Optimized Distance Protection Scheme for AC Transmission Lines Based on Phase Angle Difference of New Energy Equivalent Source

This paper discusses the adaptability of positive-sequence voltage polarized phase-comparison distance protection in renewable energy integration scenarios and proposes an optimization scheme. In the voltage plane, the analysis indicates that an increased phase angle difference between the internal electromotive force (EMF) of renewable energy sources and the positivesequence voltage measured by the protection device may lead to incorrect operation of the distance protection. Using the port equivalent method, the position of the internal EMF of renewable energy sources under different fault types is calculated and analyzed, leading to conclusions regarding the adaptability of distance protection. The study finds that the performance of distance protection remains largely unaffected during…