Assessment of circuit parameters by means of genetic algorithms for testing generator circuit-breakers

In order to mitigate the severe prospective transient recovery voltages to values they can cope with, SF6 generator circuit-breakers are usually equipped with capacitors. If these capacitors are not installed during the tests their influence on the prospective transient recovery voltages shall be taken into account and the modified transient recovery voltages applied accordingly. Computer simulations are normally necessary to establish the transient recovery voltages affected by these capacitors. The present papers is specifically concerned with a novel method that uses a genetic algorithm for the calculation of the parameters of complex equivalent circuits in order to represent the specific transient recovery voltage required for a particular generator circuit-breaker application. The parameters of complex equivalent circuits can be chosen to accurately represent the behavior of actual machines such as synchronous generators and step-up transformers. These circuits can be then used to calculate the transient recovery voltages modified by the capacitors of a generator circuit-breaker.