228 research outputs found
Optimal battery charge/discharge strategies for prosumers and suppliers
We discuss the application of classical variational methods to optimal charging/discharging strategies for a prosumer or storage supplier, where the price of electrical power is known in advance. We outline how a classical calculus of variations approach can be applied to two related problems: (i) how can a prosumer minimise the cost of charging/discharging a battery, when the price of electrical power is known throughout the charging/discharging period? and (ii) how can an electricity supplier incentivise desired prosumer/storage supplier behaviour by adjusting the price
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Optimal energy management for a flywheel-assisted battery electric vehicle
Battery electric vehicles are crucial to the reduction in the dependence on fossil fuels and for moving towards a zero-emission transport system. Although battery electric vehicle technology has been rapidly improving, the limited driving range and the high cost are significant impediments to the popularity of electric vehicles. The battery is the main element which affects the range and the cost of the vehicle. The batteries can provide either high power or high energy but not both. Hybridisation of the energy source is one of the methods to improve the energy efficiency of the vehicle, which involves combining a high-energy battery with a high-power source. High-speed flywheels have attractive properties and low-cost potential which makes them excellent secondary energy storage devices to be used in hybrid and electric vehicles. They are utilised to load the battery to a level so as to protect it from peak loads and to enhance its capacity and life. The flywheel is coupled to the drive line with a continuously variable transmission. This paper presents the optimal energy management strategy for a mechanically connected flywheel-assisted battery electric vehicle powertrain. The optimisation problem is complex because of factors such as the small storage capacity of the flywheel, the kinematic constraints and the slipping of clutches. Dynamic programming is used to calculate the optimal control strategy for torque distribution during operation in real-world driving cycles. The results show significant potential for reduction in the energy consumption in extra-urban and highway cycles, while reducing the peak battery loads during all cycles. The results give a benchmark of the energy-saving potential for such a powertrain and insights into how a real suboptimal controller can be designed
Modelling driving behaviour and its impact on the energy management problem in hybrid electric vehicles
Perfect knowledge of future driving conditions can be rarely assumed on real applications when optimally splitting power demands among different energy sources in a hybrid electric vehicle. Since performance of a control strategy in terms of fuel economy and pollutant emissions is strongly affected by vehicle power requirements, accurate predictions of future driving conditions are needed. This paper proposes different methods to model driving patterns with a stochastic approach. All the addressed methods are based on the statistical analysis of previous driving patterns to predict future driving conditions, some of them employing standard vehicle sensors, while others require non-conventional sensors (for instance, global positioning system or inertial reference system). The different modelling techniques to estimate future driving conditions are evaluated with real driving data and optimal control methods, trading off model complexity with performance.Guardiola García, C.; Plá Moreno, B.; Blanco Rodriguez, D.; Reig Bernad, A. (2014). Modelling driving behaviour and its impact on the energy management problem in hybrid electric vehicles. International Journal of Computer Mathematics. 91(1):147-156. doi:10.1080/00207160.2013.829567S147156911Ericsson, E. (2001). Independent driving pattern factors and their influence on fuel-use and exhaust emission factors. Transportation Research Part D: Transport and Environment, 6(5), 325-345. doi:10.1016/s1361-9209(01)00003-7Q. Gong, P. Tulpule, V. Marano, S. Midlam-Mohler, and G. Rizzoni,The role of ITS in PHEV performance improvement, 2011 American Control Conference, June–July, San Francisco, CA, 2011, pp. 2119–2124.C. Guardiola, B. Pla, S. Onori, and G. Rizzoni,A new approach to optimally tune the control strategy for hybrid vehicles applications, IFAC Workshop on Engine and Powertrain Control, Simulation and Modeling E-COSM’12, October, Rueil-Malmaison, France, 2012.Johannesson, L., Asbogard, M., & Egardt, B. (2007). Assessing the Potential of Predictive Control for Hybrid Vehicle Powertrains Using Stochastic Dynamic Programming. IEEE Transactions on Intelligent Transportation Systems, 8(1), 71-83. doi:10.1109/tits.2006.884887Liu, S., & Yao, B. (2008). Coordinate Control of Energy Saving Programmable Valves. IEEE Transactions on Control Systems Technology, 16(1), 34-45. doi:10.1109/tcst.2007.903073Paganelli, G. (2001). General supervisory control policy for the energy optimization of charge-sustaining hybrid electric vehicles. JSAE Review, 22(4), 511-518. doi:10.1016/s0389-4304(01)00138-2Rizzoni, G., Guzzella, L., & Baumann, B. M. (1999). Unified modeling of hybrid electric vehicle drivetrains. IEEE/ASME Transactions on Mechatronics, 4(3), 246-257. doi:10.1109/3516.789683Control of hybrid electric vehicles. (2007). IEEE Control Systems, 27(2), 60-70. doi:10.1109/mcs.2007.338280L. Serrao, S. Onori, and G. Rizzoni,ECMS as realization of Pontryagin's minimum principle for HEV control, 2009 American Control Conference, June, Saint Louis, MO, 2009, pp. 3964–3969.Serrao, L., Onori, S., & Rizzoni, G. (2011). A Comparative Analysis of Energy Management Strategies for Hybrid Electric Vehicles. Journal of Dynamic Systems, Measurement, and Control, 133(3). doi:10.1115/1.4003267Stockar, S., Marano, V., Canova, M., Rizzoni, G., & Guzzella, L. (2011). Energy-Optimal