Overview
The Plus-Moby project is focused to the implementation of low cost and low energy intensity technologies to manufacture premium four wheel fully electrical micro vehicles (450-650kg and speeds up to 90+ km/h)) that can be upgraded to M1 configurations.
- Technologies and methodologies developed in previous calls of the EU Green Car will be implemented in terms of low aero-drag and safe structural designs, system integration on powertrain, batteries, solar panels, energy management (Wide-Mob and P-MOB), design criteria to reduce electromagnetic emissions (EM-safety), customer demand (Capire, ICT4FEV).
- Weight is optimised to satisfy maximum stability in all weather conditions including high lateral wind.
- Materials and systems are selected to assure the highest EURONCAP standards applied in conventional cars for both front and lateral crashes. Safety cells concepts will be introduced with low cost structures based on the combination of pure retainable and self-adaptable mechanics.
- Starting from a prototype having an energy consumption already demonstrated at 65Wh/km in the NEDC cycle, further reduction of energy consume is expected by enhancing the performance under pure electrical braking.
- Altogether the average energy consume is expected to be lower than 40Wh/km in the NEDC cycle with most of the days fully run by solar radiation only in most southern EU countries.
- The two-motor electric powertrain addressed, which has been demonstrated to have the highest fail safe mode, within Plus-Moby it will be demonstrated to emulate, and for certain extent replace, both the ABS and ESP expensive systems.
- The technology addressed will be implemented with low cost and easy to access manufacturing technologies.
- A relevant role is given to SMEs and regional SMEs clusters to assure competing speed and commitment.
- The partnership is organised in such a way that a new era of easy to produce low cost but high-performance micro e-vehicles is opened across all EU countries.
Funding
Results
Periodic Report Summary 1 - PLUS-MOBY (Premium Low weight Urban Sustainable e-MOBilitY)
The main achievements of the first period are the definition of the architecture and the definition of the related criteria which led the partners to specific choices on: lower and upper chassis, powertrain configuration(s), axle frames...
Project Context and Objectives:
The main achievements of the first period are the definition of the architecture and the definition of the related criteria which led the partners to specific choices on: lower and upper chassis, powertrain configuration(s), axle frames, materials, vehicle configurations and approach to manufacturing.
In particular the solution adopted for the lower and the upper parts of the chassis, starting from the lower and the upper parts of the WIDE-MOB chassis that were made on mild steel, have evolved in the PLUS-MOBY project The weight of the complete chassis (including the bench seat) has been reduced from 189kg (WIDE-MOB) to 126kg rev 3 by a combination of high strength and ultra-high strength steels HSS and UHSS. Aluminium parts are used in the suspension system while magnesium sheets are adopted as enclosures of the rear compartment. Plastometal bumpers are adopted as alternative to the conventional combination of an injection moulded bumper and a metal crash crossbar.
It is assumed, that the main technology of assembly the chassis is welding while the use of glues-bonding in combination with welding is foreseen to join the metal sheets to the tubular parts to seal-off the vehicle compartment from water and humidity.
Bonding and welding techniques have been analysed in detail while the use of screw is limited to body panels.
FEM simulations have been used to support the design of the chassis. The most classical chassis architectures have been compared with the tubular HSS and SHSS architecture chosen in PLUS-MOBY.
The design of the chassis is strictly correlated to the design of the suspension system, described in detail with simulations of its behaviour under load.
The materials used in the chassis and in the suspension system have been chosen in terms of the overall assembly process, upfront investments and production costs
Project Results:
The following advancements have been reached:
• ICPE designed, modelled, simulated and developed a synchronous reluctance motor (PMaSyR) assisted by ferrite permanent magnets of 7.5 kW rated power, 94% efficiency over the NEDC cycle, diameter 200mm, length 249mm. The motor has been characterized in the test bench and its integration in the axle system has been successfully demonstrated by dynamic tests at Bitron.
