Fuel Optimal Controller for Hydrostatic Drives: A Simulation Study and Model Validation

2014 ◽  
Author(s):  
Joni Backas ◽  
Reza Ghabcheloo ◽  
Mika Hyvönen ◽  
Kalevi Huhtala
Keyword(s):  
Fuel Economy ◽  
High Efficiency ◽  
Fuel Efficiency ◽  
Optimal Controller ◽  
Hydraulic Pump ◽  
Research Platform ◽  
Variable Displacement ◽  
Semi Empirical ◽  
The Hill ◽  
Mobile Machine

This paper presents an optimal controller for fuel efficiency of a hydraulic mobile machine with hydrostatic drive (HSD). The solution is validated using a semi-empirical simulated research platform. The drive transmission of the machine includes one variable displacement hydraulic pump and four two-speed hub motors. There is no energy storage installed. Thus, the structure of the HSD and presented improvements in fuel economy are comparable to traditional machines. The optimal controller is compared to a baseline controller that intuitively keeps the components at their high efficiency regions. In simulated hill tests, fuel economy was improved by up to 25.9 % depending on the slope of the hill and velocity reference.

Design and Testing of an Adjustable Linkage for a Variable Displacement Pump

2013 ◽  
Vol 5 (4) ◽  
Author(s):  
Shawn R. Wilhelm ◽  
James D. Van de Ven
Keyword(s):  
High Efficiency ◽  
Operating Conditions ◽  
The Novel ◽  
Hydraulic Pump ◽  
Low Friction ◽  
Transmission Angle ◽  
Displacement Pump ◽  
Order Of Magnitude ◽  
Variable Displacement ◽  
Design And Testing

A variable displacement hydraulic pump/motor with high efficiency at all operating conditions, including low displacement, is beneficial to multiple applications. Two major energy loss terms in conventional pumps are the friction and lubrication leakage in the kinematic joints. This paper presents the synthesis, analysis, and experimental validation of a variable displacement sixbar crank-rocker-slider mechanism that uses low friction pin joints instead of planar joints as seen in conventional variable pump/motor architectures. The novel linkage reaches true zero displacement with a constant top dead center position, further minimizing compressibility energy losses. The synthesis technique develops the range of motion for the base fourbar crank-rocker and creates a method of synthesizing the output slider dyad. It is shown that the mechanism can be optimized for minimum footprint and maximum stroke with a minimum base fourbar transmission angle of 30 deg and a resultant slider transmission angle of 52 deg. The synthesized linkage has a dimensionless stroke of 2.1 crank lengths with a variable timing ratio and velocity and acceleration profiles in the same order of magnitude as a comparable crank-slider mechanism. The kinematic and kinetic results from an experimental prototype linkage agree well with the model predictions.

Dynamic Model of a Novel Alternating Flow (AF) Hydraulic Pump

2017 ◽  
Author(s):  
Mengtang M. Li ◽  
Ryan Foss ◽  
Kim A. Stelson ◽  
James D. Van de Ven ◽  
Eric J. Barth
Keyword(s):  
Dynamic Model ◽  
High Efficiency ◽  
Check Valve ◽  
Viscous Friction ◽  
Operating Conditions ◽  
Hydraulic Systems ◽  
Displacement Control ◽  
Hydraulic Pump ◽  
Wide Range ◽  
Variable Displacement

High power density and good controllability are the most appealing characteristics that make hydraulic systems the best choice for many applications. Current state of the art hydraulic variable displacement pumps show high efficiency at high displacement while they have poor efficiencies at low displacement. This paper proposes a novel alternating flow (AF) variable displacement hydraulic pump to 1) eliminate metering losses by acting as a high-bandwidth pump for displacement control, 2) achieve high efficiency across a wide range of operating conditions and displacements, and 3) allow multiple units to be easily common-shaft mounted for a compact multi-actuator displacement control system from a single prime-mover. A dynamic model using first principles describes the cylinder pressure, flows between pairs of cylinders, and net inlet and outlet flows as a function of the pump’s phase shift angle. The model captures hydraulic check valve dynamics, the effective bulk modulus, leakage flows, and viscous friction. Piston kinematics and dynamics are discussed and energy loss models are presented and used to guide the design for a first prototype of the AF hydraulic pump. The paper presents simulation results from the model that offer an initial evaluation of this novel pump concept and potential applications.

Synthesis of a Variable Displacement Linkage for a Hydraulic Transformer

2011 ◽  
Author(s):  
Shawn R. Wilhelm ◽  
James D. Van de Ven
Keyword(s):  
High Efficiency ◽  
Storage System ◽  
Energy Storage System ◽  
Hydraulic Pump ◽  
Center Position ◽  
Displacement Pump ◽  
Variable Displacement ◽  
Synthesis Procedure ◽  
Stroke Mechanism ◽  
Liquid Piston

