Lightning-proof and impact-proof filter circuit for airborne equipment

Abstract

The utility model provides a lightning protection and impact protection filter circuit for airborne equipment, which relates to the technical field of lightning protection and impact protection filtering, and comprises a lightning protection and impact protection filter assembly, and the lightning protection and impact protection filter assembly comprises a lightning protection and impact protection circuit, an impact protection circuit and a filter circuit. The anti-thunder and anti-impact circuit, the anti-impact circuit and the filter circuit are connected in sequence, the input end of the anti-thunder and anti-impact filter assembly is set as a lightning stroke input end, and the output end of the anti-thunder and anti-impact filter assembly is set as a lightning stroke output end. According to the utility model, the transient suppression diode D1 is connected in parallel between the positive wire and the negative wire to prevent lightning stroke interference of the positive wire to the negative wire; the suppression value of the impact current is determined by the resistor R3 of the anti-impact circuit, the working time of the resistor R3 is determined by the capacitor C1 and the capacitor C2, the MOS tube Q1 is conducted to complete the impact current protection function after the resistor R3 finishes working, and the lightning surge is prevented from interfering with the integrated lightning protection device of the filter assembly through the arrangement of the lightning and impact protection circuit, the anti-impact circuit and the filter circuit.

Description

Technical Field

[0001] This utility model relates to the field of lightning protection and shock protection filtering technology, specifically a lightning protection and shock protection filtering circuit for airborne equipment. Background Technology

[0002] The instantaneous current surge caused by the charging of the downstream capacitor at the moment the switch is closed can cause the upstream protection circuit of the airborne equipment to think that the downstream stage has a short circuit, resulting in abnormal operation of the equipment. During operation, the airborne equipment may be subject to lightning surge interference. This filter component integrates a lightning protection device.

[0003] Existing airborne equipment may experience lightning surge interference during operation. The filter circuit integrates lightning protection devices. Therefore, a lightning and surge protection filter circuit for airborne equipment is designed to protect against lightning and surges. Utility Model Content

[0004] Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this utility model provides a lightning and surge protection filter circuit for airborne equipment, which solves the problem that existing airborne equipment may experience lightning surge interference during operation, and the integrated lightning protection device in the filter circuit is not suitable for such interference.

[0006] Technical solution

[0007] To achieve the above objectives, this utility model provides the following technical solution: a lightning and shock protection filter circuit for airborne equipment, comprising a lightning and shock protection filter component, wherein the lightning and shock protection filter component comprises a lightning and shock protection circuit, a shock protection circuit, and a filter circuit.

[0008] The lightning protection and shock protection circuit, the shock protection circuit, and the filter circuit are connected in sequence. The input terminal of the lightning protection and shock protection filter component is set as the lightning strike input terminal, and the output terminal of the lightning protection and shock protection filter component is set as the lightning strike output terminal.

[0009] The input terminal of the lightning protection and shock protection circuit is connected to the lightning strike input terminal, the output terminal of the lightning protection and shock protection circuit is connected to the shock protection circuit input terminal, and the output terminal of the filter circuit is connected to the lightning strike output terminal.

[0010] Preferably, the lightning protection and surge protection circuit includes transient suppression diodes D1, D2, and D3, wherein:

[0011] The transient suppression diode D1 is connected in parallel with the positive and negative lines of the lightning input terminal. The first terminals of the transient suppression diodes D2 and D3 are both connected to the chassis ground. The second terminal of the transient suppression diode D2 is connected to the positive line of the lightning input terminal, and the second terminal of the transient suppression diode D3 is connected to the positive line of the lightning input terminal.

[0012] Preferably, the shock-resistant circuit includes capacitor C1, capacitor C2, resistor R1, resistor R2, resistor R3, MOSFET Q1, and diode D4, wherein:

[0013] The positive terminal of the lightning protection and surge protection circuit is connected to the first terminal of resistor R2, the negative terminal of the lightning protection and surge protection circuit is connected to the first terminal of resistor R3, the second terminal of resistor R2 is connected to the second terminal of resistor R3, capacitors C1 and C2 are respectively connected between the first terminal and the second terminal of resistor R2, the first terminal of resistor R2 is connected to the cathode of transient suppression diode D1, the second terminal of resistor R2 is connected to the anode of transient suppression diode D1, the anode of transient suppression diode D1 is connected to the gate of MOSFET Q1, the cathode of transient suppression diode D1 is connected to the source of MOSFET Q1, the drain of MOSFET Q1 is connected to the positive terminal of the lightning protection and surge protection circuit input through resistor R1, the first terminal of resistor R3 is set as the negative terminal of the surge protection circuit output, and the connection between resistor R1 and the drain of MOSFET Q1 is set as the positive terminal of the surge protection circuit output.

