Bruno Jeanneret

Switched Causal Modeling of Transmission With Clutch in Hybrid Electric Vehicles

Certain difficulties arise when attempting to model a clutch in a power train transmission due to its nonlinear behavior. Two different states have to be taken into account-the first being when the clutch is locked and the second being when the clutch is slipping. In this paper, a clutch model is developed using the energetic macroscopic representation, which is, in turn, used in the modeling of complete hybrid electric vehicles (HEVs). Two different models are used, and a specific condition defining the commutation between both models with respect to the physical energy flow is proposed. A Petri net is employed to activate one of the models, depending on the clutch state (locked or slipping). This model allows us to implement without difficulty a simulation of the clutch with a relatively short computation time.

Model simulation, validation and case study of the 2004 THS of Toyota Prius

For hybrid vehicles, it is difficult to obtain realistic component models and actual interaction between subsystems without carrying out experiments. INRETS has performed a coupled approach associating simulation using its in house VEHLIB software together with experimental validation. This paper highlights the evaluation and modelling of the Toyota Hybrid Systems (THS) used in the 2004 Prius vehicle. First, the ICE, battery, boost converter, and strategy evaluation and validation process to obtain a useful model of the vehicle are examined. Then examples of application are presented concerning energy flow in the vehicle and engine operation compared to a conventional car.

HEVs Comparison and Components Sizing Using Dynamic Programming

This paper presents a backward approach for HEVs modelling with a global optimization method. This method allows to determine the maximal potential gain in terms of CO2 emission for a given HEV. It is then applied to size and compare two hybrid architectures and conventional vehicles. Finally a comparison on measurement, classical forward approach and optimized backward approach is performed on the Toyota Prius 2004 vehicle.

Optimal management of electric vehicles with a hybrid storage system

This paper presents a comparison between two offline optimisation methods for energy management applied to electrical vehicle with one electrical machine and fed by a hybrid storage system composed of batteries and ultra-capacitors. After a short presentation of the two methods, they are applied and compared to the case of an electric micro bus.

Switched Causal Modeling of Transmission with Clutch in Hybrid Electric Vehicles

The modeling of a clutch in a powertrain transmission is a sensitive issue because of its non-linear behavior. Two different states have to be taken into account: clutch locked and slipping. Two different models are then used and a specific condition defines the commutation between both models with respect to the physical energy flow. An application to parallel Hybrid Electric Vehicles (HEV) is then presented. Energetic Macroscopic Representation (EMR) is used to organize the numerous blocks required. A Petri net is employed to activate a model according to clutch state (lock and slip).

Trajectory optimisation for eco-driving - an experimentally verified optimisation method

Eco-driving is an immediately applicable way to reduce fuel consumption in road vehicles by changing vehicle operation such that system efficiency is maximised. In order to identify the maximum potential of eco-driving a numerical method that computes the optimal velocity profile for a specified mission is presented here. An inverse vehicle model is presented to calculate energy consumption as a function of acceleration and velocity. Given the non-linear nature of the problem and the varying constraints the dynamic programming method was chosen to solve the optimisation problem. An iterative approach, combining dynamic programming with advanced root finding methods is proposed to reduce computational time. Using hardware-in-the-loop settings the theoretically optimal velocity profiles were tested on an engine test bench. With this the potential gains of eco-driving were verified and important factors for eco-driving were identified.

Validation of Mechanical Transmission with Clutch using Hardware-In-the-Loop Simulation

A hardware-in-the-loop (HIL) simulation of a conventional vehicle system is developed for experimental validations of clutch modelling. Two different states have to be taken into account in this system: clutch locked and slipping. Two different models are then used and a specific condition defines the commutation between both models with respect to the physical energy flow. Energetic macroscopic representation (EMR) is used to organize the numerous blocks required. A Petri net is employed to activate a model according to clutch state (lock and slip). The HIL is based on a controlled IM drive, which imposes the same behaviour of the mechanical power-train to the clutch. A flexible and dynamical model of the whole system is used and simulation results are provided with regard to the experimental results.

Inversion-based control of a vehicle with a clutch using a switched causal modelling

The modelling of a clutch in a power train transmission is a delicate process because of its non-linear behaviour. Two different states have to be taken into account: when the clutch is locked and when the clutch is slipping. Moreover the clutch has often to be controlled automatically in parallel hybrid electric vehicles (HEVs). An energetic macroscopic representation (EMR) of a clutch system has been developed. Both clutch states are genuinely taken into account in a physical way. In this article, EMR leads to organise the control scheme of the clutch system using an inversion methodology. An experimental validation is provided on a conventional vehicle before being implemented on parallel HEVs. Experimental results are provided to validate the clutch model and the inversion-based control.