Search

This brief aims at providing a proof of concept of a systematically designed linear parameter varying (LPV)/H∞-based energy management system (EMS) for coordinated multi-variable control of multi-source electrical systems. A three-source electrical system representing the power supply system on board of an electric vehicle has been chosen as a representative example of irregular and generally not a priori known load variation. The power supply system is composed of the fuel cell, battery, and supercapacitor. Each power source is coupled to a dc–dc converter, all converters being connected in parallel to a common dc-bus in order to feed the load represented by the vehicle’s electrical motor. The system is modeled as an LPV system—as its operating point depends on the load—and the control objectives are cast into the H∞ formalism as a disturbance-rejection problem. A dedicated hardware-in-the-loop system was built for the proof-of-concept purpose, with real-world battery and supercapacitor being used, while the fuel cell system is entirely emulated. A dSPACE MicroAutoBox II device embeds the designed EMS, due to its flexibility and ease of programming with MATLAB. A driving cycle from [Institut Français des Sciences et Technologies des Transports, de l’Aménagement et des Réseaux (IFSTTAR)] is chosen as a pertinent scenario of load variation due to its rich frequency content able to challenge all the three sources. Effectiveness of the EMS is assessed in relation to the imposed control objectives—dc-bus voltage regulation, dynamical separation of power sources’ current variations depending on the specialization range of each source, and imposing desired steady-state behavior for each of the three power sources—with very promising results. [ABSTRACT FROM AUTHOR]

This paper describes a new methodology based on the statistical description of driving cycles to size the energy source of a hybrid vehicle. This methodology is applied to a fuel-cell-based collection truck for very specific driving patterns. Based on experimental data, random driving cycles are then generated, allowing the distribution of the average powers and energies to be computed. The analysis proves that a 20-kW fuel cell stack is sufficient for a 13 000-kg truck. The results show that the fuel cell system could be downsized, compared with classical solutions, where much larger fuel cells are required. [ABSTRACT FROM PUBLISHER]

Electrification of the transport sector is one of the 21st century priorities to meet the targets of energy transition. Proton-exchange membrane fuel cells (PEMFC) have been attracting significant attention thanks to their high specific energy and short refuelling time. Despite significant progress, their lifespan is still limited in transport applications. A supporting energy storage system (ESS) is needed to reduce PEMFC sizing, hydrogen consumption and improve its durability. In this paper, nickel–manganese–cobalt (NMC) lithium-ion batteries are considered as supporting ESS. This paper emphasizes electrochemical degradations generated during hybrid operating conditions on PEMFC and NMC batteries. After analysing the operating modes affecting sources durability, their degradation rates are reviewed from the literature in terms of voltage drop for PEMFC and in terms of capacity and power fade for NMC battery. This investigation aims at understanding degradation mechanisms and providing estimations of PEMFC degradation rates to be considered in energy management for hybrid applications. • Proton-exchange membrane fuel cell and battery degradation processes are investigated. • Power sources operating conditions are correlated with chemical consequences. • Power sources degradation rates are classified regarding operating modes. • Degradation rates are estimated to be considered in energy management strategies. [ABSTRACT FROM AUTHOR]

Grid modernization through philosophies such as the Smart Grid has the potential to meet increasing demand and integrate new distributed generation resources at the same time. Using advanced communication and computing capabilities, the Smart Grid offers a new avenue of controlling end-user assets, including small units such as home appliances. To enable such evolution, shifting from centralized to decentralized control strategies is required. Effective demand-side management (DSM) and demand response (DR) approaches hold the promise for efficient energy management in homes and neighborhood areas, by enabling the precise control of resources to reduce net demand. However, with such strategies, independently taken decisions can cause undesired effects such as rebound peaks, contingencies, and instabilities in the network. Therefore, the interactions between the energy management actions of multiple households is a challenging issue in the Smart Grid. This paper provides a review of the background of residential load modeling with DR and DSM approaches in a single household and concepts of coordinating mechanisms in a neighborhood area. The objective of this paper is to classify, via comparison, the various coordination structures and techniques from recent research. The results of recent research in the field reveal that the coordination of energy management in multiple households can benefit both the utility (i.e., the service provider) and the customer. The paper concludes with a discussion on the prevalent critical issues in this area. [ABSTRACT FROM AUTHOR]

Highlights: [•] A multiphysics, 1D, dynamic SOFC model is developed. [•] The presented model is validated experimentally in eight different operating conditions. [•] Electrochemical and thermal dynamic transient time expressions are given in explicit forms. [•] Parameter sensitivity is discussed for different semi-empirical parameters in the model. [Copyright &y& Elsevier]