Electrical Tests and Root Cause Analysis of Insulation ...

Electrical Tests and Root Cause Analysis

of Insulation System Faults

Jan Petrik on behalf of WP11, contributions from:

A. Foussat, L. Grand Clement, F. Evrard, J.B. Neyret,

F.O. Pincot,J.C. Perez, S. Izquierdo Bermudez, F.

Mangiarotti, G. Willering, G. Ninet, C. Scheuerlein, B.J

Katzer, H. Prin, F. Savary, A. Milanese, F. Wolf

Review of quench protection and electrical tests of 11 T dipole – 11/01/2019

Presentation Outline

2Jan Petrik, 11/01/2019

Electrical tests overview

Hi-Pot measurements and test results

Fault investigation and extended Hi-Pot tests

Insulation system analysis

Ongoing tests

Summary


3Jan Petrik, 11/01/2019





Ongoing tests

Summary

Electrical tests during coil fabrication

4Jan Petrik, 11/01/2019

Highlighted test are acceptance test

Electrical Tests - Coil

5

-100

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0 0.002 0.004 0.006 0.008 0.01I (A

)

U (

V)

Time (s)

Coil Discharge

Coil, U(t) Coil, i(t)

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1 10 100 1000 10000 100000

Coil Z ; Phase

Z PH

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1 10 100 1000 10000 100000

Coil Ls ; Q

Ls Q

Jan Petrik, 11/01/2019

-200

0

200

400

600

-0.05 0 0.05 0.1 0.15 0.2 0.25U

(V

)Time (s)

QHs Discharge

QH Left QH Right

Electrical Tests

Hi-Pot testing on long coils

6

Impregnated Coil test Collared Coil test

QH test voltage reduced later revision(0.2) of EDMS1995595 to 3200V


https://edms.cern.ch/document/1995595

Repeatability of High Voltage Testing

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IRI[G

Ω]

IR vs. Test Voltage and Time, 0 - 120s

500V, 10 min,cables on stands -guard




3

3.5

4

4.5

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5.5

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

IR[G

Ohm

]

# Measurements

Dwell Time Effect on IR(500V/30s)

30s Dwell Time

120s Dwell Time

18%

488% @ 3kV


Observations on IR Testing


Test parameters (voltage, duration, ramps) are important!

They need to be stated with IR value

Different test conditions = IR values are not comparable

In case of successive tests, dwell time is important (min 4x*)

High value IR measurements are sensitive to

Surface leakage

Airflow, temperature, humidity…

More information in engineering report: EDMS2053320

* “A Stitch in time” A complete guide to electrical

insulation testing, Megger

https://edms.cern.ch/ui/#!master/navigator/document?D:100244938:100244938:subDocs


9Jan Petrik, 11/01/2019





Ongoing tests

Summary

Short Models

10

All short models tested at 1kV

To detect major issues, yet not big enough to

damage the coil

Default test value for all magnets (not related to

design value/design independent),

SP102 (external QH) tested after cold test

8.5kV/30s - 32.5 GΩ

Coil #110 (impregnated QH) not subjected to cold

6kV/30s - 9.5 GΩ

All but SP107 and SP109 have different insulation

system compared to production coilJan Petrik, 11/01/2019

Long Coils

11

Long coil data extracted and compiled from test files

Including test parameters

EDMS 2032106 (link)

Continuously updated

Test value tracking across the production

Comparison among different coil PN

Graphical representation



12

11T Prototype

HCMBH_C005-

CR00001

HCMBH_C005-

CR00002

HCMBH_C005-

CR00004

HCMBH_C005-

CR00005

HCMBH_C005-

CR00006

HCMBH_C005-

CR00007

HCMBH_C005-

01CU0001

HCMBH_C005-

01000001

HCMBH_C005-

01000002

HCMBH_C005-

01000003

HCMBH_C005-

01000005

500v, 60" 7.88 6.42 2.21 1.86 1.45 1.75 11.60 1.64 1.71 1.83 2.26

3000V, 2 mins 5.60 5.59 4.40 9.35 4.21 10.89 7.30 7.97 9.04 10.82 14.67

7.88

6.42

2.211.86

1.451.75

11.60

1.64 1.71 1.832.26

5.60 5.59

4.40

9.35

4.21

10.89

7.307.97

9.04

10.82

14.67

0

2

4

6

8

10

12

14

16In

su

lati

on

res

ista

nc

e [

GO

hm

s]

