一种基于延迟系数技术的次级通道在线辨识新方法

A new method for online recognition of secondary path based on delay coefficient technique

工程中控制目标区域改变、误差传感器位置变化或其他因素会引起的次级通路的实时改变,精确的辨识次级通道传递函数可以有效的提高噪声主动控制效率。基于人工延迟系数技术提出一种新的次级通道在线辨识方法,推导出主动控制环节收敛步长和次级通路建模环节收敛步长的调整表达式,从收敛性能和算法计算量两方面跟传统算法进行比较,得出其改进优势。给出新的附加噪声功率控制策略,实现对附加随机噪声功率的调节,在保证系统稳定的情况尽量消除其对残余噪声的影响。最后,进行了算法仿真和噪声主动控制实验,结果表明该算法具有收敛性好,降噪性能高的特点。

Changes of control target area and error sensor position or other factors may lead to the real-time change of secondary path in practical engineering. Accurate identification of secondary path transfer function can effectively improve the efficiency of noise active control. Here,a new secondary path online modeling method based on delay coefficient technique was proposed. The adjustment rules of the convergence step lengths of active control stage and secondary path modeling stage were derived. Comparing with the traditional algorithms for convergence performance and the computational complexity,the improvement advantages of the new method were gained. The proposed algorithm also introduced an auxiliary noise power scheduling for achieving the adjustment of the additional random noise power to ensure the system stability and eliminate its influence on the residual noise as much as possible. Numerical simulations and noise active control tests showed that the proposed method has better performances of convergence and noise reduction than the existing methods do.