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.

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.

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.

Exoskeleton design and adaptive compliance control for hand rehabilitation

2019 ◽  
Vol 42 (3) ◽  
pp. 493-502 ◽  
Author(s):  
Gazi Akgun ◽  
Ahmet Emre Cetin ◽  
Erkan Kaplanoglu
Keyword(s):  
Control Strategies ◽  
Estimation Method ◽  
Force Sensor ◽  
Hand Rehabilitation ◽  
Mechanical Structure ◽  
Luenberger Observer ◽  
On Line ◽  
Active Rehabilitation ◽  
And Control ◽  
Rehabilitation Tasks

An adaptive robotic system has been developed to be used for hand rehabilitation. Previously developed exoskeletons are either very complex in terms of mechanism, hardware and software, or simple but have limited functionality only for a specific rehabilitation task. Some of these studies use simple position controllers considering only to improve the trajectory tracking performance of the exoskeleton which is inadequate in terms of safety and health of the patient. Some of them focus only on either passive or active rehabilitation, but not both together. Some others use EMG signals to assist the patient, but this time active rehabilitation is impossible unless different designs and control strategies are not developed. The proposed mechanical structure is extremely simple. The middle and the proximal phalanxes are used as a link of consecutively connected two 4-bar mechanisms, respectively. The PIP and MCP joints are actuated by a single electro mechanical cylinder to produce complex flexion and extension movements. It is simpler than similar ones from aspect with the mechanical structure and the biodynamic fit of the hand, making it practicable in terms of production and personal usage. Simple design lets to implement adaptive compliance controller for all active and passive rehabilitation tasks, instead of developing complex and different strategies for different rehabilitation tasks. Furthermore, using the Luenberger observer for unmeasured velocity state variable, an on-line estimation method is used to estimate the dynamic parameters of the system. This makes possible to estimate the force exerted by the patient as well, without a force sensor.

A Rapid Engine Prototyping Methodology: Linking Geometry, Flow Field, Combustion, Performance and Control

2001 ◽  
Author(s):  
Jang-Hyok Ko ◽  
Yann G. Guezennec ◽  
Amr Radwan ◽  
Giorgio Rizzoni ◽  
Woong-Chul Choi
Keyword(s):  
System Development ◽  
Control Strategies ◽  
Mean Value ◽  
Combustion Characteristics ◽  
Engine Simulation ◽  
Engine Design ◽  
Crank Angle ◽  
Simulation Results ◽  
Cylinder Flows ◽  
And Control

Abstract In this paper, we present an overview of a rapid engine prototyping methodology which can be an extremely valuable tool from preliminary engine design optimization to control system development. The methodology comprises several steps which can be used separately or in conjunction. Specifically, the approach consists of: i) linking engine geometry and valve events to in-cylinder flows; ii) linking in-cylinder flows to combustion characteristics; iii) linking combustion characteristics to crank-angle resolved engine simulation results; and iv) linking crank angle-resolved engine simulation results to a mean value dynamic engine/powertrain simulator to develop and optimize control strategies. One of the chief advantages of the proposed methodology is the ability of performing these tasks prior to having an engine prototype built and running on a dynamometer.

Sign in / Sign up

Export Citation Format

Share Document