Damping of current oscillation in superconductive line applied for high voltage direct current transmission system

The application of a superconductive transmission line to a high-voltage direct-current transmission system is considered. However, unstable phenomena similar to an AC system are introduced. The authors suggest installing a damper circuit, which consists of an inductor and a resistor in parallel, to prevent such instabilities. In a steady state, most of the DC current flows into the damper inductor and generates little loss, but once oscillation in the DC current is induced, voltage appears across the damper inductor, and the resistor generates the loss for the current. The loss dissipates the energy of the oscillation and damps it. The effectiveness of proposed damper circuit was shown by using computer simulation.<>