船用大型低速二冲程柴油机的动态模型

Dynamic Modeling of Large Two-Stroke Marine Diesel Engine

准确的模型是实现柴油机优化控制目标的关键,平均值模型能够较好的实现这个目标。在综合考虑扫气系数和容积效率对过量空气系数影响的基础上,采用随过量空气系数变化的气体常数和比热比,建立了大型低速二冲程柴油机的平均值模型。以6S60MC型船舶柴油主机为母型机进行系统仿真,结果显示,建立的平均值模型具有较好的准确性及动态特性。目前此模型已应用于船用柴油机控制算法的设计、分析及仿真系统中。

Precise model is a key issue in optimal control of diesel engine systems. Mean value model can realize this objective. This paper establishes a dynamic mean value model for diesel engine based on effect of both scavenging coefficient and volumetric efficiency on excess air ratio. Variable gas constant and specific heat ratio are considered and these influential factors are usually neglected by other researches. Using 6S60MC diesel engine of MAN B＆W Company as an objective, the system simulation studies are conducted to evaluate the model correctness in marine diesel engine systems. Simulation results show that the established model gives better precision and dynamic characteristics. The model can be used in developing, analyzing and simulating advanced control algorithms for marine diesel engine systems.