Honda Motor Corporation has announced that it has developed a new hybrid system, with a three-stage i-VTEC engine that will be introduced in the new Civic Hybrid, to be launched in 2006.

Honda Motor Corporation has announced that it has developed a new hybrid system, with a three-stage i-VTEC engine that will be introduced in the new Civic Hybrid, to be launched in 2006.

With Honda's i-VTEC (intelligent Variable Valve Timing and Lift Electronic Control) system providing three stages of valve timing at low and high revolutions, and in cylinder idle mode, the engine has been made more compact and efficient than the one it replaces in the Civic IMA.

The new system uses intelligent engine functions and a more efficient Integrated Motor Assist system to achieve a 20 per cent increase in system output over the current system. The 1,8-litre's size has also been reduced by about five per cent, while fuel economy has improved and emissions have dropped, the manufacturer claims.

The three-stage i-VTEC engine uses three hydraulic pathways to engage and disengage five rocker arm assemblies, providing three stages of valve control depending on the driving conditions. When the cylinders are idle during deceleration, combustion in all four cylinders is stopped and they are sealed to reduce pumping losses and achieve a 10 per cent improvement in the recovery of braking energy compared with the current Civic IMA.

At start-up and acceleration, the engine operates in low-speed valve timing mode, with motor assist. With rapid acceleration, the engine switches to high-speed valve-timing mode, again using motor assist.

While cruising at low speeds, the valves of all four cylinders are closed and combustion is halted, allowing the electric motor to power the vehicle on its own. With deceleration, the cylinders are again closed and the motor recovers the maximum amount of energy released under braking, and stores it in the battery.

Aluminium die-cast pistons, ion-plated piston rings and "plateau honing" of the cylinder walls (for a smooth surface) are some of the adjustments made to reduce friction in the new engine.

The electric motor has coils with high-density windings and high-performance magnets for output one-and-a-half times more than that of the current model. The inverter used to control the motor speed is integrated with the car's ECU for digital control, which results in greater efficiency and fuel economy.

The battery output has also been increased by about 30 per cent, and has a more compact storage box with increased cooling capabilities and vibration resistance.

The regenerative braking system allows for maximum regeneration along with smooth deceleration to match the brake-pedal pressure.

The air conditioner has a hybrid compressor that is powered by both the engine and the motor. When the engine is in Idle Stop mode, or the temperature is stable, the compressor is powered by the motor. However, when rapid cooling is required, the engine and the motor combined powers the air conditioning system.

Original article from Car