# coils

RI Value, QH/COIL - AFTER IMPREGNATION

Production Coils

Hybrid Prototype


Issue on QH-coil insulation in 11T prototype

After the failure of power cold test of aperture

AP1 on first 11T MBH001 prototype, the cold

mass has been opened and electrically

reconfigured (to facilitate independent

aperture testing).

During a standard re-commissioning test (test

voltage 2.1kV ), breakdown in insulation

system occurred. Resulting in damaged

insulation with resistance below 1GΩ

requirement.

13Jan Petrik, 11/01/2019


14Jan Petrik, 11/01/2019





Ongoing tests

Summary

Extended Test Program

in QH-Coil Insulation Goal of extended Hi-pot dielectric and discharge tests was to

burn-through insulation defect to facilitate fault

localization on prototype, and reproduce it on other 11T

coils and models

Successive use of MEGGER Burn mode (I leak < 3mA), C-

bank discharges using QPS (6 mF, 50-450V), CDG 7000(2

µF, 500-1000V).

All QH pushed to shorts, individually – either in collared or in

uncollared state.

15Jan Petrik, 11/01/2019

Findings on MBHP001 - CR06-07 Initial insulation resistance in range of ∼ 2-3 GOhms.

Direct shorts provoked in collared coil state was

found in same cross sections on paired coils,

residual resistance of few Ohms.

All in LF strip region

Type of direct short defect created in

extended Hi-pot test on CR07, ( hole

diam 2 mm, dumped E tot > 1kJ)

Short after successive C

bank discharges in CR06

16Short detail after peeling test

Last discharge before

burn through


Extended Hi-pot tests overview

17* Note: All coils but SP107 used previous turn insulation design before the Nov.2017 change

collaredCold

tested

CR06, CR07

(MBH001)

CR06, CR07

(MBH001)

CR 01 bare (3) Each QH, Hi pot dielectric test +

insulation testBrkd @ 8.5 kV LF- strips

CR 02 bare (3) Each QH, Hi pot dielectric test +

insulation test

Brkd beyond @ 4kV

OK, no brkdN/A

SP106 collared (1)

Each QH, Hi pot dielectric test +

insulation test, then C bank

discharges

Brkd @ 2 KV N/A

#114, #115 bare



discharges

Brkd @ 2.1 kV LF- strips

# 110 bare Brkd @ 6 kV LF- strips

# 201 bare Brkd @ 4kV

surface to traceLF- strips

SP107 collared Left QH, Hi pot dielectric test +

ramp testBrkd @ 2.8kV N/A

collared

bare



discharges

(1) All QHs-coils, Hi pot dielectric test

then individual C bank dischargesBrkd @ 2.1 kV LF- strips

Hi pot dielectric test + C bank

dischargesBrkd from 2 kV LF- strips

locationCoil name *

State of

Hi-pot

tested

coils

History of coils

Hi –pot test sequenceInitial Breakdown

voltage value

Internal QH


Summary of Extended Hi-Pot tests

Both long and short cold tested bare coils show breakdown

voltage on QH-coil insulation of 2kV or larger.

Non cold-tested coils ( independently of collaring

history) show larger breakdown voltage value larger than

4kV (up to factor 4 @ 8.5kV)

Surface autopsy on prototype QHs did not reveal specific

defects, delamination, nor de-bonding

Defects in LF area

We were not able to reproduce damage pattern (to reduce

IR to MΩ in one Hi-Pot test) of 11Tprototype.

