Multilevel high-voltage flyback type switch power supply

Abstract

The invention discloses a multilevel high-voltage flyback type switch power supply comprising a rectification module, a current sampling resistor module, a control chip, a driving isolation module, a transformer, n stages of series-connected capacitors and n stages of MOS tubes, wherein n is a natural number which is greater than or equal to 2. The transformer is provided with multiple stages of primary coils, and the multiple stages of capacitors are connected in series, i.e. various types of voltage n-diving, such as voltage averaging, voltage tri-sectioning, voltage quartering, etc., are performed on the inputted high voltage so that n+1 stages of level input can be realized, voltage withstood by each stage of the primary coil is reduced, voltage withstood by each stage of the MOS tube is reduced, and thus current withstood by each stage of MOS tube is reduced. The structure of the switch power supply is improved, and a mode of input power is converted into the mode of series connection of multistage voltage and low current so that a problem that high voltage withstanding cannot be realized and heating is severe due to direct series connection of the MOS tubes is solved, the problem that the MOS tubes cannot withstand high current is also solved simultaneously, and thus application range of the switch power supply is widened.

Description

[0001] technical field [0002] The invention relates to the technical field of switching power supplies, in particular to a multi-level high-voltage flyback switching power supply. [0003] Background technique [0004] The existing flyback switching power supply mainly has the following two types: [0005] One is the single-tube single-ended flyback switching power supply that supplies power to a single coil on the primary side; this switching power supply has the following problems during use: 1) The maximum withstand voltage of the MOS tube MOSFET is only 1500V, so the input of this switching power supply The working voltage can only be less than 800V to work in the safe working area, and it cannot be used in the case of higher input voltage; 2) single coil power supply, the average current on the MOS tube is large, and the MOS tube heats up seriously. [0006] The second is the dual-tube single-ended flyback switching power supply that supplies power to a single coil...

AI Technical Summary

Problems solved by technology

[0009] Aiming at the deficiencies in the above technologies, the present invention provides a multi-level high-voltage flyback switching power supply with safe use, good reliability and wide application range. The switching power supply realizes multi-level primary coil power supply, and converts input power to It is a multi-level voltage, which not only increases the input voltage, but also solves the problem that high voltage cannot be input

Images