English title

One of the basic components of future distribution networks are renewable energy resources (RER). The uncertainty in power production of renewable resources such as wind and solar as well as load is another characteristic of such networks. Conventional power flow methods as a basic tool for power system studies may not be suitable for active distribution networks such as microgrids. In this paper a heuristic load flow method considering the effects of intermittent behavior of RERs and load is modeled in probabilistic load flow algorithm. The method is suitable for both radial and weakly meshed distribution networks with RER for operation and planning of microgrids. Imperialist competitive algorithm (ICA) as heuristic based optimization algorithm is applied to formulate and solve the Probabilistic Load Flow (PLF). Based on PLF technique calculated parameters of the system such as bus voltages and feeders' current, are extracted as random variables. A modified version of conventional IEEE 33-bus test system with RER is used as a weakly meshed network to evaluate efficiency and capability of the algorithm. Results are compared with Monte Carlo Simulation (MCS) method. The PDF and CDF of bus voltages, power of feeders' and network total loss are compared. Based on the results the presented approach can solve the PLF problem regardless of the type of distribution network.