On-line Condition Monitoring and Diagnosis for Power Transformers Their Bushings, Tap Changer and Insulation System

Utilities need to reduce costs associated to operation and maintenance of installed equipment. Main ways to achieve this cost reduction arc the use of on-line condition monitoring, and a shift from time-based to condition-based maintenance. Thanks to the evolution of monitoring systems, maintenance and operation people can concentrate their activity on other tasks with high added value. Besides these utilities will continue to be faced with daunting challenges due to a deregulated energy market. Increasing loading of equipment, decreasing maintenance expenditures and postponement of investments are goals to reduce life cycle costs. These measures but also can result in higher failure rates and increasing risk of major failures. So the objective is to secure a given quality of supply of electrical energy with minimized cost expenditures for services (life management).