scholarly journals A novel predictive semi-physical feed-forward turbocharging system transient control strategy based on mean-value turbocharger model

2016 ◽  
Vol 18 (8) ◽  
pp. 765-775 ◽  
Author(s):  
Huayin Tang ◽  
Colin Copeland ◽  
Sam Akehurst ◽  
Chris Brace ◽  
Peter Davies ◽  
...  
Keyword(s):  
Control Strategy ◽  
Control Strategies ◽  
Mean Value ◽  
Variable Geometry ◽  
Gasoline Engines ◽  
Engine Model ◽  
Turbocharging System ◽  
Transient Control ◽  
Variable Geometry Turbine ◽  
The One

Variable geometry turbine is a technology that has been proven on diesel engines. However, despite the potential to further improve gasoline engines’ fuel economy and transient response using variable geometry turbine, controlling the variable geometry turbine during transients is challenging due to its highly non-linear behaviours especially on gasoline applications. After comparing three potential turbocharger transient control strategies, the one that predicts the turbine performances for a range of possible variable geometry turbine settings in advance was developed and validated using a high-fidelity engine model. The proposed control strategy is able to capture the complex transient behaviours and achieve the optimum variable geometry turbine trajectories. This improved the turbocharger response time by more than 14% compared with a conventional proportional–integral–derivative controller, which cannot achieve target turbocharge speed in all cases. Furthermore, the calibration effort required can be significantly reduced, offering significant benefits for powertrain developers. It is expected that the structure of this transient control strategy can also be applied to complex air-path systems.

Optimal Transient Control Trajectories in Diesel–Electric Systems—Part I: Modeling, Problem Formulation, and Engine Properties

2014 ◽  
Vol 137 (2) ◽  
Author(s):  
Martin Sivertsson ◽  
Lars Eriksson
Keyword(s):  
Optimal Control ◽  
Output Power ◽  
Control Strategies ◽  
Problem Formulation ◽  
Free Variable ◽  
Mean Value ◽  
Engine Model ◽  
Transient Control ◽  
Time Optimal ◽  
Power And Energy

A nonlinear four state-three input mean value engine model (MVEM), incorporating the important turbocharger dynamics, is used to study optimal control of a diesel–electric powertrain during transients. The optimization is conducted for the two criteria, minimum time and fuel, where both engine speed and engine power are considered free variables in the optimization. First, steps from idle to a target power are studied and for steps to higher powers the controls for both criteria follow a similar structure, dictated by the maximum torque line and the smoke-limiter. The end operating point, and how it is approached is, however, different. Then, the power transients are extended to driving missions, defined as, that a certain power has to be met as well as a certain energy has to be produced. This is done both with fixed output profiles and with the output power being a free variable. The time optimal control follows the fixed output profile even when the output power is free. These solutions are found to be almost fuel optimal despite being substantially faster than the minimum fuel solution with variable output power. The discussed control strategies are also seen to hold for sequences of power and energy steps.

scholarly journals IN-CYLINDER MASS FLOW ESTIMATION AND MANIFOLD PRESSURE DYNAMICS FOR STATE PREDICTION IN SI ENGINES

2014 ◽  
Vol 54 (3) ◽  
pp. 240-247 ◽  
Author(s):  
Wojnar Sławomir ◽  
Boris Rohal-Ilkiv ◽  
Peter Šimončic ◽  
Marek Honek ◽  
Csambál Jozef
Keyword(s):  
Control Strategies ◽  
Estimation Method ◽  
Mean Value ◽  
Intake Manifold ◽  
Flow Estimation ◽  
Engine Model ◽  
Pressure Dynamics ◽  
Estimation And Control ◽  
Cylinder Flow ◽  
And Control

The aim of this paper is to present a simple model of the intake manifold dynamics of a spark ignition (SI) engine and its possible application for estimation and control purposes. We focus on pressure dynamics, which may be regarded as the foundation for estimating future states and for designing model predictive control strategies suitable for maintaining the desired air fuel ratio (AFR). The flow rate measured at the inlet of the intake manifold and the in-cylinder flow estimation are considered as parts of the proposed model. In-cylinder flow estimation is crucial for engine control, where an accurate amount of aspired air forms the basis for computing the manipulated variables. The solutions presented here are based on the mean value engine model (MVEM) approach, using the speed-density method. The proposed in-cylinder flow estimation method is compared to measured values in an experimental setting, while one-step-ahead prediction is illustrated using simulation results.

Transient Control of Combustion Phasing and Lambda in a Six-Cylinder Port-Injected Natural-Gas Engine

2010 ◽  
Vol 132 (9) ◽  
Author(s):  
Mehrzad Kaiadi ◽  
Magnus Lewander ◽  
Patrick Borgqvist ◽  
Per Tunestal ◽  
Bengt Johansson
Keyword(s):  
Natural Gas ◽  
Control Strategies ◽  
Maximum Load ◽  
Spark Ignition Engines ◽  
Heavy Duty ◽  
Gas Engine ◽  
Natural Gas Engine ◽  
Engine Model ◽  
Transient Control ◽  
Cylinder Port

Fuel economy and emissions are the two central parameters in heavy duty engines. High exhaust gas recirculation rates combined with turbocharging has been identified as a promising way to increase the maximum load and efficiency of heavy duty spark ignition engines. With stoichiometric conditions, a three way catalyst can be used, which keeps the regulated emissions at very low levels. The Lambda window, which results in very low emissions, is very narrow. This issue is more complex with transient operation, resulting in losing brake efficiency and also catalyst converting efficiency. This paper presents different control strategies to maximize the reliability for maintaining efficiency and emissions levels under transient conditions. Different controllers are developed and tested successfully on a heavy duty six-cylinder port injected natural gas engine. Model predictive control was used to control lambda, which was modeled using system identification. Furthermore, a proportional integral regulator combined with a feedforward map for obtaining maximum brake torque timing was applied. The results show that excellent steady-state and transient performance can be achieved.

