An integrated lightning protection filter assembly for a marine fan inverter

Abstract

The application discloses an integrated lightning protection filter assembly for a ship fan frequency converter, and relates to the technical field of ship fan protection.The integrated lightning protection filter assembly comprises a metal cavity, a lightning protection circuit and a filter circuit; the lightning protection circuit and the filter circuit are cascaded; the inside of the metal cavity is divided into a first compartment for accommodating the lightning protection circuit and a second compartment for accommodating the filter circuit, and the first compartment and the second compartment form an electromagnetic shielding isolation structure; the lightning protection circuit comprises at least one temperature fuse voltage-dependent resistor and is configured to clamp line-line surges and line-ground surges of an input alternating current power supply; the filter circuit comprises a second-order LC filter network provided with a cutoff frequency, and the second-order LC filter network comprises a differential-mode inductor, a common-mode inductor, a differential-mode capacitor and a common-mode capacitor; the differential-mode capacitor and the common-mode capacitor are connected in parallel at the output end of the common-mode inductor.The application provides a lightning protection filter device which improves lightning surge suppression effect and enhances electromagnetic compatibility.

Description

Technical Field

[0001] This application relates to the field of ship wind turbine protection technology, and in particular to an integrated lightning protection filter component for ship wind turbine frequency converters. Background Technology

[0002] Shipboard electrical systems are the core of ensuring shipboard combat operations, navigation, and crew life; their stability directly affects the ship's survivability and mission execution capabilities. According to GJB 4000-2000 "General Specifications for Ships, Group 3: Electrical Systems," shipboard electrical systems must withstand complex electromagnetic environments and extreme operating conditions, among which lightning surges are one of the main factors threatening system safety.

[0003] When lightning strikes a ship or nearby area, it generates transient overvoltages and overcurrents with high amplitude (up to several kilovolts), short duration (microseconds), but enormous energy. This surge energy can break down equipment insulation, burn out sensitive circuit components, and even paralyze the main power distribution system. The GJB 4000-2000 standard explicitly requires that AC 380V power systems must withstand voltage spikes of 2500Vac (internal resistance 2Ω) between lines and 2500Vac (internal resistance 12Ω) between lines and ground.

[0004] In addition, lightning protection for shipboard power systems must also take into account electromagnetic compatibility (GJB 151A-97 or GJB 151B-2013), insulation protection, and grounding requirements to ensure that core loads can still be powered after surge impacts. This places stringent requirements on the response speed, clamping capability, and current-carrying capacity of lightning protection circuits.

[0005] Currently, only a single-stage varistor (or a gas discharge tube) is installed at the power input, resulting in a high clamping residual voltage for 2500VAC surges, and this residual voltage lasts for a long time. This residual energy is transferred to the downstream frequency converter, causing abnormal output of the sampling transformer, which in turn triggers the DSP to issue a false shutdown command, causing unexpected equipment shutdown and resulting in poor protection. Furthermore, commercially available general-purpose filters or separately installed surge protection-filter components lack effective electromagnetic shielding designs. The transient strong electromagnetic field generated when the surge protection circuit operates can easily couple with the filter circuit or internal signal lines, leading to a deterioration of the internal electromagnetic environment. This makes it difficult to meet the conducted and radiated emission requirements of GJB 151B-2013, resulting in poor electromagnetic compatibility.

[0006] Therefore, it is of great research value and significance to provide a lightning protection filter device that can both improve the suppression effect of lightning surges and enhance electromagnetic compatibility. Summary of the Invention

[0007] In order to provide a lightning protection filter device that can improve both lightning surge suppression and electromagnetic compatibility, this application provides an integrated lightning protection filter component for ship wind turbine frequency converters.

