CN218449856U

CN218449856U - Lightning protection low pass active filter

Info

Publication number: CN218449856U
Application number: CN202221989727.3U
Authority: CN
Inventors: 聂慧芳; 刘亚轩
Original assignee: Luoyang Longsheng Technology Co Ltd
Current assignee: Luoyang Longsheng Technology Co Ltd
Priority date: 2022-07-29
Filing date: 2022-07-29
Publication date: 2023-02-03
Anticipated expiration: 2032-07-29

Abstract

The utility model discloses a lightning protection low pass active filter, it includes power input end, operational amplifier N1 and power output end, transient suppression diode V1, first filtering unit are connected in parallel between positive, the negative input end of power, first filtering unit is established ties by resistance R1 and electric capacity C1 and is constituteed, second filtering unit is established ties by resistance R2 and electric capacity C2 and is constituteed, resistance R2 one end is connected between resistance R1 and electric capacity C1, electric capacity C2 one end is connected with the negative input end of power; the inverting input end of the operational amplifier N1 is connected between the resistor R2 and the capacitor C2 through the resistor R3, the output end of the operational amplifier N1 is connected with the inverting input end through the capacitor C3 and is connected between the resistor R2 and the capacitor C2 through the resistor R4, the positive power supply is connected with the first voltage, the negative power supply end is grounded, the non-inverting input end is connected with the negative input end of the power supply and the negative output end of the power supply and is grounded, and the output end of the non-inverting input end is connected with the positive output end of the power supply. The utility model discloses both satisfied automatic tracking compensation dynamic harmonic, had the wave filter application scenario of lightning protection function simultaneously again concurrently.

Description

Lightning protection low pass active filter

Technical Field

The utility model belongs to the technical field of the power technique and specifically relates to a lightning protection low pass active filter is related to.

Background

In the application of power supply technology, an EMI filter is very dependent, and an EMI filter commonly used in power supply products is a passive filter. The passive filter is a filter circuit formed by the combination design of an inductor, a capacitor and a resistor, and when the passive filter is applied to a power supply circuit, certain harmonic wave or multiple harmonic waves can be filtered by using the tuning principle of the inductor and the capacitor so as to reduce the injection of interference signals into a power grid. However, passive filters also have significant application drawbacks: the filtering capability of the harmonic wave is limited, and only the harmonic wave with a specific frequency can be filtered, and simultaneously, the amplification of the rest subharmonic waves can be caused, and the harmonic wave can easily generate resonance with other filter circuits.

In the conventional EMI filter type, there is an active filter in addition to a passive filter. Such active filters require an externally supplied power source to actively compensate for the harmonics of the main circuit. Compared to passive filters, active filters have two distinct advantages: 1. the filter characteristic of the active filter is not influenced by the system impedance, so that the danger of resonance with the system impedance can be eliminated; 2. the active filter can overcome the defect that the traditional passive filter can only fixedly compensate harmonic waves, and can realize the function of automatically tracking and compensating dynamically changed harmonic waves.

In the current information era, electronic and electrical equipment is more and more precise, the requirements of working environment are more and more strict, and the transient overvoltage of thunder and lightning and large-scale electrical equipment can intrude into the electronic and electrical equipment through circuits such as a power supply, an antenna, radio signal transceiving equipment and the like, so that the equipment or components are damaged, transmitted or stored data is interfered or lost, and even the electronic equipment generates misoperation or temporary paralysis, system pause and data transmission interruption.

Disclosure of Invention

For the problem that the EMI lightning protection filter filtering harmonic ability that exists is limited among the above-mentioned prior art of solution, and easily takes place the resonance with other filter circuit, the utility model aims at providing a simple structure, lightning protection low pass active filter that the practicality is strong.

In order to achieve the purpose, the utility model adopts the following technical scheme:

a lightning protection low-pass active filter comprises a power input end, an operational amplifier N1 and a power output end, wherein a transient suppression diode V1 and a first filtering unit are connected in parallel between the positive input end and the negative input end of a power supply, the first filtering unit is formed by connecting a resistor R1 and a capacitor C1 in series, the second filtering unit is formed by connecting a resistor R2 and a capacitor C2 in series, one end of the resistor R2 is connected between the resistor R1 and the capacitor C1, and one end of the capacitor C2 is connected with the negative input end of the power supply; the inverting input end of the operational amplifier N1 is connected between the resistor R2 and the capacitor C2 through the resistor R3, the output end of the operational amplifier N1 is connected with the inverting input end through the capacitor C3 and is connected between the resistor R2 and the capacitor C2 through the resistor R4, the positive power supply is connected with the first voltage, the negative power supply is grounded, the non-inverting input end of the operational amplifier N1 is connected with the negative input end of the power supply and the negative output end of the power supply and is grounded, and the output end of the operational amplifier N1 is connected with the positive output end of the power supply.

