Constant voltage output switching power supply device with high power factor and control method thereof
A high power factor, switching power supply technology, applied in output power conversion devices, conversion of AC power input to DC power output, high-efficiency power electronic conversion, etc., can solve the problem of high cost, complex circuit structure, and poor system stability and reliability. etc., to achieve the effect of high power factor
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Publication Date
- 2017-01-18
- Estimated Expiration
- Not applicable · inactive patent
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Abstract
Description
technical field
[0001] The invention relates to the technical field of switching power supplies, in particular to a constant voltage output power supply device and a control circuit thereof.
[0002] technical background
[0003] There are certain requirements for the power factor of the switching power supply connected to the AC grid, because if the power factor is not enough, it will cause a certain degree of pollution to the grid. The IEC International Electrotechnical Commission has put forward clear harmonic requirements for lighting fixtures, namely the IEC61000-3-2 standard. Judging from the actual application situation, the requirements for power factor are mostly higher than the standard regulations.
[0004] The closest prior art of the present invention: publication number: CN102290997A, publication date: 2011-12-21, name: a constant voltage output control circuit and a switching power supply of a switching power supply controller, providing a constant voltage out...
Examples
Embodiment Construction
[0031] The present invention will be described in further detail below according to accompanying drawing and embodiment:
[0032] like figure 1 As shown, a high power factor constant voltage output switching power supply of the present invention includes a rectification filter circuit, a power converter, an output voltage feedback circuit, an inductor current zero-crossing feedback circuit, a chip power supply circuit and a control circuit.
[0033] The rectification and filtering circuit includes a rectification bridge and an input filter capacitor, which are used to rectify and filter the AC input voltage, and the voltage after rectification and filtering is a half-sine wave.
[0034] The power converter is used to transform the AC voltage into a DC constant voltage output voltage, and realize the power factor correction function at the same time.
[0035] The output voltage feedback circuit is used to sample the output voltage as the voltage feedback signal of the control ...