Double-beam interference type temperature measuring device for transformer

The invention discloses a double-beam interference type temperature measuring device for a transformer. The double-beam interference type temperature measuring device comprises a 980nm pump light source, wherein the 980nm pump light source is connected with a 980/1550nm wavelength division multiplexer, an Er-doped fiber ring, an optical isolator, an offset fiber, a first optical fiber coupler, a second optical fiber coupler and a third optical fiber coupler through fiber in the optical signal propagation direction in order; and the third optical fiber coupler is connected with a spectrum analyzer and the 980/1550nm wavelength division multiplexer through fiber. The double-beam interference type temperature measuring device for a transformer has the advantages of being simple in the double coupled structure, being low in manufacturing cost, being high in system compatibility and being low in related loss of polarization; and when the difference between the splitting ratio and the interference arm length for tw