Grid-connected Micro Research Articles

Analytical review study of the Grid connected Micro grid Energy Management System

As an environmentally friendly method of distributing energy production, the integration of photovoltaic systems into micro grids has drawn in significant focus on. Our goal in doing is to examine features regarding micro grid that is linked to the power grid, with a focus on photovoltaic energy management in particular. Finding the optimal micro grid capacity for the solar system seeks to increase energy efficiency, decrease dependence on main grid, and promote an utilization of green power. The outlined optimization approach evaluates the micro grid’s dynamic interactions using state-of-the-art modelling and simulation tools. These components include photovoltaic panels, energy storage systems, alongside the main grid. The refinement method takes into account crucial factors including patterns of load demand, costs of the grid electricity, and variations in solar irradiation. Finding a happy medium between increasing the amount of power generated by renewable sources and decreasing overall energy costs is the objective. That study takes a multi-scenario approach to determining how various micro grid sizes affect overall system efficiency. Using scenario-based simulations and techno-economic criteria, the appropriate size of the photovoltaic system was determined. Factors like payback time, ROI, and system reliability are taken into account here. The study’s findings provide light on grid-connected micro grids, particularly in regards to photovoltaic energy management, which is crucial for their planning and implementation. In order to make educated decisions towards more robust and ecologically friendly power systems, stakeholders, lawmakers, and decision-makers can use the optimal micro grid size as a benchmark for future renewable power projects. This paper reviews the relevant literature and proposes a division and performance strategy based on its findings. By classifying energy management into three groups according to grid connection, configuration, and control method, this article provides a description of the performance, application, advantages, and disadvantages of algorithms that may be used as a reference for selecting an appropriate algorithm. Also included is a comparison table for the control strategies that were used to regulate a micro grid system that is connected to the grid.

WITHDRAWN: Fuzzy Logic-Based energy Management system design for residential Grid-Connected micro grids

This article has been retracted at the request of the Publisher. The authors have plagiarized parts of a paper that had already appeared as D. Arcos-Aviles, J. Pascual, L. Marroyo, P. Sanchis and F. Guinjoan, "Fuzzy Logic-Based Energy Management System Design for Residential Grid-Connected Microgrids," in IEEE Transactions on Smart Grid, vol. 9, no. 2, pp. 530-543, March 2018, doi: 10.1109/TSG.2016.2555245. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal .

Study of Modeling of Hybrid Energy System for Optimum Power Extraction from the System to the Grid

With the growing demand of electricity, deployment of micro grid is becoming an attractive option to meet the energy demands. At present, large-scale wind/solar hybrid system is of great potential for development. The large-scale wind/solar hybrid system is of higher reliability compared with wind power generation alone and solar power generation alone However, a grid-connected micro grid suffers from critical stability problems during a power grid failure. For stable operation of the micro grid during a grid failure. In this paper, the transition stability of the micro grid is examined during a power failure

Maximizing energy efficiency of islanded micro water-energy nexus using co-optimization of water demand and energy consumption

Water and energy systems are interdependent. However, at national and international levels, energy and water systems have been designed individually. To optimize the use of energy resources and have a more sustainable energy processes, a new formulation is proposed in this paper to optimize the energy consumption of water-energy systems at a community scale. More specifically, single-objective, bi-level, and co-optimization models are developed to minimize the energy consumption of a micro water distribution network concerning three scenarios: (1) standalone operation; (2) integrated with a grid-connected micro energy system with no storage unit; and (3) integrated with an off-grid micro energy system with storage units. In all conditions, a mixed integer nonlinear programming formulation is used to solve the optimization problems. Pump operations with varying statuses, flow rates, and speeds are contemplated to formulate the energy consumption of the micro water, considering a quadratic function for the pump’s energy head changing with flow rate. The micro water network is designed based on a diurnal pattern of water demand for a network including 1 reservoir, 1 water tank, 6 nodes, and 2 pumps. The micro energy system includes a microgrid with a combined heat and power plant (CHP), diesel (DS) generator, natural gas (NG) generator, renewable sources (solar and wind), and energy storage units. Several case studies are carried out to compare the performance of developed optimization models.

