The presented work considers some fault distance calculation algorithms in order to check their accuracy for distribution networks when distributed generators are connected and eventually propose solutions. It is motivated by an anticipation of future problems that may occur, resulting from energy market liberalization and changing in the way distribution networks are operated. Preliminary studies had suggested that it would be of use to modify the existing fault distance calculation methods. Our research confirmed this statement and showed that measurements at the connection bus of the DG is the best and the simplest way to account for them. Further we established fault location algorithms that use these measurements to make a simple fault distance calculation method become a fault location one. Specific software based on this algorithm has been developed and tested by many study cases. All kind of faults can be processed and the fault distance accuracy, when the faulted zone is well located, is ranging from -15% to 0%. The faulted zone has been well located in more than 50% of the studied cases.
