Optimization of Engine Control Strategies for Low Fuel Consumption in Heavy-Duty Commercial Vehicles

The reduction of fuel consumption in engines is always considered of vital importance.Along these lines,in this work,this goal was attained by optimizing the heavy-duty commercial vehicle engine control strategy.More specifically,at first,a general first principles model for heavy-duty commercial vehicles and a transient fuel consumptionmodel for heavy-duty commercial vehicles were developed and the parameters were adjusted to fit the empirical data.The accuracy of the proposed modelwas demonstrated fromthe stage and the final results.Next,the control optimization problem resulting in low fuel consumption in heavy commercial vehicles was described,with minimal fuel usage as the optimization goal and throttle opening as the control variable.Then,a time-continuous engine management approach was assessed.Next,the factors that influence low fuel consumption in heavy-duty commercial vehicles were systematically examined.To reduce the computing complexity,the control strategies related to the time constraints of the engine were parametrized using three different methods.The most effective solution was obtained by applying a global optimization strategy because the constrained optimization problem was nonlinear.Finally,the effectiveness of the low-fuel consumption engine control strategy was demonstrated by comparing the simulated and field test results.

Comparison of generalized engine control and MPC based on maximum principle

Automotive engine control has been continuously improved due to the strong demands from the society and the market since introducing electronic controls but not always following control theories. Therefore, it is not easy for researchers from academia and even engineers from the automotive industry to grasp the whole aspect of engine control. To encounter the issue, important features of engine control are extracted and generalized from the standpoint of control engineering. Comparisons of the control and model predictive control （MPC） showed an outstanding performance of the control generalized from engine controls and how to apply MPC in the framework.

Time-triggered State-machine Reliable Software Architecture for Micro Turbine Engine Control

Time-triggered （TT） embedded software pattern is well accepted in aerospace industry for its high reliability. Fi-nite-state-machine （FSM） design method is widely used for its high efficiency and predictable behavior. In this paper, the time-triggered and state-machine combination software architecture is implemented for a 25 kg thrust micro turbine engine （MTE） used for unmanned aerial vehicle （UAV） system; also model-based-design development workflow for airworthiness software directive DO-178B is utilized. Experimental results show that time-triggered state-machine software architecture and development method could shorten the system development time, reduce the system test cost and make the turbine engine easily comply with the airworthiness rules.

APPLICATION OF CIRCUIT SIMULATION IN HARDWARE DESIGN FOR ELECTRONIC CONTROL HIGH PRESSURE COMMON-RAIL FUEL SYSTEM OF DIESEL ENGINE

By means of circuit simulation, hardware of electronic control unit （ECU） of high pressure common-rail electronic control fuel system for diesel engine is designed. According to the system requirements for hardware of ECU, signal-processing circuit of variable reluctance （VR） sensor, filter circuit for input signal, high voltage power circuit and driver and protection circuit of solenoid are simulated as emphases. Difficulties of wide scope of VR sensor output signal, efficiency of high voltage power and reliable and swift driver of solenoid are solved. The results of simulation show that the hardware meets the requirement of the fuel system. At the same time, circuit simulation can greatly increase quality of the design, alleviate design labor and shorten design time.

Novel Oxygen Storage Components Promoted Palladium Catalysts for Emission Control in Natural Gas Powered Engines

A three-way catalyst comprised novel oxygen storage components for emission control in natural gas powered engines was prepared. The addition of novel oxygen storage components to the Pd/γ-Al2O3 catalysts resulted in improved activities of the fresh and aged catalyst by lowering the light-off temperature for methane in natural gas engines exhaust.

