Transient Air-to-Fuel Ratio Control of an Spark Ignited Engine Using Linear Quadratic Tracking

2013 ◽  
Vol 136 (2) ◽  
Author(s):  
Stephen Pace ◽  
Guoming G. Zhu
Keyword(s):  
Internal Combustion Engines ◽  
Inverse Dynamics ◽  
Fuel Injection ◽  
Time Interval ◽  
Linear Quadratic ◽  
Fuel Ratio ◽  
Tracking Controller ◽  
Wall Wetting ◽  
Quadratic Tracking ◽  
Wetting Dynamics

Modern spark ignited (SI) internal combustion engines maintain their air-to-fuel ratio (AFR) at a desired level to maximize the three-way catalyst conversion efficiency and durability. However, maintaining the engine AFR during its transient operation is quite challenging due to rapid changes of driver demand or engine throttle. Conventional transient AFR control is based upon the inverse dynamics of the engine fueling dynamics and the measured mass air flow (MAF) rate to obtain the desired AFR of the gas mixture trapped in the cylinder. This paper develops a linear quadratic (LQ) tracking controller to regulate the transient AFR based upon a control-oriented model of the engine port fuel injection (PFI) wall wetting dynamics and the air intake dynamics from the measured airflow to the manifold pressure. The LQ tracking controller is designed to optimally track the desired AFR by minimizing the error between the trapped in-cylinder air mass and the product of the desired AFR and fuel mass over a given time interval. The performance of the optimal LQ tracking controller was compared with the conventional transient fueling control based on the inverse fueling dynamics through simulations and showed improvement over the baseline conventional inverse fueling dynamics controller. To validate the control strategy on an actual engine, a 0.4 l single cylinder direct-injection (DI) engine was used. The PFI wall wetting dynamics were simulated in the engine controller after the DI injector control signal. Engine load transition tests for the simulated PFI case were conducted on an engine dynamometer, and the results showed improvement over the baseline transient fueling controller based on the inverse fueling dynamics.

Optimal LQ Transient Air-to-Fuel Ratio Control of an Internal Combustion Engine

2011 ◽  
Author(s):  
Stephen Pace ◽  
Guoming G. Zhu
Keyword(s):  
Internal Combustion Engines ◽  
Inverse Dynamics ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Time Interval ◽  
Fuel Injector ◽  
Linear Quadratic ◽  
Fuel Ratio ◽  
Tracking Controller ◽  
Wetting Dynamics

Most modern spark ignited (SI) internal combustion engines maintain their air-to-fuel ratio (AFR) at a desired level to maximize the three-way catalyst conversion efficiency and to extend its life. However, maintaining the engine AFR during its transient operation is quite challenging due to rapid changes of driver demands. Conventional transient AFR control is based upon the inverse dynamics of the engine port-fuel-injection well-wetting dynamics and the measured mass air flow rate. This paper develops a dynamic linear quadratic (LQ) tracking controller to regulate the AFR using a control oriented model of the wall wetting dynamics of a port fuel injector (PFI) and estimated transport delays of the airflow travel and throttle dynamics. The LQ tracking controller is designed to optimally track the measured airflow through the throttle during engine transients over a given time interval. The performance of the optimal LQ tracking controller was compared with the conventional inverse fueling dynamics through simulations and showed improvement over the baseline controller.

Adaptive and predictive control of fuel injection with time delay consideration for air–fuel ratio regulation of gasoline direct injection engines

2016 ◽  
Vol 231 (8) ◽  
pp. 1022-1033
Author(s):  
Yu Feng ◽  
Xiaohong Jiao ◽  
Zhijing Wang
Keyword(s):  
Time Delay ◽  
Parameter Uncertainty ◽  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Direct Injection ◽  
Measurement Noise ◽  
Gasoline Direct Injection ◽  
Accurate Estimation ◽  
Fuel Ratio ◽  
Modelling Error

