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This paper focuses on modeling of the heavy-duty vehicle drivetrain with automatic transmission by using dual clutch scheme. The planetary gear set in the automatic transmission is complicated structure and difficult to understand. The advantage of the dual clutch scheme is that it can be used to represent the complex planetary gear set intuitively, which is a great help to understand the gear shifting process. It is also suitable for being used in the controller due to its low order. Some conditions are required to convert the planetary gear set to the dual clutch model. The heavy-duty vehicle driveline can be converted to the dual clutch model due to its heavy engine and vehicle inertia. This paper also proposes system parameter estimation methods to represent the driveline model. The main parameters are lumped inertia, lumped gear efficiency, output shaft compliance and friction coefficient of clutches.

Demand for electrified vehicles is increasing due to increased environmental pollution regulations and interest in highly efficient vehicles. According to these demands, research on electrified vehicles equipped with Dual Clutch Transmission (DCT) has been actively conducted for the purpose of improving energy efficiency of electrified powertrain, maximizing acceleration performance, and increasing maximum speed. However, since DCT requires clutch to clutch shifting, it is difficult to control drive torque and slip speed using two clutch actuators and a power source input. In order to solve this, a study on a multivariable shift controller has been conducted. However, this study chose a heuristic planning method to control the two outputs. However, since the slip speed and drive torque are coupled, it is necessary to tune the reference for every shift scenario, as well as create unnecessary control inputs or degrade shift control performance.

This study mainly focuses on developing an accurate tracking controller for the self-energizing clutch actuator (SECA) system consisting of a DC motor with an encoder applied on the automated manual transmission (AMT). In the position-based actuation of the SECA, abruptly increasing torque near the clutch kissing point during the clutch engagement process induces control input saturation and jerky response when a conventional feedback controller is applied. The proposed work resolves such issue and significantly increases the control accuracy of the actuator through the development of an effective H-infinity controller. The control performance is shown to be more effective than a simple PID controller via simulation and experiments using an AMT test bench equipped with SECA aided by d-SPACE and Matlab/Simulink.

The regulation of NOx emission from a diesel engine is becoming stricter by the environmental agency and furthermore, EGR has been adopted to reduce NOx emission. Air flow control of a diesel engine combined with turbocharger and EGR is complicated because turbocharger and EGR are coupled physically. This paper examines the design of a model based control structure for diesel engine with a turbocharger and EGR. Model based control provides desirable control strategies from the physical analysis of an engine model. Air fraction and exhaust manifold pressure target based control simulation was conducted in this research. Engine is highly nonlinear and susceptible to uncertainties. To overcome this problem, a robust controller was designed by using a sliding mode control method.

This paper deals with the simplification and optimization methods in diesel engine control which is based on the air management system model of 1stage VTG and HP-EGR. Especially, simplified model based controller is suggested including more tracking performance of target values for comparison from previous multivariable sliding mode controller with intake and exhaust manifold output set. Moreover, in calculating desired exhaust manifold pressure, the simple process which only use target flow rates is suggested. There are fewer errors than general process's which have to add the target state process including the turbocharger parameter errors. Model based controller has assumption that mathematical model has to be very accurate, therefore, has to reflect the physical engine properties in every operating point. But, it is hard to satisfy this assumption because of the modeling uncertainties in mathematical point and a variety of environmental factor in real engine.

Automotive industry has been developing technologies to reduce exhaust emission. Moreover, developing an environmentally friendly diesel engine will become the most important issue in the future engine technology. A modern well-tuned diesel engine no longer smokes and the noise has been attenuated to more acceptable levels. In spite of these efforts, emission of particulates and nitrogen oxides (NOx) have not been equally successful. Therefore, the accurate control method of diesel engines is coming up in solving the problems related with NOx and PM. The diesel engine is a highly nonlinear system and the modeling parameters are changed significantly for different operating points. Therefore, it is very difficult to control the diesel engine system accurately. Every engine system model is actually composed of a variety of maps. And then, actuators like dc motors are controlled for transferring the appropriate flow rate to the manifolds.