Power conversion device powered by pulsating direct current

Abstract

The invention discloses a power supply switching device supplied by a pulsating direct current. The pulsating direct current is provided with a first end and a second end; the first end of a first switch and the first end of the pulsating direct current are connected; the first end of a second switch and the first end of the pulsating direct current are connected; the first end of an energy storage capacitance and the second end of the second switch are connected; the second end of the energy storage capacitance and the second end of the pulsating direct current are connected; the first end of a third switch and the first end of the energy storage capacitance are connected; the second end of the third switch and the second end of the first switch are connected; a control unit is provided with a plurality of signal output ends which are respectively connected with the control ends of the first switch, the second switch and the third switch and respectively control the on-off of the switches; an output unit is provided with at least two input ends; the first end of the output unit and the second end of the third switch are connected, and the second end of the output unit and the second end of the pulsating direct current are connected. The pulsating direct current can be converted into all kinds of power supplies without using a smooth filter capacitance, so that the occupied area is reduced, the performance is improved, the reliability is improved, and the integration is easy.

Description

Technical field [0001] The invention belongs to the field of power converters, and particularly relates to a power conversion device powered by pulsating direct current. Background technique [0002] Most electronic appliances and electrical equipment use alternating current as their power source, but in fact, the internal devices of many electrical appliances and equipment cannot directly use alternating current to work. In most cases, the alternating current needs to be converted into pulsating direct current through a rectifier circuit, and then the power conversion device Convert pulsating direct current into various power sources they need. [0003] Because the voltage fluctuation range of the pulsating direct current is too large, it is often difficult for the power conversion device to work normally. Therefore, the range of the voltage fluctuation must be reduced to an acceptable range. The solution in the prior art is to place a large-capacity capacitor at both ends of th...

AI Technical Summary

Problems solved by technology

[0004] However, the existence of the above-mentioned large-capacity smoothing filter capacitor also brings many problems, such as increased volume, increased cost, excessive surge current at the moment of starting up, large current harmonic distortion on the power supply grid, low power factor, and electromagnetic interference. Big and so on

At high temperature, the electrolytic capacitor will also burst due to performance degradation, which will deteriorate the performance of the whole machine, reduce reliability, shorten life span, and bring safety hazards

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