Control of Plug-in Hybrid Electric Vehicles for Real-World Driving Cycles. IEEE Transactions on Vehicular Technology, 60(7), 2949-2962. doi:10.1109/tvt.2011.2158565Sundström, O., Ambühl, D., & Guzzella, L. (2009). On Implementation of Dynamic Programming for Optimal Control Problems with Final State Constraints. Oil & Gas Science and Technology – Revue de l’Institut Français du Pétrole, 65(1), 91-102. doi:10.2516/ogst/2009020O. Sundström and L. Guzzella,A generic dynamic programming Matlab function, 18th IEEE International Conference on Control Applications Part of 2009 IEEE Multi-conference on Systems and Control, July, Saint Petersburg, 2009, pp. 1625–1630.R. Wang and S.M. Lukic,Review of driving conditions prediction and driving style recognition based control algorithms for hybrid electric vehicles, Vehicle Power and Propulsion Conference (VPPC), 2011 IEEE, September 6–9, Raleigh, NC, 2011, pp. 1–7
Ozone tertiary treatment for pharmaceuticals and personal care products removal from municipal wastewater
An ozone pilot plant was installed at a conventional WWTP to evaluate the removal rate of emerging contaminants, drugs, and fragrances, as tertiary treatment. The filtered secondary effluent flow rate ranged between 1.3÷1.9 m3/h with a retention time of 10÷30 minutes and the plant operated with an ozone dose of 2- 4 mgO3/l. The results evidenced a high removal rate of 80-100% for most of the organic targeted compounds: Amisulpride, Azithromycin, Carbamazepine, Diclofenac, Clarithromycin and Ofloxacin. Lower removal rates from 20% to 80%, were observed for some substances e.g. Gabapentin Lactam, Galaxolidone, Irbesartan, Lamotrigine, and Tonalide. Advanced Oxidation Process (AOP) treatment with O3/H2O2, (0.5–1.0–2 molH2O2/molO3) allowed improved results for almost all these latter. In addition, ozone determined up to 42% removal of the absorbance at 254 nm and 20% of COD, wastewater disinfection, a decrease of the GC-MS chromatographic area, and no acute toxicity effect nor estrogenic and mutagen effects have been detected
A7. SITUAZIONE NAZIONALE: CORPI IDRICI INTERESSATI DA CIANOBATTERI TOSSICI
I cianobatteri sono diffusi in moltissimi ambienti acquatici, dove possono produrre cianotossine con diversi
profili tossicologici. Il presente rapporto riporta le linee guida per la gestione delle fioriture di cianobatteri nelle
acque di balneazione, elaborate da un gruppo di esperti. La prima parte sintetizza le attuali conoscenze scientifiche su vari aspetti, fra cui la loro presenza nei laghi italiani, le caratteristiche chimiche e tossicologiche delle varie
cianotossine, gli effetti osservati sulla salute dell\u2019uomo e la valutazione del rischio. La seconda parte definisce le
linee guida per prevenire effetti dannosi per la salute dei bagnanti e gestire il rischio associato alle fioriture. Vengono
fornite indicazioni per pianificare attivit\ue0 di monitoraggio ambientale e sorveglianza sanitaria nelle aree a maggiore
criticit\ue0. Viene inoltre presentato un sistema di reportistica, ambientale e sanitario, anche allo scopo di uniformare le
informazioni a livello nazionale. Il rapporto \ue8 completato dalle indicazioni tecniche rivolte alle strutture territoriali
preposte.Cyanobacteria thrive in many aquatic environments, where they can produce cyanotoxins with different
toxicological profiles. This report provides the guidelines for the management of cyanobacterial blooms in bathing
water, put together by a group of experts. The first part summarizes the current scientific knowledge on various
aspects, including their presence in the Italian lakes, chemical and toxicological characteristics of different
cyanotoxins, the observed effects on human health and the risk assessment. The second part defines the guidelines to prevent harmful effects on the health of bathers and manage the risk associated with blooms. It provides
recommendations for planning environmental monitoring activities and a health surveillance system in most critical
areas. It also introduces an environmental and health reporting system, with the purpose to standardize the
information at national level too. The report is supplemented by technical information aimed at territorial authorities
in charge
Ecotoxicity Thresholds for Ametryn, Diuron, Hexazinone and Simazine in Fresh and Marine Waters
Triazine and urea herbicides are two groups of photosystem II inhibiting herbicides frequently detected in surface, ground and marine waters. Yet, there are few water quality guidelines for herbicides. Ecotoxicity thresholds (ETs) for ametryn, hexazinone and simazine (triazine herbicides) and diuron (a urea herbicide) were calculated using the Australian and New Zealand method for deriving guideline values to protect fresh and marine ecosystems. Four ETs were derived for each chemical and ecosystem that should theoretically protect 99, 95, 90 and 80% of species (i.e. PC99, PC95, PC90 and PC80, respectively). For all four herbicides, the phototrophic species were significantly more sensitive than non-phototrophic species, and therefore, only the former data were used to calculate the ETs. Comparison of the ET values to measured concentrations in 2606 samples from 15 waterways that discharge to the Great Barrier Reef (2011–2015) found three exceedances of the simazine PC99, regular exceedances (up to 30%) of the PC99 in a limited number of rivers for ametryn and hexazinone and frequent (> 40%) exceedances of the PC99 and PC95 ETs in at least four waterways for diuron. There were no exceedances of the marine ETs in inshore reef areas. Further, ecotoxicity data are required for ametryn and hexazinone to fresh and marine phototrophic species, for simazine to marine phototrophic species, for tropical phototrophic species, repeated pulse exposures and long-term (2 to 12 months) exposures to environmentally relevant concentrations.Griffith Sciences, Griffith Institute for Drug DiscoveryNo Full Tex
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