350kV 8000KVA series resonant cable test system

Technical Specification：XZL-8000KVA/350KV AC Resonant Test System Customer: Elsewedy Cables-Egypt Page 1total 24

AC Voltage Withstand & Partial Discharge

Complete Test Equipment For

220kV & Lower Rubber Plastic Cable & XLPE Cable

Routine Test

Technical Specification

(XZL-8000/350)

Y a n g z h o u P o w e r E l e c t r i c C o . , L t d .

Design Specification

This set of AC inductance tunable cascade resonant test equipment is mainly for testing and

inspecting cables and capacitors of 220kV and lower voltage, ensuring the 220kV large cross

section cables with reel(cross section area ≥2500mm2, length of the whole reel≥600m) meet

the voltage withstand and partial discharge test requirements of IEC60840-1997 and national

standard GZ/T 18890-2002.

Steel shell (I) cable partial discharge testing system (350kV 7000kVA 20A) sold

to India for cables of 220kV and lower voltage. It have been running

successfully.


PQ test system provided for Wuhan High Voltage Research Institute for testing cables of 220kV and

lower voltage. It was the first one of the same kind in China.

Short sample partial discharge testing system (1200kV 7200kVA) provided for China National Cable and

Wire Quality Supervision and Inspection Center (Shanghai Electric Cable Research Institute) in 2010 for

testing cables of 500kV and lower voltage. It is now running in the SECRI MV lab.

PQ test system (700kV 14000kVA) provided for China National Cable and Wire Quality Supervision and

Inspection Center (Shanghai Electric Cable Research Institute, SECRI) in 2010 for testing cables of 500kV

and lower voltage. It is now running in the SECRI outdoor PQ center. It is cable of running continuously.

Siait Cable Co.,

Ltd. 120kV/1200kVA-40kV/800kVA

TBEA(Sichuan Province)120kV/50kV/1200kVA

Showing in the above two photos are PD testing system for cables of 35kV and lower voltage provided

for Siait Cable Co., Ltd. and Tebian Electric Apparatus Co., Ltd. (TEBA) in 2011. We have provided quite a

few similar cable PD testing system to some famous companies in China such as Siait Cable Co., Ltd.,

TEBA, Hebei New Baofeng Wire & Cable Co.,Ltd, Jiangsu shangshang Cable Group etc.

220kV and lower voltage cable partial discharge testing system (insulated cylinder shell type, 350kV,

12250kVA, 35A) provided for Jiangsu Zhongtian Technology Co.,Ltd. in 2010. It finished the history of

this kind of cable partial discharge test equipment relying on importing form other countries.

1000kV and lower voltage cable partial

discharge testing system (1400kV, 49000kVA,

35A) provided for Hebei New Baofeng Wire &

Cable Co., Ltd in 2011. The picture shows

SECRI doing type test to their equipment

with our two-stage cascade equipment in our

lab. This set of equipment is a landmark in

the cable testing industry in China.


We have just been awarded the bid of 500kV (1000kV) and lower HV cable

accessories partial discharge testing equipment of ANKURA.

AC Voltage Withstand & Partial Discharge Complete Test

Equipment

For 220kV & Lower Rubber Plastic Cable & XLPE Cable

Routine Test

Technical Specification

I. Application Scope

This set of AC inductance tunable cascade resonant test equipment is mainly

for testing and inspecting cables and capacitors of 220kV and lower voltage,

ensuring the 220kV large cross section cables with reel(cross section area

≥2500mm2, length of the whole reel≥600m) meet the voltage withstand and

partial discharge test requirements of IEC60840-1997 and national standard

GZ/T 18890-2002.