[0014] Preferably, the filtering circuit includes a first-stage filtering circuit and a second-stage filtering circuit. The first-stage filtering circuit includes a differential-mode capacitor CX1, a differential-mode capacitor CX2, a common-mode capacitor CY1, a common-mode capacitor CY2, and a common-mode inductor L1. The second-stage filtering circuit includes a common-mode inductor L2, a common-mode capacitor CY3, and a common-mode capacitor CY4, wherein:

[0015] The input terminal of the common-mode inductor L1 is connected to the output terminal of the anti-shock circuit. The positive and negative terminals of the input terminal of the common-mode inductor L1 are connected to the differential-mode capacitor CX1. The positive and negative terminals of the output terminal of the common-mode inductor L1 are connected to the differential-mode capacitor CX2. The positive terminal of the output terminal of the common-mode inductor L1 is connected to the positive terminal of the common-mode capacitor CY1. The positive terminal of the output terminal of the common-mode inductor L1 is connected to the first terminal of the common-mode capacitor CY1. The negative terminal of the output terminal of the common-mode inductor L1 is connected to the first terminal of the common-mode capacitor CY2. The first terminals of both the common-mode capacitor CY1 and the first terminal of the common-mode capacitor CY2 are connected to the chassis ground.

[0016] The input terminal of the common mode inductor L2 is connected to the output terminal of the common mode inductor L1. The positive terminal of the output terminal of the common mode inductor L2 is connected to the first terminal of the common mode capacitor CY3. The negative terminal of the output terminal of the common mode inductor L2 is connected to the first terminal of the common mode capacitor CY4. The second terminals of the common mode capacitors CY3 and CY4 are both connected to the chassis ground. The output terminal of the common mode inductor L2 is connected to the lightning strike output terminal.

[0017] Beneficial effects

[0018] This utility model provides a lightning and shock protection filtering circuit for airborne equipment. It has the following beneficial effects:

[0019] 1. In this utility model, after transient suppression diodes D2 and D3 are both soldered to the chassis ground, the other ends of transient suppression diodes D2 and D3 are soldered to the positive and negative lines respectively to prevent the positive and negative lines from interfering with the chassis by lightning strikes. Then, transient suppression diode D1 is connected in parallel between the positive and negative lines to prevent the positive line from interfering with the negative line by lightning strikes.

[0020] In this invention, capacitor C1, capacitor C2, resistor R1, resistor R2, and MOSFET Q1 are connected sequentially to the positive terminal of the anti-surge circuit. Then, they are connected in series with resistor R3 and then in parallel to form the anti-surge circuit. Resistor R3 determines the suppression value of the surge current, and capacitors C1 and C2 determine the working time of resistor R3. After resistor R3 has finished working, MOSFET Q1 turns on to complete the surge current protection function.

[0021] In this invention, the lightning protection and surge protection circuit, the surge protection circuit, and the filter circuit are designed to prevent lightning surge interference from the integrated lightning protection device. Attached Figure Description

[0022] Figure 1 This is a circuit diagram of a lightning protection and shockproof filtering circuit for airborne equipment according to the present invention. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] like Figure 1 As shown, the lightning and shock protection filtering circuit for airborne equipment provided by this utility model includes a lightning and shock protection filtering component, which includes a lightning and shock protection circuit, a shock protection circuit, and a filtering circuit. The lightning and shock protection circuit, the shock protection circuit, and the filtering circuit are connected in sequence. The input terminal of the lightning and shock protection filtering component is set as a lightning strike input terminal, and the output terminal of the lightning and shock protection filtering component is set as a lightning strike output terminal. The input terminal of the lightning and shock protection circuit is connected to the lightning strike input terminal, the output terminal of the lightning and shock protection circuit is connected to the shock protection circuit input terminal, and the output terminal of the filtering circuit is connected to the lightning strike output terminal.

[0025] The lightning protection and surge protection circuit includes transient suppression diodes D1, D2, and D3. Transient suppression diodes D2 and D3 are soldered to the chassis ground. The other ends of transient suppression diodes D2 and D3 are soldered to the positive and negative lines respectively to prevent lightning interference from the positive and negative lines to the chassis. Transient suppression diode D1 is then connected in parallel between the positive and negative lines to prevent lightning interference from the positive line to the negative line.

[0026] The surge protection circuit includes capacitor C1, capacitor C2, resistors R1, R2, and R3, MOSFET Q1, and diode D4. The positive terminal is connected in sequence to capacitors C1, C2, R1, R2, and MOSFET Q1. Then, it is connected in series with resistor R3 and then in parallel with the negative terminal to form the surge protection circuit. Resistor R3 determines the surge current suppression value, and capacitors C1 and C2 determine the working time of resistor R3. After resistor R3 has finished working, MOSFET Q1 conducts to complete the surge current protection function.

