Strong electromagnetic pulse protection system for photoelectric pod

Abstract

The invention provides a photoelectric pod strong electromagnetic pulse protection system. The protection system comprises a port combination protection filter and a shafting combination protection filter. The port combination protection filter is used for filtering strong electromagnetic pulse interference entering from the port of the external connector in a coupling manner; the port combined protection filter comprises a first combined protection filter and a second combined protection filter; the shafting combined protection filter comprises a third combined protection filter and a fourth combined protection filter; the third combined protection filter comprises a power supply protection circuit, a differential signal protection circuit, an excitation signal protection circuit, a rotary transformer signal protection circuit and a motor signal protection circuit; the first, second and fourth combined protection filters comprise a power supply protection circuit and a differential signal protection circuit. Through targeted structural layout and circuit design, comprehensive and effective protection of strong electromagnetic pulse interference is realized, and stable and reliable operation of the photoelectric pod in a complex strong electromagnetic environment is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of strong electromagnetic protection technology, specifically a photoelectric pod strong electromagnetic pulse protection system. Background Technology

[0002] Optoelectronic pods, as core devices integrating optoelectronic detection, signal transmission, and servo control, are widely used in drones, aircraft, ships, and other carriers. Their operating environment is often filled with complex and diverse electromagnetic interference signals, mainly including radio electromagnetic waves, radar electromagnetic waves, and various communication signals. These traditional interference signals are characterized by low field strength and continuous wave characteristics. Therefore, early electromagnetic protection designs for optoelectronic pods mainly focused on filtering, structural shell shielding, and cable shielding. The design was primarily based on meeting the relevant assessment items in the People's Republic of China National Military Standard GJB151B "Electromagnetic Emission and Sensitivity Requirements for Military Equipment and Subsystems." Among these, CS114 (Power Line Conducted Sensitivity - Pulse), CS115 (Power Line Conducted Sensitivity - Spike Signal), CS116 (Power Line Conducted Sensitivity - Damped Oscillating Wave), and RS103 (Radiated Sensitivity - Electric Field) are core assessment indicators. These protective measures can effectively resist traditional low-field-strength continuous wave interference.

[0003] With the rapid development of modern electronic warfare technology, high-power microwave weapons and other strong radiation sources have gradually become an important part of complex electromagnetic environments. The strong electromagnetic pulses generated by these sources are characterized by high field strength, concentrated energy, and strong transient nature, and their interference intensity and destructive power far exceed those of traditional electromagnetic interference. However, the electromagnetic protection design of existing optoelectronic pods has not been specifically optimized for the characteristics of strong electromagnetic pulses, leading to numerous problems exposed in strong electromagnetic pulse irradiation environments. First, the external connector port lacks specific protection against strong electromagnetic pulses (ESPs). The external connector is a critical interface for power supply and signal transmission between the optoelectronic pod and external equipment, and it is also one of the main pathways for ESP interference to couple into the pod. Existing filtering designs can only handle low-intensity continuous wave interference; their protection capabilities are insufficient to withstand the instantaneous impact of strong ESPs, which can easily couple directly into the pod's wiring through this port.

[0004] Secondly, the azimuth and pitch axis systems have weak points in electromagnetic protection. As the core components for azimuth adjustment and pitch rotation of the optoelectronic pod, the axis system's rotating connections (such as slip rings) and structural gaps are difficult to completely shield electromagnetically, becoming another important pathway for strong electromagnetic pulse interference to enter the pod. Existing technology has not specifically strengthened the protection of these weak points, allowing interference signals to easily couple into the interior through the axis system.

[0005] Furthermore, the protection circuits are not sufficiently targeted. The azimuth axis system involves the transmission of special types of signals such as excitation signals, resolver signals, and motor signals. Existing protection circuits do not have corresponding protection modules designed for the transmission characteristics of these special signals, making these signal lines weak points for interference coupling and further reducing the overall protection effectiveness.

[0006] The aforementioned problems directly cause existing optoelectronic pods to malfunction in environments with strong electromagnetic pulse radiation, specifically manifesting as image interference and distortion, servo system malfunction, and communication link interruption. In severe cases, they can even cause damage to core components inside the pod, making it impossible for optoelectronic pods to be co-installed with high-power microwave payloads, which greatly limits their application scope and combat effectiveness in modern complex electromagnetic warfare scenarios. Summary of the Invention

[0007] To address the problem that existing optoelectronic pods lack targeted strong electromagnetic pulse (ESP) protection designs, resulting in their inability to function properly in strong EMP irradiation environments and their inability to be co-installed with high-power microwave payloads, this invention provides an EMP protection system for optoelectronic pods. Through targeted structural layout and circuit design, it achieves comprehensive and effective protection against EMP interference, ensuring the stable and reliable operation of the optoelectronic pod in complex strong electromagnetic environments.

