Improved Risk Matrix for Distribution Transformer in East Java: Analytic Network Process and Modified Total Ownership Cost

Abstract

Many studies have been conducted on risk assessment in distribution transformers. However, previous studies have not fully considered the risk analysis and cost impact of damage to distribution transformers. In addition, the use of the Modified Total Ownership Cost Method is one comprehensive approach to calculating the cost implications of damage to distribution transformers. The use of risk matrix to determine likelihood factors and consequence factors still does not consider several factors, and the factors used often have equal weight and are interrelated. This study collects all the indicators used for probability and consequence factors in the risk matrix and applies the Analysis Network Process to give weight to those factors. The result is a more accurate risk evaluation model, supporting decision-making regarding investment in distribution transformers in East Java. A modified and weighted risk matrix was applied to 65 distribution transformers, of which 3 had low risk, 14 had moderate risk, 38 had high risk, 8 had very high risk, and 2 had extreme risk.