Phóng điện cục bộ (PD Partial Discharge) là hiện tượng phóng điện một phần nhỏ trong vật liệu cách điện của các thiết bị trung và cao thế, là tín hiệu nhận biết của hư hỏng lớp cách điện. PD là kết quả của sự phá huỷ về điện được hình thành do có các khe hở không khí bên trong lớp cách điện, là hiện tượng đánh thủng điện môi cục bộ của một bộ phận nhỏ trong hệ thống cách điện rắn hoặc lỏng dưới tác động của điện áp cao. Hướng dẫn máy đo điện cục bộ Pdetector hãng PDMT, giúp sử dụng máy hiệu quả, phòng ngừa các sự cố về điện, chuẩn đóng các nguy cơ cho thiết bị điện, cáp ngầm, máy biến áp, tủ điện.
Solutions for Condition-Based Maintenance PDetector Handheld Partial Discharge Detectors The Future of OLPD V 1.1 May 2017 PMDT Proprietary Contents About PMDT PM DT PDetector Applications PDetector Kits, Data, and Software How to Use PDetector Partial Discharge Cases Key Technologies for PD Detection & Location PMDT PMDT Proprietary Proprietary About PMDT Headquarters: Missions: Experiences: Users: For the safety of power system operation PM DT Silicon Valley, San Jose CA, USA Have tested more than 20,000 units of high voltage electrical equipment in hundreds and thousands of substations for global electric utilities as well as industrial end users during the last 20 years Utilities Industrial power users MV & HV Equipment manufacturers Electrical Contractors and Service Companies PMDT Proprietary About PMDT "The power industry's most advanced Online Partial Discharge test equipment and services." PM DT Over 20 years of ongoing research and development , we manufacture a complete spectrum of diagnostic and monitoring systems for MV and HV power substations Our manufacturing facility in the heart of Silicon Valley provides local access to high quality American-made circuit boards and components We provide patented, reliable and robust equipment with state-of-the-art capabilities for insulation testing of energized power equipment Certifications: ISO 9001:2008, UL certification, and CE certification PMDT Proprietary USA and Global Clients Electric Utilities Power Industry Manufacturing PM DT Electronics Metals & Metallurgy Oil & Gas Chemical Commercial Buildings PMDT Proprietary PM DT PMDT Across The Globe Headquarters Headquarters Asia Branch Office Branch Offices Representatives PMDT PMDT Proprietary Proprietary PM DT Global Exhibitions 2016 USA PowerTest Expo 2016 France CIGRE Expo 2015 Germany Hannover Messe 2015 USA IEEE DEIS EIC Conference 2014 USA DistribuTECH Expo 2014 Brazil ENIE Expo PMDT Proprietary PM DT International Trainings & Seminars 2015 Korea & Philippines Reps’ Training 2016 IEEE Seminar in Hong Kong 2015 Vietnam, Thailand, Hong Kong Reps’ Training 2016 Seminar for Vietnam Utility 2014 Indonesia & Malaysia Reps’ Training 2014 Seminar for Bangladesh Utility PMDT Proprietary PM DT Global Field Testing in USA PMDT Proprietary PM DT Global Field Testing in USA PMDT Proprietary How to Use PDetector PM DT Power Cable PMDT PMDT Proprietary Proprietary Partial Discharge Cases PM DT Floating Electrode MV Switchgear: Bus Bar Bushing GIS: Joints Transformer: Bushing PMDT PMDT Proprietary Proprietary Partial Discharge Cases PM DT Void GIS: Basin-type Insulator PMDT PMDT Proprietary Proprietary Partial Discharge Cases PM DT Surface Power Cables Switchgear: Contact of CB PMDT PMDT Proprietary Proprietary Partial Discharge Cases PM DT Corona GIS: Insulator Support Part PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location TEV AE Ultrasonic HFCT A Combination of Acoustic-Electric Technology Five-in-One PM DT UHF Compares the multiple types of signals Excludes the disturbance signals Determines the PD type Locates the PD accurately PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location Excludes the Disturbance Signals Selects the right time or shut down the disturbance source PM DT Equips a proper wave filter to filter the disturbance signals of a certain frequency Analyzes the correlation between the detected signals and sinusoidal power phase If there is no correlation, it should mostly be disturbance signals; If there is correlation, it might be PD or disturbance signals from the power system, such as light, air conditioner, meter cabinet, and second circuit Location method After analyzing the frequency content, conduct a simple location and analysis through Time Difference Method to check whether the signal comes from inside of the electrical equipment or the external environment PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location PM DT Time Difference Method PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location 3D Localization Method PM DT PD Signal Source P2 P1 UHF Sensor A A’’ P3 A’ Ground UHF Sensor B B’ B’’ PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location Phase Location PM DT Employs HFCT method to detect the ground strap/body of the adjacent three phases of the power cables The signals of the defected phase have larger amplitude and o pposite phase position, in comparison to the other two phases PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location Determines the type of the PD Typical PD Characteristic Spectrums Particle Floating Electrode PM DT Corona Surface Void PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location Type of Signals Characteristics Void PM DT The discharge signals have obvious symmetry between the positive and negative half cycles of a single frequency cycle There are a larger quantity of discharge pulses Corona There are only one bunch of discharge signals in a single frequency cycle The discharge signals are quite dense There are few discharge signals in each frequency cycle The Floating Electrode signals are quite intermittent, the amplitude are usually bigger and stable, and have high correlation with sinusoidal phase PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location Type of Signals Mobile Phone There are few discrete discharge signals They are quite PM DT Particle Characteristics random and have low correlation with sinusoidal phase The frequency of the pulses are usually between 2.2～217 Hz and the width are usually 0.57 ms Lighting Similar to the floating electrode signals, however the amplitude is not stable and changes greatly Electronic fence The repetition rate of the pulses is of seconds It displays as a series of pulse signals when extending to 20us PMDT PMDT Proprietary Proprietary Key Technologies for PD Detection & Location Determines the severity PM DT Amplitude Position The type of the PD Maintenance Plans Pay attention or Repair Immediately PMDT PMDT Proprietary Proprietary USA Headquarters 6840 Via del Oro, Suite 150 San Jose, CA 95119, USA P: +1 (408) 972-5588 F: +1 (408) 972-5678 E: sales@powermdt.com W: www.powermdt.com PMDT Proprietary