Magnetic measurements on MBHSP102

L. Fiscarelli, O. Dunkel, S. Russenschuck,S. Izquierdo Bermudez, G. Willering, J. Feuvrier

21st July 2015

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Outline• MM systems (ambient and cryogenic temperature)• Performed measurement cycles• Results

• Straight section• TF• Allowed multipoles• Other multipoles• Comparison with ROXIE model• Comparison with MBHSP101• Ramp-rate dependency

• Integral field• Cold/Warm correlation

• Conclusions

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Measurement system 300 K Motor + encoder + slip-ring unit (MRU)

Fast Digital Integrator (FDI)

FuG low voltage power supply (40 V, 20 A)

DCCT Hitec MACC-plus

Search coil shafts (radius 22 mm, length 1.2 m)

Flexible software Framework for Magnetic

Measurements (FFMM)

A measurement is the average over 1.2 m

Number of turns (-) 256Inner width (mm) 13.41Inner length (mm) 1195.6Groove thickness (mm) 1.4Magnetic surface (m2) 3.37Center radius (mm) 21.33

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Measurement system 1.9 K Flexible software Framework for

Magnetic Measurements (FFMM)

Fast Digital Integrators (FDI)

Motor + encoder + slip-ring unit (MRU)

Vertical rotating shaft in liquid He

A measurement is the average over 250 mm

Number of turns - 36 36

Inner width mm 10.3 10.3

Inner length mm 431.5 246.5

Groove thickness mm 0.57 0.57

Magnetic surface m2 0.17 0.10

Center radius mm 21.5 21.3

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Performed measurement cycles

• At 1.9 K• Stair-step cycle• 3x machine simulation cycles• Ramp-rate study at 20, 50, and 100 A s-1

• Long flat-top (10 h) before a machine cycle

• No measurements at 4.3 K

Standardprogram

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Transfer function

0 2 4 6 8 10 120.94

0.95

0.96

0.97

0.98

0.99

1

1.01

1.02

kA

T k

A-1

TF

string

Meas p1Meas p2Meas p3Meas p4Meas p52D Model

o Measurements and ROXIE model in agreement for geometric TF

o Saturation overestimated by the model (+55 units)

o Measurement results on MBHSP101 and MBHSP102 are consistent

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Transfer function

Possible sources of error:

Iron propertiesUsing data from LHC production the discrepancy decrease by 20 units (from ~70 to ~50 units)

Packing factor of the yoke laminationsIts effect is up to ~15 units

Geometric Rather big displacements needed to explain 50 units(350 µm smaller coil gives ~15 units)

Courtesy of S. Izquierdo Bermudez

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102

104

106

0

0.5

1

1.5

2

2.5

3

H [A/m]

B [T

]

bhiron2LHC productionnomMa*1.511T Modif BH

• The main source of error is the magnetic properties of the iron:• Discrepancy ~ 80 units using ROXIE bhdata2• Discrepancy ~ 55 units using LHC production data• Discrepancy ~ 15 units using a modified bh data based on [1]

Modification on the BH data based on Wlodarski empirical relation.Nom. Correspond to the parameters reported in S. Russenschuck book

0 2000 4000 6000 8000 10000 120000.94

0.95

0.96

0.97

0.98

0.99

1

I [A]

TF

[T/k

A]

bhiron2LHC production11T Modif BHMBHSP102

[1] Z. Wlodarki. Analytical description of magnetization curves

Critical region!

Transfer function

Courtesy of S. Izquierdo Bermudez

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Allowed multipoles

Reference radius 17 mm

0 2 4 6 8 10 12

-10

0

10

20

30

40

50

60

b3

kA

unit

s

long pltstd cycle

20 A s-1

50 A s-1

100 A s-1

loadline

0 2 4 6 8 10 12-10

-5

0

5

10b5

kA

unit

s

0 2 4 6 8 10 12-1

-0.5

0

0.5

1

1.5

2

2.5b7

kA

unit

s

b3 changes by ~22 units during ramp

Offset on allowed multipoles after long plateau at nominal

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Allowed multipoles

Reference radius 17 mm

11.4 11.5 11.6 11.7 11.8 11.9

10.5

11

11.5

12

12.5

b3

kA

unit

s

long pltstd cycle

0 1 2 3

x 104

10.6

10.7

10.8

10.9

11

11.1

11.2

11.3

b3

s

unit

s

long pltstd cycle

Slow decay of b3 during long plateau at nominal

~0.5 units

Decay at injection~1.2 units

0.75 0.755 0.76 0.765 0.77 0.7750.5

1

1.5

2

2.5

3

3.5

4b3

kA

unit

s

long pltstd cycle

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Comparison with ROXIE (2D)

