SCR控制策略研究

Research of Control Strategies for SCR Systems

在自开发选择性还原(SCR)系统供给计量泵和电控系统的基础上进行了SCR控制策略研究。根据SCR系统降低柴油机NOx排放的原理,进行SCR电控系统方案设计和控制策略研究,设计了SCR系统总体工作流程。基于开环控制原理设计了目标尿素需求计量策略,根据状态转移机制设计了计量泵状态及故障跳转管理策略。测试结果表明,该系统运行稳定,执行效率高,可满足柴油机SCR系统控制的需求。

The control strategies were researched based on the metering pump and electronic control unit （ECU） of the selective catalytic reduction （SCR） system. The principle of how the urea-SCR reduces NOx emissions from diesel engines was introduced. The system works in an open loop configuration where a pre-programmed map of engine NOx emissions is used to control the ammonia injection rate. Fault diagnosis strategies of the metering pump were developed according to the state transfer mechanism. The experiment results show that this stable and high-efficiency system meets the control requirements of the SCR system.