[0008] To achieve the above objectives, the specific solution adopted by the present invention is as follows: A strong electromagnetic pulse protection system for an optoelectronic pod is installed on the optoelectronic pod. The optoelectronic pod includes an azimuth assembly and a pitch assembly. The azimuth assembly has an azimuth axis system, and the pitch assembly has a pitch axis system. The protection system includes a port combination protection filter and an axis combination protection filter. The port combination protection filter is used to filter out strong electromagnetic pulse interference coupled in from the external connector port; the port combination protection filter includes a first combination protection filter and a second combination protection filter, both of which include a power protection circuit and a differential signal protection circuit. The axis system combined protection filter includes a third combined protection filter and a fourth combined protection filter, which are used to filter out strong electromagnetic pulse interference coupled in from the azimuth axis system and the pitch axis system, respectively. The third combined protection filter includes a power supply protection circuit, a differential signal protection circuit, an excitation signal protection circuit, a resolver signal protection circuit, and a motor signal protection circuit. The fourth combined protection filter includes a power supply protection circuit and a differential signal protection circuit.

[0009] Furthermore, both the first combined protection filter and the second combined protection filter are located at the external connector port of the orientation assembly.

[0010] Furthermore, the orientation assembly is provided with a slip ring, and the third combined protection filter is disposed adjacent to the slip ring.

[0011] Furthermore, the fourth combined protection filter is located within the pitch assembly near the pitch axis.

[0012] Furthermore, the power supply protection circuit is used to protect the power supply, including bidirectional transient suppression diodes T1 and T2, X capacitors Cx1 and Cx2, Y capacitors Cy1, Cy2, Cy3 and Cy4, and common mode inductor L1; In this configuration, pin 1 of the bidirectional transient suppression diode T1 is connected to the positive terminal of the power input, and pin 2 is connected to ground. The first pin of the bidirectional transient suppression diode T2 is connected to the negative terminal of the power input, and the second pin is connected to ground. The common mode inductor L1 has its first pin connected to the positive input terminal of the power supply line, its second pin connected to the negative input terminal of the power supply line, its third pin connected to the negative output terminal of the power supply line, and its fourth pin connected to the positive output terminal of the power supply line. One end of the X capacitor Cx1 is connected to the positive terminal of the power input line, and the other end is connected to the negative terminal of the power input line. One end of the X capacitor Cx2 is connected to pin 4 of the common-mode inductor L1, and the other end is connected to pin 3 of the common-mode inductor L1. One end of the Y capacitor Cy1 is connected to the negative terminal of the power input line, and the other end is connected to ground; One end of the Y capacitor Cy2 is connected to the positive terminal of the power input line, and the other end is connected to ground; One end of the Y capacitor Cy3 is connected to pin 3 of the common mode inductor L1, and the other end is connected to ground; One end of the Y capacitor Cy4 is connected to pin 4 of the common-mode inductor L1, and the other end is connected to ground.

[0013] Furthermore, the differential signal protection circuit is used to protect the differential signal, including bidirectional transient suppression diodes T3 and T4, Y capacitors Cy5 and Cy6, and common mode inductor L2; In this configuration, pin 1 of the bidirectional transient suppression diode T3 is connected to the positive terminal of the differential signal line input, and pin 2 is connected to ground. The first pin of the bidirectional transient suppression diode T4 is connected to the negative terminal of the differential signal line input, and the second pin is connected to ground. The common-mode inductor L2 has its first pin connected to the positive input terminal of the differential signal line, its second pin connected to the negative input terminal of the differential signal line, its third pin connected to the negative output terminal of the differential signal line, and its fourth pin connected to the positive output terminal of the differential signal line. One end of the Y capacitor Cy5 is connected to pin 4 of the common mode inductor L2, and the other end is connected to ground; One end of the Y capacitor Cy6 is connected to pin 3 of the common-mode inductor L2, and the other end is connected to ground.

[0014] Furthermore, the excitation signal protection circuit is used to protect the excitation signal, including bidirectional transient suppression diodes T5 and T6, and a common-mode inductor L3; Among them, pin 1 of the bidirectional transient suppression diode T5 is connected to the J terminal of the excitation signal line, and pin 2 is connected to ground; The first pin of the bidirectional transient suppression diode T6 is connected to the K terminal of the excitation signal line, and the second pin is connected to ground. The common mode inductor L3 has its first pin connected to the J terminal of the excitation signal line, its second pin connected to the K terminal of the excitation signal line, its third pin connected to the K' terminal of the excitation signal line, and its fourth pin connected to the J' terminal of the excitation signal line.

