Risk-Aware Management of Distributed Energy Resources

High wind energy penetration critically challenges the economic dispatch of current and future power systems. Supply and demand must be balanced at every bus of the grid, while respecting transmission line ratings and accounting for the stochastic nature of renewable energy sources. Aligned to that goal, a network-constrained economic dispatch is developed in this paper. To account for the uncertainty of renewable energy forecasts, wind farm schedules are determined so that they can be delivered over the transmission network with a prescribed probability. Given that the distribution of wind power forecasts is rarely known, and/or uncertainties may yield non-convex feasible sets for the power schedules, a scenario approximation technique using Monte Carlo sampling is pursued. Upon utilizing the structure of the DC optimal power flow (OPF), a distribution-free convex problem formulation is derived whose complexity scales well with the wind forecast sample size. The efficacy of this novel approach is evaluated over the IEEE 30-bus power grid benchmark after including real operation data from seven wind farms.Comment: To appear in Proc. of 18th Intl. Conf. on DSP, Santorini Island, Greece, July 1-3, 201

Innovations in Distributed Energy Resources

The demand for energy is continuously increasing, but the ability to meet it is becoming challenging. Distributed Energy Resources (DERs) will be key players in the future energy mix. This work considers innovations in DERs, and key factors in their developments. This thesis first presents an analysis of the best options for Canada’s involvement in the offshore wind scene. It compared three different scenarios which considered drivers, barriers, support, incentives, and technology advancements. The most favorable scenario is to export Canadian expertise, as the country’s experience in the offshore oil and gas industry can be transferred to offshore wind projects. Installation in Canadian waters is suggested only after developing further understanding of requirements in similar waters. This research also includes the results and analysis of a 1:150 scaled experimental study on the dynamics of a floating offshore platform model under extreme wind conditions. Four configurations were tested under straight wind (ABL), tornado (TLV), and downburst (DB) conditions. It was observed that motions varied greatly when the platforms were subjected to different wind conditions. In general, the TLV and DB flows caused the greatest instability and loosely moored platforms experienced movements of higher magnitude and frequency than tightly moored ones. A major factor in any new project is the financial aspect and business case associated. The final study completed within this thesis is the generation and analysis of a 30-year financial model of a carbon neutral microgrid. Case and location specific factors are considered as well as non-monetary benefits. Ontario-specific policies and incentives are also discussed, and it is determined that presently, they are a major factor in the feasibility of a large microgrid project such as the one presented here

Economic Sizing of Distributed Energy Resources for Reliable Community Microgrids

Community microgrids offer many advantages for power distribution systems. When there is an extreme event happening, distribution systems can be seamlessly partitioned into several community microgrids for uninterrupted supply to the end-users. In order to guarantee the system reliability, distributed energy resources (DERs) should be sized for ensuring generation adequacy to cover unexpected events. This paper presents a comprehensive methodology for DERs selection in community microgrids, and an economic approach to meet the system reliability requirements. Algorithms of discrete time Fourier transform (DTFT) and particle swarm optimization (PSO) are employed to find the optimal solution. Uncertainties of load demand and renewable generation are taken into consideration. As part of the case study, a sensitivity analysis is carried out to show the renewable generation impact on DERs' capacity planning.Comment: 5 pages, 6 figures, 1 table, 2017 IEEE Power & Energy Society General Meeting. arXiv admin note: substantial text overlap with arXiv:1708.0102

Chance-Constrained ADMM Approach for Decentralized Control of Distributed Energy Resources

Distribution systems are undergoing a dramatic transition from a passive circuit that routinely disseminates electric power among downstream nodes to the system with distributed energy resources. The distributed energy resources come in a variety of technologies and typically include photovoltaic (PV) arrays, thermostatically controlled loads, energy storage units. Often these resources are interfaced with the system via inverters that can adjust active and reactive power injections, thus supporting the operational performance of the system. This paper designs a control policy for such inverters using the local power flow measurements. The control actuates active and reactive power injections of the inverter-based distributed energy resources. This strategy is then incorporated into a chance-constrained, decentralized optimal power flow formulation to maintain voltage levels and power flows within their limits and to mitigate the volatility of (PV) resources