A lightning protection filter circuit suitable for airborne windshield washer systems

Abstract

This utility model provides a lightning protection filter circuit suitable for airborne windshield washer systems, relating to the field of power adapter technology. It includes a lightning protection filter device, within which a lightning protection filter circuit is installed. The lightning protection filter circuit comprises a conventional lightning protection filter circuit, a power supply characteristic protection circuit, and a power supply filter protection circuit. These circuits are connected sequentially. An AC input terminal, a signal output terminal, and a power output terminal are respectively arranged around the lightning protection filter device. By integrating the conventional lightning protection filter circuit, the power supply characteristic protection circuit, and the power supply filter protection circuit into a single space, it not only meets the filtering efficiency against high-frequency external interference but also provides protection against indirect and direct lightning strikes, thus satisfying the electromagnetic compatibility requirements of complex electromagnetic environments in aircraft. It can be widely used in the field of complex electromagnetic environments in aviation.

Description

Technical Field

[0001] This utility model relates to the field of power adapter technology, specifically a lightning protection filter circuit suitable for airborne windshield washer systems. Background Technology

[0002] Electromagnetic interference (EMI) generated by airborne motor systems on communication systems is an important consideration, especially in the aviation field. This interference can affect various electronic devices on aircraft, especially navigation and communication systems, thus posing a potential threat to flight safety.

[0003] Existing lightning protection filtering devices for airborne windshield washer systems generally use plastic housings and have not yet undergone targeted filtering treatment in the industry. Electromagnetic interference generated by the switching operation of the motor in the washer system and the high-frequency switching components of the motor control board can cause serious safety hazards such as distortion of communication signals and increased bit error rate. Utility Model Content

[0004] Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this utility model provides a lightning protection filter circuit suitable for airborne windshield washer systems. It solves the serious safety hazards caused by electromagnetic interference from the switching operation of the motor and the high-frequency switching elements of the motor control board in existing washer systems, which can lead to distortion of communication signals and increased bit error rate.

[0006] Technical solution

[0007] To achieve the above objectives, this utility model is implemented through the following technical solution: a lightning protection filter circuit suitable for airborne windshield washer systems, comprising a lightning protection filter device, wherein the lightning protection filter device is provided with a lightning protection filter circuit, and the lightning protection filter circuit comprises a conventional lightning protection filter circuit, a power supply characteristic protection circuit, and a power supply filter protection circuit.

[0008] The lightning protection conventional filter circuit, power supply characteristic protection circuit and power filter protection circuit are connected in sequence, and AC input terminal, signal output terminal and power output terminal are respectively arranged around the lightning protection filter device.

[0009] Preferably, the conventional lightning protection filter circuit includes transient suppression diodes D1, D2, and D3, wherein:

[0010] The two ends of the transient suppression diode D1 are connected in parallel to the two ends of the AC input terminal. The two ends of the transient suppression diode D1 are respectively connected to the first end of the transient suppression diode D2 and the first end of the transient suppression diode D3. The second ends of the transient suppression diode D2 and the second ends of the transient suppression diode D3 are both connected to the chassis ground.

[0011] Preferably, the power supply characteristic protection circuit includes a Schottky diode D4, a voltage adjustment diode D5, a charging capacitor CX1, resistors R1, R2, R3, R4, R5, and R6, a PNP transistor Q1, and a MOSFET Q2, wherein:

[0012] The anode of the Schottky diode D4 is connected to the positive output terminal of the conventional lightning protection filter circuit. The cathode of the Schottky diode D4 is split into two paths. One path of the cathode of the Schottky diode D4 is connected to the first end of resistor R1, and the other path of the cathode of the Schottky diode D4 is connected to the positive input terminal of the power supply filter protection circuit. The second end of resistor R1 is split into two paths. One path of the second end of resistor R1 is connected to the cathode of voltage adjustment diode D5, and the other path of the second end of resistor R1 is connected to resistor R2. The anode of voltage adjustment diode D5 is connected to the negative output terminal of the conventional lightning protection filter circuit.

[0013] The positive terminal of the conventional lightning protection filter circuit is connected to the first terminal of resistor R5. The base of the PNP transistor Q1 is connected to the second terminal of resistor R5 and the first terminal of resistor R6. The second terminal of resistor R6 is connected to the collector of PNP transistor Q1. The collector of PNP transistor Q1 is connected to resistor R2 through resistor R3. The emitter of PNP transistor Q1 is connected to the second terminal of resistor R2.

