Conveners
Thu-Af-Or24 - Diagnostics and Test Results of Coils
- Emanuela Barzi (Fermilab)
- Michael Parizh (GE Global Research)
Among various superconducting magnet diagnostics, acoustic techniques are valuable for characterizing mechanical instabilities associated with lengthy training, premature quenching and other performance limitations. While acoustic emissions from magnets were studied since early 80s, techniques involving external acoustic excitation have so far been of limited use. As such techniques are...
Superconducting magnets include various electrically-insulated metallic parts. The stray capacitance between these elements can be monitored and utilized to acquire information about the magnet condition and behaviour.
It is well known that dedicated capacitive sensors can be used to monitor the local strain. Furthermore, it was recently proposed to use a stray-capacitance monitoring system...
It is relevant to establish a reliable coil winding techniques which is free from local defects and/or delamination of REBCO tape strand. A coil is usually tested by measuring transport current-voltage characteristics as a whole, however, the position and distribution of the defects can not be identified from such global measurements. This prevent us from clarifying the mechanism of the...
This paper presents a method to mitigate screening current by manipulating temperature in a high temperature superconductor (HTS) pancake coil. Named as “Thermal Eraser”, it utilizes an electric heater that is optimally designed to “create” a target temperature profile in the HTS pancake coil. The key idea is to control field and temperature dependent critical current Ic (B,T) of “individual”...
Conduction-cooled magnets are gaining popularity as Helium reserves diminish. High-temperature superconductors, such as YBCO, can theoretically deliver ultra-high, > 20 T, magnetic field while cooled by an inexpensive and efficient single-stage GM cryocooler. At 20 K common materials still maintain high thermal conductivity, which ensures fast cooldown and fast recovery of a magnet after...
The U.S. Magnet Development Program is developing Canted-Cosine-Theta (CCT) magnet technology for future high field accelerator magnets. The CCT concept prevents Lorentz force accumulation by placing turns within precision-machined grooves that are separated by ribs and a spar that intercept forces, substantially reducing the stress in the conductor. CCT technology has been advanced through...
In the previous systematic research on short models of round CORC-like cables the range of design parameters like the core diameter, lay angle, pulling force etc. have been identified that should be respected in long-length cable production. Based on this knowledge we have manufactured 40 m long cable with two layers each comprising four Furukawa-SuperPower tapes 4 mm wide. Tapes are laid in...
