Auris hybrid 2010 petrol, diesel, full hybrid:hybrid synergy drive® a unique eco driving experience

—Full hybrid, series-parallel system architecture — the first and only full hybrid powertrain in the C-segment

—1.8 litre VVT-i Atkinson cycle petrol engine and 60 kW electric motor for maximum system power of 136 DIN hp

—0-100 km/h in 11.4 seconds, top speed 180 km/h - performance to match any conventional 2.0 litre diesel or petrol hatchback

—Combined cycle fuel economy of 3.8 l/100 km - the fuel consumption levels of a small city car

—Highly tax-efficient CO2 emissions - from just 89 g/km

—Four driving modes, including EV, ECO and POWER 'on demand' modes

—Smooth, sophisticated driving experience with class-leading NVH levelsThe Auris HSD drives like no other car in its class. It is equipped with the first and only full hybrid powertrain in the C-segment. Its introduction will create an important shift in customer perceptions of full hybrid technology.

The advantages of exceptional fuel efficiency and low CO2 emissions are obvious. However, the Auris HSD customer will also experience a smooth and sophisticated, relaxed and stress-free driving experience thanks to the everyday usability, driving comfort and remarkable quietness of Toyota's multiple award-winning powertrain.

Named International Engine of the Year in 2004, Green Engine of the Year and Best Fuel Economy Engine of the Year for the fifth consecutive year in 2008, Toyota's Hybrid Synergy Drive® represents the ultimate synergy of high technology and environmentally-conscientious forward thinking in powertrain design.

The Unrivalled Efficiency Of Toyota's Full Hybrid Technology

Unlike rival, mild hybrid vehicles, the new Auris HSD is a full hybrid capable of operating in petrol and electric modes alone, as well as a combination of both. Its advanced Hybrid Synergy Drive® system delivers the energy-saving benefits of a series hybrid combined with the performance benefits of a parallel hybrid.

Full hybrid technology equips the new Toyota hatchback with instant power, impressive, seamless acceleration and remarkably quiet operation, yet returns class-leading fuel efficiency and the lowest possible emissions.

In combination, the Hybrid Synergy Drive® system's 1.8 litre VVT-i petrol engine and electric motor generate a maximum power output of 136 DIN hp, equipping the Auris HSD with a 0-100 km/h acceleration time of 11.4 seconds and a maximum speed of 180 km/h — performance to match any conventional 2.0 litre diesel or petrol hatchback.

Conversely, the Auris full hybrid returns fuel consumption figures of only 3.8 l/100 km in the European homologation combined cycle and targets remarkably low, highly tax-efficient CO2 emissions of just 89 g/km. In addition, the Auris HSD generates significantly lower NOX and PM emissions than diesel engined cars of comparable performance.

Moreover, when operating in a unique, switchable EV mode, the Auris HSD offers zero CO2, NOX and PM emissions, driving for up to about two kilometres at speeds of up to about 50 km/h, dependant on battery charge and driving conditions.

Hybrid Synergy Drive® system architecture

The Auris HSD's latest generation series/parallel full hybrid system features a 1.8 litre VVT-i petrol engine, a powerful electric motor, a generator, a high performance battery, a power control unit and a power split device which employs a planetary gear set to combine and re-allocate power from the engine, electric motor and generator according to operational requirements.

Key to the successful installation of Hybrid Synergy Drive® within the Auris HSD's front-engined hatchback platform, the electric motor, generator and power split device are all housed in one lightweight, highly compact transmission casing directly comparable in size to that of a conventional gearbox.

The full hybrid drive system's seamless, E-CVT electric continuously variable transmission is controlled by Shift-by-Wire technology, using an electric shift lever system.

Powered by the hybrid battery, the electric motor works in tandem with the petrol engine to boost acceleration during normal driving. Unique to Toyota's full hybrid drive technology, the electric motor alone powers the driven wheels when the Auris HSD is operating in EV mode.

During deceleration and under braking, the electric motor acts as a high-output generator to effect regenerative braking. Normally wasted as heat, kinetic energy is recovered as electrical energy for storage in the high performance battery.

