Output filtering circuit of high-power low-voltage large-current high-frequency switch power supply device

Abstract

The invention provides an output filtering circuit of a high-power low-voltage large-current high-frequency switch power supply device, which comprises an inductance, a capacitor bank, an anode copper bar and a cathode copper bar. The capacitor bank (CZ) consists of N capacitor bars; the capacitor bars have the same structures; each capacitor bar comprises M electrolytic capacitors; N is more than or equal to 1; M is more than or equal to 2; and each electrolytic capacitor is respectively and independently connected to the anode copper bar or the cathode copper bar through a group of lead wires. In the invention, a total current of a capacitance branch in the filtering circuit is shunted by a plurality of electrolytic capacitors so as to greatly reduce ripple waves generated when the current flows parasitic inductances in the electrolytic capacitance branches and achieving a good filtering effect; and compared with a structure that only one large capacitor is used or a plurality of large capacitors are connected in parallel, a structure of using a plurality of capacitor bars has a good heat dissipating effect and small volume. The output filtering circuit is suitable to be used as the output filtering circuit of industrial power supply devices for electrolysis, electroplating and the like or other high-power high-frequency switch power supplies which need a low-voltage large-current output.

Description

technical field [0001] The invention relates to the technical field of output filtering of a high-power, high-frequency switching power supply with low-voltage, high-current output, in particular to an output filtering circuit of a high-power, low-voltage, high-current, high-frequency switching power supply device suitable for electrolysis, electroplating and other industrial fields. Background technique [0002] High-frequency switching power supply is more and more widely used in industrial production. For example, as the core part of electrochemical industrial power supply equipment such as electrolysis and electroplating, high-frequency switching power supply generally needs to output DC power of 6~30V and 1000A or more. Moreover, in order to improve the process quality, the lower the ripple of the output voltage and current, the better, and even some occasions require the ripple of the voltage and current to be less than 1%, which is a great problem for the design of the...

AI Technical Summary

Problems solved by technology

Because the output current of the power supply is very large, the filter inductance is generally composed of a copper bar passing through the magnetic ring. At this time, the copper bar is equivalent to the coil of the inductor, and the number of turns is generally less than one turn. This kind of inductance is very small; it can pass through and multiple The magnetic ring is used to increase the inductance, but due to the limited space of the power supply device, the magnetic rings that can be connected in parallel are limited, so the total inductance is relatively small

At the same time, the filter capacitor, the connection between the filter capacitor and the output busbar, and the output wire have parasitic inductance. Compared with the filter inductance, the value of these parasitic inductance is very considerable, which makes the high-frequency pulse large current pass through the LC filter. The parasitic inductance between the capacitor and the filter capacitor and the output busbar produces a large voltage ripple, which makes the output voltage and current ripple of the power supply very large

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