Accurate air–fuel ratio control is a key affecting factor for improving fuel economy and reducing exhaust emissions for internal combustion engines. Challenging issues in air–fuel control are the accurate estimation of cylinder air charge for achieving the stoichiometric in-cylinder air–fuel ratio and the disposition of measurement time delay from the oxygen sensor for removing its limits on the achievable feedback performance. In this article, based on hybrid discrete–continuous-time descriptions for the cylinder air charge dynamics and air–fuel feedback regulation controlled plant, a novel fuel injection controller with adaptive feedback and predictive feedforward is designed to ensure accurate air–fuel control of a gasoline direct injection engine. The feedforward fuel injection is determined based on the cylinder air charge prediction using unscented Kalman filter for the compensation of the injection delay and modelling error and the attenuation of the measurement noise. The feedback fuel compensation is designed as a proportional-integral structure with adaptive gains by means of an adaptive stabilization method of uncertain input delayed systems for the management of the transport delay and parameter uncertainty. The effectiveness of the proposed fuelling control against time delay, modelling error, measurement noise and parameter uncertainty is demonstrated by the simulation utilizing experimental data from a real V6 GDI engine.

Discrete Time Linear Quadratic Tracking Controller for Omni-Directional Mobile Robots

2011 ◽  
Author(s):  
Ehsan Hashemi ◽  
Maani Ghaffari Jadidi
Keyword(s):  
Control System ◽  
Path Planning ◽  
Mobile Robots ◽  
Controller Design ◽  
Optimal Solution ◽  
Linear Quadratic Regulator ◽  
Reference Trajectory ◽  
Linear Quadratic ◽  
Tracking Controller ◽  
Quadratic Tracking

The purpose of this investigation is to suggest and examine a trajectory follower control system for linear discrete dynamic model of omni-directional mobile robots to reach a controller with optimal inputs for drivers. Introducing optimal controllers for multi input-multi output control systems in acceleration and deceleration maneuvers to track a specified path is one of essential subjects for motion study of omni-directional mobile robots. Regulated drivers’ rotational velocities and torques greatly affect the ability of these robots to perform trajectory planner tasks. Moreover, environmental influencing factors shall also be considered in such robot models for accurate path planning. Presented tracking control system in this article provides an optimal solution to minimize differences between reference trajectory and system output in the lately developed simulated model. Trajectory following system together with implemented kinematic and dynamic modeling for an optimal controller to satisfy the path planning prerequisites is mainly discussed in this paper in several sections. Main topics presented and discussed in this article are considerable improvements in simulation of the newly optimized controller by Linear Quadratic Regulator and Tracking. Utilizing the new approach on tracking controller design results in the more precise and appropriate tracking behavior of omni-directional mobile robots as the simulation and experimental results confirm this issue.

Measurement of cycle-resolved engine-out soot concentration from a diesel-pilot assisted natural gas direct-injection compression-ignition engine

2021 ◽  
pp. 146808742098626
Author(s):  
Pooyan Kheirkhah ◽  
Patrick Kirchen ◽  
Steven Rogak
Keyword(s):  
Response Time ◽  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Exhaust System ◽  
Cycle Period ◽  
Scanning Mobility Particle Sizer ◽  
Compression Ignition Engine ◽  
Engine Operation ◽  
Exhaust Port ◽  
Exhaust Stream

