Research on intelligent common rail pressure control influenced by pressure fluctuation

The control performance of the common rail pressure affects the power and emissions of the diesel engine. The pressure fluctuation caused by the multiple injection and pulse fuel pumping in high pressure common rail system would significantly disturb the control performance of the rail pressure. In this paper, the model of rail pressure fluctuation is established, which is combined with the classic Bernoulli common rail model into a simulation model. The comparative researches are conducted between the classic and the intelligent PI controller, and the intelligent PI control under different pressure states. By analyzing the results with pressure fluctuation, the observer and the loop-shaping methods are suggested and verified for improving the intelligent control performance.