Review on the flyback converter design for multi-output

With the increasing demand for DC loads, DC-DC converters have become indispensable in modern power electronic architectures. With high-voltage applications typical DC-DC converter topologies are required which include isolation for safety and voltage level conversion. Among various isolated converter topologies, the flyback converter is widely favored for low-power applications, typically under 100 W, due to its simplicity and cost-effectiveness. Like other DC-DC topologies, the flyback converter can operate in either continuous conduction mode or discontinuous conduction mode (DCM). The work have focused on the design and performance analysis of a flyback converter operating in DCM, with a specific emphasis on magnetic component design and loss evaluation. A 55 W multi-winding flyback converter employing a passive snubber circuit is studied and implemented. The loss analysis is done with switch losses around 3.4W and the coupled inductor core losses around 1.5W and copper losses around 0.8W. Furthermore, a comparative analysis of passive voltage clamping techniques is presented to address voltage spikes across the primary switch. The most common passive snubbing techniques in the primary side switch node which includes the Resistor Capacitor Diode Clamping and Transient Voltage Suppressor Diode clamping is discussed. Using LTspice, an open-loop simulation is developed to validate operation. The necessity of primary snubbing and the implementation of valley switching are described and validated through simulation results. A hardware prototype is developed to validate the same for the input voltage varying from 90V to 400V, and with three output voltage of 12V, 16V and 18V.