Conversion circuit for high-voltage input and low-voltage output

Abstract

The invention discloses a conversion circuit for high-voltage input and low-voltage output, belonging to the technical field of power electronic technology. The conversion circuit comprises a capacitance divider circuit, a switch circuit, a rectifying circuit and a filter circuit, wherein the output end of the capacitance divider circuit is connected with the input end of the filter circuit through the switch circuit and the rectifying circuit; two ends of the divider circuit and the switch circuit are connected with the anode and the cathode of the power supply, respectively; three step down transformers are connected serially at the preceding stage of the rectifying circuit, two ends of the rectifying circuit are connected with the output end of the switch circuit, and three full-wave rectifiers are connected in parallel at the back stage of the rectifying circuit; the filter circuit is a capacitor filter circuit, and two ends of the filter circuit are connected with two output ends of a rectifier, respectively. The conversion circuit inputs high voltage class, outputs stable direct-current voltage, has a simple circuit structure, small switching stress, simplified transformer design, high power supply utilization ratio, good power supply quality, high stability and security coefficient and low cost, and is suitable for high-voltage and high-speed application situations, such as subways, bullet trains, high-speed rails and the like.

Description

technical field [0001] The invention relates to a step-down conversion circuit in the technical field of power electronics, in particular to a high-voltage input-low-voltage output conversion circuit. Background technique [0002] The 24V low-voltage DC power supply applied to electronic equipment and control circuits is an important part of the low-voltage power distribution system of subway locomotives. With the rapid development of my country's subway, bullet train, and high-speed rail technology, the demand for low-voltage DC power supplies is becoming stronger and higher, and the requirements are getting higher and higher. The low-voltage power supply with small size, light weight, good stability, high safety factor, and ultra-high voltage input meets the development requirements of high-speed trains and has a good application prospect. [0003] The 1500V input-24V output subway locomotive power supply specifically includes two voltage conversion links, one is the high...

AI Technical Summary

Problems solved by technology

[0007] To sum up, the existing high-voltage input-low-voltage output power supply has a low input voltage level, and the structure and control are more complicated, while the power supply with higher input voltage has high cost, more complicated topology, and poor output voltage stability. Suitable for high-speed and over-voltage occasions such as subway locomotives

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