Testing Possibilities of Control Algorithms for Hybrid Electric Vehicles GHEORGHE LIVINŢ, VASILE HORGA, MIHAI ALBU and MARCEL RĂŢOI Faculty of Electrical Engineering “Gh.Asachi” Technical University of Iaşi Blvd. D. Mangeron, nr. 53, 700050, Iaşi ROMANIA Abstract: - This paper presents a methodology of rapid testing for different control algorithms of electrical drives with inverter-fed induction motors used for the propulsion of hybrid electric vehicles. For analysis, modeling and off-line simulation of the vehicle operations conditions, and also for the testing in real time of the control algorithm performance certain hardware/software products COTS (ADVISOR, DS1104, ControlDesk) are used. The emulation of the real traffic conditions, obtained by off-line simulations, are replicated with a torque controlled dc machine, which load the induction machine under test. Key-Words: - Control algorithms, real time simulation, hybrid electric vehicle, SOC measurement 1 Introduction Any vehicle that has more than one power source can be classified as a hybrid electric vehicle (HEV), but most frequently the term is used for a vehicle which combines electric drive with a heat engine using a fossil-fuel energy source. HEVs can be classified in: a) all-electric vehicles using two different types of battery, or a fuel-cell and a battery, or a battery and a supercapacitor, b) electric vehicles (EV) in which the main electric-drive battery is supplemented in peak-load condition by power stored in a flywheel or in a hydraulic accumulator, c) hybrid vehicles in which the battery is used together with a heat engine to provide high efficiency drive. There are also two major configurations in which the components of a hybrid system can be arranged: the series hybrid in which the drive wheels are propelled only by the electric machine, and the parallel hybrid in which the drive wheels transmission power is obtained from electric and/or heat engine. Development of hybrid electric vehicle has been focusing on reducing emission gas and on operation with better fuel economy. With HEVs, fuel economy is achieved in two major areas: a) regenerative braking recovers a significant fraction of the vehicle kinetic energy in the battery. When the driver accelerates later, this energy is returned as essentially free power. In stop-and-start driving, the energy recovered can boost efficiency by about 20 percent [1]; b) the engine shuts down during stops and low-power driving, and so increases the average efficiency in urban driving. It improves overall efficiency by about 40 percent. In today HEVs the induction and permanent magnet synchronous machines are used the most. The electrical machine is capable of both producing and absorbing mechanical power. Based on the driver’s power request and the state of charge (SOC) of the battery, the power management algorithm determines whether electrical machine should contribute power to, or absorb power from the crankshaft. In order to derive benefits from a hybrid powertrain, the power management becomes a major concern and deals with the decision making regarding the power split between the thermal and electrical path, taking into account the current SOC of the energy storage unit. The objective is to minimize fuel consumption while the driving schedule on demand is satisfied. A number of algorithms have been proposed in the literature based on a priori knowledge of the driving schedules. The pressure of increased complexity in the design and verification process, involved with the testing of complex electronic and component systems, forced the automotive industry to investigate and invest in better testing methodologies. Recently, the automotive industry has seen a great change in the implementation process of new control systems, with the integration of rapid development tools for new ideas and products. Perhaps the bigger change, however, is the adoption of some rapid-prototyping concepts for vehicle and component testing and validation. Proceedings of the 2nd WSEAS International Conference on Dynamical Systems and Control, Bucharest, Romania, October 16-17, 2006 47