[0015] Furthermore, the resolver signal protection circuit is used to protect the resolver signal, including bidirectional transient suppression diodes T7, T8, T9, T10, T11, T12, T13, T14, and T15, Y capacitors Cy7, Cy8, Cy9, Cy10, Cy11, Cy12, Cy13, Cy14, and Cy15, and a common-mode inductor L4; The common-mode inductor L4 is a nine-wire common-mode inductor. Its pins 1, 2, 3, 4, 5, 6, 7, 8, and 9 are connected to terminals A, B, C, D, E, F, G, H, and I of the resolver signal line, respectively, and its pins 18, 17, 16, 15, 14, 13, 12, 11, and 10 are connected to terminals A', B', C', D', E', F', G', H', and I' of the resolver signal line, respectively. The first pin of the bidirectional transient suppression diodes T7, T8, T9, T10, T11, T12, T13, T14, and T15 are respectively connected to terminals A, B, C, D, E, F, G, H, and I of the resolver signal line, and the second pin of each is connected to ground. Y capacitors Cy7, Cy8, Cy9, Cy10, Cy11, Cy12, Cy13, Cy14, and Cy15 are all three-terminal feedthrough capacitors. Their first terminals are connected to pins 18, 17, 16, 15, 14, 13, 12, 11, and 10 of the common-mode inductor L4, respectively. Their second terminals are connected to terminals A', B', C', D', E', F', G', H', and I' of the resolver signal line, respectively. Their third terminals are all connected to ground.

[0016] Furthermore, the motor signal protection circuit is used to protect the motor signal, including bidirectional transient suppression diodes T16 and T17, and a common-mode inductor L5; Among them, pin 1 of the bidirectional transient suppression diode T16 is connected to the motor signal line L, and pin 2 is connected to ground; The first pin of the bidirectional transient suppression diode T17 is connected to the motor signal line M, and the second pin is connected to ground. The common mode inductor L4 has its first pin connected to the motor signal line L, its second pin connected to the motor signal line M, its third pin connected to the motor signal line M', and its fourth pin connected to the motor signal line L'.

[0017] Beneficial effects: (1) This invention accurately locates the two core coupling paths (external connector port and azimuth / pitch axis) of strong electromagnetic pulse interference entering the optoelectronic pod. By setting up port combination protection filters and axis combination protection filters, it achieves full coverage of key weak parts, solves the problem of single protection path and blind spots in the existing technology, and blocks the entry channel of interference signals from the source.

[0018] (2) The external connector ports mainly use power and differential signals, so the first and second combined protection filters only integrate power protection circuits and differential signal protection circuits; the azimuth axis system involves a variety of special signals such as power, differential signals, excitation signals, resolver signals, and motor signals, so the third combined protection filter integrates five types of protection circuits; the pitch axis system mainly uses power and differential signals, so the fourth combined protection filter matches the corresponding protection circuit. This "configuration on demand" design ensures the protection effect, avoids redundant design, and does not affect the normal transmission of the original signals of the optoelectronic pod.

[0019] (3) Through the synergistic effect of the rapid clamping discharge of the bidirectional transient suppression diode, the efficient filtering of the capacitor, and the strong interference suppression of the common mode inductor, the protection system of the present invention can withstand the strong electromagnetic pulse radiation with a field strength of 300KV / m, which far exceeds the protection level of traditional protection technology and successfully solves the pain point that the existing optoelectronic pod cannot work normally in the strong electromagnetic pulse environment.

[0020] (4) The protection system of the present invention has been verified by flight test and can be installed on UAV with a certain type of high-power microwave equipment and work stably. It effectively solves the technical bottleneck that the existing optoelectronic pod cannot be installed with high-power microwave payload, and greatly expands the application scope of optoelectronic pod in complex scenarios such as modern electromagnetic confrontation and high-power microwave weapon cooperative combat.

[0021] (5) The structural layout of the protection system (such as the third combined protection filter being located near the slip ring and the fourth combined protection filter being located in the pitch assembly near the pitch axis) fully considers the mechanical structure and working characteristics of the optoelectronic pod. The circuit design conforms to the basic principles of electromagnetic protection and has been verified by actual testing. It can work stably in strong electromagnetic pulse environments and flight conditions, and will not have a negative impact on the original functions of the optoelectronic pod such as servo control, image transmission, and communication. It has extremely high reliability. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a power supply protection circuit.

[0023] Figure 2 This is the schematic diagram of a differential signal circuit.

[0024] Figure 3 This is a schematic diagram of the excitation signal protection circuit.

[0025] Figure 4 This is a schematic diagram of a resolver signal protection circuit.

[0026] Figure 5 This is a schematic diagram of a motor signal protection circuit.

[0027] Figure 6 This is a schematic diagram of the layout of the protective filter on the optoelectronic pod.

[0028] Figure 6 In the diagram, N represents the first combined protection filter, Q represents the second combined protection filter, S represents the third combined protection filter, and T represents the fourth combined protection filter. Detailed Implementation

[0029] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0030] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0031] like Figure 6As shown, the electro-optical pod's strong electromagnetic pulse protection system of this invention constructs a comprehensive protection system through a dual layout of "port protection + axis system protection." Specifically, the port combination protection filters (first combination protection filter N and second combination protection filter Q) are located at the external connector port of the azimuth assembly, focusing on intercepting strong electromagnetic pulse interference coupled in through this port. In the axis system combination protection filters, the third combination protection filter S is located near the slip ring within the azimuth assembly, specifically protecting weak points in the azimuth axis system, while the fourth combination protection filter T is located within the pitch assembly near the pitch axis system, focusing on intercepting interference from the pitch axis system. These four combination protection filters cover key interference coupling paths, forming a comprehensive protection network that ensures strong electromagnetic pulse interference cannot enter the electro-optical pod through any weak points. The following section provides a detailed description of each combination protection filter and its included protection circuitry.

