Multi‐objective optimal planning of EV charging stations and renewable energy resources for smart microgrids

Abstract

Distribution system planners and operators have increasingly exposed great attention to maximizing the penetration of renewable energy resources (RERs), and electric vehicles (EVs) toward modern microgrids. Accordingly, intensive operational and economic problems are expected in such microgrids. Specifically, the operators need to meet the increased demand for EVs and increase the dependence on RERs. The charging strategy for EVs and the RER penetration level may result in increased power loss, thermal loading, voltage deviation, and overall system cost. To address these concerns, this paper proposed an optimal planning approach for allocating EV charging stations with controllable charging and hybrid RERs within multi-microgrids, where the charging strategy in the proposed planning approach contributed to improving power quality and overall system cost, where the voltage deviation, energy not supplied, total cost have been reduced to 26.03%, 49.57%, and 70.45%, respectively. The simulation results are compared with different optimization techniques to verify the effectiveness of the proposed algorithm. The proposed simultaneous allocation approach of EV charging stations and RERs can reduce operating costs for RERs and conventional stations while increasing the charging stations' capacity.

Modified reptile search algorithm for optimal integration of renewable energy sources in distribution networks

“…}={{CF}\times {U}_{{WT}}\times P}_{{rated}{\rm{\_}}{wind}},$where $${P}_{{rated\_wind}}$$ is the rated produced power of WT, $${U}_{{WT}}$$ and $${U}_{{PV}}$$ represent the WTs and PVs purchased cost ($/kW), and $${P}_{{Wind}(h)}$$ and $${P}_{{PV}(h)}$$ represent the yielded power from WTs and PVs systems. $$${CF}=\frac{\beta \times {(1+\beta )}^{{NP}}}{{(1+\beta )}^{{NP}}-1},$$$where $$\beta $$ and $${NP}$$ the interest rate and system lifetime of the winds turbine or PV unit 36 …”

“…To improve the network performance, the voltage deviations should be kept closed to 1 p.u. value which can be defined as 36,39 $$$\sum {VD}=\sum _{h=1}^{24}\sum _{k=1}^{{NB}}|({V}_{k}-1)|,$$$where $${NB}$$ represents the number of buses in the network, and $${V}_{k}$$ represents the voltage of the k th bus.…”

“…where β and NP the interest rate and system lifetime of the winds turbine or PV unit. 36 The generated power from the PV can be calculated as follows:…”

“…To improve the network performance, the voltage deviations should be kept closed to 1 p.u. value which can be defined as 36,39…”

Optimal Operation of Distribution Networks Considering Renewable Energy Sources Integration and Demand Side Response

“…To ensure that the power grid operates efficiently and reliably, the voltage deviations should be maintained within an allowable range, ideally close to 1 p.u. The definition of the overall voltage deviation is [34,35]:…”