The high performance of the Kohler "Power Unit"
Compactness and power, reliability and fuel economy. These are the main strengths of the Power Unit line, KDI diesel engines designed expressly by Kohler Engines for small and medium power generators. It is a full range of “plug and play” engines, with off-the-shelf components and accessories designed to provide a complete solution in every detail and ready for installation. They cover a range from 20 to 60 KVA with a frequency of 50 Hz (1500 rpm) and from 20 to 70 KVA with a frequency 60 Hz (1800 rpm), notable not only for their superior performance, but also for their decidedly contained noise and vibration levels. From a construction point of view, the most innovative feature of the Power Unit line is the replacement of the traditional pre-chamber architecture with a mechanical direct injection system (for aspirated and turbocharged engines), accompanied by the introduction of four valves per cylinder. This significant technical innovation has allowed Kohler Engines to comply with emissions limits set by the regulations, while also optimizing the combustion process, improving efficiency and reducing fuel consumption. The Power Unit line can achieve high power densities. This means that the new engines are able to deliver the same power as more vigorous engines, but with lower displacements than those necessary up to now. In short, the Power Unit range will likely be appreciated by end users for the fuel economy (up to 3% lower) and the manageability in mobile applications. It will also be appreciated by OEMs, who can achieve a significant reduction in overall size of the generators (between 15% and 30% less) for the same power. This will result in reduced costs of production, transport and storage. Finally, as highlighted in the manufacturer’s spec sheet, the combustion optimization allows a further reduction in the engine compartment size (especially with regard to the radiator and fans) because reducing the heat released by the engine improves its cooling process.
by Giovanni M. Losavio