CN217607701U

CN217607701U - Novel direct-current power supply filter

Info

Publication number: CN217607701U
Application number: CN202220453218.2U
Authority: CN
Inventors: 王永怀; 王科伟; 秦鹏; 陈伟; 邢先锋
Original assignee: Xi'an Ruijing Microelectronic Co ltd
Current assignee: Xi'an Ruijing Microelectronic Co ltd
Priority date: 2022-03-04
Filing date: 2022-03-04
Publication date: 2022-10-18
Anticipated expiration: 2032-03-04

Abstract

The utility model discloses a novel direct current power supply filter, which comprises a primary filtering part and a secondary filtering part, wherein the primary filtering part consists of C1, T and C6 to form a pi-type filtering circuit, and the secondary filtering part consists of Y capacitors C2, C3, C4 and C5 to form a Y capacitor filtering circuit; compared with the prior art, the utility model the advantage lie in: the interference is filtered by adopting a two-stage filter circuit, different circuit modes are adopted for gradual expansion, and the filter specifically has two circuit modes of a pi-type filter circuit and a Y-type capacitor filter circuit to realize a better filter function.

Description

Novel direct-current power supply filter

Technical Field

The utility model relates to a control technical field specifically indicates a novel DC power supply filter.

Background

With the rapid development of modern science and technology, electronic, power electronic and electrical equipment are more and more widely applied, and high-density and wide-spectrum electromagnetic signals generated in the operation of the electronic, power electronic and electrical equipment fill the whole space to form a complex electromagnetic environment. The complex electromagnetic environment requires higher electromagnetic compatibility for electronic devices and power supplies. Accordingly, techniques for suppressing electromagnetic interference are also receiving increasing attention.

The method is characterized in that a power supply of electronic equipment, an artificial EMI interference source, natural interference sources such as a switch discharge phenomenon and space electric interference noise are searched, and electronic circuit components can generate thermal noise when working. These electromagnetic interference noises, by way of radiative and conductive coupling, can affect the proper operation of various electronic devices operating in this environment. On the other hand, electronic devices also generate various electromagnetic interference noises during operation. Various types of regulated power supplies are also electromagnetic interference sources. In a linear voltage-stabilized power supply, electromagnetic interference is also caused by unidirectional pulsating current formed by rectification; switching power supplies are increasingly used in modern electronic devices, but because they are switched during power conversion, they are inherently a strong source of EMI noise, which generates EMI noise having both a wide frequency range and high intensity. These electromagnetic interference noises also contaminate the electromagnetic environment by radiation and conduction, thereby affecting the proper operation of other electronic devices. For electronic equipment, when EMI noise affects an analog circuit, the signal-to-noise ratio of signal transmission may deteriorate, and in a serious case, a signal to be transmitted may be submerged by the EMI noise and cannot be processed. When EMI noise affects digital circuits, logic relationship errors can be caused, resulting in erroneous results. The power supply device includes a driving circuit, a control circuit, a protection circuit, an input/output level detection circuit, and the like in addition to a power conversion circuit, and thus the circuit is complicated. These circuits are mainly composed of general-purpose or application-specific integrated circuits, and when malfunction occurs due to electromagnetic interference, the power supply stops operating, and the electronic apparatus cannot operate normally. The power grid noise filter can effectively prevent the power supply from generating misoperation due to external electromagnetic noise interference. EMI noise entering from the power input terminal, a part of which may appear at the power output terminal, may generate an induced voltage in a load circuit of the power supply, which may cause malfunction of the circuit or interference with a transmission signal in the circuit. These problems can also be prevented by noise filters, and in this background, we have designed this new type of dc power filter.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is overcome above technical defect, provide a novel DC power supply filter, adopt two-stage filter circuit filtering interference, adopt different circuit mode to expand step by step moreover, specifically possess pi type filter circuit, two kinds of circuit mode of Y electric capacity filter circuit two-stage and realize better filtering capability.