Evaluation of Environmental Sound Pressure Level,Drawing of Noise-Isosonic Map Using Surfer V.19,and Prioritization of Engineering Noise Control Methods Using the Analytic Hierarchy Process(AHP):A Field Study in CGS Stations

Noise pollution is one of the most significant harmful physical factors in the industrial and occupational environments.Due to the high costs of exposure to excessive noise;continuous sound evaluation,propose and implement noise control plans in occupational environments is necessary.Thus,the present study aimed to review environmental sound measurements,drawing of noise maps,and prioritizing the engineering noise control methods using the Analytic Hierarchy Process(AHP).This study was a descriptive-analytical study that aimed to assess occupational noises and present a control plan in the City Gas Stations(CGSs)of Kerman,Iran in 2021.The present study was done in two phases.In the first phase,six CGSs were investigated to measure and evaluate the noise.In addition,the noise map of a CGS was drawn using the Surfer software.Finally,the AHP was used in the second phase of the research to prioritize the control measures.In this phase,four criteria and ten alternatives were identified.According to first phase results,the sound pressure level(SPL)of the stations varied from 76 to 98 dBA.Besides,the majority of the studied stations had a sound level higher than 85 dBA(danger zone).The second phase of the study showed that out of the four evaluated criteria,the executability criterion had the highest impact and the cost criterion had the lowest impact on the selection of control measures with a weight of 0.587 and 0.052,respectively.Based on the results of prioritization of the alternatives,using a silenced regulator(weight of 0.223)and increasing the thickness of the tube(weight of 0.023)had the highest and lowest priorities among the alternatives,respectively.The use of engineering noise control methods such as using silenced regulators was the best way to control the noises of CGSs.Additionally;it is noteworthy that AHP is a practical method for prioritizing alternatives to achieve the most accurate decision-making.The results of AHP can be of great help to health and safety experts and managers in choosing the sound engineering control measures more precisely.

Control Engineering of China Special Issue on "Control Systems Engineering"

Control systems contribute to every aspect of modem society.In our life control systems exist in almost everywhere such as toasters,VCRs and smart phones.In science and technology,control systems already have widespread applications,for example,steering ships,guiding missiles and driving driverless cars in the near future.In all the control systems,systems are the key platform where control should be put into.It is at the system level that control shows its values.Extracting and formulating

Raman Scattering Modification in Monolayer ReS_2 Controlled by Strain Engineering

Regulation of optical properties and electronic structure of two-dimensionM layered ReS2 materials has attracted much attention due to their potential in electronic devices. However, the identification of structure transformation of monolayer ReS2 induced by strain is greatly lacking. In this work, the Raman spectra of monolayer ReS2 with external strain are determined theoretically based on the density function theory. Due to the lower structural symmetry, deformation induced by external strain can only regulate the Raman mode intensity but cannot lead to Raman mode shifts. Our calculations suggest that structural deformation induced by external strain can be identified by Raman scattering.

CONTROL ENGINEERING China 2007年度最佳产品奖投票开始

金秋10月,CONTROL ENGINEERING China 2007年度最佳产品奖活动也已进入最关键的阶段,那就是由我们杂志读者及网站(www.cechinamag.com)注册用户,最终投票决定出分属于8个产品目录的24款最佳产品奖与8款本土最佳创新产品奖。

Simulation of VGT control based on charge oxygen concentration

A turbocharged diesel engine model was built with the GT-Power software,and experimentally verified.Then two different control variables for the control of the variable geometry turbocharger（VGT）were described,and their distinct effects on engine performance,i.e.NOxand soot emissions and fuel consumption,were simulated and compared on the basis of this model.The results showed that NOxemissions decreased obviously with the increase of exhaust gas recirculation（EGR）rate at constant boost pressure condition,but soot emissions and fuel consumption considerably increased.It was a good way to reduce NOxemissions without increasing fuel consumption and soot emissions when VGT was controlled to maintain the excess oxygen ratio unchanged as EGR rate increases.

Fuzzy controller design for networked control system with time-variant delays

Networked control system is new hot-point in control engineering. A new delayed model for networked control systems is presented, based on which an LQR controller is designed. A method of delays estimation online is also given. For the difficulty on implementation of LQR in NCSs with time-variant delays, the Mamdani intelligent logic with LQR controller is addressed. The stability of the networked control system is also given. Simulation results prove that the novel controller can make the system stable and robustly preserve the performance in terms of time-variant delays.

