renewable sources integration through the optimization of the load for residential applications

Abstract This work presents the implementation of two different control strategies for the control of Microgrids a Model Predictive Control (MPC) technique coupled with a Mixed-Integer Linear Program (MILP) structure and a Rule Based Control (RBC) strategy both applied to a residential MicroGrid. The validation of the models has been performed with an experimental setup laid out in the laboratory of University of Rome - Tor Vergata. Results obtained show that MicroGrids connected to the main network have enough potential to support grid balancing actions, thus allowing for a greater penetration of renewable sources into the mix, and giving economic benefits for both end users and providers. In particular, using a MPC strategy major benefits can be obtained in terms of reduction of the unbalanced energy exchange with the main grid and a more efficient use of the micro-grid components

Optimal Scheduling of Energy Storage Using A New Priority-Based Smart Grid Control Method

This paper presents a method to optimally use an energy storage system (such as a battery) on a microgrid with load and photovoltaic generation. The purpose of the method is to employ the photovoltaic generation and energy storage systems to reduce the main grid bill, which includes an energy cost and a power peak cost. The method predicts the loads and generation power of each day, and then searches for an optimal storage behavior plan for the energy storage system according to these predictions. However, this plan is not followed in an open-loop control structure as in previous publications, but provided to a real-time decision algorithm, which also considers real power measures. This algorithm considers a series of device priorities in addition to the storage plan, which makes it robust enough to comply with unpredicted situations. The whole proposed method is implemented on a real-hardware test bench, with its different steps being distributed between a personal computer and a programmable logic controller according to their time scale. When compared to a different state-of-the-art method, the proposed method is concluded to better adjust the energy storage system usage to the photovoltaic generation and general consumption.Unión Europea ID 100205Unión Europea ID 26937

Time programmable smart devices for peak demand reduction of smart homes in a microgrid

Abstract: Increasing electricity access through Microgrids for rural areas is often faced with the challenge of increased peak demand through increased electricity demand as more electronic devices will be acquired by the consumers and more small businesses will spring up in the community. If not taken care of, this leads to additional cost of incurring higher peaker plants to meet the peak demand, and the burden of the cost of peaker plants are consequentially transferred to the consumers. Since this load is generated by the consumers, it is most desirable to control the peak demand from the consumers’ side. Therefore, a method of Time Programmable Smart Devices (TPSD) with an efficient Electricity Use Plan (EUP) is proposed in this paper by introducing appliance working knowledge and improving load shifting technique of Demand Side Management for peak demand reduction in a rural Microgrid. This method yielded lower morning and evening peaks, a lower peak-to-peak difference than those available in literature, and a peak period shift from the traditional peak period to traditional off-peak period. These lead to financial savings, reduced cost of peaker plants and a safer environment from less greenhouse gases emissions

Grid-connected Microgrids to Support Renewable Energy Sources Penetration

Abstract Distributed generation systems and microgrids are instrumental for a greater penetration of renewables to achieve a substantial reduction on carbon emissions. However, microgrids performances and reliability strongly depend on the continuous interaction between power generation, storage and load requirements, highlighting the importance in developing a proper energy management strategy and the relative control system. In this work a Model predictive Control (MPC) strategy, based on a Mixed Linear Integer Programming framework, has been applied to a residential microgrid case. Theoretical results obtained confirm that grid connected microgrids have potential capabilities in grid balancing allowing for a larger penetration of fluctuating renewable energy sources and thus producing economic benefits for both end-user and grid operators. A microgrid test bench to reproduce previous microgrid model is also presented in the paper. The experimental setup has been used to validate results obtained from simulation. Results obtained confirm the potential of this solution and its real applicability

