Quantified PFC based on full voltage peak detection

Abstract

The invention relates to a quantitative PFC based on full voltage peak detection. The input reference voltage generates a peak clock signal through the peak time detection module, which is transmitted to the calculation half sine wave time module, calculates the peak interval time, and then is transmitted to the decision step time module, step time encoding module, half A sine wave time division module divides half of the sine wave time according to the preset accuracy, and the step time is obtained by determining the step time module and transmitted to the step time encoding module. And the corresponding time point generates a step time code and transmits it to the reconstructed sine wave voltage code table module, and the sine wave voltage of the required voltage value is output by the reconstructed sine wave voltage code table module and filtered by the low-pass filter module, and the output is smooth The sine wave reference voltage is used as a reference voltage by the subsequent circuit. The quantized PFC of the present invention only depends on the time information of the peak point, so it has resistance to the deformation of the sine wave input to the circuit, can track the change of the sine wave period, and does not depend on the peak value information.

Description

technical field [0001] The invention relates to a quantitative PFC based on full voltage peak detection. Background technique [0002] With power factor correction PFC voltage down conversion switching LED driver such as figure 1 It consists of a diode (D1), an inductor (L), a transistor (Q0), a sense resistor (R CS ) and the controller. The controller consists of a signal feedback comparator (Comp1), a clock (Clock), a trigger-reset flip-flop logic gate (RS flip-flop), and a drive circuit. When power is applied to the input and ground, current will flow from the input (VIN) through the LED array, L, Q0, and R CS flow to ground. Such as figure 1 As shown, this is called the first cycle (Phase1). In this called the first period (Phase1), when the current flows through the resistor R CS when R CS The voltage will step up and will be applied to one end of the comparator. The input signal at the other end of the comparator is the comparison reference voltage (VSINE), ...

AI Technical Summary

Problems solved by technology

It can be seen from Equation 2 that because the input voltage VIN is greater than zero and deformed, I Rcs The waveform cannot be reproduced as a sine wave and becomes abnormal I Rcs envelope, causing the PFC value to drop, its waveform is as figure 2 shown

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