In order to solve the technical problem, the utility model provides a technical scheme does: a novel direct-current power supply filter comprises a primary filtering part and a secondary filtering part, wherein the primary filtering part consists of C1, T and C6 to form a pi-type filtering circuit, and the secondary filtering part consists of Y capacitors C2, C3, C4 and C5 to form a Y capacitor filtering circuit;

the positive electrode of the input end of the filter power supply is connected with the end 1 of the C1 input of the pi-type filter circuit, the negative electrode of the input end of the filter power supply is connected with the end 2 of the C1 input of the pi-type filter circuit, the end 1 of the C1 input of the pi-type filter circuit and the end 1 of the inductor T are connected, the end 2 of the C1 capacitor of the pi-type filter circuit, the end 2 of the inductor T and the end 2 of the C3 capacitor are connected, the end 2 of the C2 capacitor of the filter C2 and the end 1 of the C3 capacitor are connected with the ground end of the shell, the end 1 of the C6 input of the pi-type filter circuit, the end 3 of the inductor T and the end 1 of the C4 capacitor are connected, the end 2 of the C6 capacitor of the pi-type filter circuit, the end 4 of the inductor T and the end 2 of the C5 capacitor are connected, the end 2 of the C4 capacitor of the filter C4, the end 1 of the C5 capacitor and the ground end of the shell are connected, the positive electrode of the output end of the filter circuit is connected with the end 1 of the capacitor C6, and the negative electrode of the filter circuit is connected with the end 2 of the capacitor C6.

As an improvement, the inductor is wound by adopting a plurality of strands of enameled wires, and is wound by adopting 3 strands of enameled wires with the diameter of 0.25, so that the current-carrying efficiency is improved by increasing the current-conducting area, the skin effect of interference signals is reduced and inhibited, the conductivity is enhanced, the reliability of the product is improved, and the heating is reduced.

As an improvement, the whole body adopts electromagnetic shielding, the electromagnetic shielding is isolated from the space, the internal and external electromagnetic contact is thoroughly separated, an independent area is formed, the electromagnetic shielding type electromagnetic shielding device is not influenced by external interference, and radiation interference and induction interference are more reliably eliminated.

Compared with the prior art, the utility model the advantage lie in: the specific filter adopts multiple circuits, multiple modes and multiple levels to realize filtering, in addition, in the implementation process, other means are also adopted to improve the performance, the anti-interference performance is enhanced, the reliability is improved, particularly, the interference is mostly conducted by radiation, the signal frequency is high, the skin effect is generated, the lead is easy to heat along the lead transmission, the conductive performance is reduced, and the current-carrying effect is achieved, so that the anti-interference inductance coil is wound by adopting a plurality of strands of enameled wires, and is specifically manufactured by adopting 3 strands of enameled wires with the diameter of 0.25, and the skin effect is reduced.

In addition, the space isolation shielding is adopted to form an independent circuit space, so that the interference of static electricity and a magnetic field cannot be caused to the filter circuit, and the electromagnetic interference is thoroughly cut off from a physical space. The whole control circuit is sealed by a metal shell capable of shielding electromagnetic interference, so that isolation and shielding are completed.

Drawings

Fig. 1 is a schematic circuit block diagram of the novel dc power filter of the present invention.

Fig. 2 is a circuit diagram of the novel dc power filter of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

A novel direct-current power supply filter comprises a primary filtering part and a secondary filtering part, wherein the primary filtering part consists of C1, T and C6 to form a pi-type filtering circuit, and the secondary filtering part consists of Y capacitors C2, C3, C4 and C5 to form a Y capacitor filtering circuit;

The inductor is wound by adopting a plurality of strands of enameled wires, and 3 strands of enameled wires with the diameter of 0.25 are used for winding.

The whole body adopts electromagnetic shielding, is isolated from space, adopts the method of completely isolating the electromagnetic connection between the inside and the outside to form an independent area, and is not interfered and influenced by the outside.

