针对内燃机瞬时转速计算精度低、对采样频率鲁棒性差的问题,提出了基于固有时间尺度分解(Intrinsic Time-scale Decomposition,ITD)和邻域差分能量算子解调(Energy Operator Demodulation,EOD)的瞬时转速计算方法。利用自适应波形匹配算法对原采样信号进行端点延拓,然后基于ITD算法从信号中提取包含瞬时转频的单分量信号,再对单分量信号进行邻域对称差分,并将差分结果输入传递函数计算能量算子,进而求出内燃机的瞬时转频和瞬时转速。仿真和实测信号研究证明了本方法计算速度快、精度高且频率鲁棒性好。
In order to solve the problems of low calculation precision of instantaneous speed and poor robustness of sampling frequency,the calculation method of intrinsic time-scale decomposition(ITD)and neighborhood difference energy operator demodulation(EOD)was proposed.The end of original signal was extended with the self-adaptive waveform matching method and the single component signal containing instantaneous rotation frequency was extracted with ITD method.Neighborhood symmetric difference of the single component signal was calculated,the result of difference was used as the input of transfer function to calculate energy operator,and then the instantaneous rotation frequency and speed of internal combustion engine were calculated.The comparison of simulated and measured signal proved that the method had good speed,accuracy and frequency robustness.