Magnetic field distributions in high voltage test hall when impulse voltage generator discharges

To protect equipment and personnel in high voltage test hall effectively, it is necessary to know the distributions of space electromagnetic field and frequency spectrum characteristics. A set of transient magnetic field waveform measurements and digital reconstruction method was used in discharge and withstand test of impulse voltage generator. Distributions of magnetic field and waveform characteristics have been measured. The results show that magnetic field of discharge test is larger than that of withstand test either in lightning impulse voltage test or in switching impulse voltage test. The magnetic field of many points have exceeded the level of computer misoperation and the rise time of waveform is also very short, so necessary protection and an EMC test to the equipment working in high voltage test hall are very necessary