GMPS Transductor UpgradesAnd Realtime B Field Measurement for

Reference Magnet

Kent Triplett, Xiaolong Zhang

Main Objectives

• Back up present system.• Improve the GMPS stability and accuracy.• Improve the B-dot stability and accuracy.• Methods:

Commercial Current Transformer UpgradeHall Probe Realtime B field measurement system

Transducer Original Designing

• The transducer in the in booster reference magnet measures the excitation current to the gradient magnets and thus regulate the GMPS system for the B:Imax and B:Imin.

• The original designing was a current transformer of 1200A with a output of 1245A/10V.

• It’s essential to Booster operation.

Evolution of Current Transducer

• The transducer system was upgraded a few times to present of water cooled 7500A transductor and relatively new electronics of 7500A/43V.

• The resolution and accuracy of the system is unknown.

• There might be 720Hz noise signal present. (“In order to reduce the transmission line mode excitation, the power supply have been designed as 12-phase supplies with a basic ripple frequency of 720Hz” TM-405)

Proposed Upgrades

• Since it’s critical for Booster operation, and it looks like we don’t have the spare, the backup or upgrade of the system is needed.

• There are a few commercial current transformer readily available with modern electronics from Hitec, LEM/Danfysik and ZES .

• Their specification (0 - 50KHz): Accuracy: < 3 ppm Output noise: < 6 ppm

• Advantage of the upgrade: Improve the accuracy of the GMPS current monitoring. Better for the feedback/feedforward system.

Specifications - ITP Current Transducers

Electrical

Model Symbol ITP 2000-SPR ITP 2000-S/SP1

ITP 2000-SBPR Units

Former Danfysik Model STH-2000I STH-2000IHF STH-2000U

Polarity Bipolar

Secondary Nominal Current Isn ±1 ±2 - A

Nominal voltage output Max. output load current Max. output load cap.

Von

Io,max

Co,max- -

±1053

VmAnF

Ext. burden resistor max Ext. burden resistor min

Rb,max

Rb,min

1.50 - Ω

Ω

Transfer ratio (Ip/Is)N 2000 1000 - -

Transfer ratio (Ip/Vs)G - 200 A/V

Max nondestructive overload Min overload trip value

Ip,max

Ip,min5x

1.3x5x

1.3xIpn

Ipn

Offset - Initial - Drift vs. Temp. - Drift vs. Time

- <2<0.1<1

<2<0.6<1

ppmppm/°C

ppm/month

Transfer ratio - Deviation - Deviation vs. Temp. - Deviation vs. Time

- <4

<0.1<1

<50<2<2

ppmppm/°C

ppm/month

Linearity Deviation Linearity Deviation vs. Temp.

Xd

Xd,temp<2

<0.1<4-

ppmppm/°C

Output noise rms -<0.01<3.5<5.5

<0.01<3

<5.5

<0.15<5.5 <16

ppm,rmsppm,rmsppm,rms

Dynamic resp. slew rate Dynamic resp. delay time

dl/dttd

>20<1

TBDTBD

>20<1

A/µSµS

Bandwidth ±3dB f 0-50 0-300 0-50 kHz

Realtime B Field Monitoring

• By measuring the B field during the cycle, we’ll be able to measure the optics more accurately.

• It’ll give us another instrument for B-dot system backup.

• Give more data for booster modeling and beam dynamics studying.

• The available commercial product of Lakeshore 460 3-axial Gaussmeter will be a good option.

Specifications of Lakeshore 460

Product Price Total

Gaussmeter, 460, $5,975.00 $5,975.00

Two-axis probe: 8 in long $1,537.00 $1,537.00

Probe, metal transverse, 0.06 x 0.18 x 8 in

$598.00 $598.00

111

Backup Slides

Benefits of These Upgrades

• We could measure the real time main B field and gradient.

• Build a better GMPS feedback/feedforward system (might be 4 additional 20A current feedforward system).

• Improve the B-dot timing system to better synchronize the beam transfer and other beam diagnosing.

Pros:$5575/unit.Used in the labat beam line.

Cons:4-6 weeks delievery

PSU1000HF: $2615 each. This requires +/- 15 V power supply. If connecting to one of our power analyzers, we have cables made to provide this supply.SAT2000: $7699.00 each. Includes transducer head, power supply and cabling up to 30m. Both are in stock in up to 10 pcs.

Lakeshore 455 Single Channel

Power Line Frequency Variation

At fermilab, D. Herrup using 60Hz±30 mHz forEstimation the need for cogging

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