18Jan Petrik, 11/01/2019


19Jan Petrik, 11/01/2019





Ongoing tests

Summary


Insulating materials

Mica tape - 80 μm, C shape

S2-Glass braid layer

CTD 101K resin

50 μm (nominal) polyimide film (Kaneka Apical AV)

Dielectric Strength 9.85 kV/50 μm,

No mechanical stress stated

QH backing material

20

Heat treated @ 650°C

100μm @ 5MPa

Polyimide thickness variation C005-CR006

courtesy of M. Crouvizier EN/MME/MM


S2 Glass and Mica

Very brittle

Provides mechanical

spacing

Place for resin to go

21

Coil surface after 650°C heat treatment

SC cable with Mica and glass braid,

picture courtesy of S.I. Bermudez

Jan Petrik, 11/01/2019 22

Impregnated Coil

CTD 101K Insulation system

Datasheet value (link)

500um S2 Glass

No mechanical stress

11T average value of pressure is 50MPa

Thickness of resin not controlled

Integrity is not guaranteed (delamination, cracking)

Jan Petrik, 25/10/2018 23Jan Petrik, 11/01/2019

https://www.ctd-materials.com/wordpress/wp-content/uploads/2014/05/CTD-101K-DS-2014.pdf

Jan Petrik, 11/01/2019 24

Recent Progress and Tests of Radiation Resistant

Impregnation Materials for Nb3Sn Coils

R. Bossert, S. Krave, G. Ambrosio, N. Andreev, G. Chlachidze, A.

Nobrega, I. Novitski, M. Yu and A.V. Zlobin

• 125 μm S2 Glass sleeve

• DOI: 10.1063/1.4860615, 2018

CTD 101K Insulation Under Pressure

Investigation of Alternative Materials for Impregnation

of Nb3Sn Magnets

Deepak R. Chichili, Jay Hoffman, and Alexander V. Zlobin

• 50% overlap of ceramic tape

• insulation thickness 0.250mm per cable

• DOI: 10.1109/TASC.2003.812892, 2003

Extrapolated/estimated breakdown voltage of 10 kV/1mm

Only resin and glass/ ceramic tape (no Polyimide)

Insulation System Imperfections

Jan Petrik, 11/01/2018 25

Coil #106 – cracks in resin

C005-010005 - Delamination along

edge of a new long coil.

Coil was not collared, neither cold

tested

Cross-section pictures of C005-CR006

courtesy of M. Crouvizier EN/MME/MM

C005-010003 – QH trace wrinkles,

probably linked to assembly

procedure (multiple mold opening –

not regular procedure)


Summary of Insulation Materials

Integrity of S2 Glass, Mica and CTD 101K resin

can’t be guaranteed during manufacturing and

commissioning

Although insulation system consist of multiple

layers, there is no redundancy

We rely on 50 μm (nominal value) of polyimide

Dielectric strength/integrity/thickness of the

other layers is not controlled/guaranteed

Our Hi-Pot test results are not in agreement with

polyimide datasheet values26


27Jan Petrik, 11/01/2019





Ongoing tests

Summary

Pressure effects on polyimide dielectric

strength Extracted from QH

Sample size cca 3x4cm

Brkd. voltage test next

Jan Petrik, Felix Wolf, 11/01/2019 28

0

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5 15 25 35 45 55 65 75 85 95 105 115 125 135

% r

ef.

to m

axim

um

IR[T

Ω]

Pressure [MPa]

IR vs Pressure3kV/30s

%

IR

Partial Discharge

Very sensitive measurement that can detect

miniature failures in insulation (bubbles, voids..)

