South Korean multinational automotive manufacturer, Hyundai Motor Group, has developed the world’s first Continuously Variable Valve Duration (CVVD) technology. This new technology is production-ready and will soon be seen in Hyundai and Kia vehicles. The innovation was unveiled at the Hyundai Motorstudio in Goyang, alongside the Smartstream G1.6 T-GDi, which is the first engine to feature this next-gen technology. The CVVD technology not only optimizes engine performance and fuel efficiency but also reduces the level of harmful emissions when compared to the previous-generation engines. The valve control technology regulates the duration of valve opening and closing according to driving conditions, achieving a 4% boost in performance, a 5% improvement in fuel efficiency and a 12% decrease in vehicular emissions.
CVVD: Continuously Variable Valve Duration
Typical variable valve control technologies manage the timing of the valve’s opening and closing (as in Continuously Variable Valve Timing – CVVT) or control the volume of air allowed by adjusting the depth of the opening (Continuously Variable Valve Lift – CVVL). Previous variable valve control technologies could not regulate valve duration, as the valve’s closing timing was subordinate to opening timing and could not respond to diverse driving situations. However, the new CVVD technology is a much more efficient solution to this situation as it adjusts the duration of how long a valve stays open.
When the vehicle is maintaining a constant speed and requires low engine output, the CVVD opens the intake valve to complete the compression stroke. This helps to improve fuel efficiency by reducing the resistance caused by compression. On the other hand, when engine output is high, such as when the car is driving at a high speed, the intake valve is closed at the beginning of the compression stroke to maximize the amount of air used for the explosion, thus enhancing the torque and in-turn improving acceleration.
Smartstream G1.6 T-GDi Engine
The new Smartstream G1.6 T-GDi engine was unveiled alongside the new CVVD technology. This engine is a V4 gasoline turbo unit which can produce about 180 hp and around 265 Nm of peak torque. This new powertrain is the first to utilize Hyundai Group’s new CVVD technology and also features a Low-Pressure Exhaust Gas Recirculation (LP EGR) system to further optimize fuel efficiency. The new Smartstream G1.6 T-GDi engine will be applied in the Hyundai Sonata Turbo, which is set to launch in the second half of this year. This car debut will be the first in the new Hyundai and Kia vehicle series, which will be featuring the newly developed and completely optimized CVVD engine.
“The development of the CVVD technology is a good example how Hyundai Motor Group is strengthening our powertrain technology,” said Albert Biermann, President and Head of Research and Development Division at Hyundai Motor Group. “We will continue our innovation efforts to bring forth paradigm shifts and ensure the sustainability of our business model.”