High sensitivity in condition monitoring is a key link in digital electrical equipment operation and maintenance,besides,it is also an important premise of status analysis and life cycle management. The partial discharge (PD) transient earth voltage (TEV) detection is the primary mean to insulation state perception of high voltage switchgear. The detection sensitivity of TEV method is affected by the type and location of the defect,the location of TEV detection. However,there is no systematic research on this subject by now. A finite difference time domain (FDTD) electromagnetic wave simulation model based on the measured pulse current waveform is established. The stuexplores the effects of factors such as the rise-up time of PD pulse current waveform,the position of discharge source,and the direction of pulse current on the amplitude and attenuation degree of TEV. A series of PD tests and TEV measurements are conducted in a laboratory setting to identify the primary factors influencing TEV detection sensitivity. The results reveal that both the rise-up time and spatial position of PD significantly affect the amplitude of the TEV signal. Specifically,the amplitude of the TEV signal exhibits a decreasing trend as the pulse current's rise-up time increases. Notably,a tenfold increase in the rise-up time results in a decrease in TEV signal amplitude within the range of 3.17 to 3.37 times. Furthermore,the TEV signal's attenuation degree in the busbar room compartment is approximately 9.5 to 10.0 times greater than that observed in the cable compartment. This conclusion has reference value for testing the sensitivity of TEV detection.