A switch cabinet fault diagnosis method based on an on-line indirect temperature measurement mode

The invention discloses a switch cabinet fault diagnosis method based on an on-line indirect temperature measurement mode. Judgment of fault states of the switch cabinet is conducted through temperature real-time monitoring carried out on an indirect temperature measurement point and an environmental temperature measurement point used for installation of temperature measurement sensors on the outside of the switch cabinet. According to the method, physical modeling and measurement point selection are firstly carried out; a temperature theta[2](t) of the indirect temperature measurement point and the temperature theta[0](t) of the environmental temperature measurement point are measured in real time; then a temperature theta[1](t) of a lumped heat source center inside the switch cabinet and a load ideal temperature theta[1](t)[LX] of the lumped heat source center and /or a determined load ideal temperature theta[2](t)[LX] of the indirect temperature measurement point are calculated; the measured temperature an