Proton unveils prototype Hybrid Car Developed In Collaboration With Lotus
By Mike Hanlon
April 15, 2007
April 16, 2007 Malaysia’s National auto manufacturer Proton has unveiled its first Hybrid prototype, designed in collaboration with Lotus Engineering. It is just over two decades since the company bolted together its first cars from Mitsubishi parts imported from Japan, but as the company has grown in strength, it has acquired considerable engineering design, development and manufacturing expertise, pulling off a major coup with its acquisition of Lotus in 1996. The 'EVE Hybrid' (Efficient, Viable, Environmental) research and development project was a collaboration of Proton and Lotus and EVE sports some impressive vital statistics. EVE has a 1.6litre petrol engine, which uses a 'micro-hybrid' start-stop system, a full parallel hybrid drive and a continuously variable transmission to achieve fuel economy of 5.6 litres/100km. maximum torque of whopping 233Nm at 1500rpm and maximum power of 105kW at 5500rpm enabling the car to accelerate from 0-100km/h in 9.0 seconds with a top speed of 188.8 km/h.
Extensive performance and drive cycle modeling of the prototype hybrid variant using the EVE Hybrid technologies indicate impressive performance figures.
Using the full parallel hybrid configuration the car can achieve fuel economy of 5.6 litres/100km (a 28 percent improvement over a standard petrol Proton GEN.2) while producing maximum torque of 233Nm at1500rpm and maximum power of 105kW at 5500rpm enabling the car to accelerate from 0-100km/h in 9.0 seconds with a top speed of 188.8 km/h and a CO2 emission level of just 134g/km, a 22 percent reduction compared with the standard car.
Proton has not revealed any details of when or if the prototype EVE Hybrid will be mass-produced.
The system showcases how OEMs can introduce lower emissions variants to existing model ranges that currently only offer conventional gasoline and diesel powertrains.
Lotus Engineering believes the application of hybrid technology is a key route for CO2 emissions reduction and that in the short term it will remain more viable to integrate hybrid technologies into existing model ranges than to develop expensive new dedicated hybrid platforms.
The EVE system will provide Proton solutions that will keep price premiums for hybrid variants to a minimum, thanks to lower development costs.
This new hybrid system is available immediately for introduction within current and next generation model lifecycles.
The EVE Hybrid program is focused on establishing the processes for integrating hybrid technology with minimal development time and cost, overcoming many of the challenges associated with integrating hybrid technology into existing platforms through intelligent, compact and discreet packaging of the necessary hybrid components.
Ultimately the EVE system is aimed at providing strong, viable business case propositions for offering a hybrid variant on a medium-high volume production car.
The research and development program was undertaken by a cross-functional team of Proton and Lotus engineers working together at Proton's base at Shah Alam near Kuala Lumpur in Malaysia and at Lotus Engineering's Hethel Headquarters in the UK.
The resulting EVE Hybrid Prototype was based on a Proton GEN.2 with a 1.6litre petrol engine, showcasing a trio of production-representative technologies including:
- a 'micro-hybrid' start-stop system - a full parallel hybrid drive - a continuously variable transmission
Compared to the baseline Proton GEN.2, tailpipe emissions are reduced from a competitive 172g/km to just 134g/km, a reduction of 22 percent, while fuel economy improves 28 percent from 7.2litres/100km to 5.6 litres/100km.
According to Mike Kimberley, Chief Executive Officer of Group Lotus, the technologies and know-how showcased in the EVE Hybrid are the latest addition to the Proton family of companies suite of efficient performance solutions for the automotive industry.
"As an automotive consultancy and global OEM, we are able to manage all elements of a hybrid integration project, with extensive drivetrain, vehicle, electrical and control systems expertise from design and development through to production," said Mr. Kimberley.
This project is an example of how the Proton / Lotus family can successfully deliver exceptional projects and products and the EVE Hybrid technology further reinforces the Group's position as creative technology leaders in 'green' automotive engineering.
