  High-field REBCO magnets contain several coils with many turns. {For these
magnets,} electro-thermal quench is an issue that magnet designers need to take
into account. Thus, there is a need for fast and accurate software to
numerically model the overall performance of full-scale magnets. High
temperature superconductors can be modeled using different techniques for
electro-magnetic (such as $H$-formulation and $A-V$ formulation) and thermal
(finite element method) analysis. However, it takes a lot of time to model the
electro-magnetic and electro-thermal behavior of superconductors simultaneously
in a commercial software, especially for non-insulated or metal-insulated
coils. We have developed a novel software programmed in C++, which performs
coupled electro-magnetic and electro-thermal analysis using variational methods
based on Minimum Electro-Magnetic Entropy Production (MEMEP) and Finite
Difference, respectively. The developed software is applied to axi-symmetric
fullscale magnets of more than 30 T field strength for transient design
(thermal quench reliability), taking screening currents into account. We show
that the magnets incorporating non-insulated coils {are more reiable against
quench} than the metal insulated coils. Also, {realistic} cooling conditions at
boundaries is essential for such simulations. The model developed can be used
for a quick and complete electro-magnetic and electro-thermal analysis of
superconducting high field magnets.