Industry standard test, nondestructive

Good for relative comparison

29

By Wtshymanski at English Wikipedia,

CC BY-SA 3.0

PD Activity on coil #110, left QH from

connection side


https://commons.wikimedia.org/w/index.php?curid=21179289

https://commons.wikimedia.org/w/index.php?curid=21179289

Jan Petrik, 11/01/2019 30

PD Activity on coil #110, left QH from

connection side

Partial Discharge

AC

Filter

PD

DetectorDUT

Quench Heater Insulation Under Compression

Load

Courtesy of Felix Wolf

Cable 18-stack

Quench heater on polyimide film

Impregnation

V

Applied load

Press tool

Quench heater (~30µm) on polyimide film (50µm)

Reacted cable 18-stack

Press support

Impregnation (CTD-101K)

Multilayer insulation to ground (8x125µm)

Multilayer insulation

15

.6 m

m

26.45 mm

Study of radial load (0-90MPa) effect

on insulation resistance.

QH and SC cable same as 11T

2nd half of January

Quench heater insulation bending test

Courtesy of Felix Wolf

Study of mixed load (compression, shear, bending)

effects on insulation resistance

QH and SC cable same as 11T

End of January

𝑙 =75 mm

𝐹𝐴 𝐹𝐵

𝐹

VQuench heater on polyimide film

Cable 2-stack

Steel bar

3.8

mm

15.4 mm

Multilayer insulation to ground

Multiplayer insulation to ground

Applied Load

Sliding contact

Impregnation (CTD-101K)

Applied Load (0-1000 N)

Paschen conditions test of QH-coils insulation Principles:

In previous impregnated coils, a sound insulation is guaranteed when a

complete encapsulation of all high voltage active parts by solid insulation

ensures a reliable high voltage operation independently of the surrounding

vacuum conditions.

Objective :

to test the reliability of the Quench-coil electrical insulation under all

possible pressure conditions, a so-called Paschen test can be performed.

To reveal a possible influence on breakdown by the level of partial air

pressure

Protocol:

After the pressure was reduced to approx. 0.01 Pa ( 10-4 mbar) to 50000 Pa (

500 mbar) using a stabilization holding time of 30 mins, the pressure was

raised in steps and at the different pressure ratings the DC breakdown

voltage ( leakage current) from heater wires to coil is measured.

Paschen curve – Leakage current

DOI: 10.1109/TASC.2011.2179393

Paschen curve for air Preparations are underway

In cooperation with TE-CRG

Testing starting from 20th Jan.

https://doi.org/10.1109/TASC.2011.2179393

Further planned tests

35

Effect of mechanical pressure on breakdown voltage of

polyimide (TE-MCS-LMF), 2nd half of January

Thermal cycling of collared pack at 77K + insulation

check (TE-MCS-LMF + TE-CRG-CI), early February

Extended QH testing SP109 – firing at increased

current (TE-MSC-TF), see Gerard’s talk

Paschen test in cryostat (TE-MSC-TF) – at 80K,100K,

200K



36Jan Petrik, 11/01/2019





Ongoing tests

Summary

Summary

37

Insulation integrity is tested through the production at

various stages of coil production according to

specifications. QH to coil dielectric tested 3x times, plus

further testing is done during cold-mass assembly

11T prototype QH insulation damage has been

reproduced on both short and long coils

Weakness in LF area, under QH strip

Breakdown voltage is lower for cold tested coils


Summary

38

Integrity of resin and Mica tape can not be

guaranteed over the magnet lifetime

Multiple layers of insulation, yet no redundancy

There is no backup in case of Polyimide failure

More tests are underway to characterize the effect of

contact mechanical pressure, shear strain, partial gas

pressure and temperature on the insulation system


Back up Slides

39Jan Petrik, 11/01/2019

Improvement Suggestions

Possible improvements to our Hi-Pot tests:

