REDUCTION OF RING MAIN UNIT FAILURES AND IMPACT ON SAIDI/SAIFI IN TPDDL NETWORK USING THE TQM APPROACH

Abstract

This project explores the application of Total Quality Management (TQM) tools and techniques to reduce Ring Main Unit (RMU) failures within the Tata Power Delhi Distribution Limited (TPDDL) network, and subsequently improve two key electrical distribution reliability indices — SAIDI (System Average Interruption Duration Index) and SAIFI (System Average Interruption Frequency Index). Problem Statement: Frequent RMU failures in various operational zones of TPDDL have contributed significantly to increased customer interruptions and prolonged power outage durations. These failures directly impact the network's SAIDI and SAIFI values, which are critical indicators of power supply reliability and customer satisfaction. The project aims to address the root causes of these failures using structured quality improvement techniques. Objectives: • Identify key technical and procedural causes of RMU failures. • Analyze the relationship between RMU failure frequency and reliability indices. • Apply TQM tools (Pareto Analysis, Ishikawa Diagram, 5 Whys, Control Charts) for root cause identification. • Propose and assess targeted interventions to reduce failure rates and improve reliability. Methodology: The study followed a data-driven research methodology, beginning with the collection of Interruption Data with— including field inspections, SAIDI/SAIFI records, and incident history reports. Using TQM principles, failure trends were analyzed, root causes identified, and corrective measures implemented in a phased manner across selected high-failure RMU clusters. Key Findings: • SF₆ gas leakage, RMU Internal Part Failure, cable joint failure, and relay malfunctioning were identified as the top failure contributors. • Approximately 51% of failures were due to RMU Failure causes, as revealed through Pareto analysis. • Post-intervention data showed a 100% reduction in SAIDI and 100% in SAIFI, indicating improved reliability. • Seasonal and environmental factors, along with procedural gaps, played a significant role in asset underperformance. Future Scope: The study opens up future possibilities for: • IoT-based RMU health monitoring,