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Today, electric powered vehicles are in the focus of politics and the economy. They are very practicable and useful for limited ranges (about 100km) but for various reasons, such as battery aging, demand for heating, traffic jams etc., this already decreased driving range is not always attainable. In such cases, electrical energy can be generated with a more or less large combustion engine, a so called range extender. Such parallel and serial range extender systems are being tested at the moment. In the following paper, the advantages and disadvantages from small range extender systems (“coming home”-systems) and also concepts without restrictions (two electric motors; e.g. Toyota Prius, VW twin drive etc.) will be discussed and the CEA concept for a Mega City Electric Vehicle, developed by IVD, will be presented. This concept is based on a vehicle from the A-C segment with pure electric propulsion, which is supported by an internal combustion engine at higher speeds.

“Zero Emission Vehicles” in the form of pure electric vehicles are quite feasible and useful for limited cruising ranges. However, market success depends on customer acceptance. Studies show, that customers expect electric vehicles with driving performance similar to conventional vehicles while comparable cruising ranges should be available at low additional cost. With currently available batteries using lithium ion technology a gravimetric energy density of only one percent of the energy density of gasoline or diesel can be reached. With respect to acceptable additional costs this effect leads to significant reduction of the cruising range. For various reasons such as battery aging, demand for heating, traffic jams, etc., this already decreased cruising range is further reduced. In such cases electrical energy can be generated with a demand oriented (down-) sized combustion engine, a so called “Range Extender”.

According to the ISO 16183 [1] protocol for heavy-duty diesel engines, particulate matter can be determined using a partial flow dilution system (PFDS). In order to control a PFDS, it is necessary to know the exact exhaust gas mass flow rate at the sample probe of the system at any given time. For the purpose of operating a PFDS with online control, a transformation time for the entire system (exhaust mass flow determination and partial flow adjustment) of equal or less than 300 ms is specified. In order to minimize the dynamic requirements for the PFDS a fast determination of the exhaust flow rate is necessary, which can be achieved most easily by using the intake flows (air + fuel flow) into the engine. This paper reports on the development and testing of an intake flow based model for calculating real time exhaust flow rate that accounts for the influence of the filling and emptying of the manifolds of a turbocharged diesel engine during dynamic operation.

This paper reports on the development and testing of a compact and mobile CVS system for the measurement of particulate matter emissions of diesel passenger cars. It consists of the same components as a conventional CVS system but needs much less space. Reducing the size of the CVS system was achieved by the optimization of the turbulent flow in the dilution tunnel by the use of an optimized mixing chamber, in which the engine exhaust gas is diluted with filtered ambient air. The measures taken to improve the turbulence in the dilution tunnel lead to the same effect as a tunnel with dimensions according to the legislative regulations. All the components of the mobile CVS system are arranged in a very compact design, so that the new system has a size of only about (1.70 x 0.80 x 2.10) m. Due to the mobility which is possible with such a design, the new system can be quickly adapted to different engine and vehicle test cells for passenger cars.

The regeneration of a loaded particulate filter is one of the biggest challenges in the development of filter systems. The reason is under certain conditions the exhaust gas temperature does not reach the required minimum regeneration temperature for a longer period of time. This paper describes results achieved with a catalytically coated filter alone and in combination with engine parameters, which are used to increase the exhaust gas temperature. The activity of the catalytically coated filter was evaluated by using the well-known balance temperature test. The soot-burning rate was determined at different exhaust gas temperatures. The investigated engine control parameters included intake air throttling and a control of lambda. A special low-temperature transient test was designed to evaluate the regeneration efficiency of the catalytically coated filter and the described engine control parameters under more realistic conditions.

In the near future, technical demands for powerful electric motors integrated into the drive train can be fulfilled. These motors combine the functionality of starter and alternator offering a higher electric power than conventional alternators. At low engine speed, they can work as a motor and introduce an additional driving torque in the drive train (booster). The required introduction of suitable electrical storage devices enables regenerative braking to reduce fuel consumption significantly. In this paper, for homologation tests and customer use, the potential savings of regenerative braking are shown for a variety of engines, vehicles and test cycles.