为了解决在直升机结构响应主动控制飞行试验中出现的控制算法在复杂外扰环境中收敛速度较慢、易受外扰影响而导致控制发散等问题,在原有算法基础上,提出采用变步长因子法以提高算法收敛速度,同时增强其对于时变情况的跟踪能力;采用添加约束权函数方法来降低各类干扰信号如量测干扰等对算法稳定性的不利影响。用自由一自由梁机体模型在有限元软件上对改进算法的可行性进行了仿真。仿真结果表明,改进算法能有效改善在复杂外扰影响下直升机稳定性控制的效果,为进一步开展试验验证研究奠定了良好的基础。
In order to solve the problem that the convergence speed of the adaptive filtering algorithm with online secondary path modeling in time domain becomes lower, sometimes even become divergence, which occurred in the research of active vibration control of helicopter under complex disturbances environment. Based on the original algorithm, a variable step size was used instead of the fixed one to increase the speed of convergence. And a weight - constrained filtered - x LMS algorithm was used to reducing the influence of disturbances to the secondary path. Simulations have been conducted based on the finite element model of free - free beam. Results show that the two proposed methods are able to enhance the ability of active vibration control system for helicopter with complex disturbances effectively, as the basis for further study.