摘要
针对S变换的窗函数固定,以及在检测扰动信号的起止时刻、幅值变化、相位变化时的检测精度不高的问题,在S变换中引入两个调谐因子,得到一种改进的S变换,并对改进的S变换进行傅里叶反变换得到TT变换,将改进的S变换与TT变换相结合应用到主要引起电压暂降的3种暂降源中,并在MATLAB软件上对这3种暂降扰动源信号进行了仿真分析。仿真结果表明,所提的方法比使用S变换方法在检测电压暂降信号上具有更高的检测精度和更好的效果,为更好地提取暂降特征信息以及暂降源的识别打下基础。
In view of the fixed window function of S-transformation and the problem of detection accuracy when detecting the start and end moments of disturbance signal, amplitude variation, and phase change, this paper introduces two tuning factors in S-transformation to obtain an improved one. S transform, and the inverse transform of the improved S transform to get the TT transform, the improved S transform and the TT transform are applied to the three sources of the disturbance that mainly cause the voltage sag, and on the MATLAB to the three a kind of temporary disturbance source signal was detected and analyzed. The MATLAB simulation results show that the proposed method has better effect and higher detection precision than the S-transform method in detecting voltage sags, which lays the foundation for better extraction of the characteristics of sags and identification of temporary sources.
引文
[1] 苗竹梅, 王冲.刘伟,等. 电子企业的电压暂降分析与对策[J]. 智能电网, 2016,4(12):1171-1174.
[2] 刘旭娜, 肖先勇, 汪颖. 电压暂降严重程度及其测度、不确定性评估方法[J]. 中国电机工程学报, 2014, 34(4):644-658.
[3] 吴丽娜. 电压暂降检测分析及抑制措施研究[D]. 保定: 华北电力大学,2015.
[4] 张淑清,李盼,师荣艳,等. 基于改进S变换的电能质量扰动分类新方法[J].仪器仪表学报,2015, 36(4):927-934.
[5] 梅娟, 黄纯, 戴栩生,等. 采用TT变换的电能质量扰动检测与分类方法[J]. 电力系统及其自动化学报, 2016, 28(3):24-29.
[6] 肖先勇,崔灿,汪洋, 等. 电压暂降分类特征可比性、相关性及马氏距离分类法[J]. 中国电机工程学报, 2015, 35(6):1299-1305.
[7] 刘超, 黎涛,王华. 静止无功补偿器接入的配网短路故障特征及保护整定策略[J]. 电力系统及其自动化学报, 2017, 29(6):113-117.
[8] 孙丛丛,王致杰,陈丽娟,等. 基于MATLAB的电力系统故障仿真与检测方法研究[J]. 电力学报, 2016,31(1):1-7,62.
[9] 李夏林,刘雅娟,朱武. 基于配电网的复合电压暂降源分类与识别新方法[J]. 电力系统保护与控制,2017, 45(2):131-139.
[10] 黄南天,袁翀,张卫辉,等. 采用最优多分辨率快速S变换的电能质量分析[J]. 仪器仪表学报, 2015, 36(10):2174-2183.
[11] 金智,尹柏强. 基于广义S变换的高斯领域时频滤波方法[J]. 电子测量与仪器学报,2015, 29(1):124-131.
[12] 杨万清,姜学朴,刘冰. 基于广义S变换和PSO-ELM的电能质量扰动信号识别[J].电力电容器与无功补偿, 2017,38(2):129-134,140.
[13] WANG Q, ZHANG Y S, LIU H W, et al. A novel interference detection method of STAP based on simplified TT transform [J]. Mathematical Problems in Engineering, 2017(2):1-9.
[14] 康兵,康逸群,钟鑫. TT变换及其对角线在暂态电能质量现象识别中的应用[J].陕西电力,2015, 43(12):43-47,56.
[15] JASHFAR S, ESMAEILI S, ZAREIANJAHROMI M. Classification of power quality disturbances using S-transformand TT-transform based on the artificial neural network[J]. Turkish Journal of Electrical Engineering & Computer Sciences, 2014, 21(6):1528-1538.