In 2010, when Swedish luxury carmaker Volvo and Chinese car giant Geely joined forces, the two saw the future trend in the automotive industry: demand for even more efficient engines and one that could easily integrate with electrified powertrain.
To meet this future requirement Volvo with Geely’s support developed the VEA or Volvo Engine Architecture, a new modular engine architecture for three and four cylinder engines developed from the onset to support electrified powertrain systems that may be developed in the near future.
This led to the development of the 1.5TD (turbocharged direct injection) engine, a small yet powerful engine that has the potential to meet even the most stringent standards, the upcoming Euro 7.
Geely’s 1.5TD was jointly developed by Geely and Volvo at Volvo R&D center in Gothenburg (Sweden); CEVT China Euro Vehicle Technology in Gothenburg; and Geely Research Institute in China.
Small yet powerful
The small displacement 1.5TD is more efficient yet produces power comparable to larger engines. Modern day turbocharger and supercharger technology can turn a well-designed four cylinder 2.0L engine into a world-class race winning powerhouse as Volvo and Polestar has shown in the World Touring Car Championship and World Touring Car Cup.
After developing a four cylinder 2.0L engine, Volvo and Geely began work on a smaller, even more efficient three cylinder 1.5TD engine for compact and hybrid models.
The smaller three-cylinder 1.5TD leaves room to accommodate hybrid systems, giving designers more freedom. The lighter weight improves fuel economy and makes it easier to achieve a more balanced chassis in front wheel drive models improving drive performance.
3-cylinder with less vibration
The main concern consumers have with odd numbered cylinder engines is perceivable engine vibration. However, Geely and Volvo did not think this was an unsolvable problem as Volvo, for years, has utilized a five cylinder engine and has extensive experience developing engines for the premium market segment.
In addition, the latest engine technologies in the Geely 1.5TD engine ,such as counterweighted crankshafts, dual mass flywheel with centrifugal pendulum absorber damper, single balancing shaft, low noise timing belt, high stiffness oil pan, asymmetric oil pump impeller, engine compartment vibration dampener, etc. have effectively eliminated perceivable engine vibrations by driver and passenger inside the vehicle.
In fact, NVH in models utilizing Geely 1.5TD engine is on par or better than some equipped with four cylinder engines.
By incorporating electrified systems, perceivable vibrations in the 1.5TD can be reduced even further. Most vibration is felt during the engine start-up period and at lower engine speeds, however with addition of hybrid electric systems, engine start-up can be made near instantaneous and low-speeds drive can be assisted by the electric motor.
Because the engine is based on a new architecture, Geely tested and validated the 1.5TD above and beyond the industry standard. In fact, the 1.5TD engines are designed to last 15 years or 350,000 km, much higher than the industry standard 10 years or 200,000 km.
Geely and Volvo have so far developed three base variants of the three-cylinder engine. Additional tuning has also been made to meet the localized needs of different markets. The latest variant, 1.5T Miller has been designed specifically for hybrid electric vehicle application by adjusting variable valve timing to enable the engine to run on the fuel efficient miller cycle.
Charles E. Buban is an old timer in the Philippine automotive journalism scene. He first started covering the automotive beat in 2003, writing news and reviews of new models and car tech, among other car-related stuff. When not writing about cars, he could often be seen riding his mountain bike or doing long walks in the hope of catching a couple of legendary Pokemons.