| 引用本文: | 李城汐,蒋启龙,陆凡,刘东.分段自适应阈值小波的地铁塞拉门数据压缩方法[J].哈尔滨工业大学学报,2020,52(9):101.DOI:10.11918/201904134 |
| LI Chengxi,JIANG Qilong,LU Fan,LIU Dong.Data compression method for metro vehicle plug door based on segmented adaptive wavelet threshold[J].Journal of Harbin Institute of Technology,2020,52(9):101.DOI:10.11918/201904134 |
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| 摘要: |
| 针对地铁塞拉门进行PHM应用诊断时产生海量数据的压缩问题,提出一种基于分段自适应阈值的小波压缩算法,通过原始数据的自适应分段和自动调节各段阈值放大系数,实现了兼顾精度和大压缩比的数据压缩. 针对塞拉门电机电流采样数据能量不集中、幅值变化较大的特点,对采集到的原始数据进行自适应分段处理,通过预设阈值自动调整各段小波阈值放大系数,再使用一维小波对数据进行压缩处理,在满足重构信号精度的前提下,实现了数据的大压缩比压缩,大大减小了需要存储的数据量. 以江苏省无锡市地铁2号线查桥车辆段段内测试数据为例,选用db3小波进行4层小波压缩,进行基于分段自适应阈值小波的地铁塞拉门数据压缩测试. 试验结果表明:新的压缩方案在整体失真率0.3%的前提下,实现了2.56%的超高压缩比,满足了实际工程应用需求,验证了该方案的可行性和有效性. |
| 关键词: 地铁塞拉门 数据压缩 小波变换 分段自适应 动态阈值 |
| DOI：10.11918/201904134 |
| 分类号:TU375 |
| 文献标识码:A |
| 基金项目:国家自然科学基金(61531016) |
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| Data compression method for metro vehicle plug door based on segmented adaptive wavelet threshold |
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LI Chengxi,JIANG Qilong,LU Fan,LIU Dong
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(School of Electrical Engineering, Southwest Jiaotong University, Chengdu 610000, China)
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| Abstract: |
| In view of the problem of mass data compression generated during the diagnosis of metro vehicle plug door by PHM, a wavelet compression algorithm based on adaptive sectional threshold was proposed. Through the adaptive segmentation of the original data and the automatic adjustment of the amplification factor of the threshold of each segment, data compression with high accuracy and large compression ratio was achieved. To tackle the problems that the energy of the sampling current of the plug door motor was not concentrated and the amplitude varied greatly, the collected original data was adaptively segmented. Amplification factors of each segment of the wavelet threshold were adjusted automatically by a preset threshold, and then one-dimensional wavelet was used for data compression. On the premise of satisfying the accuracy of reconstructed signals, the method achieved high data compression ratio and greatly reduced the data amount to be stored. Data from Chaqiao Depot of Metro Line 2 in Wuxi, Jiangsu Province was obtained, and data compression test for metro vehicle plug door was carried out based on segmented adaptive wavelet threshold by selecting db3 wavelet for 4-layer wavelet compression. Results show that the test realized ultra-high compression ratio of 2.56% with the overall distortion ratio of 0.3%, indicating that the method is feasible and effective and can meet the requirements of actual engineering application. |
| Key words: metro vehicle plug door data compression wavelet transform segmented adaptive dynamic threshold |