[0032] I. Combined Protection Filter The first combined protection filter N includes a power supply protection circuit and a differential signal protection circuit, and is installed at the external connector port of the optoelectronic pod's azimuth assembly (i.e., near the azimuth assembly's input port). Its core function is to initially intercept strong electromagnetic pulse interference coupled in through the external connector port. Through internal circuitry, it clamps the pulse voltage in the power supply and differential signal lines to a safe level, while simultaneously discharging and attenuating coupled interference signals, reducing electromagnetic interference to below the sensitivity level of the optoelectronic pod's internal circuitry, thus providing the first line of defense for the internal circuitry.

[0033] The second combined protection filter Q has the same structure as the first combined protection filter N (both include power protection circuits and differential signal protection circuits) and is also installed at the external connector port of the optoelectronic pod orientation assembly. Its core function is to form a synergistic protection with the first combined protection filter N, accurately intercepting strong electromagnetic pulse interference coupled into the external connector port. Through targeted clamping of the pulse voltage of the power supply line and differential signal line by internal circuitry, it efficiently discharges and attenuates interference signals. Complementing the first combined protection filter N, it forms a comprehensive port protection without blind spots, ensuring that electromagnetic interference is reduced to the tolerance range of the internal circuitry, jointly building a solid first line of defense.

[0034] Specifically, the first combined protection filter N is suitable for a 28VDC / 8A power supply circuit. The second combined protection filter Q is suitable for a 12VDC / 5A circuit. Both support simplex / duplex 422.

[0035] The third combined protection filter S includes a power supply protection circuit, a differential signal protection circuit, an excitation signal protection circuit, a resolver signal protection circuit, and a motor signal protection circuit, and is installed near the slip ring inside the azimuth assembly (adjacent to the slip ring). Since the slip ring connection of the azimuth axis system is a weak point in electromagnetic protection, strong electromagnetic pulses can easily couple into the azimuth assembly through this point. Furthermore, the azimuth axis system involves various special signal transmissions. This filter is specifically designed to provide comprehensive protection for all types of signal lines related to the azimuth axis system. Through the synergistic effect of multiple types of protection circuits, it comprehensively suppresses strong electromagnetic pulse interference coupled from the azimuth axis system, protecting circuit components related to the azimuth axis system (such as motors, rotary encoders, etc.) from interference or damage.

[0036] The fourth combined protection filter T includes a power supply protection circuit and a differential signal protection circuit, and is installed inside the optoelectronic pod's pitch assembly near the pitch axis. Structural gaps and rotating connections in the pitch axis can easily become interference coupling channels. This filter provides specific protection for the pitch axis's power supply lines and differential signal lines. Through clamping, discharging, and attenuation, it effectively suppresses strong electromagnetic pulse interference coupled from the pitch axis, ensuring the normal operation of servo control, signal transmission, and other functions related to the pitch axis.

[0037] II. Various protection circuits Next, each protection circuit will be described in detail with reference to the attached diagram.

[0038] (1) Power supply protection circuit The power protection circuit is the core circuit that ensures the safety of the power supply to the optoelectronic pod. It is used to resist the impact of strong electromagnetic pulses on the internal electrical components through the power supply line. The following is a combination of... Figure 1 The connection relationships between its various components are explained in detail.

[0039] Bidirectional transient voltage suppressor diode T1: Pin 1 is connected to the positive terminal of the power input, and pin 2 is connected to ground. This bidirectional transient voltage suppressor diode has a nanosecond-level response speed. When a transient overvoltage occurs at the positive terminal of the power input due to a strong electromagnetic pulse, T1 will quickly break down and conduct, clamping the overvoltage within its rated safe voltage range. Simultaneously, excess pulse energy is rapidly discharged to ground through pin 2, preventing the overvoltage from entering subsequent power supply circuits and protecting internal components from damage.

[0040] Bidirectional transient voltage suppressor diode T2: Pin 1 is connected to the negative terminal of the power input, and pin 2 is connected to ground. Its function complements that of T1, specifically protecting against transient overvoltages at the negative terminal of the power input. When an overvoltage caused by a strong electromagnetic pulse occurs at the negative input terminal, T2 quickly conducts, clamping the overvoltage and dissipating the pulse energy, ensuring that neither the positive nor negative terminals of the power input will experience overvoltages that could endanger subsequent circuits.

[0041] Common-mode inductor L1: Pin 1 connects to the positive input terminal of the power supply line, pin 2 connects to the negative input terminal, pin 3 connects to the negative output terminal, and pin 4 connects to the positive output terminal. The common-mode inductor has two windings with the same direction and number of turns, connected in series in the positive and negative lines of the power supply line, respectively. When common-mode interference signals (i.e., interference signals existing simultaneously on both power lines relative to ground) appear in the power supply line, the magnetic fields generated by the two windings are in the same direction. The mutual inductance makes the common-mode inductor present a large impedance to the common-mode interference signal, effectively suppressing the transmission of the common-mode interference signal to subsequent circuits. For normal differential-mode current (operating current), the magnetic fields generated by the two windings are in opposite directions and cancel each other out. The common-mode inductor presents a low impedance and does not affect the transmission of normal power supply current. Its special pin connection method further optimizes the suppression effect of common-mode interference.