Unify test parameters/introduce baseline measurement

for short models, long coils, cold testing

Collect more refined data - individual QH

Advanced measurements – Partial Discharge, PI

Improved Data management needs to be implemented in

order to facilitate online monitoring

More intensive testing of short models

Testing against design values, not acceptance criteria

40Jan Petrik, 11/01/2019

Links to overview tables

41

Short model table - link, sharepoint

Short model description tables – link, DFS

Long coil tables – link, EDMS


https://espace.cern.ch/HiLumi/WP11/_layouts/15/WopiFrame.aspx?sourcedoc=/HiLumi/WP11/Shared Documents/tested_magnet_parameters.xlsx&action=default


Short Model Thermal Cycling Test Bench

42Courtesy of TE-CRG-CI, 11/01/2019

Jan Petrik, 25/10/2018 43

Recent Progress and Tests of Radiation Resistant

Impregnation Materials for Nb3Sn Coils

R. Bossert, S. Krave, G. Ambrosio, N. Andreev, G. Chlachidze, A.

Nobrega, I. Novitski, M. Yu and A.V. Zlobin

• 125 μm S2 Glass sleeve

• DOI: 10.1063/1.4860615, 2018

CTD 101K Insulation Under Pressure

Investigation of Alternative Materials for Impregnation

of Nb3Sn Magnets

Deepak R. Chichili, Jay Hoffman, and Alexander V. Zlobin

• 50% overlap of ceramic tape

• insulation thickness 0.250mm per cable

• DOI: 10.1109/TASC.2003.812892, 2003

Extrapolated value

10 kV/1mm

10 min. RI Test

Jan Petrik, 11/01/2019 44

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RI[G

Ω]

RI vs. Test Voltage and Time500V, 10 min, cables on stands - guard

1000V, 10 min, cables on stands - guard

2000V, 10 min, cables on stands - guard

3000V, 10 min, cables on stands - guardGate Opened

11T prototype Hi-Pot test history

45

Ref. L. Grand Clement, 03/10/2018Hi-pot issue of QH-coil insulation appeared

during post cold test reconfiguration

Short Model extended Test ProgramCourtesy of F-O Pincot TE-MSC-MDT

46

I. Insulation coil #120 to QH Left

Test on 1 QH only : coil#120 QH left

Coil#120 collared with coil#121 and tested at cold in single aperture magnet SP107

Measurement performed with coil#120 in the magnet (Magnet not disassembly)

Megger standard test at 1 kV and 2.1 kV 60s

Megger using ramp test up to 2.1 kV and 5 kV @ 1 kV/min

Insulation limit Coil#120 to QH left after cold test : 2800 V

Above: Break-Down Voltage (BRD)

Below: good insulation values (GΩ)

This is a non-destructive test

U[test] time measured measured

[V] [s] [GΩ] [nA]

1000 60 29.30 34.80

2100 1kV/min 5.84 364.00

2100 60 34.60 61.70

5000 1kV/min Brd 2831V

1000 60 97.70 10.50

2100 60 36.30 59.00

coil120 ---> QH Left


Insulation resistance





I. Insulation coil #114 to QHs

Insulation coil to QHs: coil #114 and coil #115

Coils tested and used in apertures: SP105a, SP105b, DP102

Megger standard test at 1 kV and 2.1 kV 30s

Megger using ramp test up to 2.1 kV and 10 kV @ 1 kV/min

Insulation limit between 2 kV and 2.3 kV: Above: Break-Down Voltage (BRD)


This is a non-destructive test

U[test] time measured measured measured

[V] [s] [GΩ] [GΩ] [GΩ]

1000 30 10.5 X X

2100 30 9.77 X X

1000 30 9.63 X X

2100 30 Brd 2122V X X

21001kv/min X

3.38X

2100 1kv/min X Brd 1799V X

10 000 1kv/min X XBrd 2305V / 3.4GΩ (1st ramp)

Brd 2191V / 3.22GΩ (2nd ramp)