• Bitron developed algorithms to control the electric motor and implemented them in the microcontroller of the DC/AC three-phase inverter: the inverter with its microcontroller unit are commonly referred as “motor drive”.
o Real-time computation of the requested torque is demanded to a dedicated electronic control unit, commonly referred as VMU (Vehicle Management Unit), separated from the motor drive, which is also controlling gearbox shifting and the two drive trains together. Note: a solution per which the inverter also acts as VMU has been studied and implemented by IFEVS.
o The implemented algorithms allow real-time computation of the phase voltages to be applied to the electric motor in order to deliver the requested torque, according to maximum rating of the drive and the motor.
• A thermal model of the electric drivetrain within the Four-Wheel-Drive Fully Electric Vehicle has been developed by simulations has been developed by Surrey
The work has been supported by the definition of road tests and on-the-road measurements specification elaborated by IMBIGS, to be performed for the qualification of the PLUS-MOBY vehicle.
In view of the industrialization of the vehicle criteria have been adopted to simplify the production steps as well as the maintenance of the vehicle. The experience gained during the FP7 project WIDE-MOB have been taken as starting point toward a low-cost production of PLUS-MOBY vehicles.
Particular emphasis has been given by Polimodel-IFEVS-Magnetto to the design and development of the templates to assemble the full chassis and the axle system: their introduction for a semi-automated operated line based on manual welding is underway as a PLUS-MOBY output.
The designs made by IFEVS have been supported by FEM simulations performed by CIDAUT-IMBIGS aiming at assessing the structure of the vehicle and the related absorption elements.
A novel plasto-metal bumper structure has been characterized and simulated in detail. The most important variables like: material parameters, bumper’s structures, shapes and impact conditions have been analysed in order to improve the crashworthiness during collision. The metal-plastic bumper structure consists of steel, low-density polyethylene (LLDPE) and polyurethane (PUR) elements combined together. These structures were investigated by static load and impact modelling to determine the kinetic energy, potential energy and strain energy conversion. The results showed the stress (von Misses) and displacement graphs of the bumper assessing the safety of the structure. The simulations of the behaviour at 15km/h (assurance test) have led to a new design of the bumper arms so that they could allow a higher elastic behaviour thus absorbing all collision energy at low speeds.
Potential Impact:
For the first time in the history of mobility the technological advances of the overall system blocks within an electrical power train have reached the level for full electrical mobility to be possible in efficiency. It is generally recognised that electrical mobility is the route to save the primary energy consumption in transportation. The overall systems integration, that is, overall system optimization, plays a crucial role in that power and energy storage systems should preferably be coupled with advanced local management, drive electronics be coupled with drive motors embedding torque control while a central unit manages power and energy flows within the electric drive train.
The vehicle can be plugged – in to the grid to either buying or selling electricity, the vehicle can use renewable electricity, but within PLUS-MOBY we do something more, most of the electricity is produced on-board of the vehicle and in countries having an irradiation like in south Europe, a low cost in-the-body photovoltaic will be demonstrated to provide free clean energy for driving up to 30km a day.
PLUS-MOBY addresses efficiency by adopting distributed propulsion (two motors for an effective four-wheel drive), low weight
In summary per a defined range the overall energy saving resulting from the PLUS-MOBY activities allows to attack the most critical aspect for a wide market acceptance of the EVs that is the price of the accumulator pack (currently in the range 300-350€/kWh). Using the available Li-P Technology (190Wh/kg) with 70kg of accumulators, PLUS-MOBY vehicles assure a range of 175km. Limiting the vehicle to typical urban uses only, the battery pack can be limited to 40kg and less when taking into consideration the impact of the embedded solar panels. PLUS-MOBY addresses the target per which in south Europe most travels up to 30 km/day will be covered the on-board solar cells. The vision implemented in PLUS-MOBY, per which micro EVs are game changers, will stimulate Members States to be all involved in the manufacturing of new forms of clean and sustainable mobility.
List of Websites:
www.moby-ev.eu