Error field predictability and consequences for ITER

We conduct a linear study of n=1 error fields due to tilted and shifted misplacements of central solenoid and poloidal field coils within tolerance. Error fields in magnetic confinement fusion can cause large, sometimes sudden, losses in confinement, which has severe consequences for fusion performance. Their origin and optimal correction therefore remains a topic of pertinent interest for study in planning future magnetic confinement devices. We thus begin with an analysis of the necessity of error field correction for daily operation in ITER using updated scaling laws for the error field penetration threshold. We then investigate the optimal correction of each error field using the error field correction coils as well as the RMP ELM coils. We also consider the predictability of error field overlap across early planned ITER scenarios and, as measuring error fields in high power scenarios poses risks to the device, the potential for extrapolation to the ITER Baseline Scenario (IBS). We find that some error field sources extrapolate well to IBS, while others do not and could benefit from careful metrology.