1.8 Litre Atkinson Cycle Engine

The lightweight, highly compact, 4-cylinder 1798 cc Atkinson cycle petrol engine develops max output of 73 kw/99 DIN hp at 5200 rpm and max torque of 142 Nm at 4000 rpm.

Combined with a cooling Exhaust Gas Recirculation system, the adoption of the Atkinson cycle offers significant gains in fuel efficiency and the reduction of emissions.

Because the intake valves close late in an Atkinson Cycle engine, compression is delayed. This creates a high expansion ratio for less compression, reducing intake and exhaust energy losses and converting combustion energy to engine power more effectively. As a result, the exhaust temperature is lower than that of conventional engines. The cooling Exhaust Gas Recirculation system reduces cooling loss and pumping loss and consequently fuel efficiency is enhanced. Heat tolerant catalyst adoption is mostly contributing to reduction of enrichment.

The 1.8 litre engine features numerous further enhancements to both improve performance and help minimise fuel consumption and emissions. VVT-i (Variable Valve Timing-intelligent) helps boost response levels across the entire rev range by varying the air-fuel intake and exhaust valve timing to suit the conditions at any given time. As well as improving torque at low and medium engine speeds, the system also reduces emissions and enhances fuel efficiency.

In addition, the engine features roller rocker arm valve-train control, a resin intake manifold with an optimised port configuration and 12-hole, atomising, long nozzle injectors. Thin, long reach spark plugs contribute to enhanced anti-knocking performance, and low tension piston rings, reduced piston friction, a standing oil jet for piston cooling and a stainless steel pipe exhaust manifold further enhance engine efficiency. In combination, these advanced technologies contribute to improved power output with reductions in both fuel consumption and emissions.

Ultra-low Noise, Vibration and Harshness (NVH) characteristics are one of the key attributes of Hybrid Synergy Drive® and particular attention has been paid to minimising engine noise and vibration. The rigidity of engine parts including the cylinder block and crank case has been optimised through in-depth Computer Aided Engineering (CAE) analysis. A highly rigid, ribbed aluminium cylinder head cover combines light weight with reduced noise and vibration.

The engine itself is mounted on a 4-point mounting system with mounting rubber characteristics optimised for the suppression of noise and vibration. And dynamic damper is integrated within the engine mount to further minimise noise and vibration, as well as reducing engine start/stop shock.

Hybrid Transaxle with Electric Continuously Variable Transmission (E-CVT)

Housing the electric motor, generator, power split device and a reduction gear in one lightweight, highly compact transmission casing directly comparable in size to that of a conventional gearbox, the transaxle lies at the heart of the Hybrid Synergy Drive® system.

The full hybrid drive system's seamless, E-CVT electric continuously variable transmission is controlled by Shift-by-Wire technology, using an electric shift lever system. The shift lever itself is designed to always return to its 'home' position when released and the shift position can be checked on the shift position indicator integrated within the driver's instrument cluster.

Adjacent to the shift lever, a parking switch with integral indicator light is used to engage or release a parking lock mechanism within the transmission gearing. The parking lock is automatically deactivated when driving off and automatically re-engages when the car is switched off.

The transaxle features a multi-function gear train making it lightweight and highly compact. Numerous measures have been adopted to reduce component noise and drive shaft energy losses, lowering hybrid system fuel consumption. The world's first internal tooth shaving process offers enhanced planetary ring gear precision, minimising transmission noise. The lubrication system has been designed to reduce stirring and the use of ball bearings minimises transaxle component friction.

Electric Motor/Generator

The high performance, permanent magnet, synchronous electric motor/generator has a maximum power output of 60 kW. It works in tandem with the petrol engine to boost acceleration and power the driven wheels alone when the Auris HSD is operating in EV mode.

Generating instant power and a maximum 207 Nm of torque the motor is six times more powerful than that of rival, mild hybrid systems. It is air cooled and maximum drive voltage amplification is 650 Vdc. However, under ordinary driving conditions, unless maximum output is required, the motor is driven at an unamplified voltage whenever possible to enhance fuel efficiency.

