A CALIBRATION METHOD FOR BEAM DCCT OF J-PARC MAIN RING

Yuki Omori #,A), Yoshinori HashimotoB), Takeshi ToyamaB) , Satoru OtsuA) A) Mitsubishi Electric System & Service Co., Ltd, 2-8-8 Umezono, Tsukuba, Ibaraki, 305-0045, Japan

B) High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba Ibaraki, 305-0801

Abstract The DC-Beam Current Transformer (DCCT) of J-PARC Main Ring (MR) can measure beam current between about

0.2 mA and 20 A with three full-scale ranges of 200 mA, 2 A, and 20 A. Its frequency response is up to 20 kHz.

Conversion of measured current into circulating proton number in MR is done with dividing by rf frequency, and

measurable maximum number is 5 x 1014 protons. A calibration has carried out with precise digital multi meters, and

then it was confirmed accuracy for current measurement is order of 0.1 % in case of DC current at environmental

temperature of between 23 and 26 degree C. In this paper, mainly actual calibration methods and results were described.

J-PARC MR DCCT

1.

J-PARC (MR) DCCT [1]

KEK-B

parametric

DCCT [2, 3]

FINEMET

20A

DC 20kHz

MR

DCCT

1%

DCCT

MR

[4]MR

[5, 6]DCCT

DC

1e-4 Digital

Multi-Meter (DMM)

2. DCCT

1. DCCT[1].

DCCT 1 DC1kHz parametric modulation ( sine wave

)

2

AC L/R

DC 5Hz 5Hz 20kHz

SUM

DC AC

Negative Feedback

2. DMM .

1 2

2 DCCT

DC AC 50 turn

DCCT 20A 400mA

DMM 1 2 DCCT

TP4

TP5 ISO

DCCT 10V

20A 2A

Feedback

TP5 10

___________________________________________

# z-omori@post.j-parc.jp

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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1[7,8]

Product Current Accuracy Noise

HP 6626A 0 2 A 0.04%+550µA 0.1mApp

Keithley 6220A 0 100mA 0.1%+50µA 10µApp

2 DMM ( Keithley )[8]

Model Item Digit Accuracy@reading

2002 Input Current 8 1/2 58 µA@100mA

2010 Isolate Output 7 1/2 27µV@1V

2000 Shunt /AMP Voltage 6 1/2 77µV@1V

DC

3 DMM

Timing ON / OFF

DMM ADC

10 PLC ( 200 ms ) 100

cycle

ON OFF DC

3.

4.

5.

3. DMM

DMM

2 ( 2: 2002, 2010)

3 2002, 2010, 2000

1)

DMM 4 2002

2) DMM 3

100cycle 3)

DMM2002

4 5

100

DMM 2002

100

2

3 DMM

1e-4

DMM

DCCT

5e-4

DCCT

23.0 26.0

6. DCCT 2A, 20A

4. DC DCCT

DC DCCT 2

3

100 20A 0

5A 50 turn

6220A 6220A (100 mA)

5 20A Function Generator (Biomation 2416A)

(100 400 mA)

4.1 Linearity

2A 20A

DCCT ISO 6

INPUT DMM2002

50turn

100

0.999

0.9995

1

1.0005

1.001

0.001 0.01 0.1 1 10

NEW2000/2010OLD2000/2010

DMM 2000/2010

INPUT [V]

for DCCT Calibration

0.9985

0.999

0.9995

1

1.0005

1.001

1.0015

0.001 0.01 0.1 1

2010/2002

DMM2010/2002

INPUT [A]

0

2

4

6

8

10

12

0 0.5 1 1.5 2

0 5 10 15 20

20A Range Input [A]

2A Range

20A Range

y = 0.0026223 + 5.0584x R= 1 y = -0.00728 + 0.50192x R= 1

ISO Output [V]

2A Range Input [A]

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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10[V]/full-scale current[A]

3 2A

1%

3 2, 20A DC

[V]/[A]

[V]/[A]

error

2A 5.0 5.0584 +1.17

%

20A 0.5 0.5019 +0.38

%

7. (a) 2A , (b)2A Fitting

7. (a), (b)

2A, 20A 9

2A (a)

0.1A 0.5%

9

20A (b)

2A

1A -1.5%

9

2. DMM

1e-4

2A

±0.05% 20A ±0.3%

1

(2A 0.2A 20A 2A )

2A ±0.01% 20A

±0.1%

8. DCCT TP4, TP5, ISO

(a) 2A (b)

20A

TP4, TP5 ISO

8. (a) (b) 2A 20A

2A

TP4, TP5

DCCT

ISO

7

DCCT

20A (b)

TP4

DCCT

TP5 TP4

TP5 TP4

TP4-TP5

-0.015

-0.01

-0.005

0

0.005

0 5 10 15 20

Linear Fitting9 order Fitting

Residual Rate

INPUT (measured current x 50 turns) [A]

b)

-0.002

-0.001

0

0.001

0.002

0.003

0.004

0.005

0.006

0 0.5 1 1.5 2

Linear Fitting9 order Fitting

Residual Rate

INPUT (measured current x 50 turns) [A]

a)

-0.001

0

0.001

0.002

0.003

0.004

0.005

0.006

0 0.5 1 1.5 2

TP4TP5ISO

Residual Rate from Linear Function

INPUT (measured current x 50 turns) [A]

a)

-0.03

-0.02

-0.01

0

0.01

0.02

0 5 10 15 20

TP4TP5ISO

Residual Rate from Linear Function

INPUT (measured current x 50 turns) [A]

b)

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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ISO

TP5

7 ISO

TP4

DCCT

DCCT

5.

DCCT

rf

9

MR 30 GeV rf 1.71

MHz CW DCCT

9(a)

(b)

9. (a)

(b)

(b)

1e-4

6.

2 3 DMM

DMM

DCCT

DC 5e-4

DCCT 2A

±0.01% 20A ±0.1%

9

10V

DMM 5e-4

(1)DCCT

20kHz AC

DMM AC 0.1% (2)

DCCT

145kW 45

(3)

(4)

(5)

DCCT

(6) 0.01%

DMM

(7)

ADC (Yokogawa WE7272 ) DCCT

[1] Y. Hashimoto, et al., . [2] M. Arinaga, et al., Nucl. Instr. And Meth. 499(2003)100-

137. [3] S. Hiramatsu, KEK Internal 2004-4. [4] R. Muto, [5] Y. Sato, et al., [6] T. Toyama, et al., [7] Agilent, http://www.home.agilent.com/ [8] Keithley, http://www.keithley.jp/

0

2

4

6

8

10

12

14

0 2 4 6 8 10 12

y = 1.033e-05 + 1.2945x R= 1

NML OUTPUT [V]

DCCT ISO-OUTPUT [V]

a)

-0.0001

-5 10-5

0

5 10-5

0.0001

0 2 4 6 8 10 12

Residual Rate

DCCT ISO-OUTPUT [V]

b)

Proceedings of the 8th Annual Meeting of Particle Accelerator Society of Japan (August 1-3, 2011, Tsukuba, Japan)

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