Electronics has greatly contributed to the operation of internal combustion engines. This is especially evident in the benefits that it has brought to drivers, such as enhancing the “Fun to Drive” experience and in reducing the cost of fuel. Moreover, this progress has resulted in minimizing environmental degradation, and yet continuing to support improvements in performance. In the diesel engine, which has superb fuel economy, the innovative progress has been achieved by the common rail technology. The common rail system has the features of high injection pressure control in all engine speed range, highly precise injection control and multiple injections per combustion cycle.
The latest 2nd generation of the DENSO common rail system features 1800 bar injection pressure, and five times multiple injection with fully electronic control to ensure precise small injection quantities. This technology has been commercialized into passenger car products in the European market. It has exceeded the requirements of the very strict European EURO IV exhaust gas regulation for PM and NOx without Diesel Particulate Filter(DPF). Additionally through electronic control, as a result of combustion control by multiple injections, combustion noise at idling is drastically reduced, which allows a level of quietness similar to gasoline engines.
The system creates those new functions by taking advantages of both high pressure technology and electronics technology. This paper presents the features of the second-generation common rail system focusing the new function by electronics as digital driving force to create consumer value.