[0008] Firstly, the objective of this invention is achieved through the following technical solution: An integrated lightning protection and filtering component for a shipboard wind turbine frequency converter includes: a metal cavity, a lightning protection circuit, and a filtering circuit; the lightning protection circuit and the filtering circuit are cascaded. The interior of the metal cavity is divided into a first compartment for accommodating lightning protection circuits and a second compartment for accommodating filtering circuits, the first compartment and the second compartment forming an electromagnetic shielding isolation structure; The surge protection circuit includes at least one temperature-sensitive fuse varistor configured to clamp line-to-line surges and line-to-ground surges of the input AC power supply; The filtering circuit includes a second-order LC filter network with a cutoff frequency. The second-order LC filter network includes a differential-mode inductor, a common-mode inductor, a differential-mode capacitor, and a common-mode capacitor. The differential-mode inductor and the common-mode inductor are connected in series. The differential-mode capacitor and the common-mode capacitor are connected in parallel at the output terminal of the common-mode inductor.

[0009] By adopting the above technical solution, the compartmentalized design of the metal cavity can effectively isolate high-frequency interference such as switching noise and thunder pulses, significantly reducing internal electromagnetic coupling and radiated emissions, and achieving a high-reliability electromagnetic shielding effect. This application achieves multi-stage clamping and absorption of 2500V surge voltage through the coordinated operation of the temperature fuse varistor (TFMOV) in the surge protection circuit and the LC network of the filter circuit. Specifically, for line-to-line surges (2500V, internal resistance 2Ω): the TFMOV clamps the voltage to 1120V, and then the LC filter network suppresses it to below 700V, avoiding malfunction of the downstream sampling circuit; for line-to-ground surges (2500V, internal resistance 12Ω): the TFMOV clamps the voltage to 550V, and the filter circuit further suppresses the residual voltage, ensuring that the insulation resistance is maintained above 100MΩ@1000Vdc. To achieve high-frequency interference suppression and energy efficiency optimization, a second-order LC filter network (with a cutoff frequency of 10kHz) utilizes a coordinated design of differential-mode and common-mode paths to achieve 40dB insertion loss at a 100kHz switching frequency, significantly suppressing pulse interference caused by du / dt and di / dt. Simultaneously, the capacitance values ​​strictly adhere to the GJB151B standard (e.g., capacitance <0.1μF for 50Hz devices), avoiding energy loss due to excessive capacitive load.

[0010] Specifically, when a 2500VAC line-to-line or line-to-ground surge is injected, the temperature-sensitive fuse varistor (TFMOV) in the surge protection circuit responds immediately, rapidly reducing its impedance from megaohms to a few ohms. This instantly clamps the surge voltage, which can reach up to 2500V, to approximately 1120V (line-to-line) or 550V (line-to-ground), cutting off most of the energy from entering subsequent circuits, thus achieving the first stage of rapid surge clamping. The residual surge voltage (still a pulse signal) after initial clamping by the varistor enters the filter circuit. At this point, the second-order LC filter network not only acts on the fundamental frequency interference of the switching power supply, but its inductance and capacitance also significantly suppress the high-frequency components of the surge pulse. This avoids abnormal sampling of the current transformer due to "excessive residual voltage duration," thereby completely eliminating the problem of the main processor (DSP) erroneously triggering the PWM shutdown command. Therefore, this application provides a lightning protection filter device that can improve the lightning surge suppression effect and enhance electromagnetic compatibility. The product has high reliability and ensures the stable operation of ship wind turbine frequency converters in harsh electromagnetic environments.

[0011] In a preferred embodiment of this application: the surge protection circuit includes a first varistor group, a second varistor group, an inter-line capacitor group, and a line-to-ground capacitor group. The first varistor group and the inter-line capacitor group are connected in parallel to form a line-to-line surge suppression branch; the second varistor group and the line-to-ground capacitor group are connected in parallel to form a line-to-ground surge suppression branch; the operating voltage range of the first varistor group is 400VAC to 680VAC, and the operating voltage range of the second varistor group is 200VAC to 300VAC; the inter-line capacitor group and the line-to-ground capacitor group are connected between phase lines L1, L2, and L3.

