Temperature control of magnets in NMR systems

摘要

An NMR system comprises a permanent magnet 1 operable to produce a primary magnetic field, said permanent magnet having a nominal bulk temperature; first and second temperature sensors 10, 11 in thermal communication with the magnet and operable to monitor the local temperature of the magnet at respective first and second positions; at least one heater 5a-5d in thermal communication with the magnet; and a temperature controller 20 operable to control said at least one heater in response to the monitored local temperatures so as to maintain the nominal bulk temperature of the magnet at a predetermined value. A method of controlling the temperature of a permanent magnet in an NMR system is also provided.