Xiaohong Jiao

An Adaptive Servo Control Strategy for Automotive Electronic Throttle and Experimental Validation

In order to achieve higher precise positioning of the throttle plate, an adaptive servo control strategy is presented for the electronic throttle control system. Compared with the existing results on the electronic throttle control schemes, in this paper, the throttle valve reference tracking controller comprises a proportional-integral-derivative-type feedback controller with adaptive gain parameters, an adaptive feedforward compensator, and adaptive nonlinearity compensators for friction, limp-home (LH), and backlash. The closed-loop controller is realized by only utilizing the information of the throttle valve position measured by a cheap potentiometer of low resolution. The theoretical proof and analysis show that the designed throttle control system can ensure fast and accurate reference tracking of the valve plate angle in the case of the uncertain parameters related to production deviations, variations of external conditions and aging, and the effects of transmission friction, return-spring LH, and gear backlash nonlinearity with uncertain parameters. Moreover, the capability of the adaptive controller to preserve the transient performance and accuracy is evaluated in both simulation and experiment.

Model-Based Stochastic Optimal Air–Fuel Ratio Control With Residual Gas Fraction of Spark Ignition Engines

In this paper, a stochastic optimal control scheme for the air-fuel ratio is proposed, which considers the cyclic variations of the residual gas fraction (RGF). Initially, a cylinder pressure-based measurement of the RGF is derived by following the physics of inlet-exhaust process. Then, a dynamical model is presented to describe the cyclic variation of the air charge, fuel charge, and combustion products under a cyclically varied RGF, where the RGF is modeled as a Markovian stochastic process. Using this model, a feedback control law is derived, which optimizes the quadratic cost function in the stochastic sense with respect to the stochastic property of the residual gas. The cost function reflects the tradeoff between the accuracy of the regulation of the air-fuel ratio with the fluctuation in the fuel injection. Finally, a sampling process-based statistical analysis for the RGF is presented based on the experiments conducted on a full-scaled gasoline engine test bench, and the proposed control law is validated based on a numerical simulation and experiments.

Continuation/GMRES Method based Nonlinear Model Predictive Control for IC Engines

Abstract This paper presents a model-based receding horizon optimal control algorithm for the engine speed tracking control. A mean-value model including the air intake dynamics and the rotational dynamics is exploited in the tracking controller design, which is calibrated based on the physical rules combined with curve fitting techniques. Based on this mean-value model, the dynamical model of the speed tracking error is derived for any given speed command. The design problem is reduced to the receding horizon control problem under the constraint of the tracking error dynamics. The online computational algorithm based on C/GMRES approach is adopted to solve this nonlinear receding optimal problem. Finally, simulation and experiments results demonstrate the satisfactory tracking performance by using the proposed controller.

L 2 -gain analysis and feedback design for discontinuous time-delay systems based on functional differential inclusion

A functional differential inclusion-based approach to L2-gain analysis and feedback control problems is presented for a class of discontinuous time-delay systems. Motivated by Filippov solution in the differential equations with discontinuous right-hand side, definition of the discontinuous time-delay systems forced by external signals is introduced, and a description of L2-gain property in the sense of the solution concept is given. Then, a condition such that a given discontinuous time-delay system has L2-gain less than a given level and the unforced system is stable in the sense of Filippov solution is presented based on a delay-dependent partial differential inequality. Furthermore, using the presented condition, a design method of state feedback controller is shown such that the closed-loop system satisfies the L2-gain constraint and asymptotical stability. Numerical examples are presented to demonstrate the presented theoretical results.

An Energy-Shaping Approach with Direct Mechanical Damping Injection to Design of Control for Power Systems

Recently, the investigation of design approaches to nonlinear control, which can thoroughly exploit the structure and the properties of the physical systems, has been given much attention due to the designed controllers with relatively simple form and effective operation. And it has been shown that for the mechanical and electromechnical systems, by incorporating the Hamiltonian structure into passivity-based control design techniques, the controllers based on physical considerations can be obtained [1],[2],[3]. This design idea has been successfully realized alized in the control of power systems and a lot of achievements have been gotten (see e.g. [1]–[9). In [4], the fact that the power system with excitation control is a Hamiltonian structure is exploited by selecting a storage function constructed by system potential and kinetic energy and an appropriate passivating output on the basis of physical arguments. Along this research line, the excitation control problem for multi-machine power systems has been investigated in [5],[6]. Moreover, an adaptive L 2 disturbance attenuation controller based on Hamiltonian structure has been provided for power systems in [7].

PID Control with Adaptive Feedback Compensation for Electronic Throttle

Abstract In order to achieve higher precise positioning of the throttle plate, an adaptive control strategy, which comprises a PID controller, a feedforword compensator and an adaptive nonlinearity compensator, is presented for the electronic throttle control system. Compared with the existing results on the electronic throttle control schemes, in this research the proportional-integral-differential gain coefficients can be determined according to the desired tracking transient performance and the adaptive nonlinearity compensator is derived for friction, limp-home and backlash. The theoretical proof and analysis show that the designed throttle control system can ensure fast and accurate reference tracking of the valve plate angle in the case of the effects of transmission friction, the return spring limp-home and gear backlash nonlinearity with uncertain parameters and external disturbance. Moreover, the simulation results on the test bench of electronic throttle demonstrate the capability of the proposed controller to achieve asymptotical reference tracking, while preserving the transient performance, like settling time and overshoot within the acceptance requirements.

Excitation Control Based Energy-Shaping with Direct Mechanical Damping Injection for Transient Stability Improvement of Power Systems

In this paper, a novel energy-shaping design method is provided for excitation controller of power systems, which is carried out by directly injecting the compensation damping into the mechanical damping. This design method utilizes the transient energy function with the physical properties of power system, and the adjusted parameters of the designed controller have directly corresponding relation to the physical meaning of the mechanical damping and electrical damping of power system. In addition, to further enhance the transient stability, considering the possible variation in the transmission line and uncertainties in physical parameters, an adaptive excitation controller is also designed by employing the direct mechanical damping injection. It is shown that the proposed excitation controller can make the system have better dynamic properties and large stability margin even in the case with the permanent fault on transmission line and the turbine failure. And, for illustrating the effectiveness of the proposed controller, the simulation comparison results with the traditional energy-shaping approach are presented.

Adaptive state feedback control of nonlinearly parameterized time-delay systems

Abstract The problem of adaptive stabilization is investigated for nonlinearly parameterized uncertain nonlinear time-delay systems. An adaptive controller is developed on the basis of Lyapunov-Razumikhin stability theory, which can guarantee the global uniform ultimate boundedness of all the signals in the resulting closed-loop dynamical system. The essential of the proposed design is that a new parameter variable is introduced into the adaptive controller instead of the conventional parameter variable in order to deal with the obstacle brought by Razumikhin condition. With the help of the provided design method, an adaptive backstepping design scheme based on Lyapunov-Razumikhin function is proposed for general nonlinearly parameterized time-delay systems without any restriction.