Abstract-The uptake of variable Mega Watts(MW) from

Abstract-The uptake of variable Mega Watts(MW) from

-This work presents a probabilistic economic dispatch tool for energy management (EM) studies in the context of remote hybrid AC/DC microgrids (MGs). An EM approach is proposed to ensure a reliable power supply at the minimum cost of the hybrid MG operation. A comprehensive operational framework is presented, which considers topological features of the hybrid MG and the interlinking converter between AC and DC subsections. Approach and models are tested using several operating scenarios referred to a test hybrid MG system. In the analyses, the opportunity of integrating battery energy storage and energy demand management in the EM scheme is investigated. The results of the analyses demonstrate the effectiveness and practicality of the optimization tool in different operation contexts. -represent a more likely architecture. Hybrid MGs can be a cost-effective solution to supply affordable and reliable electricity to rural and remote communities, given their unique feature of using locally available generation resources (such as solar, wind, water stream and biomass) to supply the specific demand needs. IndexDespite combining the advantages of AC and DC, operating a hybrid MG brings challenges in power quality, reliability, efficiency and control. There have been several publications addressing dynamics and control of hybrid . Schemes and techniques for the control of AC and DC subsections of a hybrid MG, as well as of their power electronics interface, are examined in [6]-[9], for both grid-connected and islanded modes of operation. Focusing on the interlinking converter between AC bus and DC bus, authors in [9] propose a DC-side hierarchical control scheme to analyze both standalone and grid-connected DC operation. Interaction dynamics in hybrid AC/DC distribution systems are investigated in [10], alongside strategies for their mitigation; in this case, small-signal analysis is used to model the input/output DC-side admittance of the system components. Harmonics analysis and harmonics mitigation methods are studied in [12]-[14] for standalone and grid-connected hybrid systems. Authors in [13] propose, in particular, a reduction method for the zero-sequence circulating currents between parallel AC/DC interlinking inverters, whereas [14] presents a DC bus voltage control scheme to suppress the transient fluctuations of DC-bus voltage and improve power. Finally, [15] presents a back-to-back converter structure for grid-connected hybrid MGs, which can provide isolated and reliable system connection with improved power flow management. Outside this research, what is still missing in the literature is a comprehensive energy management (EM) framework that can incorporate and address the aforementioned issues in a robust manner [5].Optimization-based EM has been well explored in AC MGs or DC . In hybrid MGs, the EM becomes more challenging because of the interconnection between DC side

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Variable over voltage, excessive tap counts, and voltage regulator (VR) runaway condition are major operational challenges in distribution network while accommodating generation from photovoltaics (PVs). The conventional approach to achieve voltage control based on offline simulation for voltage set point calculation does not consider forecast errors. In this work, a stochastic optimal voltage control strategy is proposed while considering load and irradiance forecast errors. Stochastic operational risks such as overvoltage and VR runaway are defined through a chance constrained optimization (CCO) problem. This classical formulation to mitigate runaway is further improved by introducing a stochastic index called the Tap Tail Expectation. Operational objectives such as power losses and excessive tap count minimization are considered in the formulation. A sampling approach is proposed to solve the CCO. Along with other voltage control devices, the PV inverter voltage support features are coordinated. The simulation study is performed using a realistic distribution system model and practically measured irradiance to demonstrate the effectiveness of the proposed technique. The proposed approach is a useful operational procedure for distribution system operators. The approach can minimize feeder power losses, avoid voltage violations, and alleviate VR runaway.Index Terms-Distribution voltage control, photovoltaic (PV) forecast errors, voltage regulator (VR) runaway.