[0012] By adopting the above technical solution, the lightning protection circuit is a dual-path surge suppression scheme composed of a first varistor group, a second varistor group, an inter-line capacitor group, and a line-to-ground capacitor group. The first varistor group provides a rapid response to differential mode lightning surges occurring between phases (L1-L2, L2-L3, L3-L1), with its operating voltage set within the range of 400VAC to 680VAC. This effectively addresses fluctuations in the ship's power grid (typically 380VAC ± 10%) while preventing false triggering under normal operating voltage peaks. The second varistor group is specifically designed to suppress common-mode surges between phase lines and ground, and its lower operating voltage (200VAC to 300VAC) ensures effective protection of weak points in the ground insulation. The introduction of the inter-line and line-to-ground capacitor groups enhances the bypass capability of high-frequency surge energy, especially under microsecond-level pulse effects, accelerating the energy dissipation process.

[0013] In a preferred embodiment, this application further includes: a differential-mode inductor group consisting of a plurality of the differential-mode inductors, a differential-mode capacitor group consisting of two common-mode inductors and a plurality of the differential-mode capacitors; the plurality of differential-mode inductor groups are respectively connected in series in the input path of the phase lines of the three-phase AC power supply; the plurality of differential-mode inductors are connected in series in the phase lines, and the output terminals of the plurality of differential-mode inductors are connected to the input terminals of the two common-mode inductors; the two common-mode inductors are connected in parallel.

[0014] By adopting the above technical solution, multiple differential-mode inductors are connected in series in the three-phase input line, which can independently suppress differential-mode current fluctuations on each phase line and improve the system's adaptability to unbalanced loads. The cascaded use of differential-mode inductors helps to distribute thermal stress and magnetic saturation risks. The parallel structure of common-mode inductors can be equivalent to lower parasitic capacitance, which is beneficial to improving the common-mode impedance bandwidth. The output terminals of the differential-mode inductors are uniformly connected to the input terminals of the common-mode inductors, forming an ordered filtering path of "differential-mode first, then common-mode".

[0015] In a preferred embodiment of this application: the cutoff frequency of the second-order LC filter network Determined according to formula (1): (1) in, This represents the total inductance of the differential mode circuit. This represents the total capacitance of the differential mode circuit. The cutoff frequency The operating switching frequency of the frequency converter is set to ensure that the insertion loss is not less than 40dB at the operating switching frequency.

[0016] By adopting the above technical solution, the natural resonant frequency theory of the second-order low-pass filter shows that when the signal frequency is close to... At this point, the filter begins to significantly attenuate high-frequency components. Setting the cutoff frequency to the inverter's operating switching frequency (e.g., 10kHz) means that at this critical interference source frequency, the filter is at the beginning of its strong attenuation region, effectively suppressing switching noise generated by IGBT / PWM modulation. Furthermore, an insertion loss of no less than 40dB is required at this frequency, equivalent to attenuating the interference voltage to less than 1% of its original value, meeting the stringent limitations on conducted emissions from shipborne equipment in military standards such as GJB151B.

[0017] In a preferred embodiment of this application: the total inductance value of the differential mode circuit It has an inductance of 1.1mH and consists of three differential mode inductors connected in series, each with an inductance of 550μH. The total capacitance of the differential circuit The capacitance is 39.7 μF, consisting of six parallel differential-mode capacitors, each with a capacitance of 2.2 μF; the cutoff frequency... It is 10kHz.

[0018] By adopting the above technical solution, the total differential mode inductance is 1.1mH (composed of three 550μH inductors connected in series), and the total differential mode capacitance is 39.7μF (composed of six 2.2μF capacitors connected in parallel). The calculated cutoff frequency is 10kHz, which exactly matches the modulation frequency range of a typical ship wind turbine frequency converter.

[0019] In a preferred embodiment of this application: the operating switching frequency of the frequency converter is 100kHz, and the insertion loss of the filter circuit of the second-order LC filter network is... Determined according to formula (2): (2) Where k is the order of the filter circuit, and its value is 2; This is the test frequency.

[0020] By adopting the above technical solution, a value of 2 for k represents the second-order filtering characteristic. For example, when the inverter's operating frequency is 100kHz, i.e. When the value is 10, the theoretical insertion loss can reach 40dB, which is in high agreement with the measured results. This model can not only guide component selection, but also be used for fault diagnosis—if the measured value is significantly lower than the theoretical value, it indicates that there may be problems such as component aging, poor contact, or layout parasitic effects.

