计算阶次分析中避免阶次混叠的滤波定阶方法及其应用

针对计算阶次分析中的阶次混叠现象，分析了各阶次信号分量在频域范围的对应关系，提出并分析了在相同转速区间内信号的各阶次分量会发生频率重叠的问题；在此基础上提出了使用滤波器限制频率、确定阶次的方法，推导了滤波器截止频率选择和滤波后信号角域重采样阶次的确定原则。通过仿真信号分析和实际信号验证，提出的方法成功均能有效的阶次混叠问题，有效确定和降低了角域重采样阶次。

A method to avoid order aliasing in COT based on filtering

To solve the order ailiasing problem, this paper analysed the corresponding relationship between different order signal component and frequency domain, proposed and analysed the problem that different order component overlaps in frequency domain during the same rotational speed interval. According to this, the paper proposed a method using filter to limit frequency and order, deduced the principles how to choose filter cut-off frequency and angular domain resampling order. The simulation signal analysis and actual experiment both show that, the method solved order aliasing problem successfully.