High Output Battery

The battery pack uses proven and reliable nickel-metal hydride technology. It is located beneath the rear loadspace floor, minimising impact on cabin accommodation and giving the Auris HSD a luggage capacity of 279 litres.

Power Control Unit

Similar in size to a 12 volt battery, the Hybrid Synergy Drive® power control unit (PCU) consists of a voltage boost converter, an inverter and a DC/DC converter, controlled by a motor control ECU which receives commands from the hybrid vehicle control ECU.

The inverter converts the battery's direct current into a 650 volt alternating current to drive the electric motor and occasionally, the generator, offering significantly improved PCU performance.

A conventional, non-hybrid vehicle is equipped with an alternator to charge the auxiliary battery. However, because an alternator cannot operate during engine cut-off driving mode, a full hybrid vehicle requires an alternative system. Hybrid Synergy Drive® incorporates a DC/DC converter to reduce the high voltage of the 202 V system battery pack to 14 V, supplying power to the accessory systems and charging the auxiliary battery.

Hybrid Synergy Drive® In Operation

Over the course of any journey, Toyota's Hybrid Synergy Drive® system operates in several different modes to maximise the Auris HSD's overall efficiency.

At rest, the engine stops automatically to conserve fuel. Under operating conditions of low engine efficiency such as start up and low to mid-range speeds, the vehicle automatically runs in EV mode, on the electric motor alone, thus eliminating CO2, NOX and PM emissions.

Under normal driving conditions, power allocation is constantly adjusted between engine and electric motor to combine optimum performance with maximum fuel efficiency.

Via an Electronically Controlled Braking System, the electric motor acts as high-output generator during deceleration and under braking to effect regenerative braking, optimising energy management in the Hybrid Synergy Drive® system by recovering kinetic energy (normally wasted as heat under braking and deceleration) as electrical energy for storage in the high performance battery.

Battery power level is constantly managed via an engine driven generator to obviate any requirement to recharge the system from an external source.

Three on-demand Driving Modes - A Unique Eco Driving Experience

Supplementing the NORMAL drive mode, three alternative, 'on-demand' drive modes — EV, ECO and POWER - may be selected to further increase driving efficiency, performance and fuel economy.

From start up and at speeds of less than 50 km/h with the NORMAL drive mode selected, the new Auris HSD automatically operates in EV mode depending on driving conditions and battery charge, driving under electric motor power alone to give instant power and an extraordinarily smooth, quiet ride with minimal NVH. This unique driving mode is not available to drivers of mild hybrid vehicles, requiring the full hybrid technology of Hybrid Synergy Drive®.

Though the petrol engine will still start if the system judges that its output is necessary, the switchable EV mode allows for significantly greater throttle inputs without engine start up. Hence, with vehicle range dictated by battery charge, the EV drive mode allows for urban driving with minimal noise and zero CO2, NOX and PM emissions for up to two kilometres. Because the use of only light to medium throttle inputs keeps the petrol engine switched off throughout its operation, the EV drive mode contributes to a significant reduction in the new Auris HSD's overall fuel consumption.

In ECO mode, throttle response to aggressive accelerator pedal inputs is reduced and air-conditioning control optimized for improved fuel economy.

A POWER mode also modifies the response of the Auris HSD to throttle inputs, here boosting power to improve acceleration and enhance driving pleasure. The POWER mode provides a 25% higher throttle response to accelerator pedal input.

Complimenting these three on-demand drive modes, an Eco Drive Monitor helps drivers maximise the fuel efficiency of Toyota's full hybrid powertrain. Via the multi-information indicator in the instrument cluster, drivers may monitor the flow of energy within the Hybrid Synergy Drive® system for each driving mode. This helps them develop relaxed, fuel efficient driving techniques and maximise system efficiency.

In addition, a simple yet clear power consumption gauge in the combination meter shows how much power is being used or generated at any given time.

Comfortable, Ultra-Quiet Driving with low NVH level

The Auris HSD brings the extraordinarily refined, smooth and silent Hybrid Synergy Drive® experience to European C-segment customers for the first time.

