Performance analysis of electromagnetic compatibility of wireless electric field measuring instrument

To research the electromagnetic environment of ultra high-voltage direct-current(HVDC) transmission lines, we developed a wireless electric field measuring instrument. Moreover, we selected 30 prototypes to test the electromagnetic compatibility (EMC) performance of electric measuring instrument, and analyzed the test results of electric measuring instrument's EMC performance in detail. Combining electromagnetic working environment with interference routes of the electric measuring instrument, some important factors which were susceptible to electromagnetic interference (EMI) in testing and the corresponding improvement measures were proposed. Test results show that the most obvious faults occur in the radiated, radio-frequency, electromagnetic field immunity test and surge immunity test. But the faults of electromagnetic radiation and surge harassment can be conquered by increasing the thickness of the sheet copper inside the equipment and adding transient suppression diodes and filter at the device power supply port.