Distribution system loss minimization using optimal DG mix

In this paper a probabilistic-based model is proposed to determine the optimal mix of different types of renewable distributed generation (DG) units (i.e. wind-based DG and solar DG) to minimize the annual energy losses in the distribution system without violating the system constraints. Beta and Rayleigh probability density functions have been utilized to estimate the random behavior of the solar irradiance and wind speed, respectively; whereas IEEE-RTS system has been applied to describe the load profile. The problem is formulated as a mixed integer non-linear programming (MINLP); with an objective function to minimize the distribution system annual energy losses. This proposed technique has been applied to a typical rural distribution system with different scenarios including all possible combinations of renewable resources. The results show that a significant reduction in the annual energy losses is achieved for all the proposed scenarios.