B.K. Powell

Dynamic modeling and control of hybrid electric vehicle powertrain systems

This paper describes the mathematical modeling, analysis, and simulation of a dynamic automatic manual layshaft transmission and dry clutch combination powertrain model, and corresponding coordinated control laws synthesized using a conventional SI ICE powerplant-alternator combination, a dry clutch and manual transmission/differential, variable field alternator, brakes, and complete vehicle longitudinal dynamics with tire-road interface characterization. The conventional power train model is validated using experimental test data confirming accurate emulation of dynamic components of the pre-hybridized vehicle. In addition, the development of dynamic series and parallel hybrid electric vehicle (HEV) powertrain models and corresponding coordinated control laws are described. A discussion of the key issues associated with coordinated control law development is provided. Simulations of the dynamic behavior of two types of series HEVs are shown.

Nonlinear Low Frequency Phenomenological Engine Modeling and Analysis

The paper contains a bibliography and discussion of recent activity in nonthermodynamic (low frequency) internal combustion engine model development where spark advance, fuel, throttle, and exhaust gas recirculation are the elected control variables. Modeling considerations are delineated and the modeling relationship to experimental verification is discussed. Examples with explicit methods of parameter determination and dynamic validation are presented.

Discrete Simplified External Linearization and Analytical Comparison of IC Engine Families

A general, nonlinear spark ignition engine model is presented. Speed dependent discretization is employed to develop a linearized formulation for four and six cylinder port fuel injected engine representations. The methods presented provide a foundation for the application of classical or modern control techniques to internal combustion (IC) engine related control problems.

Modern control applications in idle speed control

The automotive engine idle-speed regulation problem is one which lends itself to the application of a variety of control theory techniques. The process is distributed and nonlinear with a combination of continuous and discrete elements. There are known and unknown disturbances with both periodic and random process noise. The process is time varying over both short and long time intervals. This paper discusses the application of modern and classical control techniques to the idle speed regulation problem. The use of nonlinear simulation, discrete identification and in-vehicle control synthesis provides a framework for systematic control system design tradeoffs.

Parallel hybrid electric vehicle dynamic model and powertrain control

Contains a description of mathematical modeling, analysis, and simulation in an iterative process including development of parallel hybrid electric vehicle (PHEV) hardware, system performance measures, computer control software, and complete PHEV powertrain system synthesis. A PHEV is synthesized using a conventional spark ignited (SI) internal combustion engine (ICE) power plant-alternator combination, a dry clutch, and manual transmission/differential with an AC induction traction motor attached after the differential. An operating strategy for this PHEV is presented.

Modeling and Analysis of an Inherently Multi-Rate Sampling Fuel Injected Engine Idle Speed Control Loop

This paper develops a model for the idle speed control of a six cylinder. electronically fuel injected, spark ignition engine. The inherently discrete microprocessor based fuel controller is not constrained to operate at the engines natural sampling rate, resulting in a hybrid (continuous-discrete) multi-rate system. A method for evaluating the stability of the system is developed.

Control system and dynamic model validation for a parallel hybrid electric vehicle

Contains a description of mathematical modeling, analysis, and simulation in an iterative process including development of parallel hybrid electric vehicle (PHEV) hardware, system performance measures, computer control software, and complete PHEV powertrain system synthesis. A PHEV is synthesized using a conventional spark ignited (SI) internal combustion engine (ICE) power plant-alternator combination, a dry clutch, and manual transmission/differential with an AC-induction traction motor attached after the differential. An operating strategy for this PHEV is presented. Simulations and test data are presented to demonstrate model validation.

Hardware-in-the-loop vehicle and powertrain analysis and control design issues

Powertrain and vehicle control systems are rapidly becoming extremely sophisticated. In order to maintain product technology competitiveness, minimize product and control system complexity, and contain development costs and timing, correspondingly more sophisticated control system development tools and methodologies are required. Hardware-in-the-loop simulation technology offers promise to bridge the challenging gap between system modeling and actual prototype system hardware implementation. This paper contains a discussion of some of the principal analytically related issues associated with a HIL powertrain laboratory.

Optimal idle speed control of an automotive engine

An optimal control algorithm is derived to solve the idle speed control problem for an automotive engine. The system describing the engine dynamics during idle consists of nonlinear algebraic-ordinary differential equations with variable-time-delay elements. Unlike many previous studies, no approximation is made to the variable-time-delay term in the equations. Instead, we use a special procedure to compute this variable-time-delay term accurately. The results show that the optimal control algorithm derived can deliver highly efficient controls to the system. Compared with the conventional control methods, the optimal control algorithm provides a versatile and systematic way to idle speed control of automotive engines.

Computer model for a parallel hybrid electric vehicle (PHEV) with CVT

A complete dynamic vehicle model for a parallel hybrid electric vehicle (PHEV) equipped with a continuously variable transmission (CVT) is developed and presented. The PHEV has a post-transmission electric motor. The model is intended to represent the dominant dynamics relating to the control of the overall system. Both analytical and empirical techniques are used in developing the model. The modeled components include: internal combustion engine, engine clutch, CVT, electric motor, lead-acid battery, vehicle driveline, hydraulic brakes, and vehicle longitudinal and tire dynamics. A vehicle computer control module as well as component controllers, sensors and control mechanisms are also modeled. The model is implemented in the Matlab/Simulink environment. The simulation results are presented.