Search results for "MICROGRID"
showing 10 items of 83 documents
REGULATION DROOP COEFFICIENTS IN ISLANDED MICROGRIDS
In this thesis, a novel non-linear droop control is proposed. The droop curve is generated as a piecewise linear curve from the optimized operating points of the system under consideration for different values of the supplied load. For each Optimal Power Flow (OPF), the droop coefficients are generated and these create small piecewise linear parts of the final droop curve. The operation is constrained by frequency and voltage limits. It is well known that the load flow problem solution can provide infinite operating points if the generators set point is not fixed. For each loading condition, the solution to the OPF problem outputs a single solution. Such solution, in case of microgrids with…
Demand Response Pricing Strategies for Islanded Microgrids
2013
In this paper, Time of Use and Critical Peak Pricing policies are designed and their effects on optimized operation is evaluated. For this purpose, an optimal operation algorithm is employed and the relevant production costs are derived. As far as the Time of Use policy is concerned, such costs are observed to be different in two time intervals of the day, due to the loads changing effect and the production of renewable energy. Whereas in the Critical Peak Pricing Policy, a peak time interval is identified to set up different pricing rates. The optimization algorithm used to carry out the work described above minimizes the microgrid's energy losses, the production costs and the Green House …
A Technical Approach to the Energy Blockchain in Microgrids
2018
The present paper considers some technical issues related to the “energy blockchain” paradigm applied to microgrids. In particular, what appears from the study is that the superposition of energy transactions in a microgrid creates a variation of the power losses in all the branches of the microgrid. Traditional power losses allocation in distribution systems takes into account only generators while, in this paper, a real-time attribution of power losses to each transaction involving one generator and one load node is done by defining some suitable indices. Besides, the presence of P–V nodes increases the level of reactive flows and provides a more complex technical perspective. For this re…
CONTROLLO DELLA CONVERSIONE DELL'ENERGIA ELETTRICA IN MICRORETI INTELLIGENTI
La limitatezza delle fonti fossili, insieme agli effetti ambientali del loro sfruttamento, hanno portato la ricerca a trovare fonti energetiche alternative poco inquinanti e facilmente reperibili. Lo sviluppo delle fonti rinnovabili e la crescente attenzione verso l’efficienza hanno permesso l'integrazione di un nuovo sistema di distribuzione dell’energia non più centralizzato, ma basato sulla generazione distribuita, permettendo all'occorrenza anche il funzionamento in autonomia di sottosistemi della rete comprendenti generazione locale e carichi, detti microgrid (µG). Una µG (fig.1) è quindi un insieme di carichi e sorgenti di energia operanti come un unico sistema [1] e che presenta innu…
Challenges and Opportunities for Renewable-Based Microgrids Integration in Vietnam
2020
Vietnam is among the South-Asian regions the one that better supplies remote areas. However, many islands and remote areas are still not connected to the main grid and this fact jeopardizes their development, while forcing people to move to urban areas. With a high potential from renewable energy sources and a lot of islands, Vietnam has thus many favorable environmental features for developing the microgrids technology. In this chapter, a detailed analysis about opportunities and challenges for widespread deployment of microgrids technology in Vietnam is considered. Such analysis is based on the assessments of the potential from renewable energy sources in the country and of the national p…
Modeling and Experimental Validation of a Voltage-Controlled Split-Pi Converter Interfacing a High-Voltage ESS with a DC Microgrid
2023
The Split-pi converter can suitably interface an energy storage system (ESS) with a DC microgrid when galvanic isolation is not needed. Usually, the ESS voltage is lower than the grid-side voltage. However, limitations in terms of the ESS current make the use of a high-voltage ESS unavoidable when high power levels are required. In such cases, the ESS voltage can be higher than the microgrid voltage, especially with low microgrid voltages such as 48 V. Despite its bidirectionality and symmetry, the Split-pi exhibits a completely different dynamic behavior if its input and output ports are exchanged. Thus, the present work aims to model the Split-pi converter operating with an ESS voltage hi…
Adaptive Energy Management Strategy for Optimal Power Flow Control of Hybrid DC Microgrid
2020
In this work, an adaptive energy management strategy (AEMS) is proposed to achieve the optimal power flow control of off grid connected hybrid DC Microgrid (MG) against time varying source and load dynamics. The hybrid DC MG considered in this paper is operating with a solar PV array and mini hydro power plant (MHPP) as power dispatching sources. The intermittent input dynamics of solar PV system and time varying load power dynamics results in power fluctuations of hybrid DC MG. The MHPP cannot regulate these power fluctuations instantly due its operating dynamics. Therefore, AEMS has deployed a hybrid energy storage system (HESS) comprising battery and supercapacitor storage devices for co…
Demand Response Service Certification and Customer Baseline Evaluation Using Blockchain Technology
2020
The use of Distributed Ledger Technologies such as Blockchain for certifying Demand Response services allows for the creation of a distributed system in which customers can communicate with the system operator to provide their flexibility, in a secure, transparent and traceable way. Blockchain technology also supports incentive mechanisms for users taking part in the service through the generation of utility tokens to recognize the user's contribution. This paper presents the experimental test of a novel methodology for Demand Response programs implementation by using the Blockchain technology. The latter is employed for defining a distributed Demand Response service and a new system for it…
Solar photovoltaic‑based microgrid hosting capacity evaluation in electrical energy distribution network with voltage quality analysis
2021
Abstract In this paper, solar photovoltaic hosting capacity within the electrical distribution network is estimated for different buses, and the impacts of high PV penetration are evaluated using power hardware-in-loop testing methods. It is observed that the considered operational constraints (i.e. voltage and loadings) and their operational limits have a significant impact on the hosting capacity results. However, with increasing photovoltaic penetration, some of the network buses reach maximum hosting capacity, which affects the network operation (e.g. bus voltages, line loading). The results show that even distributing the maximum hosting capacity among different buses can increase the…
Optimizing the generation system in a microgrid with power, thermal energy and mobility demands
2021
Microgrids are widely known to be the future of generation and distribution systems. This paper presents a method to optimize the size of the main components in a microgrid to supply the demands for electricity, heating and hydrogen for mobility through an Energy Hub model. The electricity production from a wind turbine, a CHP and a fuel cell satisfies the local electricity demand. The green hydrogen produced in the hub from renewable power in off-peak hours is used to feed the fuel cell or to meet the mobility demand. The heating power from CHP and fuel cell is used to feed the local district heating network.