24VDC 36W flyback converter with EMC improvement for railway application

Nowadays, switching DC-DC power supplies are widely used in industry. The flyback converter is at the forefront of the railway industry due to its wide input voltage range at low powers, input and output isolation, reliability and simplicity of design. Due to the low efficiency of the flyback converter, soft switching and active clamping techniques are used to increase the efficiency, which results in high cost. In this thesis, it is aimed to design a flyback converter with high efficiency according to literature, low cost according to industry, EMC filtered, DIMMABLE, compliant with EN 50155 and EN 55015 Railway standards to meet the need for led lighting in railway systems by using hard switching technique and passive RC snubber. The designed flyback converter complies with EN 50155 and TS EN 50121 Railway standards. Flyback converter with DIM feature has 77VDC-137.5VDC input voltage range, 24 VDC output voltage, 20VDC output voltage in DIM mode, 1.5A output current, 36W power and approximately 90% efficiency.