II. General Service Condition

Altitude: ＜1000 米

Ambient temperature：－10℃～＋45℃

Relative humidity：＜90％（at 25℃）

Max. daily temperature difference:25℃

Atmospheric pressure：0.1MPa

Atmospheric humidity：11g/m3

Earthquake intensity：≤7 级

Service environment：Indoors

No conducting dust

No fire or explosion hazard

No metal corrosive gas or insulating gas in the lab

Waveform of the supply voltage is actual sine wave, waveform deviation factor <3%

Earth resistance <0.5 with a reliable grounding point

Site background PD level＜3pC

III. Standards

GB10229 Reactor

JB/T9641 Test transformer

GB1094 Power Transformer

GB/T 16927.1 High Voltage Test Technology; First Part Common Test Requirements

GB/T 16927.2 High Voltage Test Technology; Second Part Measurement System

GB7328 Transformer and Reactor Sound level Measurement

GB7354 Partial Discharge Measurement

GB8749 General Technical Requirement for Voltage Regulator

JB/T563 Coupling Capacitors and Capacitor Dividers Ordering Technology

GB/T.311 Insulation Co-ordination of High voltage Transmission and

transformation equipment

GB2536 Transformer Oil

GB 2900 Electrical Terminology

GB4208 Degrees of Protection Provided by Enclosure

IEC 60840

Power cables with extruded insulation and their accessories for rated

voltages above 30 kV (U<(Index)m> = 36 kV) up to 150 kV (U<(Index)m>

= 170 kV) - Test methods and requirements

IEC 62067

Power cables with extruded insulation and their accessories for rated

voltages above 150 kV (Um = 170 kV) up to 500 kV (Um = 550 kV) - Test

methods and requirements

IV. Wiring Diagram of the Main Test Loop

LV Switchgear GGD-0.38

LV Filter LBL-800A/0.6kV

Resonant Reactor XZL-8000kVA/350kV

Exciter Transformer ZB-300kVA/5kV/10kV/20kV

HV Filter LBH-350kV/30A

HV Column Type Regulator TYDZ－300/0.38/0-0.65

AC-2008 Automatic Control System

Safety Discharge Rod

V. Main Technical Parameters

5.1 Integral Performance Parameters

Rated input voltage：0.38kV

Nominal Power：Tap I：8000kVA

Tap II：8000kVA

Tap III：2625kVA

Rated input power：300kVA

Rated input current：789.5A

Rated output voltage：Tap：350kV

Tap II：200kV

Tap III：100kV

Rated output current：Tap I：22.8A

Tap II：40A

Tap III：40A

Phase：single

Service Frequency：50Hz

Total Harmonics Distortion：<3%

Cable inductance tunable range and capacitor loading range：

Tap Ⅰ：48.0H～977H 0.01～0.21μf

Tap Ⅱ：15.9H～318H 0.0318～0.637μf

Tap Ⅲ：7.96H～159H 0.0636～1.27μf

Inductance range deviation：0～+10%

System PD level：＜2pC at 350 kV

Temperature rise requirements: running for one hour with full load and cooling for

one hour, six cycles and temperature rise ≤65k

Voltage withstand requirement：35kV for one hour

Noise level ≤75dB （within the range of 4 m）；

Quality factor：＜ 60；

5.2 LV Switchgear Cabinet

LV switchgear cabinet is mainly for switch on and off the main power supply of the test

loop; it also has the function of over-current and over-voltage protection, ensuring the

test can be conducted safely. Technical parameters are：

Model：GGD-0.38

Raged frequency：50Hz

Rated voltage：0.38kV

Rated current：1200A

Installation：Indoors

Operation voltage：AC220V

Protected by AC contactor and isolating switch.

Main features：easy to install, close operation and remote operation, with the

functions of 安 isolating and switching, over-current and over-voltage protection,

instantaneous trip protection, measuring indication etc.

5.2 Column Type Voltage Regulator

Voltage regulator provides exciter transformer with adjustable AC input voltage from zero

to rated value. It has the advantages of outputting voltage with small total harmonics

distortion, low power consumption, high efficiency and

small spark. It also has the functions of motorized

regulating, zero voltage output, upper limit and lower limit.

