A Single-Pole Filter Assisted Improved Protection Scheme for the TCSC Compensated Transmission Line Connecting Large-Scale Wind Farms

The dynamic variation of impedance during different operating modes of a thyristor-controlled series capacitor (TCSC)-compensated transmission line (CTL) imposes protection challenges to conventionally used distance relays. The problem becomes further complicated when these lines are connected to present-day large-capacity doubly fed induction generator (DFIG)-based wind farms. In this paper, a cutting-edge relaying algorithm is suggested for the protection of such crucial lines by extracting useful features from the local current signals using a single-pole filtering technique. The extracted features are used further to generate Red-Greens-Blue (RGB) images for convolution neural network (CNN) classifier for improved detection and classification of faults. Performance of this method is validated on several fault and non-fault data generated on 2-bus, WSCC 9-bus, and IEEE 39-bus test power systems considering TCSC and DFIG-based wind farm in the network through real-time digital simulator (RTDS). The operation of the actual relay is validated through SEL 451 and the algorithm is accomplished by OPAL-RT (OP5600). The high fault detection accuracy (= 100%, 100%, 100%) and classification accuracy (= 99.30%, 99.50%, 99.20%) and the comparative study can claim the strength of the proposed method.