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Due to the growing emergence of vehicle electrification, agricultural tractor developers are launching hybrid powertrains in which energy management strategy (EMS) assumes a prominent role. This work mainly aims at developing an EMS for a plug‐in hybrid electric tractor (PHET) to minimise fuel consumption and increase the operating range. The developed off‐road PHET power sources are composed of a biogas‐fuelled Internal Combustion Engine Generator (Bio‐Gen), a photovoltaic system, and a battery pack. To control the power flow among different sources, a two‐layer EMS is formulated. In this regard, initially, the farm operating mode is recognised by means of classification of a working cycle's features. Then, a control strategy based on a multi‐mode fuzzy logic controller (MFLC) is employed to manage the power flow. At each sequence, the classifier identifies the farm operation condition and accordingly activates the relative mode of the MFLC to meet the requested power from the Bio‐Gen. The performance of the proposed EMS has been evaluated based on three real‐world typical agricultural working cycles. The results demonstrate the successful performance of the proposed intelligent EMS under farm conditions by maintaining the energy sources' operation in a high‐efficiency zone which can lead to the extension of the working range and decrease fuel consumption. [ABSTRACT FROM AUTHOR]

The problem of determining a shortest loop incident to each cell of a block layoutis considered. A compact formulation is developed for this problem and a relativelysimple algorithm is presented. It is shown that instances containing up to60 cells can be solved optimally by using a commercial integer linear programmingsolver embedded within an iterative scheme. [ABSTRACT FROM AUTHOR]

In the study of automated guided vehicles systems (AGVS), one assumption often made in the management of vehicles is the existence of either home locations or a circulatory loop to buffer or hold idle vehicles. A review of AGVS literature reveals that different researchers pursue one idle vehicle management policy or the other. In some studies, idle vehicles are assumed to circulate in some loops in the system while others assume they are routed to some dwell point locations where they are held until they are reassigned. When the dwell point option is implemented, different strategies for implementation are also available. However, what is generally lacking in references to dwell point strategies are the techniques for selecting the optimal or best dwell points for a given facility. In this study, the problem of dwell point or home location specification is addressed. The problem was modelled mathematically to determine the optimal home locations. The emphasis in the paper is on a unidirectional AGVS guide path. The criterion of optimization employed is the minimization of the system response time to vehicle demand points when dispatched from home locations. Solution methodologies are presented and example problems solved to illustrate the applications of the models presented. [ABSTRACT FROM AUTHOR]

The rationality of powertrain parameter design has a significant influence on the traction performance and economic performance of electric tractor. At present, researches on powertrain parameter design mainly focus on electric vehicles, and electric agricultural machinery draw much less attention. Therefore, a method of powertrain parameter matching and optimization design for electric tractor was proposed in this paper, which was based on dual-motor coupling drive mode. The particle swarm optimization (PSO) algorithm based on mixed penalty function was used to solve the optimization problems. Parameter optimization design was programmed using MATLAB. A simulation dynamic model with optimization design variables of electric tractor powertrain was established based on MATLAB/Simulink. Compared with the simulation results before optimization, the objective functions had got optimized and the traction performance of electric tractor had been improved, which indicated the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

It is difficult to make full use of the electrical energy of the power battery for extended-range electric tractors because the battery's state of charge may be relatively high at the end of the running mileage. To address this situation, this paper aimed to study the control parameter adjustment in relation to the power battery's electrical consumption and the diesel engine's fuel consumption energy management strategy. Based on the AVL-Cruise simulation platform, the vehicle model of the tractor was established, and the control module of AVL-Cruise was used to compile the energy management strategy. In order to verify the superiority of the proposed strategy, the contrast strategy was employed in terms of the diesel engine start and stop control plus fixed point energy management strategy (FPEMS). The applicability of the proposed strategy was tested through continuous transfer operation and the small area deep loosening operation. The simulation results show that the proposed strategy was of good applicability. Compared with the FPEMS, the fuel consumption reduced significantly, and the electrical consumption of the power battery increased obviously. [ABSTRACT FROM AUTHOR]

This paper presents the main applications of electric vehicles in rural areas, pointing out the trends and challenges for the future. Technological conditions and difficulties faced by the industry for a wide dissemination of this technology are discussed. The paper described the main researches with proposals to overcome the problems of implementing electric tractors, as supply and electricity storage. Technical and economic comparisons between conventional internal combustion tractors and electric tractors are also presented and discussed. The paper showed the existence of barriers to the implementation of electric vehicles in rural areas, as well as the need for batteries technological evolution, which have high costs and for that reason they are very heavy for these purposes, but there are already systems that can be applied to minimize dependence of fossil fuels in this sector and increase the use of sustainable energy. [ABSTRACT FROM AUTHOR]

