The Analysis of Strategies for Large Thermal Power Unit Frequency Control after the Breakdown of Isolated Network in Sending-End Network

Abstract:

As for the hidden dangers of low-frequency load shedding caused by high frequency generator tripping in isolated power grid because of the failure connection between outward transmission district grid and leadership grid, we gave an analysis to problems with high-frequency in sending network and isolated power grid, and reasons causing the unmatching between OPC and governors. Then, we adopted the measured parameters of thermal power units for the analysis of its regulating system under the isolated power grid, and discussed the regulating effect when the lower amplitude of the primary frequency was-30% and full liberalization. As for the high rate of load shedding in the sending network, this paper has put forward an optimization strategy for thermal power unit frequency control in isolated network. Release primary frequency amplitude to-30% in isolated network, measure the acceleration of rotation speed when OPC acts at the first time, calculate the tragic power of the unit and send it to AGC system. The unit quickly adjusts the power of the unit according to new AGC instruction, and stabilizes the frequency in isolated network. This strategy can help to realize the coordination between OPC and speed governor, and improve the margin of high-frequency in isolated network.

• Periodical: Applied Mechanics and Materials (Volume 392)
• Pages: 646-650
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.392.646
• Online since: September 2013
• Authors: Hao Wang, Qing Wang, He Huang, Yong Zhang, Yun Ting Song, Jian She Tian
• Keywords: High-Frequency, Isolated Grid, Small Power System Containing High Capacity Generator, Water-Turbine Generator, Wide-Area Measurement System (WAMS)

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