BOOST PFC circuit based on nonlinear average current control

Abstract

The invention provides a BOOST power factor correction (PFC) circuit based on nonlinear average current control. The BOOST PFC circuit comprises a totem pole BOOST PFC main circuit and a control branch circuit; the totem pole BOOST PFC main circuit comprises an input side, a capacitor C0, a resistor Rs, a first diode D1, a second diode D2, a third diode D3, a first field effect tube Q1, a second field effect tube Q2, an inductor L1 and an output side; the control branch circuit comprises a digital controller, an operational amplifier, an integrating capacitor C, a switch S, a comparator and atrigger; a control rate equation of the control branch circuit is that: FORMULA (14); the left side of the control rate equation (14) is realized by using a resettable integrator; and the right side of the control rate equation (14) is realized by using the digital controller. By the BOOST PFC circuit based on nonlinear average current control, electromagnetic interference of bridge-free BOOST PFC is reduced, and the shortcomings of unstable light load during the single-circle control and complicated design of the integrator during the nonlinear average current control are overcome.

Description

technical field [0001] The invention relates to a power factor correction circuit, in particular to a BOOST PFC circuit. Background technique [0002] A large number of frequent use of power electronic devices has caused serious harmonic pollution to the power grid, so a power factor correction (PFC) circuit must be introduced to make its input current harmonics meet the existing harmonic requirements. Power factor correction has been developing towards high efficiency, simple structure, easy control, and reduced EMI. Therefore, bridgeless BOOST PFC circuit has attracted more and more attention as an effective way to improve efficiency. The bridgeless BOOST PFC circuit omits the rectifier bridge of the traditional BOOST PFC circuit, reduces the on-state loss of the diode, and greatly improves the efficiency. However, the EMI of the traditional bridgeless BOOST PFC is relatively large. As an evolution of the totem pole BOOST PFC, the EMI is much smaller, but the traditional ...

AI Technical Summary

Problems solved by technology

[0003] In order to reduce the electromagnetic interference of the bridgeless BOOST PFC and overcome the shortcomings of the existing single-cycle control with light load instability and nonlinear carrier control with complex integrator design, the present invention provides a light-load stable and simplified integrator design Totem Pole BOOST PFC Circuit Based on Nonlinear Average Current Control

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