Concerns regarding the fuel costs and climate change impacts associated with petroleum combustion are among the main driving factors for the adoption of electric vehicles. Future commercial delivery truck fleets may include Battery Electric Vehicles (BEVs) and Extended Range Electric Vehicles (EREVs); in addition to savings on fuel and maintenance costs, the introduction of these grid accessible electric vehicles will also provide fleet owners with possible Vehicle to Grid (V2G) opportunities. This study investigates the potential net present revenues and greenhouse gas (GHG) emission mitigation of V2G regulation services provided by electric trucks in a typical fleet. The total cost of ownership and the life-cycle GHG emissions of electric trucks are also analyzed and compared to those of traditional diesel trucks. To account for uncertainties, possible ranges for key parameters are considered instead of only considering fixed single data values for each parameter. The results of this research indicate that providing V2G regulation services for electric trucks could yield considerable additional revenues ($20,000–50,000) and significant GHG emission savings (approximately 300 ton CO 2 ) compared to conventional diesel trucks. [ABSTRACT FROM AUTHOR]

In order to improve the electrical conversion efficiency of an electric tractor motor, a load torque based control strategy (LTCS) is designed in this paper by using a particle swarm optimization algorithm (PSO). By mathematically modeling electric-mechanical performance and theoretical energy waste of the electric motor, as well as the transmission characteristics of the drivetrain, the objective function, control relationship, and analytical platform are established. Torque and rotation speed of the motor’s output shaft are defined as manipulated variables. LTCS searches the working points corresponding to the best energy conversion efficiency via PSO to control the running status of the electric motor and uses logic and fuzzy rules to fit the search initialization for load torque fluctuation. After using different plowing forces to imitate all the common tillage forces, the simulation of traction experiment is conducted, which proves that LTCS can make the tractor use electrical power efficiently and maintain agricultural applicability on farmland conditions. It provides a novel method of fabricating a more efficient electric motor used in the traction of an off-road vehicle. [ABSTRACT FROM AUTHOR]

For the first time, a manufacturer has developed electrically powered LHD loaders and mining trucks (dump trucks) up to 50 tonnes payload for the non-firedamp-endangered mining field. These developments were based on the requirements signalled by numerous mines around the world. In comparison with diesel-powered vehicles, electrically powered mining trucks can be used at significantly higher speeds, especially in the ramps during loaded uphill travel. This can be clearly seen in the extraction costs. With electric operation, significant cost savings can be made in ventilation, and the working conditions for the machine operators can be significantly improved. There has never been an interaction between LHD loaders and mining trucks with machines of this size, both electrically powered, up to the present time. In many mines around the world, this technique will be instrumental in future in supporting the steps necessary for economic recovery at greater depths. Erstmalig wurden von einem Hersteller elektrisch betriebene LHD-Fahrlader und Minetrucks (Muldenkipper) bis 50 t Nutzlast für den nicht schlagwetter-gefährdeten Bergbaubereich entwickelt. Diese Entwicklungen basierten auf Bedarfsmeldungen von zahlreichen Bergwerken weltweit. Elektrisch betriebene Minetrucks können im Vergleich zu dieselbetriebenen Fahrzeugen mit deutlich höheren Geschwindigkeiten besonders in den Rampen bei der beladenen Bergfahrt eingesetzt werden. Dieses lässt sich in den Gewinnungskosten signifikant darstellen. Mit dem elektrischen Betrieb lassen sich auch erhebliche Kosten in der Bewetterung einsparen und die Arbeitsplatzbedingungen für die Maschinenfahrer deutlich verbessern. Ein Zusammenspiel von LHD-Fahrladern und Minetrucks, beide elektrisch angetrieben, hat es bis zum heutigen Zeitpunkt in dieser Gerätegröße noch nicht gegeben. Diese Technik wird zukünftig in zahlreichen Bergwerken weltweit die erforderlichen Schritte für die wirtschaftliche Gewinnung in größeren Teufen maßgeblich unterstützen. [ABSTRACT FROM AUTHOR]

This paper presents a fast switching direct torque control (FS-DTC) using only a single DC-link current sensor. In FS-DTC, six new active voltage complex space vectors (CSVs) are synthesized by the conventional active voltage space vectors (SVs). The corresponding sectors are rotated in the anticlockwise direction by 30 degrees. A selection table is defined to select the CSVs. Based on the "Different Phase Mode", the output sequence of the selected CSV is optimized. Accordingly, a reconstruction method is proposed to acquire the phase currents. The core of the FS-DTC is that all of the three phase currents can be reliably reconstructed during every two sampling periods, which is the result of the fast switching between different phases. The errors between the reconstructed and actual currents are strictly limited in one sampling period. The FS-DTC has the advantages of the standard DTC scheme such as simple structure, quick torque response and robustness. As can be seen in the analysis, the FS-DTC can be thought of as an equivalent standard DTC scheme with 86.6% of the maximum speed, 173.2% of the torque ripple, and 115% of the response time of the torque. Based on a dSPACE DS1103 controller, the FS-DTC is implemented in an induction machine drive system. The results verify the effectiveness of the FS-DTC. [ABSTRACT FROM AUTHOR]