Due to the adoption of the technical scheme, the utility model discloses have following superiority:

this lightning protection low pass active filter, its simple structure, reasonable in design, components and parts use less, and the cost of manufacture is low, and expansibility is strong, has both satisfied automatic tracking compensation dynamic harmonic, has the filter application scenario of lightning protection function simultaneously again concurrently, has extensive application prospect in electron electrical equipment application field and high accuracy automated production field.

Drawings

Fig. 1 is a schematic diagram of the lightning protection low-pass active filter of the present invention.

Detailed Description

The technical solution of the present invention will be further described in detail with reference to the accompanying drawings and examples.

As shown in fig. 1, the lightning protection low-pass active filter includes a power input terminal, an operational amplifier N1 and a power output terminal, a transient suppression diode V1 and a first filtering unit are connected in parallel between a positive input terminal VIN + and a negative input terminal VIN-, the first filtering unit is formed by connecting a resistor R1 and a capacitor C1 in series, the second filtering unit is formed by connecting a resistor R2 and a capacitor C2 in series, one end of the resistor R2 is connected between the resistor R1 and the capacitor C1, and one end of the capacitor C2 is connected with the negative input terminal VIN-; the operational amplifier N1 is characterized IN that an inverting input end (IN-) is connected between a resistor R2 and a capacitor C2 through a resistor R3, an output end (OUT) is connected with the inverting input end (IN-) through a capacitor C3 and connected between the resistor R2 and the capacitor C2 through a resistor R4, a positive power supply is connected with a first voltage +5V, a negative power supply end is grounded +5VG, an inverting input end (IN +) is connected with a negative power input end VIN-, a negative power output end VOUT-and is grounded, and the output end (OUT) is connected with a positive power output end VOUT +.

Preferably, the operational amplifier N1 is XL158 or SGM8040-2YS8G/TR.

The utility model discloses lightning protection low pass active filter's theory of operation does: when the circuit works normally, the transient suppression diode V1 is in a cut-off state (high-resistance state), and the normal work of the circuit is not influenced; when the circuit is in abnormal overvoltage and reaches the breakdown voltage of the circuit, the transient suppression diode V1 is rapidly changed from a high-resistance state to a low-resistance state, a low-impedance conduction path is provided for instant current, and the abnormal high voltage is clamped in a safe voltage level, so that the back-end circuit is protected; when the abnormal overvoltage disappears, the circuit is restored to a high-resistance state, and the circuit works normally.

An RC filter circuit aiming at high-frequency interference signals on a line is built in front of the operational amplifier N1, the operational amplifier N1 detects and extracts harmonic components of load current, then the harmonic components are sent to an internal IGBT through a PWM signal, and an inverter is controlled to generate a current which is equal to the load harmonic in magnitude and opposite in direction and inject the current into a power grid to compensate harmonic current, so that a filtering function is realized.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A lightning protection low pass active filter is characterized in that: the transient suppression circuit comprises a power supply input end, an operational amplifier N1 and a power supply output end, wherein a transient suppression diode V1 and a first filtering unit are connected in parallel between the positive input end and the negative input end of the power supply, the first filtering unit is formed by connecting a resistor R1 and a capacitor C1 in series, the second filtering unit is formed by connecting a resistor R2 and a capacitor C2 in series, one end of the resistor R2 is connected between the resistor R1 and the capacitor C1, and one end of the capacitor C2 is connected with the negative input end of the power supply; the inverting input end of the operational amplifier N1 is connected between the resistor R2 and the capacitor C2 through the resistor R3, the output end of the operational amplifier N1 is connected with the inverting input end through the capacitor C3 and is connected between the resistor R2 and the capacitor C2 through the resistor R4, the positive power supply is connected with the first voltage, the negative power supply is grounded, the non-inverting input end of the operational amplifier N1 is connected with the negative input end of the power supply and the negative output end of the power supply and is grounded, and the output end of the operational amplifier N1 is connected with the positive output end of the power supply.

2. The lightning protection low pass active filter according to claim 1, wherein: the model of the operational amplifier N1 is XL158 or SGM8040-2YS8G/TR.