For the purpose of enhance the accuracy and sensitivity of FRA of transformer winding deformation fault diagnose, this paper made several improvements on the traditional FRA. Regarding the signal source's insufficiency, we changed the impulse replaces the sine frequency sweep signal. The test results showed: after the improvement, the test cycle reduces and the signal frequency response range is broader. We also used the FFT and EMD method to improvement the analysis of frequency response curves, this increased the analysis accuracy and diagnose sensitivity, find the fault characteristic. This study can be used on the development of transformer winding fault diagnosis, detection and test methods.