Model Predictive Engine Speed Control for Transmissions With Dog Clutches

Author(s):  
Qilun Zhu ◽  
Robert Prucka ◽  
Michael Prucka ◽  
Hussein Dourra

The need for cost-effective fuel economy improvements has driven the introduction of automatic transmissions with an increasing number of gear ratios. Incorporation of interlocking dog clutches in these transmissions decreases package space and increases efficiency, as compared to conventional dry or wet clutches. Unlike friction-based clutches, interlocking dog clutches require very precise rotational speed matching prior to engagement. Precise engine speed control is, therefore, critical to maintaining high shift quality. This research focuses on controlling the engine speed during a gearshift period by manipulating throttle position and combustion phasing. Model predictive control (MPC) is advantageous in this application since the speed profile of a future prediction horizon is known with relatively high confidence. The MPC can find the optimal control actions to achieve the designated speed target without invoking unnecessary actuator manipulation and violating hardware and combustion constraints. This research utilizes linear parameter varying (LPV) MPC to control the engine speed during the gearshift period. Combustion stability constraints are considered with a control-oriented covariance of indicated mean effective pressure model (COV of IMEP). The proposed MPC engine speed controller is validated with a high-fidelity zero-dimensional engine model with crank angle resolution. Four case studies, based on simulation, investigate the impact of different MPC design parameters. They also demonstrate that the proposed MPC engine controller successfully achieves the speed reference tracking objective while considering combustion variation constraints.

Author(s):  
Qilun Zhu ◽  
Robert Prucka ◽  
Michael Prucka ◽  
Hussein Dourra

The need for cost-effective fuel economy improvements has driven the introduction of automatic transmissions with an increasing number of gear ratios. Incorporation of interlocking dog clutches in these transmissions decreases package space and increases efficiency, as compared to conventional dry or wet clutches. Unlike friction based clutches, interlocking dog clutches require very precise rotational speed matching prior to engagement. Precise engine speed control is therefore critical to maintaining high shift quality. This research focuses on controlling the engine speed during a gearshift period by manipulating throttle position and combustion phasing. Model predictive control (MPC) is advantageous in this application since the speed profile of a future prediction horizon is known with relatively high confidence. The MPC can find the optimal control actions to achieve the designated speed target without invoking unnecessary actuator manipulation and violating hardware and combustion constraints. This research utilizes linear parameter varying (LPV) MPC to control the engine speed during the gearshift period. Combustion stability constraints are considered with a control oriented covariance of indicated mean effective pressure model (COV of IMEP). The proposed MPC engine speed controller is validated with a high-fidelity 0-dimensional engine model with crank angle resolution. Four case studies, based on simulation, investigate the impact of different MPC design parameters. They also demonstrate that the proposed MPC engine controller successfully achieves the speed reference tracking objective while considering combustion variation constraints.


Author(s):  
Kazuaki Yazawa ◽  
Yee Rui Koh ◽  
Ali Shakouri

Thermoelectric (TE) generators have a potential advantage of the wide applicable temperature range by a proper selection of materials. In contrast, a steam turbine (ST) as a Rankine cycle thermodynamic generator is limited up to more or less 630 °C for the heat source. Unlike typical waste energy recovery systems, we propose a combined system placing a TE generator on top of a ST Rankine cycle generator. This system produces an additional power from the same energy source comparing to a stand-alone steam turbine system. Fuel efficiency is essential both for the economic efficiency and the ecological friendliness, especially for the global warming concern on the carbon dioxide (CO2) emission. We report our study of the overall performance of the combined system with primarily focusing on the design parameters of thermoelectric generators. The steam temperature connecting two individual generators gives a trade-off in the system design. Too much lower the temperature reduces the ST performance and too much higher the temperature reduces the temperature difference across the TE generator hence reduces the TE performance. Based on the analytic modeling, the optimum steam temperature to be designed is found near at the maximum power design of TE generator. This optimum point changes depending on the hours-of-operation. It is because the energy conversion efficiency directly connects to the fuel consumption rate. As the result, physical upper-limit temperature of steam for ST appeared to provide the best fuel economy. We also investigated the impact of improving the figure-of-merit (ZT) of TE materials. As like generic TE engines, reduction of thermal conductivity is the most influential parameter for improvement. We also discuss the cost-performance. The combined system provides the payback per power output at the initial and also provides the significantly better energy economy [$/KWh].


Author(s):  
David Cimba ◽  
Kyle Gilbert ◽  
John Wagner

Sport utility and light-duty commercial vehicles exhibit a higher propensity for rollover during aggressive driving maneuvers, emergency scenarios, and degraded environmental conditions. A variety of strategies have been proposed to reduce vehicle body roll including active suspensions, comprehensive yaw stability systems, and active torsion bars. The active torsion bar systems have recently gained popularity due to their cost effective design and adaptability to existing chassis systems. However, the development of new control algorithms, design of subsystem components, and the evaluation of parameter sensitivity via testing a full scale vehicle is not always practical due to cost and safety concerns. Thus, a modular simulation tool and bench top testing environment is required to facilitate design and performance studies. In this paper, a series of mathematical models will be introduced to describe the vehicle dynamics and the roll prevention system. Representative numerical results are discussed to investigate a vehicle’s transient response with and without an active torsion bar system, as well as the impact of torsion bar and hydraulic component design parameters. Finally, a hardware in-the-loop test environment will be presented.