In order to maximise the unique benefits of Toyota's full hybrid drive system, the Auris HSD features numerous body, chassis, suspension and steering modifications to the recently launched Auris 2010 model range.

HSD Adapted Bodyshell

The centre floor body of the Auris HSD has been redesigned to accommodate the Hybrid Synergy Drive® battery pack, which is located beneath the rear loadspace floor. Minimising impact on cabin accommodation, this gives the new Toyota full hybrid a luggage capacity of 279 litres.

Tuned Suspension

Through collaboration between the Japanese R & D suspension design team and Toyota's European R & D conformity testing team, the Auris HSD's ride and handling has been fine-tuned specifically for the customers and roads of the European market. It combines stable high speed driving performance with secure handling and superior ride comfort.

The front suspension features a variation of the highly effective MacPherson strut, known as an L-arm MacPherson strut. This compact and highly rigid design brings the strut in-board from the wheel hub, which allows for a wider track with superior stability and excellent noise and vibration suppression.

The rear suspension benefits from a highly efficient torsion beam system featuring a separate spring and damper layout, creating a super-compact design which does not intrude into the vehicle's loadspace.

Compensating for a change in weight distribution effected by the installation of the hybrid battery pack to the rear, both the Auris HSD's front and rear dampers have been tuned for optimum ride quality.

Lowered Chassis with Bespoke Wheels and Tyres

In conjunction with numerous aerodynamic bodywork details designed to maximise the fuel efficiency of the full hybrid drive system and minimise wind noise during high speed cruising, the Auris HSD's ride height has been lowered by 5 mm to further enhance aerodynamic efficiency and high speed stability.

In addition, it has been equipped with unique, 15" or 17" Prius-style aero wheels with enlarged air gaps for improved cooling air flow to the Electronically Controlled Braking System and 195/65R 15 or 215/45R 17 low rolling resistance tyres (latest generation).

Electronically Controlled Braking System

The Auris HSD's full hybrid drive system incorporates an Electronically Controlled Braking System which coordinates the control of both hydraulic and regenerative braking and is 18% lighter and 31% smaller than conventional systems.

The system is equipped with ventilated disc brakes to the front -273 mm for 15" wheels and 296 mm for 17" wheels- and 259 mm solid discs to the rear for optimum braking efficiency. Coordinated control of the hydraulic and regenerative braking systems maximises the regeneration of energy by the electric motor during deceleration and under braking.

Revised Electric Power Steering (EPS)

With a quick ratio of 14.44:1 and just 2.9 turns lock-to-lock, the Auris HSD's speed-sensitive Electric Power Steering (EPS) reduces hybrid system energy consumption for improved fuel economy.

The EPS' compact, high output motor and torque sensor are built into the steering column, optimising steering assistance for more precise control of the vehicle. EPS improves fuel economy by consuming power only when steering force assistance is needed. It is highly durable and requires no hydraulic fluid.

Compensating for the change in weight distribution effected by the installation of the hybrid battery pack to the rear, as well as the re-tuned suspension, the Auris HSD's EPS has also been revised to maintain optimum feedback and vehicle agility.

Low Noise, Vibration and Harshness (NVH)

Reinforcing the extensive Noise, Vibration and Harshness (NVH) suppression measures inherent in the Auris HSD's aerodynamic styling and ultra-quiet Hybrid Synergy Drive® system, particular attention has been paid to noise and vibration reduction within its highly rigid, impact absorbing body structure.

The engine is mounted on a 4-point system incorporating dynamic damper for maximum suppression of noise and vibration as well as reduced engine start/stop shock.

Road and engine noise have been rigorously suppressed through the comprehensive use of high-performance sound proofing materials throughout the engine and passenger compartments. An acoustic windscreen design further reduces wind noise for improved quietness at cruising speeds.

As a result, the new Toyota full hybrid sets the highest standards in Noise, Vibration and Harshness (NVH) reduction, sound absorption and vibration damping. This ensures customers enjoy a cabin environment of unequalled calm and quietness at all vehicle speeds.