ABSTRACT
In this paper the reliability of the industrial electricity supply is determined by means of Monte-Carlo simulation using two different approaches. In the simplest approach the reliability structure of the network and the components is set up and the system function describes if there is a connection from source to load. This can be easily done by means of a Boolean expression but this approach does not allow to include specific electrotechnical problems. An example, which is considered in the paper, is the reaction of the load to short duration voltage dips. It is known from the literature [1] that the undervoltage protection can disconnect the load after the actual voltage dip has already been terminated. A criterion for this problem of voltage solidity is taken from the literature [1] and is used in simplified form in the paper. For this the voltage at the load after the failure of a component has to be calculated. In this second approach the calculated voltage is compared with the voltage solidity criterion from which it is concluded if the failure leads to plant interruption. The computerprogram needs further development since the voltage solidity criterion has to be refined and since short circuits have to be taken into account.
