Investigation in fuel consumption of a hybrid and conventional vehicle

R. Šmigins*, V. Pīrs and D. Berjoza

Latvia University of Life Sciences and Technologies, Faculty of Engineering, Motor Vehicle Institute, J. Cakstes blvd 5, LV3001 Jelgava, Latvia
*Correspondence: ruslans.smigins@llu.lv

Abstract:

During the last decade the introduction of more environmentally friendly technologies were raised more rapidly by the decline in the global fossil energy resources and the increased negative environmental impact of conventional vehicles. One of such technology is the hybrid, which is currently making the transition from conventional vehicle with internal combustion engine to an electric vehicle. At this time there exist a lot of offers of such vehicles from different manufacturers, but there do not exist many researches connected with real hybrid performance in different road cycles and conditions allowing evaluate its real economical performance.
This research was realized with the aim to evaluate performance and fuel consumption of hybrid electric vehicle and its conventional internal combustion engine analogue in laboratory conditions. Tests were realized with two new Toyota Yaris vehicles in Alternative Fuels and Research Laboratory on chassis dynamometer MD-1750 using AVL KMA Mobile system. The results showed better adaptation of Toyota Yaris Hybrid to urban operation, demonstrating 21.3% lower fuel consumption than Toyota Yaris conventional gasoline vehicle, accordingly 7.29 and 8.84 L (100 km)^-1.

Key words:

Automated Measuring Station for Accumulator Testing

S. Papezova¹* and V. Papez2

¹Czech University of Life Sciences in Prague, Faculty of Engineering, Department of Electrical Engineering and Automation, Kamycka 129, CZ 165 21, Prague 6 ˗ Suchdol, Czech Republic
2Czech Technical University in Prague, Faculty of Electrical Engineering, Department of Electrotechnology, Technicka 2, CZ 166 27 Pague 6, Czech Republic
*Correspondence: papezovas@tf.czu.cz

Abstract:

The paper describes the design and implementation of the system allowing the testing of the lithium-iron-phosphate (LiFePO₄) cell parameters during long-term loading. Manufacturers and retailers, in particular, accentuate their beneficial properties – the possibility of charging and discharging by high currents, minimum influence of the discharge time on capacity, long durability. At the same time, their operational conditions are a lot more strictly defined than those for other types of accumulators. The proposed testing system enables loading the accumulators, consisting of several cells, by periodic discharging and charging processes with various operating currents and various levels of cell discharging. The charging and discharging process control is fully automated; the measuring of the cell operational state is performed automatically during charging and discharging. The data is recorded, and continuously evaluated for the purposes of process management. The measurements enable the comparison of the catalogue data with the parameters of the real products. The testing system design is based on the application of a digital control block, which is completed with an analog control block. The core of the digital control unit is a control computer equipped with a multifunctional input-output card and an array of logically controlled circuit breakers. An accumulator management algorithm, implemented as a control program of the computer, ensures the operation of the accumulator in subsequent charging and discharging periods. The actual accumulator control is based on the evaluations of voltage levels at the cell terminals.

Key words:

Ah capacity, LiFePO4 accumulator, limit parameters, testing