German version
VDL Citea SLF 120 Hybrid
A newcomer in the Citea range from VDL Bus & Coach is the Citea SLF-120/hybrid – a serial hybrid Citea, equipped with reliable, proven technology. The Citea SLF-120/hybrid will be available as from the 4th quarter of 2011.
Objectives
The ambition has been to significantly reduce fuel consumption and the emissions of CO2, fine particulates and NOx. This is achieved by using an electric drive for the Citea SLF-120/hybrid. The diesel engine drives a generator that produces the electrical power. This electrical power is stored in batteries (supercaps) for later use or is used immediately to power the hub motors installed in the rear axle. The braking energy is also recovered and stored in these supercaps so the energy can be used again for driving. It is also possible to have the diesel engine shut off at bus stops and whenever else the bus comes to a standstill. Optionally, only the electric motors will be used when accelerating from a stop. This makes it possible to drive portions of a route using just electric power, producing zero emissions. An additional, and certainly not unimportant, environmentally-responsible aspect is that far less noise is produced.
Optimal hybrid city bus
When designing the VDL Bus & Coach serial hybrid concept, VDL Bus & Coach sought to achieve the ideal and optimal concept for a hybrid city bus. A number of aspects were very important in this decision-making process:
• The selected components had to be thoroughly proven and the best of their type to ensure the greatest possible reliability.
• The hybrid concept had to fit the modular construction method used for the Citea range so future developments could be easily integrated.
• There could be no negative impact on passenger comfort. The number of drive components had to be kept to an absolute minimum to achieve even greater noise reduction.
These considerations led to selection of a serial hybrid concept with components from Vossloh Kiepe, a 4 cylinder Cummins diesel engine and the electrically-driven rear axle from ZF. This was all done with the goal of achieving the most efficient configuration possible, maximum reduction of the emission of harmful substances and maximum fuel economy.
The Citea SLF-120/hybrid is available in 3 versions: the ‘Basic Hybrid’, the ‘Basic Zero Emission Hybrid’ and the ‘Advanced Zero Emission Hybrid’. With the latter version it is possible to drive a pre-established part of a route entirely on electric power, producing zero emissions.
Technology
The Citea SLF-120/hybrid is built with components from renowned automotive suppliers. Vossloh Kiepe serves as the system integrator with overall responsibility for the generator, supercaps, power electronics and energy management. The small 4 cylinder diesel engine is built by Cummins, and for the hybrid versions of the Citea a clear choice has been made for an optimal driveline with low emissions (standard EEV emission level), a low specific fuel consumption and the lowest possible weight. The rear axle, from ZF, includes two hub motors, which are integrated into the axle. The combination of these components has led to a perfectly integrated system that has no negative effects on the interior of the bus. In addition, the added weight has been kept to an absolute minimum. The various hybrid versions and the choice with regard to the number of supercaps make it possible for the transport operator to configure the optimal vehicle for the specific intended use.
Overall length: | 12.000 mm | Width: | 2.550 mm | Height: | 3.300 mm inkl. Klima | Engine: | Cummins ISB4.5EV 207 EEV | Number of cylinders: | 4 in Reihe | Power: | 152 kW (207 PS) | swept volume: | 4.500 cm³ | | Vossloh Kiepe hybrid system with water cooled synchronous generator (200 kW) and SuperCap modules | Drive axle: | ZF electronic portal axle AVE 130 • 2x 60 kW continuous power • 2x 80 kW peak power, 2x 465 Nm • Induction motor, 400 V, 11,000 tpm | | •Diesel engine operation at power or compressed air requirement • Up to 600 m electric driving possible | | 29 + 2 + 1 | | 51 | | ca. 12.250 kg | Total weight: | 18.000 kg |
Photos and text:
VDL Bus & Coach bv |