Published November 13, 2012
By Philippe Crowe
Honda has improved both its hybrid system and its hybrid strategy, developing a lightweight and compact one-motor hybrid system for small vehicles.
Honda calls this system the SPORTS HYBRID Intelligent Dual Clutch Drive system.
This hybrid system is the latest addition to the Earth Dreams Technology series of Honda powertrain technology that aims to combine driving performance and good fuel economy.
Combined to the SPORT HYBRID Intelligent Multi Mode Drive for mid-sized vehicles and the SPORT HYBRID SH-AWD (SPORT HYBRID Super Handling - All Wheel Drive), the SPORT HYBRID Intelligent Dual Clutch Drive will allow Honda to offer a SPORT HYBRID system for any vehicle sizes and characteristics.
The new powertrain in the one-motor SPORT HYBRID Intelligent Dual Clutch Drive combines a newly developed inline 4-cylinder 1.5-liter Atkinson cycle engine with a 7-speed dual clutch transmission (DCT). According to Honda, its built-in high-output motor and lithium-ion battery improve efficiency by more than 30 percent compared to a conventional one-motor hybrid system.
Honda also said that the combination of the one-motor hybrid system and the engine offers sporty driving during acceleration and high-speed cruising by using the clutches to engage the engine. With this system, electric vehicle (EV) driving is utilized during start up and low- to medium-speed cruising by using the clutches to disengage the engine.
You can expect this system to appear in the next generation Fit.
Honda’s new hybrid strategy also relies on the two-motor SPORT HYBRID Intelligent Multi Mode Drive / Plug-in.
Honda says this is the world’s most efficient two-motor hybrid system optimized for mid-sized vehicles.
The adoption of high-efficiency /high-output motors offers quick acceleration with an EV-like driving feel and high fuel economy, but combining this to the flexibility of a hybrid.
Honda says this hybrid system achieves the world’s highest efficiency by combining a newly-developed engine dedicated for hybrid vehicles (the Earth Dreams Technology new 2.0-liter Atkinson cycle engine); an electric CVT coupled to two built-in motors and a lock-up clutch; a lithium-ion battery; and making it all work in sync through a smart system which can switch modes to match driving styles and situations.
The system switches the operation among three driving modes. “EV Drive” for driving powered only by the electric motor using electricity from the battery and regeneration during deceleration; “Engine Drive” for medium-to high-speed cruising with the engine and axle directly connected by a lock-up clutch and engine power being mechanically transferred to the wheels; and “Hybrid Drive” for urban driving and powerful acceleration using the electric motor with electricity generated by the engine.
This two-motor hybrid system, which is also suitable as a plug-in hybrid system, will be installed to the North American version of the Accord, scheduled to be introduced to the market in January 2013.
Third in Honda’s new strategy is the three-motor SPORT HYBRID SH-AWD (SPORT HYBRID Super Handling - All Wheel Drive).
According to Honda, this system combines a V6 engine to a high-output three-motor system allowing for acceleration equivalent to that of a V8 engine, but with fuel economy better than that of an inline 4-cylinder engine.
A new V6 3.5-liter direct-injection engine is installed in the front of the vehicle and is combined to a newly-developed 7-speed DCT system with a built-in motor. This Honda technology also uses two motors installed in the rear to control torque distribution to the right and left rear wheels.
Using independent motors for the right and left rear wheels, positive torque is applied to the outside wheel and negative torque is applied to the inside wheel, making independent control of torque distribution to the rear wheels possible without relying on engine output.
Interestingly, depending on the radius of the curve, the energy generated by the inside wheel is recovered electrically and applied to the outside wheel to self-generate torque necessary for the vehicle to make the turn.
Honda proudly stated these latest advancements in electric vehicle technologies further progress Honda towards making the Sport Hybrid, such as the forthcoming new NSX model, a reality.