Train Bi-Control Problem on Riemannian Setting

This article refers to the optimization of the energy consumption of guided traction rails, such as those used for electric trains (including subway electric units), railcars, locomotives, and trams, in a Riemannian framework. The proposed optimization strategy takes into account the compliance time drive and aims at improving the transport system for given operation conditions. Our study has five targets: (1) improving the optimal control techniques; (2) establishing a strategy for the operating conditions of the vehicle; (3) formulating and solving additional problems of optimal movement; (4) improving automatic systems for vehicle traction to optimize energy consumption in a Riemannian context; (5) formulating and solving a problem of maximizing the profit of the train. Some significant figures and formulas obtained by Maple procedures clarify the problems.

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Optimal control of electrical machines using Pontryagin’s maximum principle

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209522 ◽

2020 ◽

pp. 1-15

Author(s):

Wissem Bekir ◽

Lilia EL Amraoui ◽

Frédéric Gillon

Keyword(s):

Optimal Control ◽

Energy Consumption ◽

Maximum Principle ◽

Optimal Solution ◽

Optimization Method ◽

Pontryagin’S Maximum Principle ◽

Electrical Machines ◽

Stepper Motor ◽

Control Techniques ◽

Numerical Resolution

This paper presents an optimization method that deal with control techniques for electrical machines, in order to impose a displacement with a minimum of energy consumption. It’s a generic method; However, its application to electrical machines is complex for implementation. The present work provides the shape of the optimal solution. Moreover, a resolution technique related to the nature of the model is proposed, which facilitate the numerical resolution of costate problem. The method is applied to hybrid stepper motor and the obtained results are then analyzed.

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Thermal Management of Single- and Dual-Tank Fuel-Flow Topologies Using an Optimal Control Strategy

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4040036 ◽

2018 ◽

Vol 10 (4) ◽

Cited By ~ 2

Author(s):

P. G. Huang ◽

D. B. Doman

Keyword(s):

Heat Transfer ◽

Optimal Control ◽

Control Strategy ◽

Linear Quadratic Regulator ◽

Operating Conditions ◽

Adjoint Equations ◽

Linear Quadratic ◽

Optimal Control Strategy ◽

Flow Topology ◽

Operation Conditions

The effect of fuel topology and control on thermal endurance of aircraft using fuel as a heat transfer agent was studied using an optimal dynamic solver (OPT). The dynamic optimal solutions of the differential equations governing the heat transfer of recirculated fuel flows for single- and dual-tank arrangements were obtained. The method can handle sudden jumps of operating conditions across different operating zones during mission and/or situations when control parameters have reached their physical limits. Although this method is robust in providing an optimal control strategy to prolong thermal endurance of aircrafts, it is not ideal for practical application because the method required iterative procedures to solve expensive nonlinear equations. The linear quadratic regulator (LQR), the feedback controller, can be derived by linearizing the adjoint equations at trim points to offer a simple control strategy, which can then be implemented directly in the feedback control hardware. The solutions obtained from both OPT and LQR were compared, and it was found two solutions were almost identical except in regions having sudden jump of operation conditions. Finally, a comparison between single- and dual-tank arrangements was made to demonstrate the importance of the flow topology. The study shows the dual-tank arrangement allows flexibility in how energy is managed and can release energy faster than a single-tank topology and hence provides improved aircraft thermal endurance.

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Cost minimization in a full-scale conventional wastewater treatment plant: associated costs of biological energy consumption versus sludge production

Water Science & Technology ◽

10.2166/wst.2017.423 ◽

2017 ◽

Vol 76 (9) ◽

pp. 2473-2481 ◽

Cited By ~ 10

Author(s):

S. Sid ◽

A. Volant ◽

G. Lesage ◽

M. Heran

Keyword(s):

Wastewater Treatment ◽

Energy Consumption ◽

Energy Demand ◽

Cost Minimization ◽

Cost Optimization ◽

Treatment Plant ◽

Simulation Software ◽

Operating Conditions ◽

Optimization Strategy ◽

Sludge Production

Abstract Energy consumption and sludge production minimization represent rising challenges for wastewater treatment plants (WWTPs). The goal of this study is to investigate how energy is consumed throughout the whole plant and how operating conditions affect this energy demand. A WWTP based on the activated sludge process was selected as a case study. Simulations were performed using a pre-compiled model implemented in GPS-X simulation software. Model validation was carried out by comparing experimental and modeling data of the dynamic behavior of the mixed liquor suspended solids (MLSS) concentration and nitrogen compounds concentration, energy consumption for aeration, mixing and sludge treatment and annual sludge production over a three year exercise. In this plant, the energy required for bioreactor aeration was calculated at approximately 44% of the total energy demand. A cost optimization strategy was applied by varying the MLSS concentrations (from 1 to 8 gTSS/L) while recording energy consumption, sludge production and effluent quality. An increase of MLSS led to an increase of the oxygen requirement for biomass aeration, but it also reduced total sludge production. Results permit identification of a key MLSS concentration allowing identification of the best compromise between levels of treatment required, biological energy demand and sludge production while minimizing the overall costs.

