Product name: Partial discharge detector

Transcription

1 Product name: Partial discharge detector PD detector is mainly used in power transformer, HV mutual inductor, thunder arrester, HV switch, HV XLPE cables, ect. Trough PD detector, product quality can be judged. It is used together with AC voltage test system. Operation conditions Altitude Temperature 1000 m -5 o C~+ 35 o C Relative humidity of HV parts (non condensing) 90 % Operation temperature of electric parts 10 o C~+ 40 o C Relative humidity of electric parts (Non condensing) 80 % no dust in operation area Please refer to attachment if more details are needed. Website: jt.com E mail: dielec@jz jt.com 1

2 JFD-series digital type PD detector Partial discharge test is main test item in power equipment insulation.. Partial discharge level is an important parameter to judge power equipment. The equipment is designed with module function. Modules can be reduced or increased based on customer requirement. The module structure is easy to maintain and upgrade. The instruments adopt present computer hardware processing system, and American National Instrument high speed and high precision assemble card. It adopt digital filter and signal processing to analyze PD signals. The instrument is designed according to IEC standard requirement. To complete partial discharge test, following components are required: coupling impedance unit Calibration pulse generator Work theory: The test method is pulse current method. When tested object Ca generates a partial discharge, two sides of Ca will generate a timely changing voltage Δu, through coupling capacitor Ck to impedance Zm. Pulse current will generate. Assemble the pulse voltage generated by pulse current, amplify it and display it, nominal PD can be tested. PD signal is very short pulse calculated by ns, the voltage tested is within range of μv. For instance, if 0.1 pc 50ns PD signal, through a equivalent 50 ohm impedance unit coupling, the corresponding amplitude is around 100μV. Considering the environment noise might exceed this amplitude, so PD test shall be done inside shielding room. Amplifier inside JFD series can amplify PD pulse and quantify it to nominal discharge. To quantify discharge, pulse generator shall be used for calibration. The instrument adopt computer control, and records voltage when PD happens, for further analyze. Website: jt.com E mail: dielec@jz jt.com 2

3 Theory drawing of PD detector Component: PD module with filer Lower noise sound band front amplifier Attenuation unit, -4 db attenuation step length, attenuation provided to 96 bb HV module Variable gain amplifier(0/20/40/60db) to suit wide range Location unit High speed wide band amplifier(variable gain 10/20/40dB); A/D module High speed A/D:8 digits 50MHz sample rate(upgradeable to 12 digits 100MHz); Low speed A/D:16 digits 250KHz sample rate Components parameter: Calibration charge is generated by pulse (amplitude known) injection to 100pF capacitor. 10mV step voltage represents 1 pc discharge. The rising time of step voltage is shorter than 50 ns. test frequency range: 50/60Hz(30Hz-1Khz optional); Low noise front amplifier Max gain: 80dB; 0-92dB(4dB step length); Attenuator precision: < +/-1%; Website: jt.com E mail: dielec@jz jt.com 3

4 System noise <15uV; Frequency band range: 5Khz-420Khz(hardware)/software filter can be attached; Input impedance: 300 Ohm. PD assemble Test sensitivity: < 0.02pC( load capacitance load capacitance 50pF); Pulse resolution time: < 10uS; Max input pulse voltage amplitude: 100V; Linearity: < +/-1%; Sampling depth of each channel: 32M; Resolution: 8bit±1/2LSB; Max sample speed: 50Mhz(upgradeable to100mhz); Synchronization method: inner triggering outer triggering and manual; Time window: 0~360 multiple window. Voltage assemble Input impedance: 1M Ohm; Resolution: 14bit±1/2LSB; Precision: < +/- 1%; Input max peak voltage: 100V; Max frequency: 1Khz; Display method: effective value; peak value: 2; Fault location (optional) 2/5/10;range expandable Equivalent band width: 40Mh (2 times gain) Sampling speed: 50Mhz(upgradeable to 100Mhz); Website: jt.com E mail: dielec@jz jt.com 4

5 Technical features: FFT real time analyze PD waveform can be real-time displayed. PD frequency band range can be set Digital filter Equipment can set digital filter frequency band, including upper and lower limit frequency band Display function Display voltage waveform and PD waveform (ellipse, sine wave); display present PD value and historic PD peak value, average value. Report data saving function, data analyze, multiple analyze function (historic distribution, 3- D drawing analyze) Easy operation Auto gain regulation, no need of human interference Min test charge<0.1pc; Relatable input attenuation: 0-96dB,step length: 4dB; Pulse resolution time: <2us; Frequency band range: 5KHz-450KHz; Computer measure, control, display and analyze PD fault location function (optional) Power supply: 220V/50Hz; Hardware technical parameters PD module 0-96dB motional range,each 4dB gear Noise below10uv; Band width5khz-450khz; Linearity error below 10%; Measure range pulse low repeativity error below 10%; Website: jt.com E mail: dielec@jz jt.com 5

