Electrical installation dependability studies

Methodology and tools

In both the industrial and tertiary sectors, the quality of power supply is of increasing importance. The quality of the electricity product, besides imperfections such as variations in voltage and harmonic distortion, is basically characterised by the availability of the electrical energy.

Loss of power is always annoying, but it can be particularly penalising for information systems (computing – monitoring and control); they can even have disastrous consequences for certain processes and in certain cases endanger people’s lives. Dependability studies enable electrical availability requirements to be incorporated in the choice of electrical network to be installed. They also enable two different installation configurations to be compared … the most expensive one is not always better …

The aim of this «Cahier Technique» is show how dependability studies are performed: methodology and tools. Two examples of studies are given: that of an electrical network in a factory and that of the monitoring and control system of a high voltage substation. These studies are becoming increasingly easy to perform thanks to computing «tools».

General

The voltage at the terminals of a current consumer can be affected by phenomena originating in the distributor’s network, the electrical installation of a subscriber connected to that network or the electrical installation of the user who is suffering the disturbance.

AUTHOR: Schneider Electric expert | Sylvie LOGIACO