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Electrochemical oxidation of landfill leachates at pilot scale: evaluation of energy needs

Water Science & Technology ◽

10.2166/wst.2010.130 ◽

2010 ◽

Vol 61 (9) ◽

pp. 2211-2217 ◽

Cited By ~ 32

Author(s):

A. Anglada ◽

D. Ortiz ◽

A. M. Urtiaga ◽

I. Ortiz

Keyword(s):

Energy Consumption ◽

Ammonia Concentration ◽

Pilot Scale ◽

Economic Feasibility ◽

Operating Conditions ◽

Boron Doped Diamond ◽

Operation Conditions ◽

Electro Oxidation ◽

Nitrite Nitrate ◽

By Products

Two of the main drawbacks to be overcome before full scale implementation of boron-doped diamond electro-oxidation were addressed in this work; its energy consumption and hazard of formation of chlorinated organics. This was framed within a study in which the technical and economic feasibility of BDD electro-oxidation of landfill leachate was evaluated at pilot scale. On one hand, its technical feasibility was assessed based on COD and NH4+ removal, allowing the selection of the operation conditions that provide optimal energy efficiency, and special attention was paid to the risk of formation of undesired by-products such as nitrite, nitrate ions and trihalomethanes. On the other hand, treatment costs were estimated based on energy consumption required to reach the disposal limits to natural watercourses established by legislation. The results were compared with those of other commonly used AOPs. Under the operating conditions studied, the concentration of COD decreased below the disposal limit (160 mg L−1) and ammonia concentration reached values as low as 30 mg L−1. The energy consumption needed was estimated at 54 kWh/m3 and the formation of chlorination by-products appeared to be low as the maximum total trihalomethane concentration detected was 432 μg/L.

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Comparison of energy consumption for position controlled PMSM using various energy near-optimal control techniques

2014 ELEKTRO ◽

10.1109/elektro.2014.6848900 ◽

2014 ◽

Cited By ~ 1

Author(s):

P. Butko ◽

T. Fedor ◽

J. Vittek

Keyword(s):

Optimal Control ◽

Energy Consumption ◽

Control Techniques

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Performance improvement of water-cooled screw chiller under part load operation conditions by the paralleling throttle mechanism

Thermal Science ◽

10.2298/tsci171011043n ◽

2018 ◽

Vol 22 (Suppl. 2) ◽

pp. 585-596

Author(s):

Long Ni ◽

Jijin Wang ◽

Dehu Qv ◽

Qiang Cai ◽

Yang Yao

Keyword(s):

Energy Consumption ◽

Operating Conditions ◽

Environmental Benefits ◽

Coefficient Of Performance ◽

Part Load ◽

Operation Conditions ◽

Industrial Buildings ◽

Discharge Temperature ◽

Access Mode ◽

Load State

Currently, water-cooled screw chiller is widely applied in commercial and industrial buildings, and the energy consumption of water chiller even could cover 70% of air-conditioning energy consumption in the most adverse operating conditions. Moreover, a number of chillers are running at a low rate under part-load state. In order to reduce the energy consumption of water-cooled screw chillers under part-load state, the paper presents the paralleling throttle mechanism. Through experimental study, under part-load state, it can be found that the by-pass tube diameter ?16 has the most positive effect on the performance of water-cooled screw chiller in four by-pass tube diameters. The oblique access mode is better than the vertical access mode, while the spiral access mode has little influence on the chiller performance. Because of paralleling throttle using, the exergetic loss of the evaporator and chiller is able to be reduced by 3.4%-15.5% and 0-6.7%, respectively. Meanwhile, the coefficient of performance of chiller can be enhanced by 0.2%-1.6%, and discharge temperature can be reduced by 0.4-2.7?C. In addition, the economic and environmental benefits of the advanced water-cooled screw chiller are more evident than the conventional water-cooled screw chiller's.

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