Dec 20, 2010 Replacement Solenoid

Items for followup from previous meeting

1. None

Tentative Agenda

1. Background (Elton)
2. Discussion of items Ettore sent via e-mail

Date: Tue, 14 Dec 2010 17:12:03 -0500
From: Ettore Salpietro <ettore@jlab.org>
To: Elton Smith <elton@jlab.org>, George Biallas <biallas@jlab.org>,
   Tim Whitlatch <whitey@jlab.org>
Subject: Re: Resources for new solenoid (fwd)

Dear All
We will carry out a scoping study to compare a solenoid made of 
Rutherford and CIC conductors.
Very likely the solenoid with CICC  will require current of~ 15 kA and 
forced flow super-critical He cooling.
In addition HTS current leads could used. It is therefore necessary to 
asses the impact of this choices on the other plants( power supply, 
cryogenics, buildings).
In particular I would be interested to have your reaction to the 
following operating conditions of the solenoid:
Conductor current~15 kA
Forced flow cooling inlet temperature 4.5K,total mass flow rate < 10 
   gr/sec, inlet pressure < 10 bars, pressure drop~2 bars.
Provide He gas at 20 or ~70K for the HTS bus cooling .
Power supply, bus bar routing and switches for fast discharge shall also 
be considered.
Thanks
Ettore

Minutes

Attending: Ettore, Elton, George, Tim, Jonathan, Elliott

1. Discussion of implication of cable-in-conduit conductor (CICC) choice on infrastructure in four main areas
   1. Power supply. Current ~ 15KA, voltage 5-10 V. (Could existing power supply 3KA/10V be converted to 6KA/5V?)
      • Elton can obtain cost estimates for this power supply
   2. Cryogenic plant
      • Primary circuit: Forced flow He at 4.5K, < 10g/s, ~5-10 bar, pressure drop < 2 bar.
      • Secondary circuit: Deliver intermediate temperature He gas at 20-70 K to HTS vapor cooled current leads
      • Jonathan will investigate feasibility/cost of modifying existing refrigerator or purchasing new to deliver these requirements
   3. High-current HTS (17KA) vapor cooled leads
      • Ettore will provide this information based on Sultan design
   4. Fast protection system (external), with response time of ~0.5 s.
      • Commercial 4 parallel breakers 5KA each (20KA total), 2KV max. Two independent systems for redundancy
      • Ettore will obtain details of these existing systems.
2. Jonathan will provide details of the cryo plant to Ettore
3. George mentioned that the G0 CICC conductor may have been operated at reduced pressure and lower current, which may be more compatible with standard JLab operation.