摘要
通过瞬时转速波动来分析回转机械故障是机械诊断领域的一个热点问题,其中瞬时转速波动特征的准确获取是其关键。已有方法通过对编码器输出的位置信息进行差分来计算瞬时转速,由于差分的幅频特性与微分的幅频特性理论上存在较大偏差,在后续的波动幅值识别中会产生较大误差。针对这一问题,提出一种基于数字微分器的转速波动提取方法,该方法通过有限冲击响应滤波器对微分特性进行逼近,有效避免了传统方法的幅值衰减问题,进而提高了估计精度,准确实现数控机床传动机构的振动溯源。
The fluctuation analysis of angular speed signal is an effective way to recognize the incipient faults for rotating machinery. In this approach, fluctuation parameter extraction is the key. In current methods, the instantaneous angular speed is estimated by using central difference method. However, there is a significant difference in the magnitude response between central difference method and the differential operation, which will lead to large error in fluctuation magnitude extraction. Under this background, an instantaneous speed estimation method based on digital differentiator is established. The magnitude response of differential operation is approximated by finite impulse response filter in the proposed approach. This method can avoid magnitude attenuation effectively. The magnitude of fluctuation can be obtained with more accuracy for this reason. The effectiveness of proposed method is verified by using some simulations and experiments on a CNC machine tool. The vibration source of the rotary indexing table is identified successfully by using the proposed method.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2012年第22期1-6,共6页
Journal of Mechanical Engineering
基金
国家杰出青年科学基金(51125022)
国家自然科学基金(51005173)
高等学校博士学科点专项科研基金(20110201110025)
制造过程测试技术-省部共建教育部重点实验室开放基金资助项目
关键词
中心差分法
瞬时转速波动
数字微分器
故障诊断
振动溯源
Central difference method Instantaneous angular speed fluctuation Digital differentiator Fault Diagnosis Error source identification
