电控旁通阀涡轮增压器匹配计算研究

采用发动机性能仿真软件GT-power建立了带废气旁通阀电控系统的涡轮增压汽油机模型,基于增压压力随旁通阀开度变化的情况,确定了控制系统的特性参数值.根据不同增压压力下涡前压力的变化规律以及汽油机动力性能的要求对废气旁通阀开度进行标定,分析了增压器与汽油机联合运行性能并进行了实验验证.结果表明,选配的小尺寸涡轮确保了汽油机的低速性能;建立的控制系统实现了对增压压力多目标值的连续控制,高速时没有发生因增压压力过高而导致爆燃和增压器超速的现象.

Matching Simulation of an Electronically Controlled Waste Valve Turbocharger

A simulation model of turbocharged gasoline engine with electronically controlled waste valve system was built with the software of GT power. Based on the condition of boost pressure changing with the waste valve opening, characteristic values of the control system were obtained. According to the change rules of exhaust back pressure under different boost pressures, the waste valve opening was calibrated on the basis of the requirements of power performance of the engine, the matching performance between the turbocharger and the gasoline engine was analyzed, and then, test verification was conducted.The results have shown that matching a small diameter turbine can ensure the engine performance at low speed condition; the electronically controlled system can realize the continuous control of boost pressure target value; and the problems of deflagration and turbocharger super speed caused by too high boost pressures can be resolved at high speed conditions.