Reference radius 17 mm

0 2 4 6 8 10 12-15

-10

-5

0

5

10

15

20

kA

un

its

b3

Meas p1Meas p2Meas p3Meas p4Meas p52D Model

0 2 4 6 8 10 12-5

0

5

kA1u

nit

s

b5

Meas p1Meas p2Meas p3Meas p4Meas p52D Model

0 2 4 6 8 10 12

-1

-0.5

0

0.5

kA

un

its

b7

Meas p1Meas p2Meas p3Meas p4Meas p52D Model

0 2 4 6 8 10 120

0.5

1

1.5

2

kA

un

its

b9

Meas p1Meas p2Meas p3Meas p4Meas p52D Model

Offset of +5 units on b3

Offset on other allowed multipoles

Discrepancy on persistent currents

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Comparison with MBHSP101

Reference radius 17 mm

Offset added on data from MBHSP102 Larger persistent currents on MBHSP102

0 2 4 6 8 10 12-20

0

20

40

60

80

b3

kA

unit

s

MBHSP102MBHSP101

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Ramp-rate dependence

Reference radius 17 mm

    20 A s-1 50 A s-1 100 A s-1   20 A s-1 50 A s-1 100 A s-1

 n   Δ Bn   Δ An

2   -0.01 -0.07 -0.06   -0.13 -0.31 -0.42

mT

3   0.08 0.16 0.27   -0.02 0.02 0.06

4   0.01 0.02 0.04   -0.08 -0.14 -0.19

5   -0.07 -0.04 0.01   -0.03 -0.01 -0.01

6   0.00 0.01 0.03   0.01 -0.01 -0.03

7   0.01 0.01 0.02   0.00 0.00 0.00

8   0.00 0.01 0.04   0.00 -0.01 0.00

9   0.01 0.00 -0.01   0.00 0.01 0.01

Small effects: the cored cable is well performing

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Other multipoles

Reference radius 17 mm

 300 K at 20 A   1.9 K at 5 kA on three segments    

1.2 m    seg3 seg4 seg5   σn bn an   bn an bn an bn an   bn an2 0.33 6.76   1.75 2.73 1.22 3.56 0.69 3.67   0.53 0.513 9.50 -0.84   11.32 -1.78 11.82 -1.38 10.75 0.25   0.54 1.084 0.24 1.28   0.54 0.19 0.32 -0.33 -0.29 -0.20   0.43 0.275 1.56 -0.02   1.17 -0.59 1.39 0.20 1.65 0.58   0.24 0.606 0.00 0.03   -0.01 0.13 0.19 -0.42 0.09 -0.24   0.10 0.287 0.16 -0.02   0.16 -0.22 0.10 -0.07 0.12 -0.06   0.03 0.098 0.08 0.03   0.03 -0.04 0.05 -0.09 0.03 0.05   0.01 0.079 0.83 0.00   0.63 -0.13 0.64 0.02 0.62 0.22   0.01 0.1810 0.00 0.00   0.00 0.00 0.00 0.00 0.00 0.00   0.00 0.0011 0.40 0.02   0.22 -0.04 0.19 0.05 0.17 0.16   0.03 0.1012 -0.06 0.01   -0.03 0.06 -0.06 0.04 -0.07 0.02   0.02 0.0213 -0.10 0.00   -0.11 -0.01 -0.11 0.00 -0.11 0.00   0.00 0.0114 0.00 0.00   0.00 0.00 0.00 0.00 0.00 0.01   0.00 0.0015 -0.02 0.00   -0.02 0.00 -0.02 0.00 -0.02 -0.01   0.00 0.01

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Integral field

Reference radius 17 mm

  300 K   1.9 K  

n bn an   bn an

units at 17 mm

2 0.41 3.23   0.51 2.333 14.20 -1.81   14.54 -1.024 0.39 0.75   0.03 0.695 3.13 0.50   1.69 0.336 -0.06 -0.03   0.06 -0.077 0.07 0.06   0.22 0.068 0.07 0.00   0.02 0.009 0.70 0.00   0.63 0.0510 -0.01 -0.01   0.00 0.0011 0.35 0.05   0.22 0.0712 -0.06 0.00   -0.02 0.0113 -0.09 0.00   -0.11 0.0014 0.00 0.01   0.00 0.0015 -0.02 0.00   -0.02 0.00

Multipoles in agreement with respect to measurements at 300 K.

Thermal contraction of measurement shaft to be checked

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Cold/Warm correlation

Reference radius 17 mm

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15

cold

war

m

integral field

bn

an

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15

cold

war

m

central field

bn

an

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Conclusions• MBHSP102 has been tested at

• room temperature• cryogenic temperature

• Comparison with model• TF in agreement for geometric• Model overestimates saturation• Offset on allowed multipoles

• Cold/Warm in general agreement