Model：TYDZ－300/0.38/0-0.65

Rated capacity：300kVA

Rated input voltage：0.38 kV

Rated input current：789.47A

Rated output voltage：0～0.65kV

Rated output current：461.5A

phase：single phase

rated service frequency：50Hz

Total harmonics distortion：<3%

Regulating type：motorized regulating

Structure feature：column type

Running time：the same as reactor

Short circuit performance：Under the transient state capacity state, when test object in

the test loop discharges and lasts no more than 5 wave period, no thermal damage or

mechanical deformation should happen to the regulator winding group.

5.4 LV Filter

LV filter is between the regulator and exciter transformer and it is mainly for suppressing

the interference of the clutter from power supply within the bandwidth of PD

measurement, improving the sensibility of PD test and reducing the background noise.

It is designed to use passive network, including cascade inductor and parallel capacitor,

“JT” structure, low-pass property, low passband loss, big high-frequency attenuation. Lv

filter to be installed in the regulator cabinet and following are the technical parameters：

Model：LBL-800A/0.6kV

Rated voltage：600V

Rated current：800A

Filter reactor quality factor：＞70

Attenuation characteristics：40KHz～100KHz＞40dB

100KHz～1MHz＞60dB

Insulation level：5kV/1min no abnormal discharge

Running time: the same as resonant reactor

Cooling: natural air cooling

5.5 Exciter Transformer

Exciter transformer provides exciting voltage to HV resonant reactor, isolating the testing

loop and voltage adjusting loop. Its secondary side and HV reactor compose a cascade

resonant loop.

There is instrument coil inside the transformer and the exciting voltage value can be read

through the meters on the control console, and HV current signal can be sent to the

control system through current transformer that installed in the HV earthing loop.

Model：ZB－300

Rated capacity：300kVA

Rated input voltage：0.6kV

Rated output voltage：12kV、7.5kV 5kV

Rated output current：25A、40A、40A

HV switchgear: with 12kV/7.5kV/5kV

motorized discharge free change-over

switchgear；

Measuring voltage: 100V

Phase: single

Rated service frequency：50Hz

Total harmonics distortion：<3%

Temperature rise：65K

Cooling type：ONAN

Insulation level：withstanding for 1 minute at 1.1 times of rated voltage

Running time：the same as reactor

5.6 HV reactor

XZL-8000/350/200/100 reactors as

the critical part in the system form

series resonant circuit together with

load capacitance. When the induced

reactance of reactors matches the

capacitive reactance of cables, the

system gets into resonant condition.

The reactor is equipped with

self-coupling tap which could make the output voltage reach up to 350KV in no-load

condition.

Parameters for single reactor：

Model: XZL－8000/350/200/100

Structure: metal tank, oil-immersed, natural cooling, output through capacitive HV

bushing which is led until within the shielding room.

Rated capacity: tap I: 8000kVA

tap II: 8000kVA

tap III: 4000kVA

Rated output voltage: tap I: 350kV

tap II: 200 kV

tap III: 100kV

Rated output current: tap I: 22.8A

tap II: 40A

tap II: 40A

Phase: single

Rated working frequency: 50Hz

Waveform distortion rate: <3%

Temperature rise: under full load, ON Ih OFF 1h as one duty cycle, capable of 6

cycles; temperature rise≤65K

Quality factor: >45

Noise level: <75dB

Inductance regulation: motor-driven, stepless regulation

Cooling approach: ONAN

PD of the reactors: at 280 kV ＜5pC, at 350 kV ＜10pC,

PD with HV impedance system: at 350 kV ＜2pC,

Voltage withstanding: at 350kV running for 1h

Running time: under rated capacity, ON Ih OFF 1h as one duty cycle, capable of 6

cycles

HV switches: motor-driven, no discharge, HV change-over switch, could output

voltage of 350kV/200kV/100kV

Design description:

The reactor main part is fixed in frame. Cushion is used at the contact to oil tank. fixed

inductance is regulated through motor which is installed on the lid.

