Muzzle voltage noise suppression and application for augmented electromagnetic railgun based on VMD-OptShrink
-
摘要: 利用电磁轨道炮炮口电压测量信号可以计算出发射过程中滑动电枢与铜轨道表面的接触电阻以分析接触特性。由于发射器增强轨道的特殊结构会产生幅值很大的反向感应电动势,且存在脉冲形成网络的放电时序问题,导致检测到的炮口电压波形会受到系统噪声的干扰,难以准确计算出接触电阻。针对此问题,提出一种基于VMD-OptShrink的炮口电压系统噪声压制方法去除炮口电压中的锯齿状噪声,该方法首先利用变分模态分解(Variational Mode Decomposition,VMD)可实现依据频率特性进行信号时域分解的特点,对炮口电压信号进行时频域的模态分解,然后在时频分解域内利用OptShrink对分解信号进行低秩成分提取,得到去噪后的炮口电压,最终解算出接触电阻用于分析轨道炮枢轨接触特性。试验结果表明,该方法可以很好地压制炮口电压系统噪声,计算出的枢轨接触电阻波形光滑,有利于分析枢轨接触特性;枢轨接触电阻在发射初期变化剧烈,迅速降低,之后呈现缓慢波动上升的特点,直至电枢滑动出炮口接触电阻骤增。该分析方法对工程中电磁轨道炮发射状态监测提供了一种新的可靠参考。Abstract: Utilizing the muzzle voltage of the electromagnetic railgun, the contact resistance between the sliding armature and the copper rail surface during the launch process can be calculated to analyze the contact characteristics. However, the muzzle voltage signal contains a large amplitude of reverse induced electromotive force due to the complex augmented rails structure of the launcher. Meanwhile, the firing sequence of the pulse forming network disturb the detected muzzle voltage signal as system noise interference. Therefore, it is difficult to accurately calculate the contact resistance. To solve this problem, a noise suppression method of muzzle voltage system based on VMD-OptShrink is creatively utilized to suppress jagged noise. In this method, variational mode decomposition (VMD) can decompose the muzzle voltage signal in time-frequency domain according to the frequency characteristics. Then OptShrink is used to extract the low-rank components of the decomposed signal to obtain the denoised muzzle voltage. Finally, the contact resistance is calculated to analyze the armature-rail contact characteristics. The test results show that this method can suppress the muzzle voltage system noise well. The calculated armature-rail contact resistance waveform is smooth, which is conducive to the analysis of the armature-rail contact characteristics. The armature-rail contact resistance decreases rapidly at the initial stage of launching, then it fluctuates slowly until the armature slides out of the muzzle and the contact resistance increases sharply. The method proposed in this paper provides a new and reliable reference for the launching performance monitoring of electromagnetic railgun.
-
表 1 发射器参数
Table 1. Parameters of launcher
armature displacement length/mm inductance gradient/(μH·m−1) caliber of launcher/mm charging voltage of PFN/kV current peak value/kA armature muzzle velocity/(m·s−1) 1600 0.7 10 3.3 246.4 1672.3 -
[1] 王振春, 鲍志勇, 曹海要, 等. 增强型电磁轨道炮电枢轨道接触特性研究[J]. 兵工学报, 2018, 39(3):451-456 doi: 10.3969/j.issn.1000-1093.2018.03.005Wang Zhenchun, Bao Zhiyong, Cao Haiyao, et al. Research on contact characteristics of armature and rail in augmented electromagnetic railgun[J]. Acta Armamentarii, 2018, 39(3): 451-456 doi: 10.3969/j.issn.1000-1093.2018.03.005 [2] 陈允, 徐伟东, 袁伟群, 等. 电磁发射中铝电枢与不同材料导轨间的滑动电接触特性[J]. 高电压技术, 2013, 39(4):937-942 doi: 10.3969/j.issn.1003-6520.2013.04.025Chen Yun, Xu Weidong, Yuan Weiqun, et al. Sliding electrical contacts between aluminum armature and different material rails in railgun[J]. High Voltage Engineering, 2013, 39(4): 937-942 doi: 10.3969/j.issn.1003-6520.2013.04.025 [3] Xu Weidong, Yuan Weiqun, Sun Yaohong, et al. Research on the sliding electrical contact of the rapid fire railgun[J]. IEEE Transactions on Plasma Science, 2013, 41(5): 1542-1546. doi: 10.1109/TPS.2013.2252190 [4] 李鹤, 雷彬, 李治源, 等. 