts intelligent control strategies, and cooperates with provincial and municipal control centers in East China and pumped storage power stations under their jurisdiction. It has jointly built a closed-loop emergency control system with multiple master stations and multiple power stations. The control system includes two parts: the "Regional Control Target Self-Adjustment System" and the "East China Power Grid Pumped Storage Power Station Remote Emergency Support System". When a large disturbance occurs in the power grid frequency caused by the loss of high-power calls, the "Regional Control Target Self-Adjustment System" and the "East China Power Grid Pumped Storage Power Station Remote Emergency Support System" are activated in turn, as the intelligent dispatch technology support of the East China Power Regulation and Control Sub-Center. The emergency accident handling function subsystem in the D5000 system includes monitoring and control of the main station of the East China Power Regulation and Control Sub-center, receiving and controlling dynamic area control errors in four provinces and one city, Tianhuangping under the jurisdiction of East China Power Grid, Group and emergency support control subsystems for the four pumped storage power stations of Tongbai, Xiangshuijian and Langyashan. It involves three links: optimizing the control main station, communication and provincial and municipal (plant and station) control centers, forming a complete closed-loop control system.
The regional control target automatic adjustment and compensation control system is based on the FFC (FTC) directly managed by East China and the AGC control mode of TBC in each province and city. By dynamically correcting the regional control deviation target value, it automatically adjusts the regional control deviation of each province and city to achieve emergency backup sharing and rapid call in provincial and municipal control areas.
The remote emergency support system of the East China Power Grid Pumped Storage Power Station is based on the characteristics of fast regulation speed, wide adjustable range, superior regulation performance, and short-term support system frequency. On the basis of automatic adjustment of regional control targets, remote emergency start and stop of pumping and storage units can be realized by transforming and improving the group control system of pumping and storage power stations.
The commissioning of this system realizes the automatic accelerated recovery of the power grid frequency at the fault frequency for the first time; and makes full use of the characteristics of a single pumped storage unit with large capacity and rapid start-up and shutdown speed, which greatly shortens the power grid's emergency state after a large-capacity power supply is lost. Time, significantly improves the recovery speed, and greatly improves the ability of the power grid to withstand multiple serious faults.
The control system has been successfully applied in the East China Branch of the State Grid Corporation of China, four provinces and one city under the jurisdiction of the East China Power Grid, including Shanghai, Jiangsu, Zhejiang, Anhui and Fujian, and Tianhuangping, Tongbai, Langyashan and Xiangshuijian Pumped Storage Power Stations.