Control Algorithm of Electric Vehicle in Coasting Mode Based on Driving Feeling

Coasting in gear is a common driving mode for the conventional vehicle equipped with the internal combustion engine（ICE）, and the assistant braking function of ICE is utilized to decelerate the vehicle in this mode. However, the electric vehicle（EV） does not have this feature in the coasting mode due to the relatively small inertia of the driving motor, so it will cause the driver cannot obtain the similar driving feeling to that of the conventional vehicle, and even a traffic accident may occur if the driver cannot immediately adapt to the changes. In this paper, the coasting control for EV is researched based on the driving feeling. A conventional vehicle equipped with continuously variable transmission（CVT） is taken as the reference vehicle, and the combined simulation model of EV is established based on AVL CRUISE and MATLAB/Simulink. The torque characteristic of the CVT output shaft is measured in coasting mode, and the data are smoothed and fitted to a polynomial curve. For the EV in coasting mode, if the state of charge（SOC） of the battery is below 95%, the polynomial curve is used as the control target for the torque characteristic of the driving motor, otherwise, the required torque is replaced by hydraulic braking torque to keep the same deceleration. The co-simulation of Matlab/Simulink/Stateflow and AVL CRUISE, as well as the hardware-in-loop experiment combined with d SPACE are carried out to verify the effectiveness and the real-time performance of the control algorithm. The results show that the EV with coasting braking control system has similar driving feeling to that of the reference vehicle, meanwhile, the battery SOC can be increased by 0.036% and 0.021% in the initial speed of 100 km/h and 50 km/h, respectively. The proposed control algorithm for EV is beneficial to improve the driving feeling in coasting mode, and it also makes the EV has the assistant braking function.

STRATEGY FOR DIESEL ROTARY ENGINE WITH COMMON RAIL INJECTION SYSTEM

A direct injection low compression ratios diesel rotary engine is designed and studied to find the appropriate application of the electronic controlled high pressure common rail injection system. Current development focuses on the applied fuel injection and ignition strategies, especially concerning the combustion configurations of injectors, ignition source, and combustion chamber. The prototype engine, equipped with Bosch common rail system and high performance electronic control unit （ECU）, is designed correspondingly. Studies show that the integration of a common rail injection system and the main and pilot duel injectors configurations, assisted with glow plug ignition device and flexible ECU, represents a promising approach to improve the potential of the low compression ratios diesel rotary engine. Currently the engine can run at 6 kr · min^-1 steadily and the power is about 68 kW/（4 kr ·min^- 1）.

SIMULATION IN THERMAL DESIGN FOR ELECTRONIC CONTROL UNIT OF ELECTRONIC UNIT PUMP

The high working junction temperature of power component is the most common reason of its failure. So the thermal design is of vital importance in electronic control unit （ECU） design. By means of circuit simulation, the thermal design of ECU for electronic unit pump （EUP） fuel system is applied. The power dissipation model of each power component in the ECU is created and simulated. According to the analyses of simulation results, the factors which affect the power dissipation of components are analyzed. Then the ways for reducing the power dissipation of power components are carried out. The power dissipation of power components at different engine state is calculated and analyzed. The maximal power dissipation of each power component in all possible engine state is also carried out based on these simulations. A cooling system is designed based on these studies. The tests show that the maximum total power dissipation of ECU drops from 43.2 W to 33.84 W after these simulations and optimizations. These applications of simulations in thermal design of ECU can greatly increase the quality of the design, save the design cost and shorten design time

COMPOSITIVE EMISSION CONTROL SYSTEM OF GASOLINE VEHICLE

The working principle of a kind of compositive emission control system is inquired into, which includes exhaust heater, secondary air supplement, exhaust gas recirculation （EGR）, thermal reactor and catalytic converter, etc. The purification effect of CO, HC and NOx emission of the gasoline spark ignite （S.I.） engine is studied. The entire vehicle driving cycle tests based on the national emission standard and a series of the gasoline engine-testing bench tests including full load characteristic experiment, load characteristic experiment and idle speed experiment are done. The results show that the system has a very good emission control effect to CO, HC and NOx of gasoline engine. The construction of the system is very simple and can be mounted on the exhaust pipe conveniently without any alteration of the vehicle-use gasoline engine.

