ANALYSIS OF ACCURACY IMPROVEMENT IN ADAPTIVE AUTORECLOSE BASED ON TRAVELING WAVE IN HYBRID TRANSMISSION LINES

• Main Author: Iswara Alison, Johan
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/87423
• Institution: Institut Teknologi Bandung

The 150 kV South Sumatra-Muntok hybrid transmission interconnection system utilizes a combination of various transmission media, including 25.7 km of overhead transmission lines, 3.937 km of underground cables, and 36.1 km of submarine cables. With a total length of 65.76 km, the system adopts an adaptive auto-reclose protection system that relies on the Traveling wave Fault Location (TWFL) method, integrated with the 87L line current differential relay. The autoreclose function is disabled when faults occur in the underground/submarine cable (USC/UGC) segments due to the high likelihood of permanent faults that damage the cable’s insulation layer. In contrast, most faults in the Overhead Line (OHL) segments are transient, and thus, the auto-reclose function is only activated in the OHL segments. This thesis explores methods to enhance the accuracy of TWFL in fault location determination through the analysis of operational data and switching events. The study emphasizes that the system’s accuracy is highly dependent on the protection relay’s response speed and the optimization of the traveling wave line propagation time (TWLPT) and traveling wave cable propagation time (TWCPT) settings. The results indicate that by recalibrating the TWLPT and TWCPT to 344.5 ?s and 3.048 ?s, respectively, the fault distance reading error can be reduced to 0.085%, or approximately ±56 meters. This suggests that a fine-tuning analysis based on operational data can significantly improve the precision of fault locators, reducing the error rate from 11.81% to 0.085%.