[0042] X capacitor Cx1: One end is connected to the positive terminal of the power input, and the other end is connected to the negative terminal of the power input. The X capacitor is a device specifically designed to filter differential-mode interference, which is an interference signal existing between the positive and negative terminals of the power supply line. Cx1 utilizes its capacitive reactance to attenuate the differential-mode interference signal at the power input terminal, consuming the energy of the differential-mode interference and reducing its impact on subsequent power supply circuits.

[0043] Capacitor Cx2 (X): One end is connected to pin 4 of common-mode inductor L1 (positive power output terminal), and the other end is connected to pin 3 of common-mode inductor L1 (negative power output terminal). Its function is to perform secondary filtering on the differential-mode interference after it has been suppressed by the common-mode inductor, further attenuating the differential-mode interference signal at the power line output terminal, ensuring that differential-mode interference in the power supply current provided to the internal circuit is fully filtered out, and guaranteeing power supply stability.

[0044] Y-capacitor Cy1: One end is connected to the negative input terminal of the power supply line, and the other end is connected to ground. The Y-capacitor is mainly used to filter common-mode interference, specifically targeting the common-mode interference signal between the negative input terminal of the power supply line and ground. Through its capacitive reactance characteristics, it dissipates the common-mode interference energy at the negative input terminal to ground, preventing common-mode interference from propagating in the power supply line.

[0045] Y-capacitor Cy2: One end is connected to the positive input terminal of the power line, and the other end is connected to ground. Used in conjunction with Cy1, it is specifically designed to filter out common-mode interference signals between the positive input terminal of the power line and ground, dissipating the common-mode interference energy at the positive input terminal to ground, thus providing initial protection against common-mode interference at both the positive and negative input terminals of the power line relative to ground.

[0046] Y-capacitor Cy3: One end is connected to pin 3 of common-mode inductor L1 (the negative terminal of the power supply output), and the other end is connected to ground. It is used to filter out common-mode interference signals between the negative terminal of the power supply output and ground, and to perform secondary discharge on the common-mode interference after it has been suppressed by the common-mode inductor, further reducing the transmission of common-mode interference to the internal circuit.

[0047] Y capacitor Cy4: One end is connected to pin 4 of common-mode inductor L1 (positive output terminal of the power line), and the other end is connected to ground. Working together with Cy3, it filters out common-mode interference signals between the positive output terminal of the power line and ground, dissipating the common-mode interference energy of the positive output terminal to ground, ensuring that common-mode interference in the power line is fully suppressed, and providing a clean and stable power supply for the internal circuitry.

[0048] (2) Differential signal protection circuit Differential signal protection circuits are used to protect differential signal lines (such as communication signal transmission lines) in optoelectronic pods from signal transmission interruption caused by strong electromagnetic pulse interference. The following section combines... Figure 2 The connection relationships between its various components are explained in detail.

[0049] Bidirectional transient voltage suppressor diode T3: Pin 1 is connected to the positive terminal of the differential signal line input, and pin 2 is connected to ground. When the positive terminal of the differential signal line input is irradiated by a strong electromagnetic pulse, generating a transient overvoltage, T3 quickly breaks down and conducts, clamping the overvoltage within a safe range. At the same time, it discharges excess pulse energy to ground, preventing the overvoltage from damaging differential signal transmission devices (such as transmission chips, interface devices, etc.) or affecting the normal operation of subsequent signal processing circuits.

[0050] Bidirectional transient voltage suppressor diode T4: Pin 1 is connected to the negative terminal of the differential signal line input, and pin 2 is connected to ground. It complements T3 in protection, clamping and dissipating energy from transient overvoltages at the negative terminal of the differential signal line input, ensuring that neither the positive nor negative terminals of the differential signal line input experience overvoltage surges due to strong electromagnetic pulses, thus guaranteeing the balanced transmission characteristics of the differential signal.

[0051] Common-mode inductor L2: Pin 1 connects to the positive input terminal of the differential signal line, pin 2 connects to the negative input terminal of the differential signal line, pin 3 connects to the negative output terminal of the differential signal line, and pin 4 connects to the positive output terminal of the differential signal line. Its core function is to suppress common-mode interference in differential signal lines. Common-mode interference can disrupt the balance characteristics of differential signals, leading to signal distortion. Through the mutual inductance of its windings, L2 generates a large impedance to common-mode interference signals, effectively suppressing their transmission. Conversely, it presents a low impedance to normal differential signals (differential-mode signals), ensuring normal transmission quality.