It is well known that control systems are the core of electronic differential systems (EDSs) in electric vehicles (EVs)/hybrid HEVs (HEVs). However, conventional closed-loop control architectures do not completely match the needed ability to reject noises/disturbances, especially regarding the input acceleration signal incoming from the driver's commands, which makes the EDS (in this case) ineffective. Due to this, in this paper, a novel EDS control architecture is proposed to offer a new approach for the traction system that can be used with a great variety of controllers (e.g., classic, artificial intelligence (AI)-based, and modern/robust theory). In addition to this, a modified proportional–integral derivative (PID) controller, an AI-based neuro-fuzzy controller, and a robust optimal H\infty controller were designed and evaluated to observe and evaluate the versatility of the novel architecture. Kinematic and dynamic models of the vehicle are briefly introduced. Then, simulated and experimental results were presented and discussed. A Hybrid Electric Vehicle in Low Scale (HELVIS)-Sim simulation environment was employed to the preliminary analysis of the proposed EDS architecture. Later, the EDS itself was embedded in a dSpace 1103 high-performance interface board so that real-time control of the rear wheels of the HELVIS platform was successfully achieved. [ABSTRACT FROM PUBLISHER]

Abstract: Hybrid electric vehicles require an algorithm that controls the power split between the internal combustion engine and electric machine(s), and the opening and closing of the clutch. Optimal control theory is applied to derive a methodology for a real-time optimal-control-based power split algorithm. The presented strategy is adaptive for vehicle mass and road elevation, and is implemented on a standard Electronic Control Unit of a parallel hybrid electric truck. The implemented strategy is experimentally validated on a chassis dynamo meter. The fuel consumption is measured on 12 different trajectories and compared with a heuristic and a non-hybrid strategy. The optimal control strategy has a fuel consumption lower (up to 3%) than the heuristic strategy on all trajectories that are evaluated, except one. Compared to the non-hybrid strategy the fuel consumption reduction ranged from 7% to 16%. [Copyright &y& Elsevier]

Abstract: The most well-known reason of global warming is equivalent carbon dioxide (CO2equ) emitted from fossil fuels combustion in on-road and off-road vehicles. An appreciable portion of off-road pollution is allocated to farm implements. All cited studies have shown that renewable based electric vehicles (EVs) decrease petroleum consumption and consequently reduce criteria emissions under nearly all circumstances. Considering this, a Solar Assist Plug-in Hybrid electric Tractor (SAPHT) was designed, constructed and evaluated. This research evaluated the life cycle analysis of SAPHT project and compared the results with that of an internal combustion engine tractor (ICET). The life cycle was analyzed based on economical cost and environmental emissions. The externality of environmental pollutions was calculated to derive the life-cycle costs (LCC). The results showed that substituting each ICET by SAPHT can prevent 14ton CO2equ emission to atmosphere annually. Also it prevents a high volume of other emissions such as CO, NO x and PM10 entering the atmosphere. LCC assessment emphasizes on economical effectiveness of SAPHT rather than ICET at any diesel fuel price, therefore, increasing fuel unit prices leads to more effectiveness. It is concluded that levelized cost of energy (LCE) in €/kWh for ICET is almost twice as that of SAPHT. Some of these advantages for SAPHT are offset in part by high purchase costs, heavy and massive batteries and low operating range. [ABSTRACT FROM AUTHOR]

Significant unproductive and costly waiting occurs during AGV (Automated Guided Vehicle) use, both under the CC (Container Crane) and in the blocks compared to that of a manual yard tractor. A possible solution to this problem is that, in the design of ACT (Automated Container Terminals), ALV (Automated Lifting Vehicles), which can load and unload their own containers, be considered as an alternative. In this paper, the objective is to analyze how increases in the use of ALVs rather than AGVs affects the productivity of ACTs. We derived four inferences regarding the cycle time of vehicles and verified their validity in a simulation. A simulation model of an ACT with perpendicular layout was developed and is described in this paper. From the results of the simulation analysis, we determined the savings effect by cycle time and the required number of vehicles. We demonstrated that the ALV is superior to the AGV in both productivity and efficiency principally because the ALV eliminates the waiting time in the buffer zone. [ABSTRACT FROM AUTHOR]

Traces the history of electric truck in United States cities during the first quarter of the 20th century. Overview of early commercial motor vehicles; Evolution of the separate spheres for horse-drawn and motorized commercial vehicles; Reasons for the failure of the electric truck to make greater inroads into major urban markets once the improvements were in place.

In this paper, we address a difficult combinatorial problem that arises in designing fixed-path material handling systems, where handling occurs over a pre-defined and fixed route which connects various "sites" that are represented by a unique set of pickup and deposit points. Examples of such systems include power-and-free conveyors, monorails, in-floor towline conveyors, and automated guided vehicle systems. The objective of this study is to determine an efficient system design by simultaneously considering the configuration of the fixed path and the layout, i.e., the processor (or machine) assigned to each site. Past studies in this area have focused either on optimizing the path configuration for a given layout or on optimizing the layout for a simple path configuration. In this study, we show how simulated annealing can be applied to obtain good solutions to the problem when both the path configuration and the processor locations are determined concurrently. Since the above two problems are closely related, significant savings can be achieved by considering them simultaneously. [ABSTRACT FROM AUTHOR]