[0021] In a preferred embodiment of this application, the filtering circuit's suppression effect on lightning surge voltage clamped by the lightning protection circuit is characterized by the following voltage attenuation model based on the Laplace transform: in, This represents the peak surge voltage at the output of the filter circuit. The peak surge voltage at the output of the lightning protection circuit; The pulse width of the lightning surge waveform; This represents the total inductance of the filter circuit under the corresponding interference path. This represents the total capacitance of the filter circuit under the corresponding interference path.

[0022] By adopting the above technical solution, the voltage attenuation model reveals that the suppression mechanism of the filter circuit against lightning surges is not a simple "steady-state filtering," but a dynamic energy dissipation process. When fixed, increase and It can significantly reduce / The ratio refers to the surge suppression ratio; conversely, if component aging leads to a decrease in inductance or capacitance, the attenuation index decreases, the output surge peak increases, and the system's protection capability weakens. This application establishes a surge voltage attenuation mathematical model based on LC equivalent parameters, enabling quantitative analysis and dynamic characterization of the performance of integrated lightning protection filter components under transient overvoltage conditions, thereby improving the reliability and maintainability of the device in complex shipboard electromagnetic environments.

[0023] Specifically, the voltage decay model formula originates from the response behavior of a second-order RLC series circuit to transient excitation. When a lightning surge is injected into the system in the form of a high-steep voltage pulse, the LC network in the filter circuit forms a low-pass filter channel, possessing a natural ability to integrate and absorb high-frequency components. Since the resistance in the actual system is relatively small, the damping term can be approximately ignored. Therefore, this exponential decay model reflects the "smoothing and peak-shaving" effect of the LC structure on the surge voltage, that is, the output voltage decays exponentially with time, and the decay rate increases from... The larger this value is, the longer the system time constant, and the slower the response to rapidly changing signals, thus achieving a stronger voltage suppression effect.

[0024] Secondly, the objective of this invention is achieved through the following technical solution: A processing method for an integrated lightning protection filter component for a shipboard wind turbine frequency converter, applied to the integrated lightning protection filter component for a shipboard wind turbine frequency converter as described above, the method comprising: Obtain the circuit topology data and ship environment parameters of the integrated lightning protection filter component, and generate the topology model of the integrated lightning protection filter component according to the preset circuit component table; Obtain lightning protection parameters and filtering parameters, and generate a first simulation model to simulate the operating state of the device in a ship environment based on the topology model, the lightning protection parameters and the filtering parameters; Based on the topology model and the first simulation model, the ship's environmental impact parameters are integrated to generate a second simulation model for comparing and analyzing the lightning protection and filtering performance of the integrated lightning protection and filtering components. Based on the first simulation model and the second simulation model, a simulation test command is triggered to obtain the operation monitoring results of the device, which include the lightning protection effectiveness index and the filtering quality index.

[0025] By adopting the above technical solution, an accurate topology model is generated by analyzing circuit topology data and ship environmental parameters (such as salt spray concentration, vibration spectrum, and power grid fluctuations), providing a foundation for subsequent simulations. Then, a first simulation model is established by combining lightning protection and filtering parameters to simulate the dynamic response behavior of the device under typical operating conditions. Based on this, a second simulation model is generated by introducing ship environmental influencing factors, forming a comparison scenario between "ideal" and "real." Through collaborative simulation of the two models, the degree of influence of environmental factors on the device's performance can be separated, thereby obtaining comprehensive operational monitoring results including the lightning protection effectiveness index (reflecting surge suppression capability) and the filtering quality index (reflecting EMI suppression level). This enables forward-looking prediction of the performance degradation of the integrated lightning protection and filtering components throughout their entire lifecycle.

