Liu Mingzhong

Research on the filed commissioning test method for phase selection making control device

The U/EHVDC technology plays an important rule for transmitting from West to East in China. In order to improve the reliability of electrical equipments in Ultra High Voltage Direct Current (UHVDC) transmission project, and standardize the filed test method, the field commissioning test technology of phase selection making control device is studied combining Xiangshang ±800kV UHVDC transmission project. From the principle of work of phase selection making control device, according to the pre-breakdown features and impact of environmental temperature and control voltage, the closing time model of typical breaker applied to the detection for phase selection making control device is established, and the method for filed commissioning test is proposed. At last, the filed commissioning test technology is applied in Fulong converter station, the testing results show that it could find and eliminate the equipment deficiency timely, which verify its feasibility and validity.

Adjusting for the unblance of capacitor banks with H-bridge connection of power filter on UHVDC converter station

A method for adjusting the unbalance of the capacitor banks with H-bridge connection of the power filter on UHVDC converter station in this paper. Firstly, the concept of unbalance degree is proposed, and the expression of the unbalance degree is deduced, then the new method for adjusting the unbalance of the capacitor bank with H-bridge connection is put forward. The detection method is adopted to detect and adjust the unbalance of the capacitor with H-bridge connection. The test result shows that the proposed method could improve the work efficiency greatly, and the method is suitable for field commissioning test in UHVDC converter station.