Kota Sata

Predictive control for high-EGR SI engines without misfire via flow-based design

This paper introduces a predictive controller that maximizes the EGR ratio in SI engine cylinders and prevents misfires at all throttle operations. However the predictive control problem for the EGR value angle is a nonlinear time-varying one. Therefore, in the proposed controller, the problem is transformed into a time-invariant quadratic one for the EGR flow through the intake valve. As a result, only one controller has to be designed for the entire engine operating range. The effectiveness of the proposed controller is demonstrated using a well-calibrated simulator.

Effect of Transient Residual Gas Fraction for Gasoline Engines

The residual gas fraction (RGF) greatly affects misfiring, the heat release pattern of combustion, auto-ignition, the NOx emission. There is a possibility that RGF estimation improves the accuracy of engine control. This paper describes a transient RGF estimation based on a physical model and the effect of RGF on transient air fuel ratio. This study shows the auto-correlation function of RGF takes negative values at k = 1 (k: sampling number) and the residual gas causes the dynamic effect of air-fuel ratio calculated from the composition of burned gas.

Statistical Model and Control of Residual Gas Mass in Gasoline Engines

Abstract To attenuate the cyclic variation of the residual gas mass, a feedback regulator for the residual gas mass is designed based on a dynamic model with stochastic property. The dynamic model is developed in accordance with the physics, where the residual gas fraction (RGF) as a crucial system parameter is modeled as a stochastic process with Markov property. The regulator is given by utilizing control design technology for the discrete-time jump system. The performances of closed-loop system with the proposed controller, which is presented by the experiments conducted on a full-scaled gasoline engine test bench, show that the residual gas mass has narrower dispersion under two different working conditions.

Parallel design of control systems utilizing dead time for embedded multicore processors

This paper presents a parallelization method utilizing dead time to implement higher precision control systems on multi-core processors. It is known that dead time is hard to handle with in control systems. In our method, the dead time is explicitly represented as delay blocks of models such as Simulink. Then, these delay blocks are distributed to the overall systems with equivalent transformation, so that the system can be simulated or executed in pipeline parallel. With a spring-mass-damper model, our technique accomplishes ×3.4 performance acceleration on an ideal four-core simulation, and ×1.8 on cycle-accurate simulator of a four-core embedded processor as a threaded application on a real time operating system.