Construction of a generator for power frequency magnetic field immunity test

Abstract

The power frequency magnetic field immunity test is a common test applied to a large variety of devices that must be checked for electromagnetic compatibility. Implementing this test is not difficult since it involves working with frequencies at which the generated magnetic field can be considered quasi-stationary. Considering the high price level of devices intended for use in electromagnetic compatibility laboratories, it may be worth contemplating assembling the equipment for this test on one's own. This paper includes a discussion on the requirements given by the relevant standards and their implications for the design of the test signal generator. Additionally, a complete design process for such equipment is provided, along with a discussion on the possibility of further improvements. The design of the test coil is adapted to allow its excitation from a powerful low-frequency amplifier, which opens up possibilities for the use of more advanced drivers. However, the test coil can also be powered using a normal mains transformer, simplifying the design of the entire device