Shielding on top of porcelain bushing is round.

Inner structure:

5.7HV Filter（including capacitive voltage divider, coupling capacitor and

isolation impedance）

Model: LBH-350

Rated voltage: 350kV

Rated frequency: 50Hz

Rated capacitance: 6nF +6nF

Measuring precision: ≤1％

Dielectric loss: ≤0.4%

Attenuation:15kHz～300kHz≥40dB

Insulation level: 1.1 times of rated voltage

withstand for 1min

Chassis: stable enough, could keep balance on

uneven floor, easy to assemble and disassemble, with wheels for movement

Capacitive voltage divider could be also used as coupling capacitor during PD

measurement.

Running time: as reactor

Principle:

Commonly very small PD is required during tests. Then a HV audio frequency interference filter

is needed between the HV reactor and the test object to ensure small PD level measurement.

The HV filter is composed of L-C-L-C combination. L stands for isolation impedance, forming π

type filter together with the capacitance C. There is measuring capacitance at bottom of the first

capacitor which functions as well to measure output voltage of the voltage divider and the

resonant system. The second capacitor is actually a coupling capacitor, connected with PD

detector through inspecting impedance, thus to allow PD signals measurement in the meantime.

Additionally, the two capacitors function as basic load of the system, which is good for small

load and sample tests.

HV Capacitors

Model:TAWF-6000/350

Quantity：1

Rated voltage: 350 kV

Rated capacitance: 6nF

Rated power: 50 Hz

Dividing ratio: 10000:1

PD: at rated voltage ＜2pc,

Structure: oil-immersed, moveable, composed of top shielding, main part, chassis, LV arm,

etc.

Model: ORF-6000/350

Quantity: 1

Rated voltage: 350 kV

Rated capacitance: 6nF

Rated frequency: 50 Hz

HV capacitors act basic load. The total capacitance of the two capacitors make the system

run normally on no-load condition. That is to say, basic load capacitance is no less than

minimum value of the HV reactor load range.

Isolation impedance

Model: LS 350-60/30

Quantity: 2

Rated current: 30A

Running time: continuous running

Rated inductance: approx. 60Mh

5.8 XZL-2008 Series Resonant Test

Control System

Control system is center of the complete PD

test system, located inside the control room. All

control operations are accomplished through the

control system. All switches, lamps, contactors

and circuit boards are selected from products

made by manufactures of the first class home or

abroad.

General description

The control system for series resonant test device is modified on basis of that of traditional transformer

voltage withstand test device. The control system makes advantages of modern computer for the intelligent

automatic voltage control of series resonant system. Console with fully functional and simple user interface,

all control components are clear at a glance. You can easily use the control system for all kinds of voltage

withstand tests you need, such as sample acceptance voltage withstand test, step by step voltage

withstand test. When you use this resonance test system, you will find the past cumbersome test

operations are replaced with a few simple mouse clicks.

Functions

Hardware Functions

The resonant control system is designed from the standpoint of safety of using. In addition to

various voltage withstand test functions, it also has a variety of protective features, including

operation security of equipment, test operator safety protection etc. Control system has the

breakdown flashover protection function which minimizes the extent of damage from the

breakdown of the sample, to provide samples of prototype as complete as possible for the

analysis of the failed sample.

One of the main functions of Junction Box is the ON/OFF of the voltage regulator, voltage

regulation and state detection, etc., the other main function is to drive reactor core gap to

regulate motor and high-voltage side state detection. Junction boxes are equipped with

equipment provided by ABB and Mitsubishi products to ensure the reliability of the test control

system, rapidity and accuracy.

Main function of protection interface module is to restrain and absorb the transient over-voltage

from junction box of series resonant test system, to ensure the safe operation of the console

and operator safety.

