The Safety of Aircraft Exposed to Electromagnetic Fields: HIRF Testing of Aircraft Using Direct Current Injection

Even the original developers of Bulk Current Injection now make the point that the use of BCI at aircraft level will become increasingly difficult. Direct Current Injection has the potential to replace aircraft level BCI, while also solving many of the longstanding problems of BCI. These problems include lack of synergism, inaccurate current distribution within bundles and limited numbers of injection sites due to time and cost considerations. However, calibration, the question of how much power to apply as a function of frequency, is much more complex to answer for DCI than BCI. One potential method of calibration, the use of modal skin currents, is developed in this work. This is the first time that DCI calibrated using skin-currents has been shown to generate cable currents which are at least as accurate as BCI. Power levels of approximately 20 kW are required for small aircraft. Numercial modelling based on Method of Moments, and skin and bundle current measurements are employed.