[0014] The second end of resistor R2 is connected to the gate of MOS transistor Q2, the source of MOS transistor Q2 is connected to the collector of PNP transistor Q, the source and drain of MOS transistor Q2 are respectively connected to the two ends of resistor R4, and the drain of MOS transistor Q2 is connected to the negative input terminal of the power supply filter protection circuit.

[0015] Preferably, the power supply filtering and protection circuit includes feedthrough capacitor CY1, feedthrough capacitor CY2, differential mode inductor L1, differential mode inductor L2, differential mode capacitor CX1, differential mode capacitor CX2, differential mode capacitor CX3, common mode inductor L3, common mode inductor L4, common mode capacitor CY3, common mode capacitor CY4, common mode capacitor CY5, and common mode capacitor CY6, wherein:

[0016] The positive output terminal of the power supply characteristic protection circuit is connected to one end of the feedthrough capacitor CY1, and the negative output terminal of the power supply characteristic protection circuit is connected to one end of the feedthrough capacitor CY2. Both feedthrough capacitors CY1 and CY2 are connected to the chassis ground. The other end of the feedthrough capacitor CY1 is connected to the input terminal of the differential mode inductor L1, and the feedthrough capacitor CY2 is connected to the input terminal of the differential mode inductor L2. The two ends of the differential mode capacitor CX1 are connected to the output terminals of the differential mode inductors L1 and L2, respectively, and the two ends of the differential mode capacitor CX2 are also connected to the output terminals of the differential mode inductors L1 and L2, respectively.

[0017] The output terminal of the differential mode inductor L1 is connected to the positive terminal of the input terminal of the common mode inductor L3, the output terminal of the differential mode inductor L2 is connected to the negative terminal of the input terminal of the common mode inductor L3, the two ends of the differential mode capacitor CX3 are respectively connected to the two ends of the output terminal of the common mode inductor L3, the positive terminal of the output terminal of the common mode inductor L3 is connected to the first terminal of the common mode capacitor CY3, the negative terminal of the output terminal of the common mode inductor L3 is connected to the first terminal of the common mode capacitor CY4, and the second terminals of the common mode capacitors CY3 and CY4 are both connected to the chassis ground.

[0018] The output terminal of the common mode inductor L3 is connected to the input terminal of the common mode inductor L4. The positive terminal of the output terminal of the common mode inductor L4 is connected to the first terminal of the common mode capacitor CY5. The negative terminal of the output terminal of the common mode inductor L4 is connected to the first terminal of the common mode capacitor CY6. The second terminals of the common mode capacitors CY5 and CY6 are both connected to the chassis ground. The output terminal of the common mode capacitor CY5 is set as the power output terminal.

[0019] Beneficial effects

[0020] This invention provides a lightning protection filter circuit suitable for airborne windshield washer systems. It has the following advantages:

[0021] In this invention, the clamping characteristic of the transient suppression diode is used to discharge lightning interference to the ground, thereby improving the system's lightning protection capability.

[0022] In this invention, the reverse connection protection function of the device is achieved by utilizing the unidirectional conductivity of the Schottky diode D4. By controlling the conduction time of the source and gate switches of the MOSFET Q2, the current through the circuit is gradually increased, thereby achieving smooth start-up, effectively suppressing inrush current, and improving the power supply reliability of the system.

[0023] In this invention, the interference is initially absorbed and discharged through the LC filter circuit, thereby improving the filtering efficiency of the system. The feedthrough capacitors CY1 and CY2 adopt an input-output compartment design to improve the high-frequency filtering capability of the filter device.

[0024] In this invention, by integrating a conventional lightning protection filtering circuit, a power supply characteristic protection circuit, and a power supply filtering protection circuit into one space, it not only meets the filtering performance requirements for high-frequency external interference, but also provides protection against indirect and direct lightning strikes, thereby meeting the electromagnetic compatibility requirements of aircraft in complex electromagnetic environments. It can be widely used in the field of complex electromagnetic environments in aviation. Attached Figure Description

[0025] Figure 1 This is a circuit diagram of a lightning protection filter circuit applicable to an airborne windshield washer system according to the present invention.

[0026] Figure 2 This is an external view of a lightning protection filter device suitable for a lightning protection filter circuit in an airborne windshield washer system. Detailed Implementation

[0027] 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.

[0028] As shown in the figure, the present invention provides a lightning protection filter circuit suitable for airborne windshield washer systems. The lightning protection filter device is equipped with a lightning protection filter circuit, which integrates a three-stage filter circuit. The lightning protection filter circuit consists of a conventional lightning protection filter circuit, a power supply characteristic protection circuit, and a power supply filter protection circuit. The conventional lightning protection filter circuit, the power supply characteristic protection circuit, and the power supply filter protection circuit are connected in sequence. An AC input terminal, a signal output terminal, and a power output terminal are respectively arranged around the lightning protection filter device.

