Passive power factor correction power supply circuit

Abstract

The invention provides a passive power factor correction power supply circuit which comprises an AC (Alternating Current) power supply, a correction inductor L, a correction capacitor C2, a correction capacitor C1, a filtration capacitor C3, a resister RL and a full bridge rectification circuit D1, wherein the AC power supply is serially connected with the correction inductor L and the correction capacitor C2 to form a loop; two ends of the correction inductor L are parrallelly connected with the correction capacitor C1; two ends of the correction capacitor C2 are parallelly connected with the input end of the full-bridge rectification circuit D1; the output end of the full-bridge rectification circuit D1 are respectively and parrallelly connected with the filtration capacitor C3 and the resister RL; and the two ends of the resister RL are output ends. The passive power factor correction power supply circuit provided by the invention has the following beneficial effects: by virtue of performing proper lectotype and optimization on the correction inductor L, the correction capacitor C1 and the correction capacitor C2, a passive power factor correction function for the input of the AC power supply is realized, and under the conditions of rated AC input and rated DC (Direct Current) load, the power factor can be up to 0.96; and the passive power factor correction power supply circuit has the advantages of simple circuit, convenience in use, high reliability of a correction circuit, and the like.

Description

Technical field [0001] The invention belongs to the field of power supply circuits, and in particular relates to a passive power factor correction power supply circuit. Background technique [0002] Most railway signal switching power supply modules require power factor correction (PFC). In the existing technology, these power supplies usually use active power factor correction. Because the active power factor correction DC bus voltage is relatively high, the filter capacitor working on the DC bus has high withstand voltage and performance requirements; at the same time, the voltage stress of the power device is also relatively large in the subsequent DC / DC conversion circuit, especially When the power factor correction is out of control, high voltage will be formed on the DC bus, which directly causes the filter capacitor on the DC bus and the power devices in the DC / DC conversion circuit to be broken down. From the analysis of the failure causes of this type of power supply in...

AI Technical Summary

Problems solved by technology

Because the active power factor correction DC bus voltage is high, the filter capacitor working on the DC bus has high withstand voltage and performance requirements; at the same time, in the DC / DC conversion circuit of the subsequent stage, the voltage stress of the power device is also large, especially When the power factor correction is out of control, a high voltage will be formed on the DC bus, which will directly cause the filter capacitor on the DC bus and the power device in the DC / DC conversion circuit to be broken down and fail.

From the analysis of the failure causes of this type of power supply in recent years, the failure rate of the active power factor correction (PFC) part is relatively high, resulting in a decrease in the reliability of this power supply. There is a railway DC switching power supply due to the active power factor correction circuit faults, technical problems that lead to its low reliability

Images