Soft switching isolation DC-DC converter for train auxiliary power supply

Abstract

The invention provides a soft switching isolation DC-DC converter for train auxiliary power supply. The converter comprises a boost module used for carrying out boost processing on a power supply voltage accessed to the converter to obtain a predetermined high voltage, a resonance module used for realizing the zero-current turn-off based on a circuit state at a current moment, and an inversion module used for inverting the predetermined voltage into a predetermined low voltage according to a turn-off state of the current boost module, and the boost module, the resonance module and the inversion module are sequentially connected in series. According to the technical scheme, the total size and weight of a circuit can be reduced, meanwhile, higher accuracy can be guaranteed for the operationwithin the whole range of the output power, and the control manner of the converter does not need to be changed even under the no-load condition.

Description

[0001] 1. Technical field [0002] The invention relates to power electronic technology, in particular to a soft-switching isolated DC-DC converter for train auxiliary power supply. [0003] 2. Background technology [0004] In order to increase comfort and meet higher speed requirements, modern railways are in great need of a continuous energy supply for auxiliary equipment such as air conditioning, lighting, pressure protection, etc. Due to the different voltage levels of European locomotives, the locomotive power is transferred to the carriages through a supply line (rated voltage varies from 1kVac to 3kVdc). For example, Belgian railways are powered by 3kV DC voltage. The customer supply voltage connected to such a power supply unit has a range from 24V DC for battery chargers to three-phase 400V AC for three-phase customers. The frequency of the output voltage can be fixed at 50Hz or variable frequency. [0005] At present, in the power supply system of auxiliary equipm...

AI Technical Summary

Problems solved by technology

[0008] The invention provides a soft-switching isolated DC-DC converter for train auxiliary power supply, which adopts a new half-bridge zero-current pulse width modulation (HB-ZCS-PWM) technology, and realizes electrical isolation through a lightweight intermediate frequency transformer , so as to solve the problem of large and heavy low-frequency transformers for electrical isolation in traditional auxiliary power supply systems

At the same time, the technical problems to be solved by the present invention are mainly: the existing zero-current dc-dc converter has a large number of passive components, large values ​​of inductance and capacitance, relatively large size and weight of the entire circuit, and light load and Overloaded control methods are different, etc.

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