电磁轨道炮试验过程中枢轨界面的接触电阻特性[J]. 高电压技术, 2013, 39(4):911-915 doi: 10.3969/j.issn.1003-6520.2013.04.021Li He, Lei Bin, Li Zhiyuan, et al. Contact resistance characteristics of the interface between armature and rail in electromagnetic railgun launching tests[J]. High Voltage Engineering, 2013, 39(4): 911-915 doi: 10.3969/j.issn.1003-6520.2013.04.021 [5] 巩飞, 翁春生. 电磁轨道炮固体电枢熔化波烧蚀过程的三维数值模拟研究[J]. 高电压技术, 2014, 40(7):2245-2250Gong Fei, Weng Chunsheng. 3-D numerical study of melt-wave erosion in solid armature railgun[J]. High Voltage Engineering, 2014, 40(7): 2245-2250 [6] 何勇, 宋盛义, 关永超, 等. 电磁轨道炮高速滑动接触电阻的定量表征[J]. 强激光与粒子束, 2014, 26:045007 doi: 10.11884/HPLPB201426.045007He Yong, Song Shengyi, Guan Yongchao, et al. Quantitative expression of sliding contact resistance between armature and rail in railgun[J]. High Power Laser and Particle Beams, 2014, 26: 045007 doi: 10.11884/HPLPB201426.045007 [7] Chen Lixue, He Junjia, Xiao Zheng, et al. Experimental study of armature melt wear in solid armature railgun[J]. IEEE Transactions on Plasma Science, 2015, 43(5): 1142-1146. doi: 10.1109/TPS.2015.2418784 [8] 刘旭堃, 于歆杰, 刘秀成. 电容储能型脉冲电源分时分段触发策略自动计算方法[J]. 电工技术学报, 2016, 31(11):186-193 doi: 10.3969/j.issn.1000-6753.2016.11.022Liu Xukun, Yu Xinjie, Liu Xiucheng. An automatic calculation method for the triggering strategy of the capacitive pulsed-power supply[J]. Transactions of China Electrotechnical Society, 2016, 31(11): 186-193 doi: 10.3969/j.issn.1000-6753.2016.11.022 [9] 常馨月, 于歆杰, 刘旭堃. 一种实现电枢出膛速度控制的电磁轨道炮脉冲电源触发策略[J]. 电工技术学报, 2018, 33(10):2261-2267Chang Xinyue, Yu Xinjie, Liu Xukun. A velocity-controlling triggering strategy of capacitive pulsed power supply electromagnetic railgun system[J]. Transactions of China Electrotechnical Society, 2018, 33(10): 2261-2267 [10] Rada N M, Engel T G. A railgun test bench and standardized methodology for muzzle voltage noise analysis[J]. IEEE Transactions on Plasma Science, 2015, 43(5): 1634-1641. doi: 10.1109/TPS.2015.2406702 [11] Dragomiretskiy K, Zosso D. Variational mode decomposition[J]. IEEE Transactions on Signal Processing, 2014, 62(3): 531-544. doi: 10.1109/TSP.2013.2288675 [12] Ma Haitao, Yan Jie, Li Yue. Low-frequency noise suppression of desert seismic data based on variational mode decomposition and low-rank component extraction[J]. IEEE Geoscience and Remote Sensing Letters, 2020, 17(2): 337-341. doi: 10.1109/LGRS.2019.2919795 [13] Nadakuditi R R. OptShrink: an algorithm for improved low-rank signal matrix denoising by optimal, data-driven singular value shrinkage[J]. IEEE Transactions on Information Theory, 2014, 60(5): 3002-3018. doi: 10.1109/TIT.2014.2311661 [14] Li Juxiang, Cao Bin, Fan Zhiguo, et al. Judging the abnormal rail-armature contact states with waveforms of B-dot probes[J]. IEEE Transactions on Plasma Science, 2017, 45(7): 1274-1280. doi: 10.1109/TPS.2017.2705147 [15] 李菊香, 曹斌, 范志国, 等. B探针测速及基于激光方法的精度研究[J]. 电工技术学报, 2020, 35(s2):327-332Li Juxiang, Cao Bin, Fan Zhiguo, et al. Research on speed measurement by B-probe and precision based on laser method[J]. Transactions of China Electrotechnical Society, 2020, 35(s2): 327-332