Multi-channel output direct current-direct-current converter

Abstract

The invention discloses a multi-channel output direct current-direct-current converter which comprises a common inverter bridge leg and a plurality of independent inverter bridge legs; each independent inverter bridge leg comprises a first power transistor with an inverse-parallel diode and a second power transistor with an inverse-parallel diode; the common inverter bridge leg comprises an upper unit and a lower unit which are formed by connecting a power diode and a third power transistor in series; and output circuits are respectively connected at the middle points of each independent inverter bridge leg and the common inverter bridge leg. The device works at the constant frequency, and each path of output voltage is regulated by using the phase shifting between the independent inverter bridge leg of the path and the common inverter bridge leg, and all the path of the output voltage are fully independent and not mutually affected; each independent inverter bridge leg is taken as the leading bridge arm in the phase shifting control, and all the power transistors in the bridge arms can be turned on with zero voltage; the common inverter bridge leg is taken as the lagging bridge leg in the phase shifting control, and the power transistors in the common inverter bridge leg can respectively realize zero-current switching through the two power diodes and under the action of reset capacitors in all the paths of the output circuits.

Description

technical field [0001] The invention relates to a DC-DC converter, in particular to a high-power full-bridge soft switch isolation type multi-channel output DC-DC converter. Background technique [0002] The multi-output DC-DC converter has a very wide range of applications. The basic requirements for the multi-output DC-DC converter are high efficiency, low cost, small size, simple control method, input and output isolation, and output voltage of each channel. Can be adjusted etc. At present, there are many technologies that can meet one or more of the above requirements at the same time. However, most of these technologies use one or two power switch tubes to form a forward or flyback circuit, which cannot be applied to high-power output occasions. . For example, in the Chinese patent titled "A Multi-output DC / DC Converter and Its Conversion Method", the announcement number is 1389971, and the announcement date was January 8, 2003. For conversion, the output terminals o...

AI Technical Summary

Problems solved by technology

However, this circuit has many disadvantages: an additional circuit is required to control the auxiliary power switch; the other outputs can only be fully adjusted when the first output is fully loaded; and all secondary windings are in the same transformer, so there is no Easy to expand the number of output channels

The disadvantages of this technology are: the first output and the second output are actually converted by the half-bridge converter, and the output capacity is not as good as that of the full-bridge converter; each output is in an asymmetric working state, and the transformer is not fully utilized; The outputs interact with each other, and the coupling is serious; the control strategy involves the coordination between the duty cycle and the phase shift, which is difficult to realize; and the control strategy becomes more complicated as the number of output channels increases, which is not conducive to the expansion of the number of output channels

Images