起动工况驾驶性评价指标特征点识别方法

Identification Method for Feature Points of Drivability Evaluation Indicators in Starting Condition

针对车辆起动过程的驾驶性评价指标特征点会因发动机转速波形特异性强和外界干扰而造成识别不准确的问题,本文中提出了一种从信号预处理到特征点识别的一套方法。根据驾驶性评价指标和转速曲线时域特征确定了特征点;结合形态滤波-经验模态组合方法对转速信号进行滤波处理;将D-S证据理论与句法模式相结合应用到特征点的识别中。实验结果表明,该方法能有效地识别起动工况发动机转速曲线的评价指标特征点,为后续驾驶性评价指标的获得提供了客观依据。

Aiming at the problem that the feature points of drivability evaluation indicators in vehicle start process are inaccurately identified due to the strong specificity of engine speed waveform and external interference, a set of methods from signal preprocessing to feature point identification are proposed in this paper. The feature points are determined according to drivability evaluation indicators and the time domain features of rotational speed curve. Morphological filtering combined with empirical modal decomposition is adopted to conduct filtering processing on rotational speed signals, while the combination of D-S evidence theory and syntactic pattern is applied to feature point identification. The results of experiment show that the method proposed can effectively identify the feature points of evaluation indicators on engine speed curve in starting condition, providing an objective basis for obtaining drivability evaluation indicators later on.