[0029] The conventional lightning protection filter circuit consists of transient suppression diodes D1, D2, and D3. The two ends of transient suppression diode D1 are connected in parallel to the two ends of the AC input terminal. The two ends of transient suppression diode D1 are connected to the first terminals of transient suppression diodes D2 and D3, respectively. The second terminals of transient suppression diodes D2 and D3 are both connected to the chassis ground. By utilizing the clamping characteristics of the transient suppression diodes, lightning interference is discharged to the ground, thereby improving the system's lightning protection capability.

[0030] The power supply characteristic protection circuit consists of a Schottky diode D4, a voltage adjustment diode D5, a charging capacitor CX1, resistors R1, R2, R3, R4, R5, and R6, a PNP transistor Q1, and a MOSFET Q2. It utilizes the unidirectional conductivity of the Schottky diode D4 to achieve reverse connection protection, and by controlling the conduction time of the source and gate switches of the MOSFET Q2, it gradually increases the current flowing through the circuit, thereby achieving smooth startup, effectively suppressing inrush current, and improving the power supply reliability of the system.

[0031] The power supply filtering and protection circuit consists of feedthrough capacitors CY1 and CY2, differential mode inductors L1 and L2, differential mode capacitors CX1, CX2, and CX3, common mode inductors L3 and L4, and common mode capacitors CY3, CY4, CY5, and CY6. The positive output of the power supply characteristic protection circuit is connected to one end of feedthrough capacitor CY1, and the negative output is connected to one end of feedthrough capacitor CY2. Both feedthrough capacitors CY1 and CY2 are grounded. The other end of feedthrough capacitor CY1 is connected to the input of differential mode inductor L1, and feedthrough capacitor CY2 is connected to the input of differential mode inductor L2. The two ends of differential mode capacitor CX1 are connected to the outputs of differential mode inductors L1 and L2, respectively. The two ends of differential mode capacitor CX2 are also connected to the outputs of differential mode inductors L1 and L2, respectively. The output terminal of the differential mode inductor L2 is connected; the output terminal of the differential mode inductor L1 is connected to the positive terminal of the input terminal of the common mode inductor L3, and the output terminal of the differential mode inductor L2 is connected to the negative terminal of the input terminal of the common mode inductor L3. The two ends of the differential mode capacitor CX3 are connected to the two ends of the output terminal of the common mode inductor L3 respectively. The positive terminal of the output terminal of the common mode inductor L3 is connected to the first terminal of the common mode capacitor CY3, and the negative terminal of the output terminal of the common mode inductor L3 is connected to the first terminal of the common mode capacitor CY4. The second terminals of both the common mode capacitor CY3 and the common mode capacitor CY4 are connected to the chassis ground; the output terminal of the common mode inductor L3 is connected to the input terminal of the common mode inductor L4, the positive terminal of the output terminal of the common mode inductor L4 is connected to the first terminal of the common mode capacitor CY5, and the negative terminal of the output terminal of the common mode inductor L4 is connected to the first terminal of the common mode capacitor CY6. The second terminals of both the common mode capacitor CY5 and the common mode capacitor CY6 are connected to the chassis ground. The output terminal of the common mode capacitor CY5 is set as the power output terminal.

[0032] The LC filter circuit initially absorbs and discharges interference, improving the filtering efficiency of the system. The feedthrough capacitors CY1 and CY2 adopt an input-output compartment design to improve the high-frequency filtering capability of the filter device.

[0033] The above-mentioned design integrates conventional lightning protection filtering circuits, power supply characteristic protection circuits, and power supply filtering protection circuits into a single space. While meeting the filtering performance requirements against high-frequency external interference, it also provides protection against indirect and direct lightning strikes, thus satisfying the electromagnetic compatibility requirements of aircraft in complex electromagnetic environments. It can be widely used in the field of complex electromagnetic environments in aviation.

[0034] 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. A lightning protection filter circuit suitable for airborne windshield washer systems, characterized in that: It includes a lightning protection filter device, which is equipped with a lightning protection filter circuit. The lightning protection filter circuit includes a conventional lightning protection filter circuit, a power supply characteristic protection circuit, and a power supply filter protection circuit. The lightning protection conventional filter circuit, power supply characteristic protection circuit and power filter protection circuit are connected in sequence, and AC input terminal, signal output terminal and power output terminal are respectively arranged around the lightning protection filter device.

