Cost-optimised Maintenance Strategy for 110 kV-Networks Dr Cost-optimised Maintenance Strategy for 110 kV-Networks Dr. Markus Zdrallek RWE Net AG Germany

Optimised maint. strategy Assignment to components Importance of Network Components Optimised maint. strategy 4. Step: Optimised maintenance strategy 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% MA-group 1 MA-group 2 MA-group 3 MA-group 4 MA-group 5 Importance index w i in % Imp. Index & Ranking 3. Step: Importance Index & Ranking Each component is related to the most important component Assignment to components 2. Step: Which part of network’s non-reliability is caused by an individual component ? Reliability Calculation 1. Step: Reliability Calculation Network-, Protection- and Reliability data MV-customers “Energy not delivered in time” Non-reliability of the network

Importance Ranking of Substations 20 40 60 80 100 MA-group 1 MA-group 2 MA-group 3 MA-group 4 MA-group 5 Importance index w i in % Substation

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Importance of Network Components Reliability Calculation 1. Step: Reliability Calculation Network-, Protection- and Reliability data MV-customers “Energy not delivered in time” Non-reliability of the network

Result of Reliablity Calculation 0,0 0,5 1,0 1,5 2,0 2,5 3,0 MV-customers Energy not delivered in time in MVAh/a

Assignment to components Importance of Network Components Reliability Calculation 2. Step: Assignment to components Which part of network’s non-reliability is caused by an individual component ? Assignment to components

Assignment to components 81% 17% 2% 5 10 15 20 25 30 35 40 45 50 Energy not delivered in time in MVAh/a f (E) F (E) Cables / Overhead lines Transformer substations Transformers

Assignment to components Importance of Network Components Reliability Calculation 3. Step: Importance Index & Ranking Each component is related to the most important component Assignment to components Imp. Index & Ranking