A compact 1.5 kW resonant switchmode rectifier

A small 1.5 kW off-line switch-mode rectifier has been developed for use in 48 V or 24 V rack power systems. The convection cooled rectifier is only 143 mm wide, 260 mm high, and 250 mm deep, and weighs only 6 kg. Two-thirds of the rectifier volume is heatsink. This has been achieved by using relatively high switching frequencies, 200 to 450 kHz for the main isolating converter and 70 kHz for the sinewave input current boost converter. Sinewave input current maximizes the use of standby generator capacity and minimizes main noise injection into the telecommunication network. The switch-mode components are housed on one printed circuit board, allowing easy access to all componentry for service. All user-required adjustments are accessible via holes through the rectifier front panel and can be adjusted without removing the rectifier from the rack