Final Report Summary - EE-VERT (Energy efficient vehicles for road transport)
Road transport is the second largest producer of greenhouse gases within the European Union (EU). EE-VERT targets a 10-12 % reduction in fuel consumption and carbon dioxide (CO2) generation for conventional vehicles at an attractive cost-benefit ratio. The central EE-VERT concept is the electrification of auxiliary systems, operating them demand oriented and supplying their energy by CO2-neutral energy from energy sources such as extended recuperation of braking energy, waste heat recovery or solar cells, using an overall energy management strategy. To achieve improved efficiency and power the generator operates at 40 V and to connect the elements to the standard electrical system a new architecture has been devised that works with 40 V and 14 V levels.
The main components of the 40 V network are a new generator based on the claw pole technology with integrated permanent magnets, a Li-ion battery system and a direct current (DC) - DC converter with multiple inputs (MIPEC) for interfacing between the two voltage levels. The available generator power during recuperation is up to 11 kW. The efficiency of the new generator is above 80 % in the low range of speed while in the high range of speed the efficiency is still above 70 %. The MIPEC efficiency is around 94 %.
The generator, Li-ion battery and MIPEC were integrated into the high voltage network, firstly on a test bench and later in the demonstrator vehicle. Optimised and electrified actuators including a fuel pump and a vacuum pump together with a commercial electrical alternating current (AC) compressor and a solar panel were also fitted to the demonstrator vehicle. In addition, an electric actuator for the variable-turbine geometry (VTG) turbocharger was developed and successfully tested on an engine and new electric actuator designs suitable for .an AC compressor were evaluated on the test bench. The safety implications of introducing a dual-voltage architecture were also investigated.
A simulation software platform was developed, using Matlab / Simulink, which models the project reference car, an Alfa Romeo 159. This simulation model is based on specifically developed models for each of the new components mentioned and realistic models for the other elements in the vehicle.
The simulation work indicates that average fuel savings of 10 % for real life driving cycles and up to 20 % when the start and stop functionality is applied to real life urban cycles are possible and that real life urban driving cycles benefit the most from the EE-VERT concept. Fuel consumption results for the demonstrator car validated the simulation work, confirming that the EE-VERT concept can lead to fuel savings of 10-20 % depending on the mission cycle for a modest increase in costs.
The main components of the 40 V network are a new generator based on the claw pole technology with integrated permanent magnets, a Li-ion battery system and a direct current (DC) - DC converter with multiple inputs (MIPEC) for interfacing between the two voltage levels. The available generator power during recuperation is up to 11 kW. The efficiency of the new generator is above 80 % in the low range of speed while in the high range of speed the efficiency is still above 70 %. The MIPEC efficiency is around 94 %.
The generator, Li-ion battery and MIPEC were integrated into the high voltage network, firstly on a test bench and later in the demonstrator vehicle. Optimised and electrified actuators including a fuel pump and a vacuum pump together with a commercial electrical alternating current (AC) compressor and a solar panel were also fitted to the demonstrator vehicle. In addition, an electric actuator for the variable-turbine geometry (VTG) turbocharger was developed and successfully tested on an engine and new electric actuator designs suitable for .an AC compressor were evaluated on the test bench. The safety implications of introducing a dual-voltage architecture were also investigated.
A simulation software platform was developed, using Matlab / Simulink, which models the project reference car, an Alfa Romeo 159. This simulation model is based on specifically developed models for each of the new components mentioned and realistic models for the other elements in the vehicle.
The simulation work indicates that average fuel savings of 10 % for real life driving cycles and up to 20 % when the start and stop functionality is applied to real life urban cycles are possible and that real life urban driving cycles benefit the most from the EE-VERT concept. Fuel consumption results for the demonstrator car validated the simulation work, confirming that the EE-VERT concept can lead to fuel savings of 10-20 % depending on the mission cycle for a modest increase in costs.