M.A. Romashchenko1, A.V. Gudkov2, O.Y. Makarov3

1-3 FSBEI of HE “Voronezh State Technical University” (Voronezh, Russia)

1 kipr@vorstu.ru; 2 andrej23.vrn@gmail.com; 3 kipr@vorstu.ru.

Formulation of the problem. Compliance with electromagnetic compatibility (EMC) standards is an important requirement for most pulsed AC/DC converters. However, during preliminary tests, a high level of conductive interference emission into the supply network is often detected. The elimination of this problem requires several iterations of additional work and subsequent product inspections in the EMC laboratory, which leads to a delay in the design time and an increase in the time of use of expensive measuring equipment. Modeling of conductive interference at the stages of circuit design makes it possible to solve the problem in a shorter time without the need for a large number of laboratory measurements.

Purpose. Development of a technique for modeling conductive interference in the LTspice circuit modeling program using the example of an AC/DC flyback converter. The technique will allow for an engineering assessment of the conductive interferences level, optimize the converter filters, which reduces the design time spent on achieving the required EMC standards.

Results. The proposed technique was used to build a model of a 120-watt flyback converter and simulate the conductive interference generated by it in the frequency range 9 kHz-30 MHz. The absolute error of the model data relative to the spectrograms of the converter ranged from +6.5 dBuV to -4.3 dBuV in the frequency range of 9 kHz-7 MHz. At higher frequencies, the error increased.

Practical significance. The developed technique makes it possible to perform a preliminary assessment of the level of conductive interference with subsequent optimization of the converter circuit, which reduces the subsequent quantity of product modifications. The same technique can be used by developers at remote work.

Romashchenko M.A., Gudkov A.V., Makarov O.Y. A technique for modeling conductive interferences of an AC/DC flyback converter. Radiotekhnika. 2024. V. 88. № 7. P. 16−20. DOI: https://doi.org/10.18127/j00338486-202407-03 (In Russian)

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