Asset Wellness Calculation Method of 150 - 500 KV Oil Immersed Power Transformer Using Combination of Technical Diagnostic and Risk Assessment

Asset Wellness Calculation represents a method that combines technical diagnostic with risk assessment into an objective and quantitative value, providing the overall wellness of the asset. In this paper Asset Wellness calculation method of 150-500 KV oil immersed power transformers located in tropic region were discussed. The Asset Wellness method uses various data, not only data from technical test results such as dissolved gas analysis, electric testing, but other important data such as transformer loading data, maintenance data, age, grounding and foundation. The asset wellness method uses the IEEE, IEC, CIGRE criteria limits and limits on diagnostic tools for determining conditions. The Asset Wellness method is a combination of technical conditions with risk assessment based on the weight and criticality criteria of the equipment on the transformers which in total value will determine the health condition of the transformers. The method used in determining the criticality level of transformer equipment uses the SERP (System and Equipment Reliability Prioritization) method developed by EPRI. This method uses an approach based on technical data based on the level of criticality of the equipment combined with an assessment of the level of risk of down time. The Asset Wellness method is one of the tools in managing quantitative assets to determine the condition of the transformer and allows recommendations for the maintenance strategy of asset.