[0026] In a preferred embodiment of this application: the step of obtaining lightning protection parameters and filtering parameters, and generating a first simulation model for simulating the operating state of the device in a ship environment based on the topology model, the lightning protection parameters, and the filtering parameters, further includes: The lightning protection parameters include surge current capacity, response time parameters, and grounding resistance value; the filtering parameters include capacitance, inductance, and impedance matching parameters. Based on the lightning protection parameters and the filtering parameters, the comprehensive influence coefficient is calculated using a weight allocation method, which dynamically adjusts the weight values ​​based on the ship's environmental parameters. The integrated ship environmental impact parameters include: Based on the ship's environmental impact parameters, electromagnetic interference impact parameters and damp heat corrosion impact parameters are obtained; Based on the electromagnetic interference influence parameters and the damp heat corrosion influence parameters, the topology model is modified to generate a second topology model; Based on the second topology model and the first simulation model, the second simulation model is generated using the control variable method, wherein the control variable method includes fixing lightning protection parameters and variating filtering parameters.

[0027] By adopting the above technical solution, lightning protection parameters and filtering parameters are assigned different weights. These weights are dynamically adjusted based on real-time ship environmental parameters (such as humidity, temperature, and power grid harmonic content), reflecting the nonlinear impact of environmental sensitivity on system performance. For example, in high-humidity environments, grounding resistance may deteriorate; in this case, the weight of "grounding resistance value" in the comprehensive influence coefficient should be increased. By introducing electromagnetic interference and damp-heat corrosion influence parameters, the original topology model is physically degraded, generating a more realistic aging model (second topology model). Based on this, a second simulation model is generated using the controlled variable method. For example, by fixing the lightning protection parameters and only varying the filtering parameters, the impact of filter component aging on the system's EMI performance can be evaluated separately.

[0028] In a preferred embodiment of this application, the trigger simulation test command includes: Based on a preset ship environment frequency threshold, a frequency calibration command is triggered to unify the test frequency bands of the first simulation model and the second simulation model. The simulation test command is used to obtain a first test result and a second test result. The first test result is the lightning protection effectiveness index calculated based on the surge suppression rate, and the second test result is the filter quality index calculated based on the insertion loss and the ripple coefficient. Based on the comparison difference between the first test result and the second test result, the operation monitoring result is output, wherein when the comparison difference is greater than a preset threshold, an early warning signal is triggered.

[0029] By adopting the above technical solution, the frequency calibration command ensures that the first simulation model and the second simulation model are compared and tested in the same frequency band (e.g., 150kHz to 30MHz) and frequency point, eliminating misjudgments caused by inconsistent sampling. A preset ship environment frequency threshold (e.g., set according to GJB151B standard) serves as the test boundary condition. The first and second test results enable a quantitative evaluation of the device's dual functions. By comparing the differences, when the difference exceeds the preset threshold, it indicates that environmental stress has significantly affected the device's performance, thus achieving early fault identification capability.

[0030] In summary, this application includes at least one of the following beneficial technical effects: 1. By cascading the surge protection circuit and the filter circuit, and implementing an electromagnetic shielding isolation structure within a metal cavity, effective isolation is achieved against high-frequency interference such as switching noise and thunder pulses. This ensures that the transient large current generated when the surge protection module encounters a lightning surge will not interfere with the normal operation of the filter module through a common ground path or spatial coupling, thus avoiding the filtering performance degradation problem caused by electromagnetic crosstalk in traditional integrated devices. Using temperature-sensitive fuses and varistors as surge protection components, effective clamping of line-to-line and line-to-ground surge voltages is achieved, while also providing overheat self-break protection, improving the safety and reliability of the device under high-energy impacts. The second-order LC filter network significantly reduces the conducted interference level on the inverter input side through the synergistic suppression of differential-mode and common-mode noise. 2. This application establishes a surge voltage attenuation mathematical model based on LC equivalent parameters, thereby realizing the quantitative analysis and dynamic characterization of the performance of integrated lightning protection filter components under transient overvoltage conditions. This breaks through the limitations of traditional empirical design methods and improves the reliability and maintainability of the device in complex shipborne electromagnetic environments. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of an integrated lightning protection filter assembly for a ship's wind turbine frequency converter according to one embodiment of this application; Figure 2 This is a schematic diagram of the internal and external radiation attenuation at the connection between the metal housing and the cover plate of an integrated lightning protection filter assembly for a ship wind turbine frequency converter according to an embodiment of this application. Figure 3 This is a circuit diagram of the lightning protection circuit and the filtering circuit of an integrated lightning protection filter component for a ship wind turbine frequency converter according to one embodiment of this application; Figure 4 This is a diagram showing the effect of filtering before and after CE102 testing on the L1 phase line of the power line in an integrated lightning protection filter assembly for a ship wind turbine frequency converter according to an embodiment of this application. Figure 5 This is a diagram showing the effect of filtering before and after CE102 testing on the L2 phase line of the power line in an integrated lightning protection filter assembly for a ship wind turbine frequency converter according to an embodiment of this application. Figure 6 This is an embodiment of the present application showing the effect of space radiated emission RE102 testing of an integrated lightning protection filter component for a ship's wind turbine frequency converter in the H direction of the 10K-1G frequency band, before and after the filtering modification. Detailed Implementation

