Optimization Methods for Evaluating PV Hosting Capacity of Distribution Circuits

As today’s distribution grid is experiencing increased rooftop solar installations, there is growing interest in evaluating the PV hosting capacity (HC) of the grid. Since, predicting the exact size and location of potential PV installations is not feasible at the distribution grid planning phase, a stochastic method is employed to choose a finite number of combinations of possible PV size and location. As a result, the calculated PV HC is a range of total PV capacity in MW that a circuit can accommodate and not a single value. Additionally, the calculated PV HC range is not unique; it varies with the PV distribution considered for the analysis. This paper proposes an optimal power flow based formulation to find the maximum PV capacity in MW that can be accommodated in a given distribution grid. The PV HC values are evaluated for IEEE 123 bus circuit by the proposed method and the results are compared with the conventional approach. It is observed that the results of the optimal power flow method is unique and can act as the upper bound for the stochastic PV HC analysis.