Exhaust-stream particulate matter (PM) emission from combustion sources such as internal combustion engines are typically characterized with modest temporal resolutions; however, in-cylinder investigations have demonstrated significant variability and the importance of individual cycles in transient PM emissions. Here, using a Fast Exhaust Nephelometer (FEN), a methodology is developed for measuring the cycle-specific PM concentration at the exhaust port of a single-cylinder research engine. The measured FEN light-scattering is converted to cycle-resolved soot mass concentration ([Formula: see text]), and used to characterize the variability of engine-out soot emission. To validate this method, exhaust-port FEN measurements are compared with diluted gravimetric PM mass and scanning mobility particle sizer (SMPS) measurements, resulting in close agreements with an overall root-mean-square deviation of better than 30%. It is noted that when PM is sampled downstream in the exhaust system, the particles are larger by 50–70 nm due to coagulation. The response time of the FEN was characterized using a “skip-firing” scheme, by enabling and disabling the fuel injection during otherwise steady-state operation. The average response time due to sample transfer and mixing times is 55 ms, well below the engine cycle period (100 ms) for the considered engine speeds, thus suitable for single-cycle measurements carried out in this work. Utilizing the fast-response capability of the FEN, it is observed that cycle-specific gross indicated mean effective pressure (GIMEP) and [Formula: see text] are negatively correlated ([Formula: see text]: 0.2–0.7), implying that cycles with lower GIMEP emit more soot. The physical causes of this association deserve further investigation, but are expected to be caused by local fuel-air mixing effects. The averaged exhaust-port [Formula: see text] is similar to the diluted gravimetric measurements, but the cycle-to-cycle variations can only be detected with the FEN. The methodology developed here will be used in future investigations to characterize PM emissions during transient engine operation, and to enable exhaust-stream PM measurements for optical engine experiments.

scholarly journals Two Inverse Problems Solution by Feedback Tracking Control

Axioms ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 137
Author(s):  
Vladimir Turetsky
Keyword(s):  
Optimal Control ◽  
Optimal Control Problem ◽  
Control Problem ◽  
Feedback Linearization ◽  
Linear Quadratic ◽  
Linear Quadratic Optimal Control ◽  
Linear Quadratic Tracking ◽  
Ill Posed ◽  
Quadratic Optimal Control ◽  
Quadratic Tracking

Two inverse ill-posed problems are considered. The first problem is an input restoration of a linear system. The second one is a restoration of time-dependent coefficients of a linear ordinary differential equation. Both problems are reformulated as auxiliary optimal control problems with regularizing cost functional. For the coefficients restoration problem, two control models are proposed. In the first model, the control coefficients are approximated by the output and the estimates of its derivatives. This model yields an approximating linear-quadratic optimal control problem having a known explicit solution. The derivatives are also obtained as auxiliary linear-quadratic tracking controls. The second control model is accurate and leads to a bilinear-quadratic optimal control problem. The latter is tackled in two ways: by an iterative procedure and by a feedback linearization. Simulation results show that a bilinear model provides more accurate coefficients estimates.

scholarly journals Adaptive Air-Fuel Ratio Regulation for Port-Injected Spark-Ignited Engines Based on a Generalized Predictive Control Method

Energies ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 173 ◽  
Author(s):  
Lei Meng ◽  
Xiaofeng Wang ◽  
Chunnian Zeng ◽  
Jie Luo
Keyword(s):  
Predictive Control ◽  
Noise Suppression ◽  
Control Method ◽  
Simulation Analysis ◽  
Catalytic Converter ◽  
Exhaust Emission ◽  
Generalized Predictive Control ◽  
Si Engine ◽  
Fuel Ratio ◽  
Wall Wetting

The accurate air-fuel ratio (AFR) control is crucial for the exhaust emission reduction based on the three-way catalytic converter in the spark ignition (SI) engine. The difficulties in transient cylinder air mass flow measurement, the existing fuel mass wall-wetting phenomenon, and the unfixed AFR path dynamic variations make the design of the AFR controller a challenging task. In this paper, an adaptive AFR regulation controller is designed using the feedforward and feedback control scheme based on the dynamical modelling of the AFR path. The generalized predictive control method is proposed to solve the problems of inherent nonlinearities, time delays, parameter variations, and uncertainties in the AFR closed loop. The simulation analysis is investigated for the effectiveness of noise suppression, online prediction, and self-correction on the SI engine system. Moreover, the experimental verification shows an acceptable performance of the designed controller and the potential usage of the generalized predictive control in AFR regulation application.

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