The Evolution Required in Standard Cars for the Use of New EGR-VGT Control Strategies

2005 ◽  
Author(s):  
J. F. Arnold ◽  
N. Langlois ◽  
H. Chafouk
Keyword(s):  
Diesel Engine ◽  
Control Strategies ◽  
Low Cost ◽  
Intake Manifold ◽  
Variable Geometry ◽  
Emission Norm ◽  
Variable Geometry Turbine ◽  
The Cost ◽  
Intake Manifold Pressure ◽  
New Strategies

This paper is a study into the possibility of using new control strategies in a standard car. The air system of a diesel engine equipped with a variable geometry turbine and an EGR system (EGR valve and throttle) is considered. New strategies, like GPC or H∞ permit an improvement of the control of both the fresh air flow and the intake manifold pressure. These strategies are not used today in standard car due to the mismatch of both the instrumentation of the ECU’s calculation power. The cost of proposed technology to meet the next emission norm are presented. Some low cost solutions are presented to permit an improvement of the engine control.

Modeling and Validation of a Lean Burn Natural Gas Engine

1998 ◽  
Vol 123 (3) ◽  
pp. 425-430 ◽  
Author(s):  
Anupam Gangopadhyay ◽  
Peter Meckl
Keyword(s):  
Natural Gas ◽  
Mean Value ◽  
Intake Manifold ◽  
State Variables ◽  
Lean Burn ◽  
Gas Engine ◽  
Gasoline Engines ◽  
Natural Gas Engine ◽  
Engine Model ◽  
Intake Manifold Pressure

In this paper, a control-oriented model of a medium-duty throttle-body natural gas engine is developed. The natural gas engine uses lean-burn technology without exhaust gas recirculation (EGR). The dynamic engine model differs from models of gasoline engines by including the natural gas fuel dynamics in the intake manifold. The model is based on a mean value concept and has three state variables: intake manifold pressure, fuel fraction in the intake manifold and the engine rotational speed. The resulting model has been validated in steady-state and transient operation over the usual operating range of the engine between 800 rpm and 2600 rpm with air/fuel ratios ranging between 18.0 and 24.0.

A Torque Balance Method for Multi-Cylinder Gasoline Engines With Non-Uniform Cylinder-to-Cylinder Combustion Strategies

2019 ◽  
Author(s):  
Qinghua Lin ◽  
Pingen Chen
Keyword(s):  
Catalytic Reduction ◽  
Control Strategies ◽  
Fuel Efficiency ◽  
The United States ◽  
Nox Emission ◽  
Successful Implementation ◽  
Lean Burn ◽  
Gasoline Engines ◽  
Engine Model ◽  
Lean Nox

Abstract Lean burn gasoline engines have attracted more and more attentions over the past two decades. One of the main challenges in commercializing lean burn gasoline engines in the United States is lean NOx control to meet the stringent NOx emission regulation. Several types of lean aftertreatment systems including passive selective catalytic reduction (SCR) systems and lean NOx traps (LNTs), have been intensively investigated to meet the NOx emission requirements without triggering significant penalties on fuel efficiency. One of the most promising technologies to achieve this goal is non-uniform cylinder-to-cylinder combustion (NUCCC) control strategies. However, successful implementation of NUCCC strategies are challenging tasks since it may cause cylinder-to-cylinder torque imbalance and thus deterioration of drivability. The purpose of this study is to propose and evaluate a systematic method for generating the references of fuel quantity and air quantity for different cylinders to simultaneously achieve cylinder-to-cylinder torque balance and non-uniform cylinder-to-cylinder air/fuel ratio (AFR) for multi-cylinder engines in various scenarios. To validate the effectiveness of the proposed method, simulation studies were carried out using a multi-zone engine model. The simulation results show that, the proposed references, if successfully tracked, can lead to torque balance across the cylinders as well as non-uniform cylinder-to-cylinder AFR.

Steady-state and transient control strategies for a two-stage turbocharged diesel engine

2017 ◽  
Vol 232 (9) ◽  
pp. 1167-1179 ◽  
Author(s):  
Zhilong Hu ◽  
Kangyao Deng ◽  
Yi Cui ◽  
Xinxin Yang ◽  
Baochuan Zhang
Keyword(s):  
Steady State ◽  
Transient Response ◽  
Closed Loop ◽  
Control Strategies ◽  
Open Loop ◽  
Two Stage ◽  
Loop Control ◽  
Turbocharging System ◽  
Transient Control ◽  
Response Performance

Two-stage turbocharging technology is widely used to achieve higher engine power density and lower exhaust emissions. To solve a series of contradictions in matching, a regulated two-stage (RTS) turbocharging system is applied to reasonably control boost pressure. This paper investigated steady-state and transient control strategies for an RTS turbocharging system to achieve optimum fuel economy in steady-state conditions and better performance in transient conditions. The economic control strategies for steady-state operational conditions were based on an economic regulation law, which was established by a steady-state test of an engine with an RTS turbocharging system under all operating conditions. To optimize the transient performance, open-loop and closed-loop control systems (the latter with dynamic judgement) for the RTS system were designed and validated with experiments on a heavy-duty diesel engine. The experimental results demonstrated that the open-loop control strategy and the closed-loop strategy with dynamic judgement could improve the transient response performance. The optimum transient response performance was achieved by the closed-loop control system with dynamic judgement. Additionally, the combination of steady-state and transient control strategies could achieve the best fuel economy in steady-state conditions and good transient response performances.

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