Closure to “Discussion of ‘Closed Loop, Knock Adaptive Spark Timing Control Based on Cylinder Pressure’” (1979, ASME J. Dyn. Syst., Meas., Control, 101, pp. 69–70)

1979 ◽  
Vol 101 (1) ◽  
pp. 70-70
Author(s):  
R. J. Hosey ◽  
J. D. Powell
Keyword(s):  
Closed Loop ◽  
Cylinder Pressure ◽  
Timing Control ◽  
Spark Timing

Spark Ignition Feedback Control by Means of Combustion Phase Indicators on Steady and Transient Operation

2014 ◽  
Vol 136 (5) ◽  
Author(s):  
Pipitone Emiliano
Keyword(s):  
Feedback Control ◽  
Closed Loop ◽  
Spark Ignition ◽  
Engine Control ◽  
Cylinder Pressure ◽  
Timing Control ◽  
Spark Timing ◽  
Combustion Phase ◽  
Si Engines ◽  
And Control

In order to reduce fuel cost and CO2 emissions, modern spark ignition (SI) engines need to lower as much as possible fuel consumption. A crucial factor for efficiency improvement is represented by the combustion phase, which in an SI engine is controlled acting on the spark advance. This fundamental engine parameter is currently controlled in an open-loop by means of maps stored in the electronic control unit (ECU) memory: such kind of control, however, does not allow running the engine always at its best performance, since optimal combustion phase depends on many variables, like ambient conditions, fuel quality, engine aging, and wear, etc. A better choice would be represented by a closed-loop spark timing control, which may be pursued by means of combustion phase indicators, i.e., parameters mostly derived from in-cylinder pressure analysis that assume fixed reference values when the combustion phase is optimal. As documented in literature (Pestana, 1989, “Engine Control Methods Using Combustion Pressure Feedback,” SAE Paper No. 890758; BERU Pressure Sensor Glow Plug (PSG) for Diesel Engines, http://beru.federalmogul.com; Sensata CPOS SERIES—Cylinder Pressure Only Sensors, http://www.sensata.com/download/cpos.pdf; Malaczynski et al., 2013, “Ion-Sense-Based Real-Time Combustion Sensing for Closed-Loop Engine Control,” SAE Int. J. Eng., 6(1), pp. 267–277; Yoshihisa et al., 1988, “MBT Control Through Individual Cylinder Pressure Detection,” SAE Paper 881779; Powell, 1993, “Engine Control Using Cylinder Pressure: Past, Present, and Future,” J. Dyn. Syst., Meas. Control, 115, pp. 343–350; Muller et al., 2000, “Combustion Pressure Based Engine Management System,” SAE Paper 2000-01-0928; Yoon et al., 2000, “Closed-Loop Control of Spark Advance and Air-Fuel Ratio in SI Engines Using Cylinder Pressure,” SAE Paper 2000-01-0933; Eriksson, 1999, “Spark Advance Modeling and Control,” Dissertation N° 580, Linkoping Studies in Science and Technology, Linköping, Sweden; Samir et al., 2011, “Neural Networks and Fuzzy Logic-Based Spark Advance Control of SI Engines,” Expert Syst. Appl., 38, pp. 6916–6925; Cook et al., 1947, “Spark-Timing Control Based on Correlation of Maximum-Economy Spark Timing, Flame-Front Travel, and Cylinder Pressure Rise,” NACA Technical Note 1217; Bargende, 1995, “Most Optimal Location of 50% Mass Fraction Burned and Automatic Knock Detection,” MTZ, 10(56), pp. 632–638.), the use of combustion phase indicators allows the determination of the best spark advance, apart from any variable or boundary condition. The implementation of a feedback spark timing control, based on the use of these combustion phase indicators, would ensure the minimum fuel consumption in every possible condition. Despite the presence of many literature references on the use combustion phase indicators, there is no evidence of any experimental comparison on the performance obtainable, in terms of both control accuracy and transient response, by the use of such indicators in a spark timing feedback control. The author, hence, carried out a proper experimental campaign comparing the performances of a proportional-integral spark timing control based on the use of five different in-cylinder pressure derived indicators. The experiments were carried out on a bench test, equipped with a series production four cylinder spark ignition engine and an eddy current dynamometer, using two data acquisition (DAQ) systems for data acquisition and spark timing control. Pressure sampling was performed by means of a flush mounted piezoelectric pressure transducer with the resolution of one crank angle degree. The feedback control was compared to the conventional map based control in terms of response time, control stability, and control accuracy in three different kinds of tests: steady-state, step response, and transient operation. All the combustion phase indicators proved to be suitable for proportional-integral feedback spark advance control, allowing fast and reliable control even in transient operations.

