柴油机可变喷嘴增压器控制逻辑设计与参数标定

摘要

In order to meet the emission legislation and to increase the efficiency of the engine and to enhance dynamic charge response, the control logic of the boost pressure was constructed for the diesel engine in the light - duty truck equipped with variable nozzle turbocharger （VNT）. A boost pressure MAP was looked up by the controller according to engine speed and the fuel oil injec- tion quantity to determine target boost pressure. A control structure combined the open - loop pre - control with the closed -loop PID control was adopted to control the boost pressure, then a basic boost pressure MAP and a pre - control MAP and the PID parameter factor MAP was calibrated through the engine emission test. The practice control test on the engine test bench was conducted. The results show that the setting value of the boost pressure can be effectively tracked by the actual boost pressure of the engine, and control errors are less than 8%.%为了满足排放法规、提高发动机的效率和加快动态充气的响应，针对配置可变喷嘴涡轮增压器（VNT）的轻型卡车柴油机，设计了增压压力控制逻辑。控制器根据发动机转速和喷油量查询增压压力脉谱（MAP），确定目标增压压力。采用开环预控制和闭环PID控制相结合的控制结构对增压压力进行控制，并通过排放试验标定了增压压力基本MAP、预控制MAP和PID参数因子MAP。发动机试验台上的实际控制试验结果表明，发动机实际的增压压力能够有效跟踪设定值，控制误差不超过8％。