Design optimization of an ironless inductive position sensor for the LHC collimators

The Ironless Inductive Position Sensor (I2PS) is anair-cored displacement sensor which has been conceived to be totallyimmune to external DC/slowly-varying magnetic fields. It can thus beused as a valid alternative to Linear Variable DifferentialTransformers (LVDTs), which can show a position error in magneticenvironments. In addition, since it retains the excellent propertiesof LVDTs, the I2PS can be used in harsh environments, such asnuclear plants, plasma control and particle accelerators. This paperfocuses on the design optimization of the sensor, considering theCERN LHC Collimators as application. In particular, the optimizationcomes after a complete review of the electromagnetic and thermalmodeling of the sensor, as well as the proper choice of the readingtechnique. The design optimization stage is firmly based on thesepreliminary steps. Therefore, the paper summarises the sensor'scomplete development, from its modeling to its actualimplementation. A set of experimental measurements demonstrates thesensor's performances to be those expected in the design phase.