[0052] Y-capacitor Cy5: One end is connected to pin 4 of common-mode inductor L2 (positive output of differential signal line), and the other end is connected to ground. It is used to filter out common-mode interference signals between the positive output of differential signal line and ground, dissipating common-mode interference energy to ground, and further suppressing the impact of common-mode interference on subsequent signal processing circuits.

[0053] Y-capacitor Cy6: One end is connected to pin 3 of common-mode inductor L2 (the negative output terminal of the differential signal line), and the other end is connected to ground. Together with Cy5, it filters out common-mode interference signals between the negative output terminal of the differential signal line and ground, dissipating common-mode interference energy to ground. Working in conjunction with T3, T4, and L2, it forms comprehensive protection for the differential signal line, ensuring stable and accurate transmission of the differential signal.

[0054] (3) Excitation signal protection circuit Excitation signal protection circuit is used to protect the excitation signal lines related to the azimuth axis system. The excitation signal is a key signal to ensure the normal operation of the azimuth axis system drive components. The following section will discuss this in conjunction with... Figure 3 The connection relationships between its various components are explained in detail.

[0055] Bidirectional transient suppression diode T5: Pin 1 is connected to the J terminal of the excitation signal line, and pin 2 is connected to ground. When an overvoltage caused by a strong electromagnetic pulse occurs at the J terminal of the excitation signal line, T5 quickly breaks down and conducts, clamping the overvoltage to a safe level. At the same time, it discharges the pulse energy to ground, preventing the overvoltage from damaging the excitation signal transmission device or affecting the normal output of the excitation signal, and ensuring the stable excitation power supply of the azimuth axis drive components.

[0056] Bidirectional transient voltage suppressor diode T6: Pin 1 is connected to the K terminal of the excitation signal line, and pin 2 is connected to ground. In conjunction with T5, it protects against overvoltage at the K terminal of the excitation signal line, achieving overvoltage clamping and energy dissipation, ensuring that the voltage at the J and K terminals of the excitation signal line remains stable within a safe range, and preventing distortion of the excitation signal due to overvoltage.

[0057] Common-mode inductor L3: Pin 1 connects to the J terminal of the excitation signal line, pin 2 connects to the K terminal of the excitation signal line, pin 3 connects to the K' terminal of the excitation signal line, and pin 4 connects to the J' terminal of the excitation signal line. It is used to suppress common-mode interference in the excitation signal line. Common-mode interference can cause excitation signal distortion, affecting the working accuracy of the azimuth axis drive components. L3, through the mutual inductance characteristics of its windings, generates a large impedance to common-mode interference signals, suppressing common-mode interference transmission without affecting the transmission of normal excitation signals, ensuring that the excitation signal can be accurately and stably transmitted to the target component.

[0058] (4) Resolver signal protection circuit The resolver signal protection circuit is used to protect the resolver signal lines of the azimuth axis system. The resolver signal (output signal of the rotary encoder) is the core signal for detecting the rotation angle and speed of the azimuth axis system, and its transmission quality directly affects the servo control accuracy of the photoelectric pod. The following section will discuss this in conjunction with... Figure 4 The connection relationships between its various components are explained in detail.

[0059] Common-mode inductor L4: This is a nine-wire common-mode inductor. Pins 1-9 are connected to the AI ​​terminals of the resolver signal lines, and pins 18-10 are connected to the A'-I' terminals of the resolver signal lines. The resolver signal lines contain multiple synchronization signals. The nine-wire common-mode inductor can simultaneously suppress common-mode interference from multiple resolver signals. Each winding corresponds to one resolver signal. Through mutual inductance, it generates a large impedance to common-mode interference in each signal, suppressing common-mode interference transmission, ensuring balanced transmission of multiple resolver signals, avoiding signal distortion caused by common-mode interference, and ensuring the accuracy of the resolver signal in detecting the rotational parameters of the azimuth axis system.

[0060] Bidirectional transient voltage suppressor diodes T7-T15: There are 9 in total. Pin 1 is connected to the AI ​​terminal of each resolver signal line, and pin 2 is connected to ground. Each diode corresponds to the input terminal of one resolver signal. When an overvoltage occurs on a resolver signal line due to a strong electromagnetic pulse, the corresponding diode quickly breaks down and conducts, clamping the overvoltage to a safe level and dissipating the pulse energy to ground. This achieves precise protection for the input terminal of each resolver signal, preventing overvoltage from damaging the resolver signal transmission device or affecting the signal detection circuit.

[0061] Y-capacitors Cy7-Cy15: There are nine in total, all three-terminal feedthrough capacitors. The first terminal is connected to pins 18-10 of the common-mode inductor L4, the second terminal is connected to the A'-I' terminals of the resolver signal line, and the third terminal is connected to ground. These three-terminal feedthrough capacitors offer excellent filtering performance and shielding, effectively filtering out common-mode interference signals between the resolver signal line output and ground. Each capacitor corresponds to the output of one resolver signal, discharging the common-mode interference energy in each signal to ground through the third terminal, further suppressing the impact of common-mode interference on subsequent resolver signal processing circuits, and ensuring the stability and detection accuracy of the resolver signal transmission.