The addition of the EVE Hybrid solutions to Lotus Engineering's extensive capabilities, together with the experience of developing Bio Ethanol flex-fuel Lotus Exige 265E means that the group is an ideally placed high technology organisation suited to helping the global industry to find a solution for future low emission personal transport needs.
A number of the technologies featured in the EVE Hybrid are production-ready, employing systems deliberately sourced from established tier one suppliers in order to demonstrate the availability of components, the minimisation of development costs and to maximise business case viability.
The EVE 'Micro-hybrid' stop-start system has been integrated through a starter-alternator system that switches the engine off when the vehicle stops, at traffic lights or stop signs during town driving for example. The engine restarts automatically when the brake pedal is released.
As a result, noise, emissions and fuel consumption are reduced. The unit runs on the standard vehicle 12-volt electrical system and combines both starter motor and alternator function.
The EVE features a full parallel hybrid technology system including a specially designed 30kW, 144V motor packaged in the bell housing between the engine and transmission. It delivers electric drive or regenerative braking via an additional clutch linking the motor to the drivetrain.
The motor provides the same start-stop functionality as the micro-hybrid with the additional benefit of electrical drive or drive assist, either boosting the drivetrain performance or providing economy and emissions benefits by operating as an electric vehicle.
The EVE's CVT (Continuously Variable Transmission) allows the ratio between the input and output shaft to be varied continuously depending on load within a given range, providing an infinite number of possible ratios.
The integration of a CVT gives benefits in fuel consumption and emissions control. In addition, its compact package assisted in the application of a hybrid electric drive and it provides smooth acceleration and low transmission noise.
Various changes have been made to the Proton 1597cc CamPro petrol engine to accommodate the EVE Hybrid system. The main modification was the redesign of the front end accessory drive to accommodate a Valeo 'StARS' starter/alternator, which drives the micro hybrid start-stop system.
The redesigned accessory drive also accommodates a Sanden hybrid Heating Ventilation and Air Conditioning (HVAC) compressor that operates by conventional belt drive and has an additional electrically driven capability which enables continued air conditioning operation when the engine is stopped.
The traditional belt driven power steering and water pumps have been replace with electric units to enable the investigation the economy benefits they can provide.
The specially manufactured electric motor and power electronics were developed in conjunction with specialist suppliers ElektroMagnetix and Turbopower Systems to meet the tight packaging constraints and to minimise any loss in overall vehicle performance.
The motor/generator and power electronics are water-cooled and include an auxiliary power unit to support the vehicle's 12volt systems.
An additional AP Racing clutch is packaged inside the motor and connects the IC engine to the traction motor allowing the engine to be switched off for electric drive only use.
A Punch Continuously Variable Transmission (CVT) has replaced the conventional transmission and a modified bell housing accommodates the electric traction motor.
The EVE Hybrid uses a Cobasys Series 1000, NiMH, 30kW 144V module that incorporates an integrated cooling system. This traction battery pack is securely mounted on the boot floor, displacing approx 47 litres of luggage space.
A sophisticated control system was developed to implement the energy management function by monitoring and controlling all sub-control systems including the engine management, motor/generator, transmission, HVAC, additional clutch, starter/alternator and battery pack.
To maintain the integrity of the braking circuit when the petrol engine is off, a Mes-Dea electric vacuum pump maintains the power assistance for the brakes.
A TRW electro-hydraulic power assisted steering pump has been fitted, allowing the retention of the existing steering column and hydraulic steering gear. This pump also provides hydraulic pressure for the additional clutch that engages the hybrid motor.
The instrument panel incorporates an additional LCD display developed by Lotus Engineering to show battery charge, power split between engine and motor, fuel economy and charge/discharge rate, and incorporates associated warning indicators where appropriate.
The dash is also fitted with new switches to select the car's operating mode - micro hybrid, full hybrid or full electric vehicle.