Review of trends and targets of complex systems for power system optimization

Optimization systems (OSs) allow operators of electrical power systems (PS) to optimally operate PSs and to also create optimal PS development plans. The inclusion of OSs in the PS is a big trend nowadays, and the demand for PS optimization tools and PS-OSs experts is growing. The aim of this review is to define the current dynamics and trends in PS optimization research and to present several papers that clearly and comprehensively describe PS OSs with characteristics corresponding to the identified current main trends in this research area. The current dynamics and trends of the research area were defined on the basis of the results of an analysis of the database of 255 PS-OS-presenting papers published from December 2015 to July 2019. Eleven main characteristics of the current PS OSs were identified. The results of the statistical analyses give four characteristics of PS OSs which are currently the most frequently presented in research papers: OSs for minimizing the price of electricity/OSs reducing PS operation costs, OSs for optimizing the operation of renewable energy sources, OSs for regulating the power consumption during the optimization process, and OSs for regulating the energy storage systems operation during the optimization process. Finally, individual identified characteristics of the current PS OSs are briefly described. In the analysis, all PS OSs presented in the observed time period were analyzed regardless of the part of the PS for which the operation was optimized by the PS OS, the voltage level of the optimized PS part, or the optimization goal of the PS OS.Web of Science135art. no. 107

House Management System with Real and Virtual Resources: Energy Efficiency in Residential Microgrid

The reduction of the greenhouse gas emissions is a priority all around the globe. The investment on renewable energy sources is contributing for new opportunities in the context of the smart grids and microgrids. Recent advances are transforming the consumer into a prosumer, being able to adapt the consumption depending on its own generated power, and selling the surplus or buying the missing power. In this context, home management systems are emerging as an effective means to support the management of energy resources in the context of communication between functions/devices of a smart home. This paper presents a new agent-based home energy management approach, using ontologies to enable semantic communications between heterogeneous multi-agent entities. The main goal is to support an efficient energy management of end consumers in the context of microgrids, obtaining a scheduling for both real and virtual resources. A case study is presented, which simulates a 25-bus microgrid that includes a laboratorial controlled house (with real and simulated resources), which is managed by the proposed energy management system.info:eu-repo/semantics/publishedVersio

Software Defined Networks based Smart Grid Communication: A Comprehensive Survey

The current power grid is no longer a feasible solution due to ever-increasing user demand of electricity, old infrastructure, and reliability issues and thus require transformation to a better grid a.k.a., smart grid (SG). The key features that distinguish SG from the conventional electrical power grid are its capability to perform two-way communication, demand side management, and real time pricing. Despite all these advantages that SG will bring, there are certain issues which are specific to SG communication system. For instance, network management of current SG systems is complex, time consuming, and done manually. Moreover, SG communication (SGC) system is built on different vendor specific devices and protocols. Therefore, the current SG systems are not protocol independent, thus leading to interoperability issue. Software defined network (SDN) has been proposed to monitor and manage the communication networks globally. This article serves as a comprehensive survey on SDN-based SGC. In this article, we first discuss taxonomy of advantages of SDNbased SGC.We then discuss SDN-based SGC architectures, along with case studies. Our article provides an in-depth discussion on routing schemes for SDN-based SGC. We also provide detailed survey of security and privacy schemes applied to SDN-based SGC. We furthermore present challenges, open issues, and future research directions related to SDN-based SGC.Comment: Accepte

Manual for Automation of Dc-microgrid Component Using Matlab/Simulink and FPGA\u27s

Solar Energy is one of the abundantly available renewable energy source. Solar panels are semiconductor materials which capture the solar energy from every band in the visible light spectrum, infrared spectrum and ultra violet spectrum and converts it into electrical energy. The DC community microgrid is used to supplement utility electrical power supplied to the neighbored with renewable sources such as solar panels, emergency back-up power through batteries or generators. Smart Cloud Interconnected environment increases the standard of living and facilitates ease to rectify faults, debug components and reinstate or replace obsolete components with newer ones. Automation of the DC microgrid components provides a simple yet efficient way to connect to the grid and to every component in the grid remotely. It is essential to find the node of failure in the grid for technicians and engineers to work on and to debug the issue to facilitate smooth running of the grid without shutdown. FPGAs are used as target devices for end synthesis of the model that is created on Simulink. These FPGAs are links between cloud and power electronics components. To utilize the energy resource efficiently we need to monitor the input and output of every component at every node in the grid. Simulating models on Simulink will let us connect the component and test engineer to the grid to detect any flaws or failures on time. FPGAs are easily reprogrammable and have long life with excellent capability to withstand stress. This thesis report provides a set of procedures to create and simulate a real time component model and to generate HDL files to build a clean code which can be redeployed on target FPGAs