2100 60 X X 6.51GΩ / 329nA

1000 60 X X 12.15GΩ / 84nA

10 000 1kv/min X X Brd 1979V / 3.04GΩ


coil114 ---> QH 114 OL

coil114 ---> QH 114 OL

coil114 ---> QH 114 OR

coil114 ---> QH 114 OR

coil114 ---> QH 114 OL

coil114 ---> QH 114 OR

coil114 ---> QH 114 OR

coil114 ---> QH 114 OL

coil114 ---> QH 114 OL

coil114 ---> QH 114 OL

II. Insulation coil #115 to QHs

Extra test on coil #115

Coil tested: used in apertures SP105a, SP105b & DP102

Insulation limit between 2kV and 2.4kV: Above: BRD


Non-destructive test

Large difference of BRD voltage when using standard test procedure or a ramp test (higher limit when using a ramp)

U[test] time measured measured measured

[V] [s] [GΩ] [GΩ] [GΩ]

1000 30 25.3 X X

2100 30 12.8 X X

1000 30 15.3 X X

2100 30 13.8 X X

2100 1kv/min X 4.16 X

2100 1kv/min X 4.25 X

10 000 1kv/min X XBrd 2183V / 2.16GΩ 1.01µA

Brd 2023V 2.20GΩ 919nA

10 000 1kv/minX X

Brd 2277V / 2.74GΩ / 832nA

Brd 2342V / 1.82GΩ / 2.4µA

2100 60 X X 3.02GΩ / 709nA

1000 60 X X 14.58GΩ / 70.1nA

2100 60 X X Brd 1221V / 2.25GΩ / 543nA

1000 60 X X 16.83GΩ / 60.8nA

coil115 ---> QH 115 OR

coil115 ---> QH 115 OL

coil115 ---> QH 115 OL

coil115 ---> QH 115 OR

coil115 ---> QH 115 OR

coil115 ---> QH 115 OL

coil115 ---> QH 115 OR

coil115 ---> QH 115 OL

coil115 ---> QH 115 OR


coil115 ---> QH 115 OL

coil115 ---> QH 115 OL

coil115 ---> QH 115 OR

III. Insulation coil #110 to QHs

Coil #110 : coil with interlayer QHs

Coil not tested at cold in a magnet . Coil used with coil #101 for a collaring test

Equipped with a “Dummy trace” in copper

No limit test (2 times in 2015)

Excellent insulation between QH and coil.

At high voltage (6kV) default in air between trace pads.

U[test] time measured measured

[V] [s] [GΩ] [GΩ]

1000 30 35.20 278.00

2000 30 33.00 97.30

3000 30 35.00 55.20

4000 30 34.80 45.80

5000 30 34.80 42.00

6000 30 31.80 32.40

7000 30 27.90 29.40

8000 30 22.20 1,67

9000 30 brd 0.39

1000 30 30.20 14.40

2000 30 28.70 13.50

3000 30 23.20 12.80

4000 30 18.20 10.80

5000 30 13.40 8.87

6000 30 9.51 brd

7000 30 brd brd

coil110 ---> QHs outer layer







coil110 ---> QHs inter layer










IV.Detection of insulation weakness on coils #114

/ #115 & #201 Coil #114 :

LMF protocol used (Megger in burn mode and CDG 7000 capacitor bench discharge)

Default appears at 2.5 kV and 3 kV

In the middle of a strip

Delamination identified on stainless steel surface in the same area (any correlation?)

U[test] time measured

[V] [s] [GΩ]

25 30 6.65

2000 30 12.1

2500 30 13.7

3000 30 0.26MΩ /370V

25 30 5.3MΩ

25 30 0.01MΩ

25 30 7

2000 30 12.3

2500 30 0.17MΩ /221V

25 30 16.3MΩ

25 30 17.6MΩYT114OR --> coil114


YT114OL --> coil114

burn test\ YT114OL --> coil114



YT114OR --> coil114

burn test\ YT114OR --> coil114

YT114OL --> coil114

YT114OR --> coil114


YT114OL --> coil114

Discharge 2 times at 500V with CDG7000 with a 0.5Ω resistance in serie

Default appears at 122.6 mm from the CS End Saddle



IV.Detection of insulation weakness on coils

#114 / #115 & #201 Coil #115 :