The control device measures all the parameters of the resonant test system and also all the

movements of the control system. As measuring equipment, the control device is consisted of

the equipment modules from world-renowned manufacturers to ensure the long-term stability of

equipment operation. Data acquisition unit uses AD conversion of 14-bit precision to ensure the

accuracy of test voltage. Flashover detection unit shows signal in the test sample flashover

moments, direct action triggers circuit breakers to protect the integrity of test samples. At the

same time, flashover detection unit can detect the flashover transient voltage waveform polarity

and amplitude of test samples.

Software functions

The system adopts Windows 2000 operating system which ensures long-term stability of the

control system operations.

The program has friendly human-computer interface which allows users to control the test

system intuitively. User can do some simple voltage withstand test manually or automatically,

and can also set the timer to do the voltage withstand test at a certain time. In some areas of the

interface, they shows different colors according to different working status of the resonant test

system which has great help on reminding operations for user. The software has over-voltage,

over-current protection function, when the test voltage exceeds the protective setting value by

user’s mistakes or power supply fault, the system will decrease the voltage automatically or

directly break the power supply to protect the safety of test samples.

The main test parameters shows on the programming interface: system output voltage,

resonance status, system output current, output voltage of exciter transformer, working status of

voltage regulator, test waveform curve and all kinds of main working status.

The software “flow control” has the function of sequential operation which brings convenience

for users. User can set series of voltage values, voltage withstand time, change speed of

voltage, and then the “flow control” will perform the sequence of operation automatically. User

can also set the test starting voltage, step voltage, change speed of voltage and voltage

withstand time to do the step by step voltage withstand test.

Test waveform curve window displays the voltage change process of the test sample, by which

user can do analysis on the test intuitively. The test report can be generated automatically by

the control system according to waveform curve which improves user’s working efficiency. All

the test data will automatically keep the record in the hardware of the computer, user can check

the record at any time.

The control system will update and keep the alternating voltage and current waveform of the

test, it lasts for 20s. When the test sample flashover occurs, the control system will stop

updating and keep all kinds of original data 20s before flashover. User can check the change of

alternating voltage and current 20s before flashover which provides direct waveform parameter

for the further research.

Technical specifications

Console measurement accuracy

Name Sampling precision Note

System output voltage 14 bit

System output current 14 bit

Exciter transformer output voltage 14 bit

Voltage regulator output voltage 14 bit

Voltage regulator Output Current 14 bit

Flashover protection time

System operating time ≤ 10ms

a, Console input power

Name Specification Note

Voltage 230V ± 10%

Capacity 400VA

Frequency 50/60Hz

Protective tube 5A

b, Console inside supply


+24V 5A

+15V 1.5A

-15V 1.5A

+5V 3A

c, Console input and output switch


input 24A DC

output 24A DC

d, Console input and output analog


input 0~7V AC

input 0~10V DC

output 0~10V DC

Matching Peak Voltmeter

Peak voltmeter is used in AC voltage withstanding test to measure the testing voltage and RMS.

Requirements for the peak voltmeter:

Input voltage measuring range: 500V, for peak voltage / 2 or RMS

This is the actual input voltage for the meter. Input voltage=testing voltage/dividing ratio

Peak reappearance B: peak/RMS

Displays：

Voltage display: takes 4 and half bit digital meter, directly display RMS or peak/ 2 of the

testing voltage. Reading is in KV.

Dividing ratio can be set with DIP switch: the switch contains 4 digits, thus the dividing ratio

could be up to 9999. Before tests, set this switch to select suitable dividing ratio to get more

precise measurement.

Precision not less than Grade 0.5.

Hold of the over voltage at the discharge instant.

5.9 Safety Discharge Rod

During voltage withstanding test, if the cable is breakdown, or when testing on one stand of a

triplex cable with the rest two phases suspended, there may be residual or induced charge on

cable. To ensure safety of personnel, the system is equipped with a safety discharge rod. With

this rod discharges the cable completely when test is over, thus possible hazard will be

removed.

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350kV 8000KVA series resonant cable test system