Utility companies are facing challenges with the growing presence of renewable energy sources. Harmonics and impedance from other renewable energy sources can introduce unfamiliar harmonic instability to a multi-power supplied system. With the grid’s electrical characteristics constantly changing, there is a need for harmonic filters that can be regulated dynamically by varying real-time conditions to maintain effective harmonic mitigation. The traditional filtering approach involves installing low-pass filters which necessitates additional components, driving up manufacturing costs. Power Transformers, however, can provide a filtering effect. It is an interesting phenomenon that not many people are aware of. Therefore, the aim of this study was to investigate whether parasitic elements in a power transformer can be utilized for designing a harmonic filter. Specially, this study undertakes a detailed analysis of the high-frequency characteristics of a double-split dry-type transformer, pivotal for bridging various voltage levels within the grid, highlighting its significance in harmonic filtering. By employing Matlab-Simulink fast Fourier transform (FFT) analysis, the AC/DC source harmonics source was closely examined to identify any harmonic components present in the waveform. The circuit impedance characteristics across the harmonic frequency spectrum can be thoroughly examined using a recognized model. According to the simulation results, inherent filtering properties in the transformer operate less effectively at low-voltage side. Therefore, more low-pass filter elements are needed to attenuate the harmonic level.