共轨柴油机电控系统若干关键技术

Key technology of electronic controlled system of common-rail diesel engine

为了使柴油机排放能够满足国III及以上法规要求,采用电控高压共轨燃油喷射系统来精确控制喷油压力和喷油时刻,实现燃油多次喷射.研究发现,电磁干扰、喷油器老化、喷油器机械加工精度等原因会导致共轨燃油系统喷油误差,尤其是小油量喷射时的误差.通过分析共轨燃油喷射系统控制器的硬件电路和软件算法,分析喷油器的喷油延时特性.提出控制器驱动电路控制逻辑、地线抗电磁干扰方法和小油量喷油一致性自学习算法.结果表明,应用这些方法设计的控制单元能够改善喷油器抗老化性能,弥补机械加工精度对小油量喷射的影响,改善发动机排放性能.

Common rail fuel injection system was utilized for diesel engine in order to fulfill national-III and above emission limits.Fuel pressure and injection time were accurately controlled,and multiple injection was realized.Results show that the electromagnetic interference,injector aging and injector manufacture precision can lead to wrap in fuel injection,especially when the injection quantity is small.Then the hardware circuit and software algorithm of common rail fuel injection system control unit,and the delay characteristic of the injector were analyzed.Injector drive circuit control logic,electronic controlled unit electromagnetic interference,and self-study algorithm of little quantity oil injection coherence were presented.Results showed that the anti-aging characteristic and the precision of the injector were improved,and the emission of the diesel engine was improved.