基于安康控泄的蜀河水电站施工导流洪水风险控制

在水利水电工程施工导流中,由于投资和临时建筑物规模等原因,导流标准不可能被定的太高。因此如何保证导流施工期安全生产,应对超标准洪水,降低导流风险具有重要的理论和工程应用价值。本文以蜀河水电站施工导流为例,在对水库防洪风险和施工导流风险研究的基础上,提出利用上游已建水库控泄减小下游施工导流风险的方法,在不增加安康水库自身防洪风险的前提下,给出了其临时调度规则。最后,对既考虑区间入流又考虑上游水库控泄要求的情况,引入组合概率方法,计算下游施工导流风险。风险分析结果表明这种方法安全可行,可有效降低蜀河各施工期导流风险。

汽车安全气囊控制系统的优化设计

利用计算机辅助工程(CAE)技术对汽车安全气囊控制系统进行仿真分析与改进,使各参数达到目标值,是新型安全气囊控制系统在工程化设计阶段的重要内容。首先,建立基于ARM Cortex内核的安全气囊控制系统仿真模型;然后在台车试验数据的基础上,采用MADYMO软件进行CAE仿真,对X方向加速度进行了重点分析,进而校准了仿真模型;最后,通过调整安全气囊排气孔等参数,降低了对驾驶员头部的伤害值,进一步提高了汽车的安全性能。

腰椎融合中自体髂骨植骨与骨形态发生蛋白2比较的Meta分析

背景:骨形态发生蛋白2作为自体髂骨的替代已被广泛应用于临床及相关试验中。目的:评估腰椎融合中骨形态发生蛋白2的有效性和安全性。方法:检索2015年9月前中国生物医学文献数据库、Medline、Embase及Cochrane Central Register of Controlled Trial等数据库中,有关腰椎融合中骨形态发生蛋白2与自体髂骨植骨效果比较的随机对照试验,采用Cochrane系统进行Meta分析。结果与结论:共纳入14篇随机对照试验,总共1 613例患者。Meta分析结果显示,骨形态发生蛋白2组二次手术率、手术时间少于自体髂骨植骨组(P≤0.01),融合率高于自体髂骨植骨组(P≤0.01);两组间总体疗效、并发症、术中出血量、住院时间、患者满意度及术后工作情况等比较差异均无显著性意义。基于有限的证据,相较于自体髂骨植骨,骨形态发生蛋白2治疗腰椎退行性疾病并没有显著的优越性,评估骨形态发生蛋白2应用于腰椎融合手术的有效性和安全性,需要更多高质量的并有长期随访的随机对照试验。

特种气幕消融效率的配方控制研究

气泡消融效率是衡量舰船特种气幕性能最重要的技术指标。鉴于气体配方是影响消融效率的一个重要人为可控因素,首先从理论上分析了由主剂、添加剂组成的四种典型配方对消融效率控制的影响,研究了消融效率的配方控制原理;进而通过专门的实验研究,证实了特种气幕的消融效率可通过控制材料配方中的气体成分来有效实现的技术途径。研究结论对特种气幕技术的实现和运用具有实际意义。

Protection against water or mud inrush in tunnels by grouting:A review

Grouting is a major method used to prevent water and mud inrush in tunnels and underground engineering. In this paper, the current situation of control and prevention of water and mud inrush is summarized and recent advances in relevant theories, grout/equipment, and critical techniques are introduced. The time-variant equations of grout viscosity at different volumetric ratios were obtained based on the constitutive relation of typical fast curing grouts. A large-scale dynamic grouting model testing system （4000 mm × 2000 mm × 5 mm） was developed, and the diffusions of cement and fast curing grouts in dynamic water grouting were investigated. The results reveal that the diffusions of cement grouts and fast curing grouts are U-shaped and asymmetric elliptical, respectively. A multi-parameter real-time monitoring system （＆#981; = 1.5 m, h = 1.2 m） was developed for the grouting process to study the diffusion and reinforcement mechanism of grouting in water-rich faulted zone. A high early strength cream-type reinforcing/plugging grout, a high permeability nano-scale silica gel grout, and a high-expansion filling grout were proposed for the control of water hazards in weak water-rich faulted zone rocks, water inrush in karst passages, and micro-crack water inrush, respectively. Complement technologies and equipment for industrial applications were also proposed. Additionally, a novel full-life periodic dynamic water grouting with the critical grouting borehole as the core was proposed. The key techniques for the control of water inrush in water-rich faulted zone, jointed fissures and karst passages, and micro-crack water inrush were developed.