电缆局放检测用柔性压电超声传感器的灵敏度优化  

Sensitivity Optimization of Flexible Piezoelectric Ultrasonic Sensor for Cable Partial Discharge Detection

作　　者：袁燕岭 高岭 张占新[1] 赵一明 颜育 吴明[3] 钟力生[3] YUAN Yanling;GAO Ling;ZHANG Zhanxin;ZHAO Yiming;YAN Yu;WU Ming;ZHONG Lisheng(Chengde Power Supply Company,State Grid Jibei Electric Power Co.,Ltd.,Chengde 067000,China;Tangshan Power Supply Company,State Grid Jibei Electric Power Co.,Ltd.,Tangshan 063000,China;State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]国网冀北电力有限公司承德供电公司,承德067000 [2]国网冀北电力有限公司唐山供电公司,唐山063000 [3]西安交通大学电工材料电气绝缘全国重点实验室,西安710049

出　　处：《高电压技术》2025年第2期652-659,共8页High Voltage Engineering

基　　金：国家自然科学基金(52407026)。

摘　　要：传统压电陶瓷超声传感器与电缆表面之间存在声学界面不匹配问题,而柔性压电超声传感器能够克服这一缺点、实现电缆局部放电超声信号的检测。然而持续提高柔性压电超声传感器的灵敏度,进一步降低其对超声信号的检出极限,是其走向实际应用的关键。为实现这一目标,该文从柔性压电超声传感器的核心敏感材料(压电薄膜)的优化设计出发,研究了厚度对Pb(Zr_(0.52),Ti_(0.48))O_(3)(PZT)压电薄膜材料综合性能及其所制备的传感器灵敏度的影响。研究发现,受界面死层的影响,厚度约为1.2μm的PZT压电薄膜相较于厚度约为0.8μm、1.0μm和1.6μm的薄膜具有更大比例的(100)晶粒择优取向和更高的剩余极化,表现出最高的压电系数,更具备应用潜力。利用该厚度的PZT压电薄膜制备了柔性压电超声传感器,并用其检测在110 k V真型电缆上传播的由自动笔铅芯断裂产生的超声信号,计算得到该超声信号在交联聚乙烯绝缘层中的衰减系数为3.74 dB/m。该研究提供了一种利用压电薄膜厚度优化柔性压电超声传感器灵敏度的方法,为进一步推进柔性压电超声传感器在电缆等电力设备领域的应用提供了实验和理论基础。The traditional piezoelectric ceramic ultrasonic sensors face the challenge of acoustic impedance mismatch at the interface with cable surfaces,whereas flexible piezoelectric ultrasonic sensors overcome this limitation and enable the detection of ultrasonic signals from partial discharge in cables.However,continuously enhancing the sensitivity of flexi-ble piezoelectric ultrasonic sensors and further reducing their detection limits for ultrasonic signals are critical for their practical application.To achieve this goal,we focus on the optimization design of the sensitive material,namely,piezoe-lectric thin films,in flexible piezoelectric ultrasonic sensors,and investigate the influences of thickness on the comprehensive performance of Pb(Zr_(0.52),Ti_(0.48))O_(3)(PZT)piezoelectric thin films and the sensitivity of the sensors fabri-cated with these films.The findings reveal that,due to the effect of interfacial dead layers,PZT piezoelectric thin films with a thickness of 1.2μm exhibit a higher proportion of(100)-oriented grains and greater remnant polarization compared to films with thicknesses of 0.8μm,1.0μm,and 1.6μm,thus the PZT piezoelectric thin films possess the highest piezoe-lectric coefficient,highlighting the greater potential for practical applications.Flexible piezoelectric ultrasonic sensors fabricated using the 1.2μm-thick PZT piezoelectric thin film were employed to detect ultrasonic signals generated by the fracture of mechanical pencil leads propagating in a 110 kV full-scale cable.The attenuation coefficient of the ultrasonic signal in the cross-linked polyethylene insulation layer was calculated to be 3.74 dB/m.This study provides a method to enhance the sensitivity of flexible piezoelectric ultrasonic sensors by optimizing the thickness of piezoelectric thin films,and offers both experimental and theoretical foundations for advancing the application of flexible piezoelectric ul-trasonic sensors in cables and other electrical power equipment.

关 键 词：电力电缆 局部放电 柔性压电传感器 超声检测 PZT薄膜 

分 类 号：TP2[自动化与计算机技术—检测技术与自动化装置]