6 Input impedance 300 ohm Max input pulse voltage amplitude 100V; Sampling precision: 8bit±1/2LSB(upgradeable); HV module 0/20/40/60dB range amplifying; Tested frequency to 1KHz; Input impedance: 1MOhm; Input max peak voltage: 100V; Sampling precision16bit±1/2lsb; Sampling ratio max: 250kS/s; Precision better than 1%; Location module (optional) 10/20/40dB range amplifying; 40dB amplifying, band width above or equals 2Mhz; Time accuracy 20ns(sampling rate 50Mhz)upgradable; Computer unit Computer main board, Intel double core processor, 2 G memory, 320 G hard disk, 10.4 feet LCD screen, DVD recorder, outer USB connector, internet and VGA connector. JFD-2010(4)digital PD detector (computer and PD as a whole) Website: jt.com E mail: dielec@jz jt.com 6

7 2.4.1 JFD-2010(4) computer and PD as a whole front view Figure JFD-2010(4) computer PD as a whole liquid crystal display 2- DVD drive 4- USB#1 5- power indication lamp 6- hardware indication lamp 7- computer start button 8- power input #1 9- computer power switch 10- power input #2 11- computer power fan 12- grounding pipe 13- USB#3 14- USB#4 15- internet inlet 16- VGA 17- cabinet vent#1 18- cabinet wind vent#2 19- board#1 20- HV input module 21- PD input module 22- location input module 23- board #2 Website: jt.com E mail: dielec@jz jt.com 7

8 JFD-2010 digital PD detector (with separate computer) Figure JFD-2010 front view Figure JFD-2010 back view 1- Power switch 2- HV input module 3- PD input module 4- Location input module(optional) 5- Grounding pipe 6- DAQ input terminal 7- USB 8- Power connector Basic function: PD calibration and test system parameter setting PD data memory PD parameter calibration PD location (optional) soft panel function Website: jt.com E mail: dielec@jz jt.com 8

9 Note: the above can be changed as the version upgraded in the future Software start introduction: Click PD detector fast entry button, and start the software as to figure in Windows PD fast entry button Operate the customer logging procedure as to below 图 用户登陆界面 Choose customer name, input code, and choose language, click logging button and enter the maininterface as to figure Main interface Website: jt.com E mail: dielec@jz jt.com 9

10 Enter main interface as to figure 3.4.1: Main interface PD waveform display PD Sine wave horizontal axle is phase value, and vertical axle is PD value PD ellipse wave Website: jt.com E mail: dielec@jz jt.com 10

11 Window adding function System can add window, with unlimited numbers. Click add or delete button, and window can be added or deleted. Click add, and system has dialogue window, input upper and lower limit, click confirm. If click adding window content display, then added window content can be seen, with red mark. Assistance drawing display a) FFT analyze display Website: jt.com E mail: dielec@jz jt.com 11

12 The frequency drawing of PD input signal is for analysis b) Q(U) curve Display PD and voltage relation. When voltage peak value is set at U function setting panel, system will auto describe voltage rising and voltage lowering curve. c) Historic curve Display PD and voltage changing as to time Status Website: jt.com E mail: dielec@jz jt.com 12

13 As to drawing: Three statuses in total Test status: before test, in waiting, after test started, in testing Calibration status indication: before calibration, uncalibrated, after calibration, calibrated. JFD-2 Digital PD Detector(with cable fault location) The PD detector is mainly composed by oscillograph with amplifier. Technical Features: PD test range: 0~145pC Test sensitivity: 1% PD resolution: 8 bit pulse signal PD phase resolution: 0.35 o Sample precision: better than 1% Input channel: 2 Amplifier range: 12 gears 5dB Amplifier frequency range: 100Hz~5MHz JFD-2 PD amplifier filter setting: lower channel 20,30,50,60,80kHz Higher channel:100,200,300,400,500khz Inner calibration pulse generator: square wave outside line 70nS, wave tail: 210~200μS 1% of cable total length(±2 M, when cable length is above 30 M) Voltage range: 0~299kV peak value or effective value Voltage measure resolution: 8 bit pulse signal Voltage measure precision: better than 0.5% Sine/line Data processing: with RS 232 output terminal, connected with computer with above terminal. With software by our company, filing, measure, analysis, window, and help functions can be Website: jt.com E mail: dielec@jz jt.com 13

14 realized. JFD-2010(3) JFD-2010(4) JFD-2010(5) Website: jt.com E mail: dielec@jz jt.com 14