[0032] The present application will be further described in detail below with reference to the accompanying drawings.

[0033] In one embodiment, such as Figures 1 to 3 As shown, this application discloses an integrated lightning protection filter assembly for a ship's wind turbine frequency converter. The integrated lightning protection filter assembly includes a metal cavity, a lightning protection circuit, and a filter circuit; the lightning protection circuit and the filter circuit are cascaded.

[0034] The interior of the metal cavity is divided into a first compartment for accommodating surge protection circuits and a second compartment for accommodating filtering circuits; the first and second compartments form an electromagnetic shielding isolation structure. In actual design, the metal cavity also includes a third compartment. The input cable of the first compartment is fitted with a metal mesh anti-surge sleeve and potted with polyurethane adhesive with a thermal conductivity of 0.5 W / m·K to ensure an insulation resistance of not less than 100MΩ@1000Vdc. The third compartment can be used to accommodate power correction circuits, such as those including a rectifier bridge. Figure 2 As shown, the metal cavity consists of a metal shell with one end open and a cover plate. The cover plate covers the inner annular groove opened on the inner wall of the metal shell. The cross-section of the inner annular groove is right angled. When the electromagnetic waves inside the cavity radiate outward from the metal shell, they will be attenuated after refraction at the right angle, thus achieving a good shielding effect.

[0035] For example, the total length of the metal cavity compartment is set to 112.4 mm, and the gap width after the cover plate is installed is 0.1 mm. Based on the estimation formula for electromagnetic leakage through the pores:

[0037] Where SE is the attenuation value of the incident electromagnetic wave in dB; L is the gap length in mm; H is the gap width in mm; and f is the frequency of the incident electromagnetic wave in MHz. Substituting the switching frequency of 100kHz into the formula, we can see that the attenuation of the switching frequency signal after adding the partition can reach approximately 37dB, indicating a significant shielding effect. In this embodiment, the operating parameters of the integrated surge protection filter component include: input voltage range of 342Vac to 418Vac, rated current of 15A, operating temperature of -40℃ to +70℃, and meeting the 2500V surge test requirements of Appendix 300A of GJB4000-2000.

[0038] like Figure 3 As shown, with Figure 3 Taking the circuit diagram shown as an example, the surge protection circuit includes at least one temperature-sensitive fuse varistor configured to clamp line-to-line and line-to-ground surges of the input AC power supply. Specifically, the surge protection circuit includes a first varistor group, a second varistor group, an inter-line capacitor group, and a line-to-ground capacitor group. The first varistor group and the inter-line capacitor group are connected in parallel to form a line-to-line surge suppression branch. The inter-line capacitor group includes capacitors C10, C11, C12, C13, C14, and C15. The second varistor group and the line-to-ground capacitor group are connected in parallel to form a line-to-ground surge suppression branch. The line-to-ground capacitor group consists of common-mode capacitors C7, C8, and C9. Figure 3 As shown, the first varistor group includes multiple cascaded varistors of the TFMOV20S681 model, and the second varistor group includes multiple cascaded varistors of the TFMOV20S331 model. When the operating temperature of the first and second varistor groups reaches 136°C, the internal fuse automatically blows, cutting off the fault path and preventing thermal runaway. Figure 3 The main function of the multiple resistors R in the circuit is to provide a discharge circuit for capacitors C1 to C6 after the product is powered off, so as to prevent the product from being charged and causing harm to the human body.

