Fiber Optic Quench Detection Via Optimized Rayleigh Scattering in High-field YBCO Accelerator Magnets

YBCO coated conductors are one of the primary options for generating the high magnetic fields needed for future high energy physics devices. Due to slow quench propagation, quench detection remains one of the primary limitations to YBCO magnets. Fiber optic sensing, based upon Rayleigh scattering, has the potential for spatial resolution approaching the wavelength of light, or very fast temporal resolution at low spatial resolution, and a continuum of combinations in between. This work will optimize Rayleigh scattering such that it provides the appropriate combination of spatial and temporal resolution for quench detection in YBCO magnets.The research institution has recently developed an experimentally validated 3D quench propagation code that will accurately define the acceptable range of spatial and temporal resolutions for effective quench detection in YBCO magnets. This code will evaluate present-day and potentially improved YBCO conductors. The data volume and speed requirements for quench detection via Rayleigh scattering require the development of a high performance trigger/data acquisition system, including algorithm and platform performance benchmarking.The safe operating range of spatial and temporal resolutions were defined for present-day YBCO conductors. Initial development and benchmarking of a high performance trigger and data acquisition system that will be required for quench detection via Raleigh scattering were successfully achieved. Phase II will provide detailed understanding about quench detection system design via the aforementioned simulation tools. The software development and technology studies from Phase I will be used to build a high performance trigger system that will be used to demonstrate Rayleigh scattering based quench detection technology.The behaviors quantified during this work will have great benefit in high energy physics applications, high field nuclear magnetic resonance, as well as a spectrum of grid applications, including energy storage, generators for wind turbines, and fault current limiters. The quench sensors developed here are essential for the reliable, safe operation of YBCO based systems.