Traveling Wave-Based Differential Protection Applied To Hybrid Transmission Lines With Multiple Sections

This paper presents a performance evaluation of the differential protection function based on traveling waves (TW87) when applied on hybrid lines (HLs) composed by multiple sections. According to TW87 developers, this function can be applied on hybrid lines (formed by overhead lines and underground cables), provided that some restrictions are taken into account. Therefore, to evaluate the performance of the TW87 when applied to multi-section HLs, several faults in a 230 kV/60 Hz power system were simulated using the Alternative Transients Program (ATP). The results reveal that the restrictions proposed by the TW87 developers regarding the length and number of the HL cable sections guarantee the security of the TW87 operation.