Three-phase optimal power flow based distribution locational marginal pricing and associated price stability

Most of the ongoing smart grid projects are focused on power distribution system automation and upgrades. Although there is no electricity market in the distribution system yet, this will be a natural step with increasing penetration of distributed energy resources (DER). This work extends transmission locational marginal price (LMP) concept to distribution level. A new Optimal Power Flow (OPF) methodology based on Three-phase Current Injection Method (TCIM) is proposed in this paper to compute distribution locational margin price (DLMP). The proposed OPF method is used to compute LMP for three-phase unbalanced distribution system. The computed DLMP is used for price stability computation utilizing Generalized Autoregressive Conditional Heteroskedastic (GARCH). The case study is implemented with a modified IEEE 13-bus system. The results demonstrate the satisfactory performance of the developed OPF based DLMP algorithm and allows for the evaluation of the price stability of the system. Indicating the level of price stability can enable electric market participants and operators to make informed decisions.