The DC power supply filter is a passive low-pass filter, which transmits the DC power to the back-stage power supply without attenuation, greatly attenuates the noise introduced with the DC power, and effectively suppresses the noise generated by the power supply equipment and prevents the noise from entering the DC power supply to interfere other electronic equipment. The structure is a passive network, is suitable for a direct current power supply and has bidirectional inhibition performance. The noise suppressor is inserted between a direct current power supply and power supply equipment, namely a blocking barrier is added between the noises of the direct current power supply and the power supply equipment, so that the noise suppressor plays a role in bidirectional noise suppression, and can be widely applied to various electronic equipment.

The utility model discloses DC power supply filter comprises multistage filter circuit, adopts multiple mode to carry out multi-level interference filtering. The specific circuit part of the device is explained as follows:

an input filter circuit: the primary filtering is a pi-type filtering network consisting of C1, L and C6, which mainly suppresses electromagnetic noise and clutter signals of an input power supply, prevents interference on the power supply, and simultaneously prevents high-frequency clutter generated by the power supply from interfering with the power supply. The second filtering is performed again by the Y capacitors C2, C3, C4, and C5. Therefore, the purpose of filtering is achieved, and the function of filtering is achieved.

Specifically, C1, T and C6 form a primary filtering part to form a pi-type filtering circuit to finish primary filtering, Y capacitors C2, C3, C4 and C5 form a secondary filtering part to form capacitor branches to finish secondary filtering, and the whole filter has two-stage filtering and multi-level anti-interference filtering functions.

It should be noted that, the specific filter adopts multiple circuits, multiple modes and multiple levels to realize filtering, and in the implementation process, other measures are also adopted to improve the performance, enhance the anti-interference performance and improve the reliability, especially, the interference is mostly caused by radiation conduction, the signal frequency is high, a skin effect is generated, the wire is easy to heat along the wire transmission, the conductivity is reduced, and the current-carrying effect is achieved, so that the anti-interference inductance coil is wound by adopting a plurality of strands of enameled wires, and is specifically manufactured by adopting 3 strands of enameled wires with the diameter of 0.25, and the skin effect is reduced.

In addition, the space isolation shielding is adopted to form an independent circuit space, so that the electrostatic and magnetic field interference can not be caused to a filter circuit, and the electromagnetic interference can be thoroughly separated from the physical space. The whole control circuit is sealed by a metal shell capable of shielding electromagnetic interference, so that isolation and shielding are completed.

The present invention and its embodiments have been described above, but the description is not limited thereto, and what is shown in the drawings is only one of the embodiments of the present invention, and the actual structure is not limited thereto. In summary, those skilled in the art should understand that they should not be limited to the embodiments described above, and that they can design the similar structure and embodiments without departing from the spirit of the invention.

Claims

1. A novel direct current power supply filter is characterized in that: the filter comprises a primary filter part and a secondary filter part, wherein the primary filter part consists of C1, T and C6 to form a pi-type filter circuit, and the secondary filter part consists of Y capacitors C2, C3, C4 and C5 to form a Y capacitor filter circuit;

the positive electrode of the input end of a filter power supply is connected with the 1 input end C1 of a pi-type filter circuit, the negative electrode of the input end of the filter power supply is connected with the 2 input end C1 of the pi-type filter circuit, the 1 input end C1 of the pi-type filter circuit and the 1 end of an inductor T are connected, the 2 ends C1 and T of the pi-type filter circuit and the 2 ends C3 of the capacitor T are connected, the 2 ends C2 and T of the filter C2 of the capacitor T are connected with the ground end of a shell, the 1 input end C6 of the pi-type filter circuit, the 3 ends of the inductor T and the 1 end C4 of the capacitor T are connected, the 2 ends C6 and T of the pi-type filter circuit and the 2 ends C5 of the capacitor T are connected, the 2 ends C4 and C5 of the filter C4 of the capacitor and the 1 end C5 of the capacitor are connected with the ground end of the shell, the positive electrode of the output end of the filter is connected with the 1 end C6, and the negative electrode of the filter circuit is connected with the 2 end C6 of the output end of the capacitor C6.

2. The novel direct-current power supply filter according to claim 1, characterized in that: the inductor is wound by adopting a plurality of strands of enameled wires, and 3 strands of enameled wires with the diameter of 0.25 are adopted for winding.