[0027] The filter circuit includes a primary filter circuit and a secondary filter circuit. The primary filter circuit includes differential-mode capacitor CX1, differential-mode capacitor CX2, common-mode capacitor CY1, common-mode capacitor CY2, and common-mode inductor L1. The secondary filter circuit includes common-mode inductor L2, common-mode capacitor CY3, and common-mode capacitor CY4. The filter circuit is divided into two stages. In the first stage, differential-mode capacitor CX1 is connected in parallel between the positive and negative lines. Then, common-mode inductor L1 is soldered. Next, differential-mode capacitor CX2 is soldered between the positive and negative lines. Finally, common-mode capacitors CY1 and CY2 are soldered to the positive and negative lines and then grounded respectively. In the second stage, common-mode inductor L2 is soldered first. Then, common-mode capacitors CY3 and CY4 are soldered to the positive and negative lines and then grounded respectively.

[0028] By incorporating lightning and surge protection circuits, surge protection circuits, and filtering circuits, interference from lightning surges is avoided. This filtering component integrates lightning protection devices and meets the Air Force requirements of JB151B-2003 "Electromagnetic Emissions and Sensitivity Requirements for Equipment and Subsystems," making it suitable for applications where time and economic costs are critical.

[0029] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An on-board equipment lightning and surge protection filter circuit, characterized by: The lightning protection and surge protection filter assembly comprises a lightning protection and surge protection circuit, a surge protection circuit and a filter circuit; The lightning protection and surge protection circuit, the surge protection circuit and the filter circuit are connected in sequence, the input end of the lightning protection and surge protection filter assembly is set as a lightning input end, and the output end of the lightning protection and surge protection filter assembly is set as a lightning output end; The input end of the lightning protection and surge protection circuit is connected to the lightning input end, the output end of the lightning protection and surge protection circuit is connected to the input end of the surge protection circuit, and the output end of the filter circuit is connected to the lightning output end.

2. The lightning and surge protection filter circuit for onboard equipment according to claim 1, characterized in that: The lightning protection and surge protection circuit comprises transient suppression diodes D1, D2 and D3, wherein: The transient suppression diode D1 is connected in parallel with the positive and negative lines of the lightning input end, the first ends of the transient suppression diodes D2 and D3 are connected to the ground of the shell, the second end of the transient suppression diode D2 is connected to the positive line of the lightning input end, and the second end of the transient suppression diode D3 is connected to the positive line of the lightning input end.

3. The lightning and surge protection filter circuit for onboard equipment according to claim 2, characterized in that: The surge protection circuit comprises capacitors C1 and C2, resistors R1, R2 and R3, a MOS tube Q1 and a diode D4, wherein: The positive end of the output end of the lightning protection and surge protection circuit is connected to the first end of the resistor R2, the negative end of the output end of the lightning protection and surge protection circuit is connected to the first end of the resistor R3, the second ends of the resistors R2 and R3 are connected, the capacitors C1 and C2 are respectively connected between the first end of the resistor R2 and the second end of the resistor R2, the first end of the resistor R2 is connected to the cathode of the transient suppression diode D1, the second end of the resistor R2 is connected to the anode of the transient suppression diode D1, the anode of the transient suppression diode D1 is connected to the gate of the MOS tube Q1, the cathode of the transient suppression diode D1 is connected to the source of the MOS tube Q1, the drain of the MOS tube Q1 is connected to the positive end of the input end of the lightning protection and surge protection circuit through the resistor R1, the first end of the resistor R3 is set as the negative end of the output end of the surge protection circuit, and the connection position of the resistor R1 and the drain of the MOS tube Q1 is set as the positive end of the output end of the surge protection circuit.

4. The lightning and surge protection filter circuit for onboard equipment according to claim 3, characterized in that: The filter circuit comprises a first-stage filter circuit and a second-stage filter circuit, the first-stage filter circuit comprises differential mode capacitors CX1 and CX2, common mode capacitors CY1 and CY2 and a common mode inductor L1, and the second-stage filter circuit comprises a common mode inductor L2, a common mode capacitor CY3 and a common mode capacitor CY4, wherein: The input end of the common mode inductor L1 is connected to the output end of the surge protection circuit, the positive and negative ends of the input end of the common mode inductor L1 are connected to the differential mode capacitor CX1, the positive and negative ends of the output end of the common mode inductor L1 are connected to the differential mode capacitor CX2, the positive end of the output end of the common mode inductor L1 is connected to the positive end of the common mode capacitor CY1, the positive end of the output end of the common mode inductor L1 is connected to the first end of the common mode capacitor CY1, the negative end of the output end of the common mode inductor L1 is connected to the first end of the common mode capacitor CY2, and the first ends of the common mode capacitors CY1 and CY2 are connected to the ground of the shell; The common-mode inductor L2 input end is connected with the common-mode inductor L1 output end, the positive terminal of the common-mode inductor L2 output end is connected with the first terminal of the common-mode capacitor CY3, the negative terminal of the common-mode inductor L2 output end is connected with the first terminal of the common-mode capacitor CY4, the second terminal of the common-mode capacitor CY3 and the second terminal of the common-mode capacitor CY4 are both connected with the case ground, and the common-mode inductor L2 output end is connected with the lightning stroke output end.

Images