KAGRA Logbook

PEM (Center)

tatsuki.washimi - 17:22 Thursday 08 August 2024 (30780)

Investigation of a Large Coil position for Magnetic Injection @ CS

[Obayashi, Washimi]

We investigated some positions in the CS to make a Large Coil for Magnetic Injection.
As coil shapes, we are considering the following options:

4m x 4m square (Virgo-like: https://logbook.virgo-gw.eu/virgo/?r=49094)
4m x 4m bent square (LIGO-like: https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=52395)
6m x 2m rectangle

(-X, +Y) area
- We found the unused cable rack at a height of 2.0 m from the ground (Fig.1). It looks possible to locate a 6m x 2m rectangle coile here, without any additional equipment (Fig.2)
- There is enough space to locate a 4m x 4m square coile here, but it is necessary to create new additional equipment (Fig.3)
(-X, -Y) area
- The height of the upper cable rack is 4.0 m from the ground. It looks possible to locate a 4m x 4m bent square coil, but it might affect the working space. (Fig.4, Fig.5)
(+X, +Y) area
- The height of the upper cable rack is 4.5 m from the ground and the width of the PEM shelves is about 4.0 m. (Fig. 6)
Other areas
- We measured other 6m spaces. (Fig.7, Fig.8)

Images attached to this report

Comments to this report:

kaori.obayashi - 0:55 Thursday 15 August 2024 (30829)

[Washimi, Obayashi]

We simulated the magnetic injection in the CS for the three different coil shapes, with each coil positioned in the (-X, +Y) area.
This simulation was under the assumption of 92 rolls, and 1A current (RMS), and the value of the magnetic field is observed at a height of 1 m from the ground (z=1m).
The validity of this simulation is still being verified, so these are only preliminary results.

4m x 4m square (Virgo-like):
- This coil can produce the strongest magnetic field at BS, ITMX, and ITMY.
4m x 4m bent square (LIGO-like):
- The difference in the value of the magnetic field between ITMX and ITMY is the smallest.
6m x 2m rectangle:
- This coil does not lose much performance compared to a square, at most a little less than 2 times difference.

Images attached to this comment

tatsuki.washimi - 16:59 Friday 16 August 2024 (30854)

To follow the discussion in today's meeting (JGW-T2415938) I calculated the power and heat on the large coil (2m x 6m, N=92), for the 2 amplifier types.

Fig.1: Maximum supplied current
Fig.2: Power and Heat (larger amplifier)
Fig.3: Power and Heat (smaller amplifier)
Fig.4: Comparison of heat generation

Images attached to this comment

tatsuki.washimi - 17:55 Monday 30 September 2024 (31156)

I measured some geometries for the LargeCoil location at BS-IYC.

I marked the coil-edges and the cable rack holders. (Fig. 1, Fig.2)
- The holders' interval was about 1.5m.
- The length of the holder was 34cm. (Fig.3)
- The bottom side of the cable rack was 201cm from the floor (Fig.4). The width of the cable rack was 20cm.
- There is a trench just below the cable rack (Fig.5).
I investigated the aluminum frame near the BS-cooler, holding a cable rack and some cooling water pipes/filters, as a good reference. (Fig.6)
- I couldn't find any documents on the klog or the JGWdoc.
- It stands with 2 vertical bars.
- 3cm Al frame (Fig.7, maybe Misumi KNEFS6-3030)
- The corner parts between the frames were 28mm (Fig.8). maybe Misumi HBLFS6
- The corner parts between the frames and the floor were about 90mm. I couldn't find it in Misumi.
- The parts holding the cable rack were "<N>NEGUROSU 7ARS 1" (Fig.9)