Effects of damper windings on negative-sequence components under line-to-line fault conditions

This paper examines the effects of damper windings on negative-sequence components appearing in a synchronous generator´s stator and rotor circuits, following an unbalanced disturbance to a one-machine infinite-bus system. The experiment has been conducted on a laboratory power system. The study generator is able to be operated both with damper and without damper. A line-to-line fault has been applied to the system. Both symmetrical component and Fourier analyses are used to investigate measured values of voltages and currents under the faulted conditions. Results will be helpful to understand rarely known behaviors surrounding damper windings