基于RBF神经网络的柴油机控制模型辨识方法

针对柴油机电子调速器设计开发中需解决的高实时性模型建模问题,对基于RBF神经网络的柴油机建模方法进行研究,在Matlab/Simulink环境设计辨识模型和算法,以PA6柴油机为例进行了模型辨识实验验证。结果表明,本文方法具有逼近精度高、响应速度快等优点。

新型核级电子调速控制器的启动功能验证方法

为确保某新型核级电子调速控制器应用的安全可靠,对其首次应用于应急机组时的启动控制方法开展研究。建立半实物仿真平台作为验证工具,并通过真实试验数据和柴油机参数建立柴油机模型,保证半实物仿真平台与实际柴油机的性能指标相接近。调整新型核级电子调速控制器的启动控制策略与现产品电子调速控制器一致。将新型核级电子调速控制器的启动功能在半实物仿真平台上验证,确保半实物仿真试验启动试验数据与原应急机组启动试验数据接近。在应急柴油机上进行启动功能试验,实机试验结果表明启动性能满足应急柴油机组要求,实机启动试验数据与半实物仿真试验数据基本一致。

基于NI产品的电控单元硬件在环测试系统开发

利用SIT接口工具包,将基于SIMULINK平台自主开发的涡轮增压共轨柴油机仿真模型编译为DLL文件下载到NI-PX I8106实时平台,利用NI-PX I 7831R板卡的高速数据采集和发生功能,首先对控制单元输出的轨压控制信号、喷油脉冲信号进行实时采集处理获得仿真模型计算所需的输入变量,模型根据输入经实时运算得出发动机状态值,由板卡实现柴油机飞轮、凸轮、轨压、冷却水温、增压压力等信号的模拟输出。开发了基于PX I-8464的CAN通信程序,与ECU实时交互数据,计算模型的控制量输入可在板卡实际采集量和ECU计算量之间切换,方便了测试系统调试。利用SIT集成接口将以上3部分集成实现了软硬件的闭环联合仿真,并结合自主开发的共轨电控单元对系统进行了实际测试,效果良好。

A Practical Approach of Developing Mathematical Model for All Speed Governors

The paper introduced a special approach for diesel’s all-speed-governor modeling, which, in some cases, could solve the knotty problem frequently met in computer simulation of diesel propulsion system or diesel generating set. Suppose that it is hard to get a control-oriented governor mathematical model when the general approaches, the analytical approach or the experimental approach, are applied, and that an open-loop step response of the diesel engine and its system is available by means of computer simulation, the critical three parameters of a governor mathematical model, the proportional gain K_p, integral time constant K_i, and derivative time constant K_d, can be determined by use of PID tuning method which are widely applied in industrial process control. This paper discussed the train of thought of the approach, precondition, procedure, several modifications of the classical PID model, and some points for attention. A couple of case studies were given to demonstrate the effectiveness of this approach.

Simulation of quasi-dimensional model for diesel engine working process

In order to satisfy the demand of validity and real time operating performance of diesel engine model used in hardware-in-the-loop simulation system,a simplified quasi-dimensional model for diesel engine working process was proposed,which was based on the phase-divided spray mixing model.The software MATLAB/Simulink was utilized to simulate diesel engine performance parameters.The comparisons between calculated results and experimental data show that the relative error of power and brake specific fuel consumption is less than 2.8%,and the relative error of nitric oxide and soot emissions is less than 9.1%.At the same time,the average computational time for simulation of one working process with the new model is 36 s,which presents good real time operating performance of the model.The simulation results also indicate that the nozzle flow coefficient has great influence on the prediction precision of performance parameters in diesel engine simulation model.

Design and optimization of exhaust gas aftertreatment system for a heavy-duty diesel engine

Diesel engines meeting the latest emission regulations must be equipped with exhaust gas aftertreatment system,including diesel oxidation catalysts(DOC),diesel particulate filters(DPF),and selective catalytic reduction(SCR).However,before the final integration of the aftertreatment system(DOC+DPF+SCR)and the diesel engine,a reasonable structural optimization of the catalytic converters and a large number of bench calibration tests must be completed,involving large costs and long development cycles.The design and optimization of the exhaust gas aftertreatment system for a heavy-duty diesel engine was proposed in this paper.Firstly,one-dimensional(1D)and threedimensional(3D)computational models of the exhaust gas aftertreatment system accounting for the structural parameters of the catalytic converters were established.Then based on the calibrated models,the effects of the converter’s structural parameters on their main performance indicators,including the conversion of various exhaust pollutants and the temperatures and pressure drops of the converters,were studied.Finally,the optimal design scheme was obtained.The temperature distribution of the solid substrates and pressure distributions of the catalytic converters were studied based on the 3D model.The method proposed in this paper has guiding significance for the optimization of diesel engine aftertreatment systems.

DPM dispersion inside a single straight entry using dynamic mesh model

Three-dimensional simulations of diesel particulate matter （DPM） distribution inside a single straight entry for the Load-Haul-Dump loader （LHD）-truck loading and truck hauling operations were conducted by using ANSYS FLUENT computational fluid dynamics software. The loading operation was performed for a fixed period of 3 min. The dynamic mesh technique in FLUENT was used to study the impact of truck motion on DPM distribution. The resultant DPM distributions are presented for the cases when the truck were driving upstream and downstream of the loading face. Interesting phenomena were revealed in the study including the piston effect, layering of DPM in the roof region, and backflow of diesel exhaust against ventilation. The results from the simulation can be used to determine if the areas inside the face area and straight entry exceed the current U.S. regulatory requirement for DPM concentration （〉160 pg/m3）. This research can guide the selection of DPM reduction strategies and improve the working practices for the underground miners.

A Database of Selected Marine Diesel Engines for Diagnostic Needs

The article describes an electronic database of selected marine piston combustion engines created for diagnostic purposes. The database was made for vessels of the biggest Polish shipowner. It is used for archiving and comparing measured parameters of diagnosed engines with model parameters. To facilitate the search for and use of required data, they have been collected and catalogued. For this purpose the database has been prepared by using a computer program included in the Microsoft Office suite. The database search relies on the details concerning the type of vessel. The fields displayed include such items as the year and place of construction, the parameters of the ship, flag, etc.. For each vessel special forms are available for main and auxiliary engines, enabling easy and quick check of the necessary parameters during operation of the engine. The database contains parameters of the main propulsion and auxiliary engines, as well as model characteristics to help determine the diagnostics, prognosis and genesis.

Robust Intelligent Control Design for Marine Diesel Engine

This work deals with the nonlinear control of a marine diesel engine by use of a robust intelligent control strategy based on cerebellar model articulation controller （CMAC）. A mathematical model of diesel engine propulsion system is presented. In order to increase the accuracy of dynamical speed, the mathematical model of engagement process based on the law of energy conservation is proposed. Then, a robust cerebellar model articulation controller is proposed for uncertain nonlinear systems. The concept of active disturbance rejection control （ADRC） is adopted so that the proposed controller has more robustness against uncertainties. Finally, the proposed controller is applied to engine speed control system. Both the model of the diesel engine propulsion system and of the control law are validated by a virtual detailed simulation environment. The prediction capability of the model and the control efficiency are clearly shown.