A new nonresonant mode zero-voltage switching DC-DC converter using phase-shifted PWM

In order to reduce the size and weight of switch mode power supplies, resonant converters have attracted a lot of attention because of their low switching losses and low EMI. However, resonant converters include several disadvantages such as high resonant-current of voltages for semiconductor devices, high VA ratings for resonant components, variable switching frequency and complex control. To alleviate these problems, the authors proposed a new nonresonant mode DC-DC converter topology, which can achieve zero-voltage switching in a large load range with constant frequency. This can be realized using only a few additional small magnetic components with conventional bridge type PWM converters. The steady-state characteristics of the converter are illustrated in detail. All the analytical results are presented in the form of normalized graphics which can be widely applicable for design. A design procedure is illustrated and verified experimentally on a 500 kHz, 500 W breadboard