High-power factor constant-current circuit and power source

Abstract

The invention is suitable for the field of power factor correction, and provides a high-power factor constant-current circuit and a power source. The high-power factor constant-current circuit comprises an electromagnetic compatible module, an input rectifying and filtering circuit, a power converting and power factor correcting circuit, an output rectifying and filtering circuit and a sampling and amplifying circuit. The electromagnetic compatible module is used for receiving the input of alternating current, inhibiting the conducted interference in the circuit and outputting the alternating current; the input rectifying and filtering circuit is used for rectifying the alternating current to be a pulse direct current; the power converting and power factor correcting circuit is used for carrying out power conversion and power factor correction on the pulse direct current according to a sampling feedback signal; the output rectifying and filtering circuit is used for rectifying and filtering the current output by the power converting and power factor correcting circuit to improve output waveform; and the sampling and amplifying circuit is used for sampling the voltage and the current output by the output rectifying and filtering circuit to output the sampling feedback signal. The invention realizes the output of the high-power factor constant current and reduces a primary power factor correcting circuit with simpleness, reliability and low cost.

Description

technical field [0001] The invention belongs to the field of power factor correction, in particular to a high power factor constant current circuit and a power supply. Background technique [0002] In recent years, with the development of electronic technology, some communication equipment such as computers have become more and more popular and widely used in various fields. Among them, the harmonic pollution of the power grid and the low power factor of the input terminal have become increasingly prominent. Internally, these devices require a power section that converts AC to DC. In this conversion process, due to the existence of some nonlinear components, although the input AC voltage is sinusoidal, the input AC current is seriously distorted and contains a large number of harmonics, which not only reduces the power factor of the input circuit, but also affects the common The power system generates pollution, causing circuit failures. Obviously, using effective correcti...

AI Technical Summary

Problems solved by technology

In this conversion process, due to the existence of some nonlinear components, although the input AC voltage is sinusoidal, the input AC current is seriously distorted and contains a large number of harmonics, which not only reduces the power factor of the input circuit, but also affects the common Power system produces pollution, causing circuit failure