A hydraulic pump/motor with high efficiency at low displacements is required for a compressed air energy storage system that utilizes a liquid piston for near-isothermal compression. To meet this requirement, a variable displacement six-bar crank-rocker-slider mechanism, which goes to zero displacement with a constant top dead center position, has been designed. The synthesis technique presented in the paper develops the range of motion for the base four-bar crank-rocker, creates a method of synthesizing the output slider dyad, and analyzes the mechanisms performance in terms of transmission angles, slider stroke, mechanism footprint, and timing ratio. It is shown that slider transmission angles can be kept above 60 degrees and the base four-bar transmission angles can be controlled in order to improve overall efficiency. This synthesis procedure constructs a crank-rocker-slider mechanism for a variable displacement pump/motor that can be efficient throughout all displacements.

scholarly journals Drive cycle simulation of high efficiency combustions on fuel economy and exhaust properties in light-duty vehicles

2015 ◽  
Vol 157 ◽  
pp. 762-776 ◽  
Author(s):  
Zhiming Gao ◽  
Scott J. Curran ◽  
James E. Parks ◽  
David E. Smith ◽  
Robert M. Wagner ◽  
...  
Keyword(s):  
Fuel Economy ◽  
High Efficiency ◽  
Drive Cycle ◽  
Cycle Simulation ◽  
Light Duty ◽  
Light Duty Vehicles

High Efficiency Energy Conversion System Based on Modified Brayton Cycle

2005 ◽  
Author(s):  
Anatoli A. Borissov ◽  
Alexander A. Borissov ◽  
Kenneth K. Kramer
Keyword(s):  
High Efficiency ◽  
Fuel Efficiency ◽  
Brayton Cycle ◽  
Positive Displacement ◽  
Heat Engines ◽  
Current State ◽  
Technological Advances ◽  
First Results ◽  
Power Generation Systems ◽  
Vortex Combustion

Each year, the users in the U.S. alone spend over $100 billion on various type of engines to produce power — electrical, mechanical, and thermal. Despite technological advances, most all of these power generation systems have only been fine tuned: the engine efficiencies may have been improved slightly, but the underlying thermodynamic principles have not been modified to effect a drastic improvement. The result is that most engines in service today suffer from two major problems: low fuel efficiency and emission of high levels of polluting gases in the exhaust gases. The current state of propulsion engines or distributed generation technologies using heat engines shows an average efficiency of between 20% and 40%. These low efficiencies in a high–cost energy market indicate a great need for more efficient technologies. This paper describes a new method of achieving a very high efficiency, namely optimizing every stage of the thermodynamic process-Brayton cycle. Two modified processes, such as isothermal compression and recuperation, add about 35% efficiency to the conventional Brayton cycle, making 60% efficiency for modified Brayton cycle. By utilizing a positive displacement compressor and expander with a novel vortex combustion chamber and a vortex recuperator, high levels of efficiency with low emissions and noise are possible. The prototype engine with low RPM and high torque has been built which use continuous combustion of different fuels under a constant pressure. First results of the engine’s components testing are presented.

Investigation of Hybrid Fuel Cell (HFC) Technology Applications on the Future Passenger Railroad Transportation

Joint Rail ◽  
2003 ◽  
Author(s):  
H. Moghbelli ◽  
Y. Gao ◽  
R. Langari ◽  
M. Ehsani
Keyword(s):  
Fuel Consumption ◽  
Fuel Economy ◽  
High Speed ◽  
High Efficiency ◽  
New Technologies ◽  
Positive Impact ◽  
Weak Link ◽  
Transportation System ◽  
Production Costs ◽  
Passenger Railroad

Due to the consideration of fragile security, and longer check-in times and inconveniences due to increased air travel security examination since September 11th 2001, more and more people have turn to ground transportation. Unfortunately, the inefficient, environment-unfriendly and unsafe passenger cars and buses are the only choices available for middle distance trips. Development of high efficiency, clean and high speed railroad passenger transportation system has become more necessary to overcome this weak link. In this paper, the applicability of hybrid drive train technologies for middle-distance passenger train locomotives will be investigated. A systematic design of the diesel based hybrid locomotive helps to increase efficiency, improve fuel economy, reduce emissions and also reduce mass production costs. Furthermore, professional management and maintenance of railroad train locomotives make such new technologies more practical than for road vehicles. The success of such transportation system will have a great positive impact on our social activities, quality of life, energy supply, environment and economy. A diesel based hybrid electric locomotive (HEL) with batteries or an ultracapacitor is an option to reduce fuel consumption and emissions and provide better performance and fuel economy. The reduced fuel consumption helps reduce the amount of pollutants released. Engineering estimation indicate that emissions will be reduced by 70% and fuel efficiency will be increased by at least 30% in hybrid locomotives.

scholarly journals Reduction of Aerodynamic Drag of Heavy Vehicles using CFD

2021 ◽  
Vol 9 (8) ◽  
pp. 2670-2678
Author(s):  
Priyank Kothari
Keyword(s):  
Fuel Economy ◽  
Aerodynamic Drag ◽  
Fuel Efficiency ◽  
Heavy Vehicles ◽  
Heavy Trucks ◽  
Air Resistance

