| How to achieve the high efficiency and clean combustion of the diesel enginehas been paid more and more attention for the shortage of energy and deterioration ofenvironment. High efficiency and clean burning depends on the advanced combustiontechnology, the Combined combustion strategy of low temperature combustion andhigh density low temperature combustion, which is Proposed by the author’s team, isa effective way to achieve the high efficiency and clean burning of the diesel enginein the entire load.The combined combustion of low temperature combustion and high density lowtemperature combustion couldn’t be realized without the electronic control unit whichincludes software and hardware, Hardware is the basis of the electronic control unit,and the module of power supply is the energy source of the ECU hardware，itprovides the energy of the various voltages for the hardware.In order to develop a new generation of diesel engines ECU the author hasre-optimized and designed the power supply module based on the author’s grouppreliminary work. Selected a more suitable low-voltage power supply chips MC33730for the core chip MPC5554, and modular designed it for future debugging in hardwaredevelopment process, and also validate the function of the power module throughexperiments. It was found that with respect to the power chip of the previousgeneration, the chip MC33730has higher efficiency, better stability of output voltage,and it could be better able to meet the demand of the diesel engine ECU.In the aspect of the Injector drive power supply, the author has conducted adetailed analysis of the working process of the booster circuit from the angle of thecharge amount transfer, and derived the mathematical relationship of the boost voltagerecovery time which has good agreement with the experimental results, and carriedout a detailed analysis of the continuing power after the inductor current exceeds themaximum inductor saturation current. And found that the boost voltage recovery timeafter saturation of the inductor current fluctuations in the back and forth between thetwo values, and the conversion efficiency of the booster circuit reduce drastically first,and then slow down. Finally, select the best components and control parameters forthe boost circuit.In the aspect of engine experiments, the author conducted a detailed analysis ofthe pressure regulating portion of the two stage turbo supercharger. By comparing the effect of the turbo-side and compressor-side deflating on engine performance andemissions, found that both the turbo-side deflating and compressor-side deflating canimprove the engine effective thermal efficiency, lower the engine effective fuelconsumption rate and reduce NOx and Soot emissions,However, the amplitude of thecompressor-side is relatively smaller, and analyzed the effect of the turbo-side and thecompressor-side coordination deflating on engine performance and emissions. Foundthat it would be tend to get the best point of compromise engine performance andemissions by turbo-side and the compressor-side coordination deflating. |
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