Optimal Day-ahead Scheduling of Islanded Microgrid Considering Risk-based Reserve Decision

Abstract

Due to the lack of support from the main grid, the intermittency of renewable energy sources (RESs) and the fluctuation of load will derive uncertainties to the operation of islanded microgrids (IMGs). It is crucial to allocate appropriate reserve capacity for the economic and reliable operation of IMGs. With the high penetration of RESs, it faces both economic and environmental challenges if we only use spinning reserve for reserve support. To solve these problems, a multi-type reserve scheme for IMGs is proposed according to different operation characteristics of generation, load, and storage. The operation risk due to reserve shortage is modeled by the conditional value-at-risk (CVaR) method. The correlation of input variables is considered for the forecasting error modeling of RES and load, and Latin hypercube sampling (LHS) is adopted to generate the random scenarios of the forecasting error, so as to avoid the dimension disaster caused by conventional large-scale scenario sampling approaches. Furthermore, an optimal day-ahead scheduling model of joint energy and reserve considering riskbased reserve decision is established to coordinate the security and economy of the operation of IMGs. Finally, the comparison of numerical results of different schemes demonstrate the rationality and effectiveness of the proposed scheme and model. Index Terms--Day-ahead scheduling, risk-based reserve decision, conditional value-at-risk (CVaR), renewable energy source (RES), islanded microgrids.

Stochastic Generation Scheduling of Insular Grids with High Penetration of Photovoltaic and Battery Energy Storage Systems: South Andaman Island Case Study

“…Constraints in (11) to ( 13) are associated with start-up costs. First stage start-up constraints and second stage start-up constraints are presented in (11) and (12).…”

“…Since the start-up constraints are temporal constraints, commitment status at the time, t, (u it , v itω ), and commitment status at (t − 1), (u i,t−1 , v i,t−1,ω ), are considered in (11) and (12). A non-anticipatory constraint connects the first-and second-stage start-up variables in (13).…”

“…Researchers have addressed the RES intermittency issue in two ways: either by enhancing the forecast qualities through different prediction models [10] or by optimal management of the generation scheduling problem in such a manner that the impact of variable output from RES is accommodated [11]. The latter approach is achieved by appropriate mathematical formulations that incorporate the constraints that can deal with volatility associated with RES.…”

An Economic Risk Analysis in Wind and Pumped Hydro Energy Storage Integrated Power System Using Meta-Heuristic Algorithm

“…The CVaR model for time-varying economic risk with time-sequential security assessment in a probabilistic model containing uncertainty in EV distribution and renewable energy of distribution system is presented in ref [21]. Risk due to reserve shortage while the optimal allocation of reserve capacity for islanded microgrid operation under intermittency of renewable and fluctuation in load is modeled using CVaR in [22]. Risks due to uncertainty associated with solar energy, price, load, and EV's arriving and departing times in optimal scheduling of heating, power, and hydrogen-based micro grid incorporated with renewable energy sources (RES)-PV and plug-in electric vehicle (PEV) are modeled using CVaR in ref.…”

Decision-making Method of Sharing Mode for Multi-microgrid System Considering Risk and Coordination Cost

“…M ICROGRID (MG) is a small and controllable power grid that integrates distributed generations (e.g., wind and solar generation), loads, and energy storage devices [1]. MG not only provides power for its internal loads, but also acts as an independent stakeholder participating in electricity trading [2].…”