2. The lightning protection filter circuit for an airborne windshield washer system according to claim 1, characterized in that: The conventional lightning protection filter circuit includes transient suppression diodes D1, D2, and D3, wherein: The two ends of the transient suppression diode D1 are connected in parallel to the two ends of the AC input terminal. The two ends of the transient suppression diode D1 are respectively connected to the first end of the transient suppression diode D2 and the first end of the transient suppression diode D3. The second ends of the transient suppression diode D2 and the second ends of the transient suppression diode D3 are both connected to the chassis ground.

3. A lightning protection filter circuit for an airborne windshield washer system according to claim 2, characterized in that: The power supply characteristic protection circuit includes a Schottky diode D4, a voltage adjustment diode D5, a charging capacitor CX1, resistors R1, R2, R3, R4, R5, and R6, a PNP transistor Q1, and a MOSFET Q2, wherein: The anode of the Schottky diode D4 is connected to the positive output terminal of the conventional lightning protection filter circuit. The cathode of the Schottky diode D4 is split into two paths. One path of the cathode of the Schottky diode D4 is connected to the first terminal of resistor R1, and the other path of the cathode of the Schottky diode D4 is connected to the positive input terminal of the power supply filter protection circuit. The second terminal of resistor R1 is split into two paths. One path of the second terminal of resistor R1 is connected to the cathode of voltage adjustment diode D5, and the other path of the second terminal of resistor R1 is connected to resistor R2. The anode of voltage adjustment diode D5 is connected to the negative output terminal of the conventional lightning protection filter circuit. The positive terminal of the conventional lightning protection filter circuit is connected to the first terminal of resistor R5. The base of the PNP transistor Q1 is connected to the second terminal of resistor R5 and the first terminal of resistor R6. The second terminal of resistor R6 is connected to the collector of PNP transistor Q1. The collector of PNP transistor Q1 is connected to resistor R2 through resistor R3. The emitter of PNP transistor Q1 is connected to the second terminal of resistor R2. The second end of resistor R2 is connected to the gate of MOS transistor Q2, the source of MOS transistor Q2 is connected to the collector of PNP transistor Q, the source and drain of MOS transistor Q2 are respectively connected to the two ends of resistor R4, and the drain of MOS transistor Q2 is connected to the negative input terminal of the power supply filter protection circuit.

4. A lightning protection filter circuit for an airborne windshield washer system according to claim 3, characterized in that: The power supply filtering and protection circuit includes feedthrough capacitor CY1, feedthrough capacitor CY2, differential mode inductor L1, differential mode inductor L2, differential mode capacitor CX1, differential mode capacitor CX2, differential mode capacitor CX3, common mode inductor L3, common mode inductor L4, common mode capacitor CY3, common mode capacitor CY4, common mode capacitor CY5, and common mode capacitor CY6, wherein: The positive output terminal of the power supply characteristic protection circuit is connected to one end of the feedthrough capacitor CY1, and the negative output terminal of the power supply characteristic protection circuit is connected to one end of the feedthrough capacitor CY2. Both the feedthrough capacitors CY1 and CY2 are connected to the chassis ground. The other end of the feedthrough capacitor CY1 is connected to the input terminal of the differential mode inductor L1, and the feedthrough capacitor CY2 is connected to the input terminal of the differential mode inductor L2. The two ends of the differential mode capacitor CX1 are connected to the output terminals of the differential mode inductors L1 and L2, respectively. The two ends of the differential mode capacitor CX2 are also connected to the output terminals of the differential mode inductors L1 and L2, respectively. The output terminal of the differential mode inductor L1 is connected to the positive terminal of the input terminal of the common mode inductor L3, the output terminal of the differential mode inductor L2 is connected to the negative terminal of the input terminal of the common mode inductor L3, the two ends of the differential mode capacitor CX3 are respectively connected to the two ends of the output terminal of the common mode inductor L3, the positive terminal of the output terminal of the common mode inductor L3 is connected to the first terminal of the common mode capacitor CY3, the negative terminal of the output terminal of the common mode inductor L3 is connected to the first terminal of the common mode capacitor CY4, and the second terminals of the common mode capacitor CY3 and the second terminals of the common mode capacitor CY4 are both connected to the chassis ground. The output terminal of the common mode inductor L3 is connected to the input terminal of the common mode inductor L4. The positive terminal of the output terminal of the common mode inductor L4 is connected to the first terminal of the common mode capacitor CY5. The negative terminal of the output terminal of the common mode inductor L4 is connected to the first terminal of the common mode capacitor CY6. The second terminals of the common mode capacitors CY5 and CY6 are both connected to the chassis ground. The output terminal of the common mode capacitor CY5 is set as the power output terminal.

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