利用振动信号测量发动机转速是一种不解体检测的重要方法，但其对发动机振动频率要求较高，因此转速急剧变化时，对测量精度影响较大。提出了基于希尔波特包络和自相关的新方法。首先利用小波变换消除基线漂移，再通过短时时间窗进行类稳态分析，并采用希尔伯特包络和三次自相关对信号进行时域分析,计算短时窗内的发动机转速，最后通过移窗方法得到连续的发动机转速。通过在发动机台上进行变工况实验，同步采集振动信号和转速传感器信号进行对比分析，在急加速条件下转速测量最大误差在1.4%以下，能够有效的满足柴油发动机转速的实时性和精确性要求，在车辆不解体检测和无负荷测功方面有很大应用前景。
Abstract
It is an important method to measure the engine speed by using vibration signal, but it has a high demand on the engine vibration frequency, so it has a great influence on the measurement accuracy when the speed changes dramatically. A new method based on Hilbert envelope and autocorrelation was proposed. Using wavelet transform to eliminate the baseline drift firstly. Then the quasi-steady-state analysis is carried out by means of a short-time window, and the Hilbert envelope and three autocorrelation are used in time domain analysis to calculate the rotational speed of the engine in a short-time window. Finally, the continuous engine speed is obtained by moving the window method. Through the variable working condition experiment on the engine bench, the synchronous acquisition vibration signal and the rotating speed sensor signal are compared and analyzed, and the maximum error of speed measurement under the condition of rapid acceleration is less than 1.4%. It can effectively meet the requirements of real-time and accuracy of diesel engine’s speed, and has a great application prospect in the field of non-disassembly test and unloaded power detection.
关键词
柴油发动机转速 /
振动信号 /
基线漂移 /
短时窗 /
希尔伯特变换 /
自相关
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Key words
Diesel engine speed /
Vibration signal /
Baseline drift /
Short-time window /
Hilbert transform /
Autocorrelation
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参考文献
[1] 李华英,果霖,付宏财. 基于单片机的发动机转速测量系统设计[J]. 云南农业大学学报(自然科学),2015, 30(2): 294-297.
LI Huaying, GUO Lin,FU Hongcai. Engine Rotational Speed Measuring System Design Based on Single Chip Computer. Journal of Yunnan Agricultural University 2015,30(2):294一297.
[2] 丁柏,宋翔. 基于振动基频的一种发动机转速测量新方法[J]. 长江大学学报(自科版),2013, 10(28): 76-79.
DING Bai, SONG Xiang. A new engine speed measurement method based on vibration fundamental frequency. Journal of Yangtze University(Nat Sci Edit),2013, 10(28): 76-79.
[3] LIN Hinbin, DING Kang. A new method for measuring engine rotational speed based on the vibration and discrete spectrum correction technique[J]. Measurement, 2013,46(7):2056–2064.
[4] Sun Yiquan, Zhang Yingtang, Li Zhining, etal. Design on Instantaneous Rotational Speed Measuring Device of Engine[C]. International Conference on Instrumentation. IEEE, 2011:126-129.
[5] 蒋强,孙利生. 基于振动信号和小波变换的转速测量方法研究[J]. 汽车科技,2011,38(1):39-41.
JIANG Qiang,QIU Lisheng. Research on the Speed Measurement Based on the Vibration Signal and Wavelet Trousform. Auto Sci-tech, 2011,38(1):39-41.
[6] 林慧斌,丁康. 基于振动的发动机转速高精度动态测量新方法[J]. 振动工程学报,2012,25(5):595-601.
LIN Huibin, DING Kang. A high accuracy dynamical measurement method for engine rotation speed based on vibration[J]. Journal of Vibration Engineering, 2012,25(5):595-601.
[7] 张永生.基于Hilbert包络信号提取技术的LCR波超声应力检测系统研究[D].成都:电子科技大学,2013.
ZHANG Yongsheng. Study on the Extraction of Useful Segment with Hilbert Envelope for Stress Measurement by LCR一Ultrasonic[D].Chengdu: University of Electronic Science,2013.
[8] 张盈盈,潘宏侠,郑茂远.基于小波包和Hilbert包络分析的滚动轴承故障诊断方法[J].电子测试, 2010,17(6): 20-23.
ZHANG Yingying, PAN Hongxia, ZHENG Maoyuan. Rolling bearings fault diagnosis based on wavelet packet and Hilbert envelope analysis. Electronic Test, 2010,17(6): 20-23.
[9] Zhou Jia-Dong, Ouyang Guang-Yao, Gao Hong-Bin. Demodulation of Instantaneous Rotational Speed of Diesel Engine Based on Hilbert Transform[A]. Proceedings of 2009 9th International Conference on Electronic Measurement & Instruments（ICEMI’2009）Volume 2[C]. 2010.
[10] 衰文文. 基于振动分析的汽车发动机在线转速测量研究[D].天津:河北工业大学,2011.
YUAN Wenwen. Research on The Online Measurement of
Automobile Engine Speed Based on Vibration Analysis[D]. Tianjin: Hebei University of Technology,2011.
[11] 张文琼,刘肖琳,吴涛. 一种利用小波变换逼近信号滤除心电图基线漂移的方法[J]. 计算机工程与应用, 2005,41(20):222-224.
ZHANG Wenqiong, LIU Xiaolin, WU Tao. A Method Using Wavelet Approximation to Remove the Electrocardiogram Baseline Wander. Computer Engineering and Applications, 2005,41(20):222-224.
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