Influence of liberalization Dutch utilities regarding maintenance strategy of protection relays

New law, organisation on commercial bases, competition between utilities brings new challenges for the protection maintenance and development engineer. To reduce maintenance cost is it necessary that maintenance is based on risk management. A good registration of failures or disturbances is necessary to make fundamental decisions. The challenge for asset engineers nowadays is to make a good translation of the maintenance effort to the goals of the utility. To achieve this goal high standards must be put on documentation of the results of maintenance with new analysing techniques and the options of the new numerical relays the engineer has more possibilities to build simple hardware protection systems. To reduce maintenance cost the implementation of modem testing tools and digital protection equipment with reliable self-check functions are necessary.