Default appears at 2.5kV

Inthe middle of a strip

No surface default


[V] [s] [GΩ]

25 30 8.4

2000 30 16.6

2500 30 0.36MΩ

25 30 14.4

2500 30 X

25 30 1.26MΩ

25 30 0.11MΩ

25 30 7.4

2000 30 15.7

2500 30 0.2MΩ

25 30 5MΩ

2500 30 X

25 30 1.12MΩ

25 30 0.01MΩ



Discharge 2 times at 500V with CDG7000 with a 0.5Ω resistance in serie :

Impossible because of a high value of Resistance for the CDG7000



YT115OL --> coil115


YT115OL --> coil115


YT115OL --> coil115



Discharge 2 times at 500V with CDG7000 with a 0.5Ω resistance in serie :

Impossible because of a high value of Resistance for the CDG7000

YT115OR --> coil115

YT115OL --> coil115

YT115OR --> coil115


YT115OR --> coil115

YT115OR --> coil115



IV.Detection of insulation weakness in coils

#114 / #115 & #201 Coil #201 :


Default appears at 4kV and 5.5kV

Default in air (not permanent)

Default at the surface of the trace between QH and Vtap

Dry spot


[V] [s] [GΩ]

25 30 6.9

2000 30 11.9

2500 30 12.9

3000 30 11.8

3500 30 11.4

4000 30 Brd surface

25 30 8.3

25 30 6.8

2000 30 11.4

2500 30 12

3000 30 10.3

3500 30 10.5

4000 30 10.4

4500 30 9.21

5000 30 5.79

5500 30 Brd surface

25 30 8.2






YT201OL --> coil201




YT201OL --> coil201



YT201OR --> coil201

YT201OR --> coil201





V. 11T short model coils insulation sum-up New document to sum-up 11T short model coils insulation EDMS 1838707:

Coil to loading plate

Coil to QHs

Coil to ground

QH to ground

EDMS 1838707

result result result

Equipment Step test values GΩ Step test values GΩ Step test values GΩ Remarks

HCMBHSP0003_101 NP glued trace

HCMBHSP0003_102 NP

HCMBHSP0003_103 NP

HCMBHSP0003_104 NP

HCMBHSP0003_105 PAIWI 1kV/30s 13.4 glued trace

BC 1kV/30s 16.5 BC 1kV/30s 14.2 Mirror test coil 101 + 105

AC 1kV/30s 12.2 AC 1kV/30s 180

FINAL 1kV/30s 15 FINAL 1kV/30s 35.8

PAIWI 1kV/30s 0.024 glued trace

ACT 7kV/30s 13.3 ACT 8kV/30s 1.55 no limit test

ACT 7.5kV/30s short ACT 8.5kV/30s short no limit test

BC 1kV/30s 0.074 glued trace

AC 1kV/30s 0.095

ACT 1kV/30s 29

ACT 5.8kV/30s 7.25 no limit test

ACT 6.5kV/30s short no limit test

FINAL 1kV/30s 3.24 FINAL 1kV/30s 29.5 FINAL 1kV/30s 22.5 SP101 (coil 106+ 107)

ACT 1kV/30s 3.5 ACT 1kV/30s 0.044 ACT 1kV/30s 0.028

ACT #106 1kV/30s 0.071

ACT #107 1kV/30s 34.4

PAIWI 1kV/30s 40 glued trace

ACT 7kV/30s 1.76 ACT 8kV/30s 1.55 no limit test

ACT 7.5kV/30s 0.64 ACT 8.5kV/30s 0.6 no limit test

BC 1kV/30s 9.4 BC 1kV/30s 5.2 SP102 (coil 106+ 108)

