Abstract:

BACKGROUND: Currently, the medical device is toward smaller, portable development. Portable medical equipments are mainly powered by lithium batteries. Battery life is weak, unable to work in the wild.
OBJECTIVE: In order to improve power reliability and endurance of portable medical devices, to design a high efficiency, credible and low cost sine-wave inverter.
METHODS: High frequency inverter technology is selected. It contains high frequency transformer, which can fulfill voltage ratio regulation and electricity isolation, push-pull converter and single-phase bridge circuit as the main circuit, degrade noise, raise efficiency, reduce voltage ripple. Power switching tube adopts a RCVD cushion circuit to ensure safety working. Sine pulse width modulation as control form is selected by using integrated circuit SG3524 and ICL8038.
RESULTS AND CONCLUSION: The experimental model machine reduces the volume to 1/4 of the traditional inverter, system efficiency reaches 86%. The experimental result indicates the distortion factor of the output voltage waveform is less than 5% and output is 220 V/50 Hz commercial power in complicated operating mode. The Inverter can be used as a power supply battery that is simple, credible, easy to debug.