This paper proposes a fast and efficient strategy to determine the number and locations of fault indicators (FI) in medium voltage distribution networks. The objective function takes into account the most important characteristics of the network such as topology, non-uniform failure rates of the lines as well as the power demand and number of customers. For seeking the minimum of the objective function, a straightforward algorithm based on the Pattern Search (PS) is developed. The methodology is tested on a real distribution network, showing its great potential to improve the reliability indices at the lowest investment costs.

For development and testing of Fault Passage Indicators (FPIs) a laboratory model of a three-phase overhead line has to be constructed. For reasons of current source intensity and space limitations in laboratory conditions, the phase currents and support pole dimensions should be properly scaled in order to achieve same values of magnetic flux density that would appear in normal FPI operating conditions. Scaling laws for calculating the phase currents for different types of faults and various support pole dimensions of the three-phase line model are proposed in this paper. Scaled fault currents and dimensions of the three-phase line model are calculated using the proposed scaling equations and a laboratory model is constructed. The proposed methodology is verified by measurements on the laboratory model.

—The electricity customers may use photovoltaic systems supported by batteries in order to fulfill a fraction of their energy requirements and to decrease the peak demand. The achievable savings primarily depend on a system control strategy. In this paper, one algorithm based on a threshold control is described and tested. The sensitivity on the most important input variables is analyzed by extensive set of numerical simulations.