发动机与液力变矩器匹配工作点算法研究

Arithmetic of the Cooperating Point of Engine and Torque Converter

正确分析发动机与液力变矩器的共同工作输入和输出特性是液力传动车辆动力传动系最优匹配的基础。而发动机与液力变矩器共同工作特性分析的关键和难点是正确计算两者共同工作点。为了得到精确的计算结果,发动机净转矩外特性曲线采用高次拟合,并分别采用了N分法、牛顿法、直接求根法来求解其共同工作点。采用Matlab语言编程,并进行了实例计算和分析,结果表明3种方法都是计算发动机与变矩器共同工作点的有效方法。

Accurate analysis of cooperating input and output performance of engine and torque converter is the essential of matching hydrodynamic transmission vehicle power system.Accurate calculation of cooperating point is the difficulty and key of cooperating input and output performance analysis of engine and torque converter.Least square higher order polynomial fit was adopted for engine net torque performance curve to get a precise result.At the same time,N equal division method,Newton＇s method and direct extraction of root were applied respectively to calculate the cooperating point of engine and torque converter.Matlab program language was used and three methods were testified by practical calculation and analysis.The calculating results show that three methods are all effective for the calculation of cooperating point of engine and torque converter.