A hybrid heuristic algorithm for optimal energy scheduling of grid-connected micro grids

The micro grids (MG) are small-scaled and restricted energy systems using distributed energy sources and storages. They can be operated in two different ways; grid-connected or islanded modes. The shifting between the modes depends on the volatility of demand. The use islanded mode is beneficiary as it helps minimizing the amount of power bought from main grid. It is not always possible unless a fertile field is found. This study proposes a hybrid heuristic approach for optimal management of MG considering regional conditions and constraints. For a power generating MG, the use of renewable resources in that region is as important as exchanging power with the main grid. MG is constructed in an industrial zone where the hourly power demand has to be matched. The aim is to schedule the power loads to minimize the amount of power taken from the main grid. To deal with this complex problem which contains power generation and consumption constraints, a versatile mathematical model must be established. The mathematical model needs to be integrated with a hybrid heuristic algorithm. Thus, a hybrid Genetic Algorithm (GA)–Simulated Annealing (SA) method is proposed for solution. The schedule is programmed using GA, while, parameters are optimized by using SA. In the application stage, a MG in Gebze is simulated with three factories as consumers, where, grid connection and a wind turbine together with photovoltaic panels are assumed to be in use.

Control Strategy for MGT Generation System Optimized by Improved WOA to Enhance Demand Response Capability

The grid-connected micro gas turbine (MGT) generation system is playing an important role in power systems because of its demand response capability and application in combined heat and power (CHP) systems. When applied to promote demand response, the generation system is expected to respond to follow instructions quickly, but a rapid response harms the safety and is not conducive to the benefits of customers, which leads to a contradiction. In this paper, a closed-loop power control is introduced for the MGT to improve demand response capability. The rate of fuel valve opening is limited so as to protect the equipment from thermal fatigue threats. An optimization method is developed for identifying the control parameters, balancing the response time and unrealized energy in the regulation process. An improved whale optimization algorithm (IWOA) is proposed to implement the optimization. Results of the algorithm performance verify that WOA is competitive with other heuristic algorithms, and IWOA is more suitable for parameter optimization problems than WOA because of better efficiency and exploitation capability. Results of power response further indicate that the proposed control strategy can achieve expected aims and is suitable for the MGT generation system.

IMPROVING POWER QUALITY IN MICROGRID BY MEANS OF USING POWER QUALITY CONDITIONER DEVICES

The micro grids and the utility grid expose to their inner disturbance such as harmonics, unbalances and other power quality noises. To better isolate the device from their respective noises power quality conditioner is recommended between each micro grid and the utility grid. The cooperative control for enhance voltage harmonics and unbalances in micro grids is mentioned. The power quality enhancement of grid-interactive micro grids is discussed and explained. Power quality problem is reduced by means of using Unified Power Quality Conditioner (UPQC) in grid-connected micro grids is introduced in order to reduce harmonics in transmission and improve the power quality in distribution. Power quality problem includes voltage unbalances and harmonics. Interline Power Quality Conditioner (IPQC) is proposed to improve the power quality in multiline by reducing the harmonics and also unbalances of power in feeders by the process of synchronization. Finally, the coordinated control of harmonics and unbalances in micro grids is simulated by using MATLAB and the satisfactory results are obtained.

Grid-Connected Solar Microinverter Study and Design Using a dsPIC Digital Signal Controller

An interleaved flyback converter using a dsPIC digital signal controller is researched and designed, regarding to photovoltaic (PV) grid-connected micro inverter’s characteristics, the system structure and control principles is studied, and a new method combining Constant Voltage (CV) and Perturb and Observe(P&O) to track the Maximum Power Point (MPP) is applied. The prototype experiments verify that the inverter can better realize the most power tracing and island detection function, at the same time reduce the current output ripple, lower its THD.

An efficient scenario-based stochastic programming framework for multi-objective optimal micro-grid operation

This paper proposes a stochastic model for optimal energy management with the goal of cost and emission minimization. In this model, the uncertainties related to the forecasted values for load demand, available output power of wind and photovoltaic units and market price are modeled by a scenario-based stochastic programming. In the presented method, scenarios are generated by a roulette wheel mechanism based on probability distribution functions of the input random variables. Through this method, the inherent stochastic nature of the proposed problem is released and the problem is decomposed into a deterministic problem. An improved multi-objective teaching–learning-based optimization is implemented to yield the best expected Pareto optimal front. In the proposed stochastic optimization method, a novel self adaptive probabilistic modification strategy is offered to improve the performance of the presented algorithm. Also, a set of non-dominated solutions are stored in a repository during the simulation process. Meanwhile, the size of the repository is controlled by usage of a fuzzy-based clustering technique. The best expected compromise solution stored in the repository is selected via the niching mechanism in a way that solutions are encouraged to seek the lesser explored regions. The proposed framework is applied in a typical grid-connected micro grid in order to verify its efficiency and feasibility.