Direct current-direct current voltage conversion device and fuel cell power system

Abstract

The embodiment of the invention discloses a direct current-direct current voltage conversion device, a fuel cell power system and a new energy vehicle, relates to the technical field of electromechanics, and can effectively reduce ripple current. The direct current-direct current voltage conversion device comprises a voltage conversion part and a control part, wherein the voltage conversion part is used for converting a first voltage into a second voltage through alternate charging and discharging of at least two voltage conversion modules, wherein at any moment of voltage conversion, at leastone first conversion module in a charging state and at least one second conversion module in a discharging state exist in the voltage conversion modules, the first voltage and the second voltage aredirect-current voltages, and the second voltage is higher than the first voltage; and the control part is electrically connected with the voltage conversion part and is used for controlling the voltage conversion modules to be charged or discharged according to a preset time sequence so as to enable ripples of the second voltage to be less than a preset ripple threshold value. The device disclosedby the invention can be used in DC voltage conversion.

Description

technical field [0001] The invention relates to the field of electromechanical technology, in particular to a DC-DC voltage conversion device and a fuel cell power system. Background technique [0002] As a clean energy source, fuel cells are being used more and more widely, such as the power system of new energy vehicles. However, the dynamic response of many fuel cells (such as hydrogen fuel cells) is slow at present, and it is difficult to adapt to the rapid response requirements of vehicle acceleration. Moreover, the stack voltage of fuel cells is generally between 48 and 400V, which is difficult to meet the needs of the current 540V voltage platform for logistics vehicles. [0003] For this reason, a DC / DC (direct-direct current) voltage converter can be added at the output end of the hydrogen fuel cell to increase the output voltage and speed up the dynamic response. However, the DC-DC voltage converter in the center of the existing technology tends to generate large...

AI Technical Summary

Problems solved by technology

However, the DC-DC voltage converter in the center of the existing technology tends to generate large high-frequency current ripples, which will affect the service life and reliability of the motor controller connected to the output end of the DC / DC boost converter and the high-voltage auxiliary power battery. sex

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