AC 1kV/30s 4.62 AC 1kV/30s 35

FINAL 1kV/30s 4.3 FINAL 1kV/30s 32 FINAL 1kV/30s 36.6


HCMBHSP0003_109 PAIWI 1kV/30s 40 glued trace

PAIWI 1kV/30s 30.2 model with interlayer QHs

PAIWI 6kV/30s 9.51

PAIWI 7kV/30s BRD

AC 1kV/30s 14.4 AC 1kV/30s 14.4

AC 5kV/30s 8.87 AC 2kV/30s 8.87 no limit test

AC 6kV/30s BRD no limit test

HCMBHSP0003_111 NP glued trace

BC 1kV/30s 9 BC 1kV/30s 36.7 BC 1kV/30s 29.7 SP103 (coil 109+ 111)

AC 1kV/30s 3.88 AC 1kV/30s 30.1 AC 1kV/30s 33.3

FINAL 1kV/30s 4.5 FINAL 1kV/30s 82 FINAL 1kV/30s 68.3

DP101 FINAL 1kV/30s 2.03 FINAL 1kV/30s 0.069 FINAL 1kV/30s 0.06 DP101 (SP102 + SP103)

SP103

HCMBHSP0003_108

SP102

HCMBHSP0003_110

SP(110+101)

11T short model insulation sum-up

SM101

HCMBHSP0003_106

HCMBHSP0003_107

SP101

Test condition

QH to Coil Coil to ground

Test condition

(coil + QH) to ground

Test condition


AC 1kV/30s 7.6

ACT 1kV/30s 6.6


AC 1kV/30s 11.4

ACT 1kV/30s 8.8

BC 1kV/30s 7.4 BC 1kV/30s 19 SP104a (coil 112+ 113)

AC 1kV/30s 4.52 AC 1kV/30s 28.5

FINAL 1kV/30s 5.25 FINAL 1kV/30s 24.3 FINAL 1kV/30s 62.8

BC 1kV/30s 6.86 BC 1kV/30s 55.1 BC 1kV/30s 44.8 SP104b (coil 109+ 112)


AC#109 1kV/30s 8.46

AC#112 1kV/30s 15.6

PAIWI 1kV/30s 5.5

ACT 1kV/30s 9.6

ACT 2.1kV/30s BRD 1.9kV

PAIWI 1kV/30s 13

ACT 1kV/30s 15.3

ACT 2.1kV/30s 12.8

ACT 10kV/30s BRD 2.2kV no limit test

BC 1kV/30s 1.54 BC 1kV/30s 11.3 SP105a (coil 114+ 115)

AC 1kV/30s 2.94 AC 1kV/30s 16.9



ACT#114 1kV/30s 11.8

ACT#115 1kV/30s 11

AC 1kV/30s 3.91 AC 1kV/30s 84 AC 1kV/30s 37.7 SP105b (coil 114+ 115)

AC#114 1kV/30s 8.2

AC#115 1kV/30s 11.2


FINAL 1kV/30s 2.01 FINAL 1kV/30s 0.58 FINAL 1kV/30s 0.623 DP102 (SP104b + SP105b)


HCMBHSP0003_116 NP

HCMBHSP0003_117 NP

BC 1kV/30s 2.2 BC 1kV/30s 28.9 BC 1kV/30s 20.7 SP106 (coil 116+ 117)



HCMBHSP0003_118 NP

HCMBHSP0003_119 PAIWI 1kV/30s 7.9



BC 1kV/30s 2.6 BC 1kV/30s 75 BC 1kV/30s 34.5 SP107 (coil 120+ 121)





HCMBHSP0003_201 PAIWI 1kV/30s 5.29 model with interlayer QHs

SP105b

SP106

SP107

DP102

HCMBHSP0003_113

SP104a

SP104b

HCMBHSP0003_114

HCMBHSP0003_115

SP105a

HCMBHSP0003_112

Electrical Tests and Root Cause Analysis of Insulation ...

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