Hyundai has announced a new six-speed automatic transmission for hybrid electric vehicles (HEV) at the company’s annual International Powertrain Conference held yesterday in Namyang, South Korea.
The company explained the new six-speed automatic transmission integrates the electric motor and applies a number of technologies that deliver tangible benefits to the customer. The new unit will be fitted to future Hyundai hybrids, including the upcoming all-new Sonata hybrid.
In this set-up, almost all the hybrid powertrain components are integrated in the transmission; this minimizes energy losses and increases fuel economy according to Hyundai. A new traction motor and electric oil pump (EOP) have been installed, while the torque converter has been removed completely. A lighter torsion damper, and new engine clutch, which features fewer clutch discs, are said to reduce drag and contribute to a more efficient transfer and use of power.
Hyundai added the most significant change is within the oil pump system. The new transmission with the new oil pump system is said to achieve improved fuel efficiency, by removing the mechanical oil pump (MOP) causing hydraulic losses and by applying a new electric oil pump (EOP) which automatically optimizes the system according to all driving conditions.
A side benefit of this set-up, per Hyundai, is that with fewer components, the new transmission weighs 130 kilograms (wet), making it lighter than its previous version.
Combined to a 1.0-liter engine
First displayed at the 2014 Paris Motor Show, the new Kappa 1.0-liter T-GDI is described by Hyundai as a high performance downsizing engine which could replace larger displacement natural-aspirated engines offering high fuel efficiency and low CO2 emission.
The 998cc three-cylinder unit is based on the established Kappa 1.0-litre MPI engine and includes direct gasoline injection and a small, single-scroll turbocharger.
The 1.0-liter T-GDI is expected to be part of the company’s worldwide engine line-up in 2015.
According to Hyundai, the new engine comes with an electronically-controlled wastegate to improve low-end torque and transient response with better fuel economy by reducing pumping friction. The unit features a six-hole laser-drilled GDI injector, high pressure fuel supply system of up to 200 bar, in order to optimize clean combustion, fuel economy and emissions to meet Euro6 emission standards.
Another novel technology used is, per Hyundai, a split-cooling concept designed to manage different temperatures in the cylinder head and block area. The cylinder block is heated up quickly for lower friction and more efficient run, while the cylinder head operates at moderately low temperatures to suppress knock tendency and thus improve fuel economy. The exhaust manifold is integrated within the cylinder head which efficiently cool down the exhaust gas temperature using the cylinder head water jacket around the exhaust port.
Hyundai says these efforts result in faster warm-up reducing real-world fuel consumption and emissions.