Author(s):  
A. S. Paimon ◽  
S. Rajoo ◽  
W. Jazair ◽  
M. A. Abas ◽  
Z. H. Che Daud

This paper investigates the effect of valve deactivation (VDA) on idling performance in port fuel injection (PFI) engine. The test was conducted on 1.6L, 4-cylinder engine with PFI configuration. One of the two intake valves in each cylinder was deactivated (zero lift on deactivated port) and fuel injector was modified to only provide fuel spray on the active intake port. In-cylinder pressure was recorded by the combustion analyzer in order to measure and analyze the combustion characteristics. From the test, there are up to 6% of fuel consumption improvements across all the test conditions. Better combustion stability is achieved at very low idling speed (throttle position, TP = 2%) as a lower coefficient of variation of engine speed (COVrpm) and coefficient of variation indicated mean effective pressure (COVimep) were recorded. Increased intake velocity and swirl flow in the VDA strategy creates more turbulence intensity causing higher heat release rate and faster combustion. However, there is no significant difference in the pumping work during the intake cycle but there is extra pumping work recorded towards the end of expansion stroke due to the very early end of combustion. Therefore, valve deactivation strategy provides limited positive improvement to the idling performance in PFI engine.


Author(s):  
Jacob Ahles ◽  
Kyle Price ◽  
Brian Eggart ◽  
Scott A. Miers ◽  
Andrew Wiegand ◽  
...  

Two-stroke engines are capable of providing very high power density levels in a cost effective, easy-to-maintain package. They are, however, typically susceptible to higher levels of hydrocarbon emissions, lower durability, and a shorter lifecycle when compared to four-stroke engines. These detriments are easily overlooked in some military applications where power density is paramount, but most commercial two-stroke engines require specialized consumable lubricant. Typical military applications strive to minimize their logistics “trails,” which includes minimizing the variety of fluids they require. As a result, there has been very limited success in fielding small two-stroke engines for military use. As a preliminary study, MIL-PRF-2104K Single Common Powertrain Lubricant (SCPL, a four-stroke heavy diesel engine oil) was utilized as the consumable lubricant (in place of conventional two-stroke oil) in a liquid-cooled, semi-direct fuel injected, spark-ignition, two-stroke engine. Empirical data was collected to study the impact of the oil on deposit build-up, power, wear, combustion stability, and fuel conversion efficiency. Over 147 hours of operation were logged and analyzed. The performance of the engine on SCPL was consistent with conventional two-stroke oil and showed no degradation over the test duration. Brake specific fuel consumption was not negatively impacted with SCPL. Increased deposit build-up in the exhaust ports and on the spark plugs were the primary negative impacts of the SCPL oil. Spark plugs with hotter classifications and modification of the oiling rate resulted in a reduction of soot accumulation and spark plug fouling.


1997 ◽  
Vol 483 ◽  
Author(s):  
B. Fatemizadehl ◽  
Y. Granik

AbstractThis paper presents a methodology to optimize the design of different types of IGBT using TWB (TMA WorkBench). Using RSM (Response Surface Modeling) and DOE (Design of Experiment) in TWB we have developed a methodology, which can be applied to explore the impact of design modifications on the speed improvement and study the trade-off between speed, on-resistance, and breakdown voltage of IGBT. This method is a rapid and cost-effective approach for studying design alternatives. Two-dimensional simulations were used to determine the influence of technology and design parameter on device characteristics.


2018 ◽  
Vol 2018 ◽  
pp. 1-18 ◽  
Author(s):  
Runzhi Wang ◽  
Xuemin Li ◽  
Jiguang Zhang ◽  
Jian Zhang ◽  
Wenhui Li ◽  
...  

In this paper, a compound control scheme with linear active disturbance rejection control (LADRC) and nonlinear active disturbance rejection control (NLADRC) is designed to stabilize the speed control system of the marine engine. To deal with the high nonlinearity and the complex disturbance and noise conditions in marine engines, the advantages of both LADRC and NLADRC are employed. As the extended state observer (ESO) is affected severely by the inherent characteristics (cyclic speed fluctuation, cylinder-to-cylinder deviations, etc.) of the reciprocating engines, a cycle-detailed hybrid nonlinear engine model is adopted to analyze the impact of such characteristics. Hence, the controller can be evaluated based on the modified engine model to achieve more reliable performance. Considering the mentioned natural properties in reciprocating engines, the parameters of linear ESO (LESO), nonlinear ESO (NLESO), and the switching strategy between LADRC and NLADRC are designed. Finally, various comparative simulations are carried out to show the effectiveness of the proposed control scheme and the superiority of switching strategy. The simulation results demonstrate that the proposed control scheme has prominent control effects both under the speed tracking mode and the condition with different types and levels of load disturbance. This study also reveals that when ADRC related approaches are employed to the reciprocating engine, the impact of the inherent characteristics of such engine on the ESO should be considered well.