Optimization Models for islanded micro-grids: A comparative analysis between linear programming and mixed integer programming

This paper presents a comparison of optimization methods applied to islanded micro-grids including renewable energy sources, diesel generators and battery energy storage systems. In particular, a comparative analysis between an optimization model based on linear programming and a model based on mixed integer programming has been carried out. The general formulation of these models has been presented and applied to a real case study micro-grid installed in Somalia. The case study is an islanded micro-grid supplying the city of Garowe by means of a hybrid power plant, consisting of diesel generators, photovoltaic systems and batteries. In both models the optimization is based on load demand and renewable energy production forecast. The optimized control of the battery state of charge, of the spinning reserve and diesel generators allows harvesting as much renewable power as possible or to minimize the use of fossil fuels in energy production

Various approaches for power balancing in grid-connected and islanded microgrids

One of the promising solutions to reduce power imbalance, an undesired impact of intermittent renewable energy sources, is to supply the loads by means of local distributed energy resources in the form of a microgrid. Microgrids offer several benefits such as reduction of line losses, increased system reliability, and maximum utilisation of local energy resources. A microgrid, during its islanded operation, is more susceptible to the frequency and voltage fluctuation caused by a sudden dispatch either from the generation or load. Therefore, additional control is required to manage either the output power from the generation side or the demand from the end-user side. Thus, appropriate and efficient control and monitoring systems need to be installed. However, the cost of such a system will reduce the rate of investment return on microgrid projects. This research has focused on developing various techniques to maintain the voltage and frequency within acceptable limits in microgrids, taking into account various influencing factors. This study proposes an additional active power management technique through the use of inverters, that can maintain the microgrid’s frequency when the generated power in the microgrid is much higher than its demand. Also, to facilitate the microgrid’s transition from grid-connected to islanded mode, the inverters can be controlled with a soft starting ramp. Moreover, a control function employing a droop control method is proposed in order to reduce the output power of the renewable sources when the microgrid frequency is much higher than the nominal frequency. On the other hand, when the demand is higher than the generated power, managing the demand under a demand response program is proposed as a means of maintaining the microgrid stability. This is an inexpensive solution which will not reduce the rate of investment return on the microgrid project. However, this requires the installation of appropriate enabling technologies at the utility and end-user sides. Moreover, the participation from demand response participants is influenced by the profit earned from engaging in the program. Therefore, in this research, the technical and economic benefits of demand response deployment are analysed in detail. The execution of the demand response program through load-shifting, reducing the appliances’ consumed power, and load-shedding causes customer discomfort. To minimise this discomfort, in this thesis, suitable strategies are suggested for various groups of loads. Furthermore, each load profile contains information on its capacity, flexibility, and operating time. The proposed approach ensures that the loads with a larger capacity and flexibility are the most preferred ones to be controlled during demand response events so that customer discomfort and the number of affected loads can be minimised. Also, this study examines the load’s economic value, power losses, emission factor, and cost of energy production to maximise the microgrid operator’s profit as a result of deploying the demand response program. Meanwhile, to encourage end-users’ engagement in demand response programs, the microgrid operator should offer incentives to the customer as compensation for any incurred costs and discomfort felt. The given incentives should be such that both the microgrid operator and the end-user gain the maximum profit. Therefore, this study proposes an approach for calculating the level of incentives that should be given to the participants by comparing the differences between ongoing revenue and the cost of energy with and without demand response