A New Resonant Converter Operating above Resonance for DC to DC Energy Conversion

There are two major penalties occur in off-line switching power supplies: high switching losses, and an operating environment, which is very responsive to the radiation of Electromagnetic Interference (EMI) and Radio Frequency Interference (RFI). The switching losses are a largest initiator of EMI (conducted) and RFI (radiated), so their control and reduction is a major profit to the power supply designer. Resonant techniques offer a hope for greatly reducing the switching losses and hence the factors causative to the EMI and RFI. In addition, this technique offers many other advantages such as small volume, and light weight of components due to high switching frequency, high efficiency and low reverse recovery losses in diodes owing to low di/dt at the switching instant. This work presents a resonant DC to DC converter which operating at a high frequency. The proposed circuit consists of an L-C-L resonant inverter and a bridge rectifier. Output stage of the converter is filtered by means of a low pass filter. A PID controller is provided in feedback loop for better performance. Finally, a simulation model is developed in MATLAB/SIMULINK environment. Moreover the projected topology is apparently suitable for power electronics production applications such as switching power supplies, battery chargers, telecom power supplies etc.