A study on the characteristics of TCSC based on digital simulations and physical experiments

The first thyristor controlled series compensation (TCSC) project in China is expected to be applied to the Yimin-Fengtun 500 kV transmission line in the Year 2000 to improve its transmission capability. As a part of the project's feasibility study, this paper focuses on the steady-state and dynamic characteristics of TCSC based on digital simulations and physical experiments. It is necessary to comprehend the characteristics of TCSC devices for modeling TCSC correctly and proposing an effective transient control strategy. The paper studies the following several characteristics of TCSC: the steady-state characteristics in four typical operation modes; the operation symmetry under various control modes; the differences between closed-loop and open-loop impedance control; and the influences of different synchronizing signals on dynamic characteristics of impedance variations.