An open circuit permanent magnets saturated fault current limiter has the advantages of simple structure

low loss and low operating cost

and so that it has a good applied prospect. Permanent magnets may lose their magne-tization at high temperatures. Therefore

it is great practical significant to carry out calculation and analysis of PMF-CL temperature field. For a linear PMFCL

the B-t curve of the magnetic flux density of a core over a period of time isobtained by using finite element software to analyze the magnetic field

and then the loss is calculated according tothe B-P curve of the core

and the loss of the permanent magnet is taken into consideration to analyze the tempera-ture field at the conditions in which the normal working state and the extreme continuous fault state of the bus. The re-sults of simulation shows that the permanent magnets of the novel current limiter are all in the temperature range ofgood magnetic state at the normal working state and the extreme continuous fault state of the bus

and thus during thetransition of the bus fault in the middle of two steady states

PMFCL meets design temperature and magnetic proper-ties so that this PMFCL has good thermal stability of magnetic field.