Anti-electromagnetic-resistance high-power system power supply

Abstract

The invention relates to an anti-electromagnetic-resistance high-power system power supply. The output end of an EMI (Electro Magnetic Interference) filtering unit is connected with a rectifying unit; a first PFC (Power Factor Correction) circuit and a second PFC circuit are connected to the output end of the rectifying unit in a parallel way; the output end of the first PFC circuit and the output end of the second PFC circuit are connected with an energy storage unit; the energy storage unit is connected with the output end through a full-bridge soft switch; a jitter frequency unit is connected with a PFC control circuit; the PFC control circuit is connected with the first PFC circuit and the second PFC circuit; the jitter frequency unit is also connected with a full-bridge control circuit; the full-bridge control circuit is connected with a delay unit; and the delay unit is connected to the full-bridge soft switch. The PFC circuit are set into two paths, so that the current of a power circuit is halved, and di / dt is reduced; the PFC control circuit is provided with the jitter frequency unit, therefore the spectral bandwidth is extended by diffusing the fundamental frequency, the peak energy of the EMI is reduced, the waveform change of the radiation EMI is gentle, the frequency range of EMI filtering is reduced, an EMI filtering circuit is simplified, the EMI inductance value is reduced and the overall efficiency is improved.

Description

technical field [0001] The invention relates to an anti-electromagnetic interference high-power system power supply. Background technique [0002] At present, most of the high-power system power supply circuit adopts a single-channel PFC circuit. The mains input passes through an EMI (electromagnetic interference) filter, and is converted into a half-wave through a rectifier bridge. The BOOST is raised to about 400V through the PFC circuit. The output of the PFC circuit It is an energy storage capacitor, and then converted to the DC voltage required by the user through a first-stage DC-DC circuit. [0003] The traditional PFC circuit consists of an inductor, a MOS tube and a diode. Because all power needs to pass through the inductor in one cycle, the PFC inductor has a large volume, which is not conducive to PCB layout and production; because all power needs to pass through the MOS tube in each cycle, the di / dt is very large, and a 2000W system power supply For example, ...

AI Technical Summary

Problems solved by technology

Because all power needs to pass through the inductor in one cycle, the PFC inductor has a large volume, which is not conducive to PCB layout and production; because all power needs to pass through the MOS tube in each cycle, the di / dt is very large, and a 2000W system power supply For example, the di / dt generated per cycle is 24A / 30ns; at the same time, the power conversion adopts a hard-switching DC-DC circuit, and the voltage when the MOS tube is turned off in each cycle is 400V, and the generated dv / dt is 400V / 50ns

Because of the large di / dt and dv / dt, the EMI of the high-power system power supply becomes a serious problem. It is necessary to add multi-stage EMI filters and shielding measures to increase the cost and reduce the efficiency of the whole machine

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