Single phase power factor correcting analog circuit without need of detecting DC output voltage

Abstract

The invention provides a single-phase power factor correction analog circuit without the requirement of detecting the DC output voltage. The single-phase power factor correction analog circuit detects the transient current of the shunt resistance of a power circuit by a current detection circuit, then converts the transient current into a current effective value by a first effective value conversion circuit; meanwhile, an input voltage effective value gaining the circuit and an output DC voltage generation circuit respectively gain the input voltage effective value and the output DC voltage; then a calculation circuit calculates an input current regulation signal according to the voltage and current values output by all circuits; subsequently, a control signal forming circuit generates a control signal according to the input current regulation signal and the unit voltage generated by a unit voltage generation circuit; subsequently, a comparison circuit outputs corresponding PWM pulse sequences by comparing the carrier wave signal generated by a carrier wave signal generation circuit with the control signal; furthermore, the turn-on and turn-off of a power tube is driven by a driving circuit; therefore, the correction of the power is realized, meanwhile, the circuit can be effectively simplified as the DC output voltage is not required to be detected.

Description

technical field [0001] The invention relates to a single-phase power factor correction analog circuit, in particular to a single-phase power factor correction analog circuit which does not need to detect DC output voltage. Background technique [0002] Up to now, single-phase active power factor correction (APFC) technology has been widely and deeply developed and applied, bringing considerable economic and social benefits. The wide application of APFC has also led to the emergence of a variety of new control algorithms. Different power level control algorithms are not the same, and different control algorithms have different advantages and characteristics. However, looking at all the existing control algorithms, it is necessary to detect the APFC DC output voltage in real time, and use the obtained voltage signal as a control signal source. In addition, the purpose of real-time detection of the DC output voltage is also to be used as a closed-loop control of the output vo...

AI Technical Summary

Problems solved by technology

In addition, the purpose of detecting the DC output voltage in real time is also to use it as a closed-loop control of the output voltage and to monitor whether the output voltage is under-voltage or over-voltage, which increases the hardware cost and the complexity of the control.

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