[0062] (5) Motor signal protection circuit The motor signal protection circuit is used to protect the motor signal lines of the azimuth axis system. The motor signal is a critical signal controlling the operation of the azimuth axis system motor; its stability directly affects the motor's operating accuracy and the rotational performance of the azimuth axis system. The following section combines... Figure 5 The connection relationships between its various components are explained in detail.

[0063] Bidirectional transient voltage suppressor diode T16: Pin 1 is connected to the L terminal of the motor signal line, and pin 2 is connected to ground. When the L terminal of the motor signal line is subjected to a strong electromagnetic pulse and an overvoltage is generated, T16 quickly breaks down and conducts, clamping the overvoltage within a safe range, while simultaneously dissipating the pulse energy to ground, preventing the overvoltage from damaging motor signal control devices (such as motor driver chips) or affecting the normal operation of the motor.

[0064] Bidirectional transient voltage suppressor diode T17: Pin 1 is connected to the motor signal line M terminal, and pin 2 is connected to ground. In conjunction with T16, it clamps and discharges overvoltage at the motor signal line M terminal, ensuring stable voltage at the L and M terminals of the motor signal line and preventing distortion of the motor control signal due to overvoltage.

[0065] Common-mode inductor L5: Pin 1 connects to the L terminal of the motor signal line, pin 2 connects to the M terminal of the motor signal line, pin 3 connects to the M' terminal of the motor signal line, and pin 4 connects to the L' terminal of the motor signal line. It is used to suppress common-mode interference in the motor signal line. Common-mode interference can cause distortion of the motor control signal, affecting the speed and direction control accuracy of the motor. L5, through the mutual inductance characteristics of its windings, generates a large impedance to common-mode interference signals, suppressing the transmission of common-mode interference without affecting the transmission of normal motor control signals. This ensures that the motor can accurately receive control signals and guarantees the stable rotation of the orientation axis system.

[0066] The photoelectric pod's strong electromagnetic pulse protection system of this invention has undergone specialized testing and practical application verification: In a strong electromagnetic pulse irradiation test with a field strength of 300KV / m, the photoelectric pod was able to operate normally without any problems such as image interference, servo malfunction, or communication interruption; In a flight test with a certain type of high-power microwave equipment installed on a UAV, all functions of the photoelectric pod remained normal, fully demonstrating the protective effect and reliability of the system, and successfully solving the technical problems that existing photoelectric pods cannot resist strong electromagnetic pulse interference and cannot be co-installed with high-power microwave loads.

[0067] In summary, this invention clamps the pulse voltage entering the optoelectronic pod by using a port combination filter and a shaft system combination protection filter, attenuates and discharges interference signals coupled into the circuit, and reduces electromagnetic interference signals to below the equipment's sensitivity level, thereby achieving the effect of protecting against strong electromagnetic pulse interference.

[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the invention in any way. All equivalent transformations or modifications made in accordance with the essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A strong electromagnetic pulse protection system for an optoelectronic pod, mounted on an optoelectronic pod, the optoelectronic pod including an azimuth assembly and a pitch assembly, the azimuth assembly having an azimuth axis system and the pitch assembly having a pitch axis system, the protection system including a port combination protection filter and an axis combination protection filter; in, The port combination protection filter is used to filter out strong electromagnetic pulse interference coupled in from the external connector port; the port combination protection filter includes a first combination protection filter and a second combination protection filter, both of which include a power protection circuit and a differential signal protection circuit. The axis system combined protection filter includes a third combined protection filter and a fourth combined protection filter, which are used to filter out strong electromagnetic pulse interference coupled in from the azimuth axis system and the pitch axis system, respectively. The third combined protection filter includes a power supply protection circuit, a differential signal protection circuit, an excitation signal protection circuit, a resolver signal protection circuit, and a motor signal protection circuit. The fourth combined protection filter includes a power supply protection circuit and a differential signal protection circuit.

2. The photoelectric pod strong electromagnetic pulse protection system according to claim 1, characterized in that, Both the first combined protection filter and the second combined protection filter are located at the external connector port of the orientation assembly.

3. The photoelectric pod strong electromagnetic pulse protection system according to claim 1, characterized in that, The orientation assembly is provided with a slip ring, and the third combined protection filter is disposed adjacent to the slip ring.

4. The photoelectric pod strong electromagnetic pulse protection system according to claim 1, characterized in that, The fourth combined protection filter is located within the pitch assembly near the pitch axis.