Closed Loop, Knock Adaptive Spark Timing Control Based on Cylinder Pressure

1979 ◽  
Vol 101 (1) ◽  
pp. 64-69 ◽  
Author(s):  
R. J. Hosey ◽  
J. D. Powell
Keyword(s):  
Engine Speed ◽  
Closed Loop ◽  
Fuel Efficiency ◽  
Combustion Process ◽  
Spark Ignition Engine ◽  
Cylinder Pressure ◽  
Timing Control ◽  
Spark Timing ◽  
Engine Knock ◽  
Reduction Of Emissions

One of the important inputs to a spark ignition engine which affects nearly all engine outputs is spark advance. Spark advance not only affects fuel efficiency and exhaust emissions but is also a factor in the tendency for detonation or engine knock. Increasing pressure for reduction of emissions and better fuel economy is making effective spark advance control more important. The desire for improved efficiency is complicated by the increased use of low octane, lead-free gasoline which is an influence toward conservative, inefficient engine designs for reduction of engine knock. Conventional spark advance systems control on parameters which are inputs to the combustion process, such as manifold vacuum and engine speed. This paper describes a microprocessor based spark timing controller based on measurements of cylinder pressure history, a parameter which is a result of the combustion process. To feedback element is an experimental piezoelectric pressure transducer of an inexpensive design which would be suitable for mass production. Results are presented showing that this feedback controller is able to control spark advance to 1 percent of optimum even over fuel-air ratio changes of 40 percent. The controller also effectively controls engine knock to levels which are not harmful.

An experimental study on optimal spark timing control for improved performance of a flex fuel vehicle engine

2019 ◽  
Vol 234 (5) ◽  
pp. 1294-1303
Author(s):  
Junsang Yoo ◽  
Taeyong Lee ◽  
Pyungsik Go ◽  
Yongseok Cho ◽  
Kwangsoon Choi ◽  
...  
Keyword(s):  
Empirical Equation ◽  
Interpolation Method ◽  
Linear Interpolation ◽  
Combustion Characteristics ◽  
Combustion Stability ◽  
Timing Control ◽  
Vehicle Engine ◽  
Spark Timing ◽  
Linear Interpolation Method ◽  
Blended Fuels

In the American continent, the most frequently used alternative fuel is ethanol. Especially in Brazil, various blends of gasoline–ethanol fuels are widely spread. The vehicle using blended fuel is called flexible fuel vehicle. Because of several selections for the blending ratios in gas stations, the fuel properties may vary after refueling depending on a driver’s selection. Also, the combustion characteristics of the flexible fuel vehicle engine may change. In order to respond to the flexible fuel vehicle market in Brazil, a study on blended fuels is performed. The main purpose of this study is to enhance performance of the flexible fuel vehicle engine to target Brazilian market. Therefore, we investigated combustion characteristics and optimal spark timings of the blended fuels with various blending ratios to improve the performance of the flexible fuel vehicle engine. As a tool for prediction of the optimal spark timing for the 1.6L flexible fuel vehicle engine, the empirical equation was suggested. The validity of the equation was investigated by comparing the predicted optimal spark timings with the stock spark timings through engine tests. When the stock spark timings of E0 and E100 were optimal, the empirical equation predicted the actual optimal spark timings for blended fuels with a good accuracy. In all conditions, by optimizing spark timing control, performance was improved. Especially, torque improvements of E30 and E50 fuels were 5.4% and 1.8%, respectively, without affecting combustion stability. From these results, it was concluded that the linear interpolation method is not suitable for flexible fuel vehicle engine control. Instead of linear interpolation method, optimal spark timing which reflects specific octane numbers of gasoline–ethanol blended fuels should be applied to maximize performance of the flexible fuel vehicle engine. The results of this study are expected to save the effort required for engine calibration when developing new flexible fuel vehicle engines and to be used as a basic strategy to improve the performance of other flexible fuel vehicle engines.

