The built-in acoustic-magnetic multimodal single sensor shows great potentials in highly sensitive perception of partial discharge (PD) ultrasonic signals and simultaneously integrating the differential sensing advantages of ultrasonic and ultra-high-frequency sensors for different PD defects. However

the compatibility between its substrate

SF6

and fault decomposition gases is critical for its integration into gas-insulated switchgear (GIS). Based on this

the paper constructed an experimental platform for the compatibility of SF6 and its fault decomposition gases with the substrate of the GIS PD built-in acoustic-magnetic multimodal single sensor. The platform was used to conduct thermal accelerated experiments on the compatibility of the acoustic-magnetic multimodal sensor substrate with SF6 and its fault decomposition gases under different experimental temperatures. Using Fourier transform infrared spectroscopy (FTIR)

gas chromatography-mass spectrometry (GC-MS)

scanning electron microscope (SEM)

X-ray photoelectron spectroscopy (XPS)

and piezoelectric coefficient (d33) detector

we analyze SF6 gas composition changes and surface morphology

elemental variations

and piezoelectric property degradation of the sensor substrate. The experimental findings indicate that polyvinylidene fluoride (PVDF)

piezoelectric ceramic transducer (PZT)

and poly (vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) do not have impacts on the composition of SF6 gas. However

PZT and PVDF can react with SOF2

a decomposition product of SF6

resulting in a reduction of its concentration. Moreover

the sensor substrates of PZT and PVDF are susceptible to corrosion by the fault decomposition gases. Both PZT and PVDF substrates suffer corrosion from fault gases

the F element on the substrate surface of PZT and PVDF sensors increases

and the piezoelectric properties of PZT deteriorate. These findings provide essential references for the design and application of built-in acoustic-magnetic multimodal sensors in GIS.