5. The photoelectric pod strong electromagnetic pulse protection system according to claim 1, characterized in that, The power protection circuit is used to protect the power supply, including bidirectional transient suppression diodes T1 and T2, X capacitors Cx1 and Cx2, Y capacitors Cy1, Cy2, Cy3 and Cy4, and common mode inductor L1; In this configuration, pin 1 of the bidirectional transient suppression diode T1 is connected to the positive terminal of the power input, and pin 2 is connected to ground. The first pin of the bidirectional transient suppression diode T2 is connected to the negative terminal of the power input, and the second pin is connected to ground. The common mode inductor L1 has its first pin connected to the positive input terminal of the power supply line, its second pin connected to the negative input terminal of the power supply line, its third pin connected to the negative output terminal of the power supply line, and its fourth pin connected to the positive output terminal of the power supply line. One end of the X capacitor Cx1 is connected to the positive terminal of the power input line, and the other end is connected to the negative terminal of the power input line. One end of the X capacitor Cx2 is connected to pin 4 of the common-mode inductor L1, and the other end is connected to pin 3 of the common-mode inductor L1. One end of the Y capacitor Cy1 is connected to the negative terminal of the power input line, and the other end is connected to ground; One end of the Y capacitor Cy2 is connected to the positive terminal of the power input line, and the other end is connected to ground; One end of the Y capacitor Cy3 is connected to pin 3 of the common mode inductor L1, and the other end is connected to ground; One end of the Y capacitor Cy4 is connected to pin 4 of the common-mode inductor L1, and the other end is connected to ground.

6. The photoelectric pod strong electromagnetic pulse protection system according to claim 1, characterized in that, The differential signal protection circuit is used to protect differential signals, including bidirectional transient suppression diodes T3 and T4, Y capacitors Cy5 and Cy6, and common mode inductor L2; In this configuration, pin 1 of the bidirectional transient suppression diode T3 is connected to the positive terminal of the differential signal line input, and pin 2 is connected to ground. The first pin of the bidirectional transient suppression diode T4 is connected to the negative terminal of the differential signal line input, and the second pin is connected to ground. The common-mode inductor L2 has its first pin connected to the positive input terminal of the differential signal line, its second pin connected to the negative input terminal of the differential signal line, its third pin connected to the negative output terminal of the differential signal line, and its fourth pin connected to the positive output terminal of the differential signal line. One end of the Y capacitor Cy5 is connected to pin 4 of the common mode inductor L2, and the other end is connected to ground; One end of the Y capacitor Cy6 is connected to pin 3 of the common-mode inductor L2, and the other end is connected to ground.

7. The photoelectric pod strong electromagnetic pulse protection system according to claim 1, characterized in that, The excitation signal protection circuit is used to protect the excitation signal, including bidirectional transient suppression diodes T5 and T6, and common mode inductor L3; Among them, pin 1 of the bidirectional transient suppression diode T5 is connected to the J terminal of the excitation signal line, and pin 2 is connected to ground; The first pin of the bidirectional transient suppression diode T6 is connected to the K terminal of the excitation signal line, and the second pin is connected to ground. The common mode inductor L3 has its first pin connected to the J terminal of the excitation signal line, its second pin connected to the K terminal of the excitation signal line, its third pin connected to the K' terminal of the excitation signal line, and its fourth pin connected to the J' terminal of the excitation signal line.

8. The photoelectric pod strong electromagnetic pulse protection system according to claim 1, characterized in that, The resolver signal protection circuit is used to protect the resolver signal, including bidirectional transient suppression diodes T7, T8, T9, T10, T11, T12, T13, T14, and T15, Y capacitors Cy7, Cy8, Cy9, Cy10, Cy11, Cy12, Cy13, Cy14, and Cy15, and a common-mode inductor L4; The common-mode inductor L4 is a nine-wire common-mode inductor. Its pins 1, 2, 3, 4, 5, 6, 7, 8, and 9 are connected to terminals A, B, C, D, E, F, G, H, and I of the resolver signal line, respectively, and its pins 18, 17, 16, 15, 14, 13, 12, 11, and 10 are connected to terminals A', B', C', D', E', F', G', H', and I' of the resolver signal line, respectively. The first pin of the bidirectional transient suppression diodes T7, T8, T9, T10, T11, T12, T13, T14, and T15 are respectively connected to terminals A, B, C, D, E, F, G, H, and I of the resolver signal line, and the second pin of each is connected to ground. Y capacitors Cy7, Cy8, Cy9, Cy10, Cy11, Cy12, Cy13, Cy14, and Cy15 are all three-terminal feedthrough capacitors. Their first terminals are connected to pins 18, 17, 16, 15, 14, 13, 12, 11, and 10 of the common-mode inductor L4, respectively. Their second terminals are connected to terminals A', B', C', D', E', F', G', H', and I' of the resolver signal line, respectively. Their third terminals are all connected to ground.

9. The photoelectric pod strong electromagnetic pulse protection system according to claim 1, characterized in that, The motor signal protection circuit is used to protect motor signals, including bidirectional transient suppression diodes T16 and T17, and common mode inductor L5; Among them, pin 1 of the bidirectional transient suppression diode T16 is connected to the motor signal line L, and pin 2 is connected to ground; The first pin of the bidirectional transient suppression diode T17 is connected to the motor signal line M, and the second pin is connected to ground. The common mode inductor L4 has its first pin connected to the motor signal line L, its second pin connected to the motor signal line M, its third pin connected to the motor signal line M', and its fourth pin connected to the motor signal line L'.

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