Master cylinder pressure reduction logic for cooperative work between electro-hydraulic brake system and anti-lock braking system based on speed servo system

2020 ◽  
Vol 234 (13) ◽  
pp. 3042-3055
Author(s):  
Lu Xiong ◽  
Wei Han ◽  
Zhuoping Yu ◽  
Jian Lin ◽  
Songyun Xu
Keyword(s):  
Feedback Control ◽  
Closed Loop ◽  
Servo System ◽  
Brake System ◽  
Extreme Condition ◽  
Pressure Reduction ◽  
Cylinder Pressure ◽  
Master Cylinder ◽  
Braking System ◽  
Hydraulic Brake

As one feasible solution of brake-by-wire systems, electro-hydraulic brake system has been made available into production recently. Electro-hydraulic brake system must work cooperatively with the hydraulic control unit of anti-lock braking system. Due to the mechanical configuration involving electric motor + reduction gear, the electro-hydraulic brake system could be stiffer in contrast to a conventional vacuum booster. That is to say, higher pressure peaks and pressure oscillation could occur during an active anti-lock braking system control. Actually, however, electro-hydraulic brake system and anti-lock braking system are produced by different suppliers considering brake systems already in production. Limited signals and operations of anti-lock braking system could be provided to the supplier of electro-hydraulic brake system. In this work, a master cylinder pressure reduction logic is designed based on speed servo system for active pressure modulation of electro-hydraulic brake system under the anti-lock braking system–triggered situation. The pressure reduction logic comprises of model-based friction compensation, feedforward and double closed-loop feedback control. The pressure closed-loop is designed as the outer loop, and the motor rotation speed closed-loop is drawn into the inner loop of feedback control. The effectiveness of the proposed controller is validated by vehicle experiment in typical braking situations. The results show that the controller remains stable against parameter uncertainties in extreme condition such as low temperature and mismatch of friction model. In contrast to the previous methods, the comparison results display the improved dynamic cooperative performance of electro-hydraulic brake system and anti-lock braking system and robustness.

scholarly journals Closed-loop control of a dual-fuel engine working with different combustion modes using in-cylinder pressure feedback

2019 ◽  
Vol 21 (3) ◽  
pp. 484-496 ◽  
Author(s):  
Carlos Guardiola ◽  
Benjamín Pla ◽  
Pau Bares ◽  
Alvin Barbier
Keyword(s):  
Closed Loop ◽  
Combustion Engine ◽  
Fuel Combustion ◽  
Operating Conditions ◽  
Dual Fuel ◽  
Maximum Pressure ◽  
Cylinder Pressure ◽  
Pressure Derivative ◽  
Combustion Modes ◽  
Dual Fuel Combustion

This work presents a closed-loop combustion control concept using in-cylinder pressure as a feedback in a dual-fuel combustion engine. At low load, reactivity controlled compression ignition combustion was used while a diffusive dual-fuel combustion was performed at higher loads. The aim of the presented controller is to maintain the indicated mean effective pressure and the combustion phasing at a target value, and to keep the maximum pressure derivative under a limit to avoid engine damage in all the combustion modes by cyclically adapting the injection settings. Various tests were performed at steady-state conditions showing good abilities to fulfil the expected operating conditions but also to reject disturbances such as intake pressure or exhaust gas recirculation variations. Finally, the proposed control strategy was tested during a load transient resulting in a combustion switching-mode and the results exhibited the closed-loop potential for controlling such combustion concept.

Effects of Different LPG Fuel Systems on Performances of Variable Compression Ratio Single Cylinder Engine

2002 ◽  
Author(s):  
G. H. Choi ◽  
J. H. Kim ◽  
Christian Homeyer
Keyword(s):  
Liquid Phase ◽  
Heat Release ◽  
Compression Ratio ◽  
Power Output ◽  
Alternative Fuels ◽  
Gasoline Engine ◽  
Cylinder Pressure ◽  
Maximum Heat ◽  
Spark Timing ◽  
Test Engine

Since the early 20th century, most ground vehicles are driven with gasoline and diesel. The degradation of the environment affects human on earth unless the quality of the air is improved. One of the alternative fuels, LPG, is potentially capable of lowering vehicular emissions when compared to gasoline or diesel. There is a penalty in power output resulting from the use of LPG because the engine can induce less amount of air with Mixer system comparing with gasoline engine. Currently, the liquid-phase LPG is injected into the intake port of the engine, the fuel vaporizes enroute to the combustion chamber. Therefore, the performance and combustion processes of the tested engine are investigated with different LPG fuel systems. The test engine was developed and named heavy-duty VACRE. The test engine for this work operates 1400rpm with MBT conditions. The major conclusions of the work include; 1) The power output of LPi system with liquid-phase is approximately 17% higher than that of vapor-phase Mixer system due to increases of volumetric efficiency. And the MBT spark timing of LPi system is approximately 25% more advanced than that of Mixer system at λ value 1.0; 2) The LPi system shows both the maximum heat release rate and the cumulative heat release to be approximately 20% higher than the Mixer system; 3) Maximum cylinder pressure decrease with increase of compression ratio and a point of maximum cylinder pressure is delayed with high compression ratio.

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