Technical Parameters_Technical Parameters

±800KV Xiangjiaba——Research on Harmonic Impedance Equivalence of Shanghai UHV DC Transmission Project

According to the planning research results of the Southwest Hydropower Outward Transmission Scheme and combined with relevant foreign research conclusions, ±800KV DC transmission is technically feasible and more suitable for China's actual conditions. Xiangjiaba—Shanghai ±800 UHV DC Transmission Demonstration Project. The converter station access system has complicated boundary conditions. The Jinsha River area power grid has various operating modes. It is possible to reasonably determine the harmonic impedance equivalent parameters for AC filter design. Realize the reasonable configuration of the AC filter scheme and ensure the optimal design of reactive power compensation and control schemes. Therefore, it is necessary to understand the frequency characteristics of the system impedance seen from the AC bus of the converter station to the system, that is, the equivalent harmonic impedance of the converter bus. Commonly used harmonic impedance equivalent tools include ABB's SIMPOW program and Canadian Teshmont's NIMSCAN program. As the NIMSCAN software is similar to the BPA software commonly used in China in the data input format, it has also developed a data conversion and processing interface program, and has successful application experience in the harmonic impedance equivalent of DC engineering converter stations in many countries. ±800KV Xiangjiaba-Shanghai UHV DC transmission project adopts NIMSCAN software to carry out the component parameters of the harmonicator. It is necessary to establish impedance frequency models in the NIMSCAN program, and these parameters are simplified in the routine calculation of the power system. This paper establishes their own impedance frequency models based on the differences in electrical components such as nodes, generators, transformers, lines, etc., and determines the operation mode of the AC/DC system used for harmonic impedance equivalent calculation in Xiangjiaba—Shanghai UHV DC Project. The NIMSCAN program is used to perform the harmonic impedance equivalence and the statistical division of the equivalence results.

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±800KV Xiangjiaba——Research on Harmonic Impedance Equivalence of Shanghai UHV DC Transmission Project

Railway transportation capacity continues to lean towards thermal coal this year

Nuclear power "big cake" attracts many companies competing for food

Local power companies leverage on 920 project to expand in other places

Haoxin Electric Machinery