Abstract: Aerodynamic drag is the force that opposes an object’s motion. When a vehicle no matter the size, is designed to allow air to move fluidly over its body, aerodynamic drag will have less of an impact on its performance and fuel economy. Heavy trucks burn a significant amount of fuel as to overcome the air resistance. More than 50% of an 18-wheeler’s fuel is spent reducing aerodynamic drag on the highways. Keywords: Aerodynamics, Heavy vehicles, ANSYS, Aerodynamic Drag, Fuel efficiency.

scholarly journals Experimental Analysis of Calculation of Fuel Consumption Rate by On-Road Mileage in a 2.0 L Gasoline-Fueled Passenger Vehicle

2018 ◽  
Vol 8 (12) ◽  
pp. 2390 ◽  
Author(s):  
Jaehyuk Lim ◽  
Yumin Lee ◽  
Kiho Kim ◽  
Jinwook Lee
Keyword(s):  
Fuel Consumption ◽  
Fuel Economy ◽  
Fuel Efficiency ◽  
Co2 Concentration ◽  
The United States ◽  
Traffic Conditions ◽  
Fuel Consumption Rate ◽  
Driving Cycles ◽  
The Difference ◽  
Consumption Value

The five-driving test mode is vehicle driving cycles made by the Environment Protection Association (EPA) in the United States of America (U.S.A.) to fully reflect actual driving environments. Recently, fuel consumption value calculated from the adjusted fuel consumption formula has been more effective in reducing the difference from that experienced in real-world driving conditions, than the official fuel efficiency equation used in the past that only considered the driving environment included in FTP and HWFET cycles. There are many factors that bring about divergence between official fuel consumption and that experienced by drivers, such as driving pattern behavior, accumulated mileage, driving environment, and traffic conditions. In this study, we focused on the factor of causing change of fuel efficiency value, calculated according to how many environmental conditions that appear on the real-road are considered, in producing the fuel consumption formula, and that of the vehicle’s accumulated mileage in a 2.0 L gasoline-fueled vehicle. So, the goals of this research are divided into four major areas to investigate divergence in fuel efficiency obtained from different equations, and what factors and how much CO2 and CO emissions that are closely correlated to fuel efficiency change, depending on the cumulative mileage of the vehicle. First, the fuel consumption value calculated from the non-adjusted formula, was compared with that calculated from the corrected fuel consumption formula. Also, how much CO2 concentration levels change as measured during each of the three driving cycles was analyzed as the vehicle ages. In addition, since the US06 driving cycle is divided into city mode and highway mode, how much CO2 and CO production levels change as the engine ages during acceleration periods in each mode was investigated. Finally, the empirical formula was constructed using fuel economy values obtained when the test vehicle reached 6500 km, 15,000 km, and 30,000 km cumulative mileage, to predict how much fuel consumption of city and highway would worsen, when mileage of the vehicle is increased further. When cumulative mileage values set in this study were reached, experiments were performed by placing the vehicle on a chassis dynamometer, in compliance with the carbon balance method. A key result of this study is that fuel economy is affected by various fuel consumption formula, as well as by aging of the engine. In particular, with aging aspects, the effect of an aging engine on fuel efficiency is insignificant, depending on the load and driving situation.

scholarly journals Minimum Energy Management Strategy of Equivalent Fuel Consumption of Hybrid Electric Vehicle Based on Improved Global Optimization Equivalent Factor

Energies ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 2076 ◽  
Author(s):  
Xixue Liu ◽  
Datong Qin ◽  
Shaoqian Wang
Keyword(s):  
Energy Management ◽  
Fuel Economy ◽  
Hybrid Electric Vehicle ◽  
High Efficiency ◽  
Energy Management Strategy ◽  
Target Value ◽  
Equivalent Fuel ◽  
Equivalent Factor ◽  
Equivalent Fuel Consumption ◽  
Engine Operating Point

A parallel hybrid electric vehicle (PHEV) is used to investigate the fuel economy effect of the equivalent fuel consumption minimization strategy (ECMS) with the equivalent factor as the core, where the equivalent factor is the conversion coefficient between fuel thermal energy and electric energy. In the conventional ECMS strategy, the battery cannot continue to discharge when the state of charge (SOC) is lower than the target value. At this time, the motor mainly works in the battery charging mode, making it difficult to adjust the engine operating point to the high-efficiency zone during the acceleration process. To address this problem, a relationship model of the battery SOC, vehicle acceleration a, and equivalent factor S was established. When the battery SOC is lower than the target value and the vehicle demand torque is high, which makes the engine operating point deviate from the high-efficiency zone, the time that the motor spends in the power generation mode during the driving process is reduced. This enables the motor to drive the vehicle at the appropriate time to reduce the engine output torque, and helps the engine operate in the high-efficiency zone. The correction function under US06 condition was optimized by genetic algorithm (GA). The best equivalent factor MAP was obtained with acceleration a and battery SOC as independent variables, and the improved global optimal equivalent factor of ECMS was established and simulated offline. Simulation results show that compared with conventional ECMS, the battery still has positive power output even when the SOC is less than the target value. The SOC is close to the target value after the cycle condition, and fuel economy improved by 1.88%; compared with the rule-based energy management control strategies, fuel economy improved by 10.17%. These results indicate the effectiveness of the proposed energy management strategy.

Sign in / Sign up

Export Citation Format

Share Document