TAPPI Journal ◽  
2018 ◽  
Vol 17 (09) ◽  
pp. 519-532 ◽  
Author(s):  
Mark Crisp ◽  
Richard Riehle

Polyaminopolyamide-epichlorohydrin (PAE) resins are the predominant commercial products used to manufacture wet-strengthened paper products for grades requiring wet-strength permanence. Since their development in the late 1950s, the first generation (G1) resins have proven to be one of the most cost-effective technologies available to provide wet strength to paper. Throughout the past three decades, regulatory directives and sustainability initiatives from various organizations have driven the development of cleaner and safer PAE resins and paper products. Early efforts in this area focused on improving worker safety and reducing the impact of PAE resins on the environment. These efforts led to the development of resins containing significantly reduced levels of 1,3-dichloro-2-propanol (1,3-DCP) and 3-monochloropropane-1,2-diol (3-MCPD), potentially carcinogenic byproducts formed during the manufacturing process of PAE resins. As the levels of these byproducts decreased, the environmental, health, and safety (EH&S) profile of PAE resins and paper products improved. Recent initiatives from major retailers are focusing on product ingredient transparency and quality, thus encouraging the development of safer product formulations while maintaining performance. PAE resin research over the past 20 years has been directed toward regulatory requirements to improve consumer safety and minimize exposure to potentially carcinogenic materials found in various paper products. One of the best known regulatory requirements is the recommendations of the German Federal Institute for Risk Assessment (BfR), which defines the levels of 1,3-DCP and 3-MCPD that can be extracted by water from various food contact grades of paper. These criteria led to the development of third generation (G3) products that contain very low levels of 1,3-DCP (typically <10 parts per million in the as-received/delivered resin). This paper outlines the PAE resin chemical contributors to adsorbable organic halogens and 3-MCPD in paper and provides recommendations for the use of each PAE resin product generation (G1, G1.5, G2, G2.5, and G3).


Author(s):  
Nikolay S. Shulaev ◽  
◽  
Valeriya V. Pryanichnikova ◽  
Ramil R. Kadyrov ◽  
Inna V. Ovsyannikova ◽  
...  

The most essential scientifific and practical task in the area of ecological safety of pipelines operation is the development and improvement of methods of purifification and restoration of oil-contaminated soils. One of the most effificient and cost effective methods is electrochemical purifification, that does not require the use of expensive chemical reagents and soil excavation. However, the consideration of non-uniform contamination of various soil sections is required. The article examines the features of the organization and technological infrastructure for electrochemical purifification of non-uniformly contaminated soils when using a single electrical energy source, a method for calculating the design parameters of the corresponding installation is proposed. Effificient purifification of non-uniformly contaminated soil when using a specifified voltage is possible through the use of different-sized electrodes. For each soil type, the amount of transmitted electric charge required for soil purifification is determined by the concentration of the contaminant. Allocation of cathodes and anodes as parallel batteries and their connection using individual buses is an effective and energy-effificient solution, since an almost-uniform electric fifield is created in an inter-electrode space, thus allowing the reduction of the interelectrode resistance of the medium.


Author(s):  
Tochukwu Moses ◽  
David Heesom ◽  
David Oloke ◽  
Martin Crouch

The UK Construction Industry through its Government Construction Strategy has recently been mandated to implement Level 2 Building Information Modelling (BIM) on public sector projects. This move, along with other initiatives is key to driving a requirement for 25% cost reduction (establishing the most cost-effective means) on. Other key deliverables within the strategy include reduction in overall project time, early contractor involvement, improved sustainability and enhanced product quality. Collaboration and integrated project delivery is central to the level 2 implementation strategy yet the key protocols or standards relative to cost within BIM processes is not well defined. As offsite construction becomes more prolific within the UK construction sector, this construction approach coupled with BIM, particularly 5D automated quantification process, and early contractor involvement provides significant opportunities for the sector to meet government targets. Early contractor involvement is supported by both the industry and the successive Governments as a credible means to avoid and manage project risks, encourage innovation and value add, making cost and project time predictable, and improving outcomes. The contractor is seen as an expert in construction and could be counter intuitive to exclude such valuable expertise from the pre-construction phase especially with the BIM intent of äóÖbuild it twiceäó», once virtually and once physically. In particular when offsite construction is used, the contractoräó»s construction expertise should be leveraged for the virtual build in BIM-designed projects to ensure a fully streamlined process. Building in a layer of automated costing through 5D BIM will bring about a more robust method of quantification and can help to deliver the 25% reduction in overall cost of a project. Using a literature review and a case study, this paper will look into the benefits of Early Contractor Involvement (ECI) and the impact of 5D BIM on the offsite construction process.


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