[0039] The first varistor group operates at a voltage range of 400VAC to 680VAC, used to clamp a 2500VAC surge between lines to below 1120VAC. The second varistor group operates at a voltage range of 200VAC to 300VAC, used to clamp a 2500VAC surge between lines to ground to below 550VAC. Without triggering the back-end hardware comparison circuit, it outputs a shutdown voltage signal to the DSP (Digital Signal Processor), which then outputs a PWM square wave to shut down the rectifier MOSFET in the power correction circuit. The line-to-line capacitor bank and the line-to-ground capacitor bank are connected between phase lines L1, L2, and L3.

[0040] like Figure 3 As shown, with Figure 3 Taking the circuit diagram shown as an example, the filter circuit includes a second-order LC filter network with a cutoff frequency. The second-order LC filter network includes a differential-mode inductor, a common-mode inductor, a differential-mode capacitor, and a common-mode capacitor. The differential-mode inductor and the common-mode inductor are connected in series. The differential-mode capacitor and the common-mode capacitor are connected in parallel at the output terminal of the common-mode inductor. Figure 3 Inductors L3, L4, and L5 are differential-mode inductors, which return interference current to the switching power supply circuit and store and suppress it. Inductors L1 and L2 are common-mode inductors, which can be wound with cores of higher permeability. Capacitors C1 to C6 are differential-mode capacitors, providing a low-impedance return path for differential-mode interference. Capacitors C7 to C9 are common-mode capacitors, providing a low-impedance discharge path for common-mode signals.

[0041] The integrated surge protection filter component also includes: a differential-mode inductor group consisting of multiple differential-mode inductors, a differential-mode capacitor group consisting of two common-mode inductors and multiple differential-mode capacitors; the multiple differential-mode inductor groups are connected in series in the input path of the phase lines of the three-phase AC power supply; the multiple differential-mode inductors are connected in series on the phase lines, and the output terminals of the multiple differential-mode inductors are connected to the input terminals of the two common-mode inductors; the two common-mode inductors are connected in parallel, and the common-mode inductors are also called common-mode chokes. In this embodiment, the differential-mode inductor group includes differential-mode inductors L3, L4, and L5; the two common-mode inductors include inductors L1 and L2. The differential-mode capacitor group includes capacitors C1, C2, C3, C4, C5, and C6. Capacitors C7, C8, and C9 are common-mode capacitors.

[0042] The inverter operates at a switching frequency of 100kHz, and the insertion loss of the second-order LC filter network is... Determined according to formula (2): (2) Where k is the order of the filter circuit, and its value is 2; This is the test frequency.

[0043] Cutoff frequency of the second-order LC filter network Determined according to formula (1): (1) in, This represents the total inductance of the differential mode circuit. The total capacitance of the differential mode circuit; cutoff frequency. The inverter's operating switching frequency is set to ensure an insertion loss of at least 40dB at that frequency. The total inductance value of the differential mode circuit is also specified. The capacitance is 1.1mH (considering leakage inductance), consisting of three differential-mode inductors connected in series. Figure 3The differential mode inductors are L3, L4, and L5, each with an inductance of 550 μH. The total capacitance of the differential mode circuit is... The capacitance is 39.7 μF, consisting of six parallel differential-mode capacitors, each with a capacitance of 2.2 μF; cutoff frequency. It is 10kHz.

[0044] The effect of the filter circuit on suppressing the lightning surge voltage after it has been clamped by the lightning protection circuit is characterized by the following voltage attenuation model based on the Laplace transform:

[0045] in, This represents the peak surge voltage at the output of the filter circuit. The peak surge voltage at the output of the lightning protection circuit; The pulse width of the lightning surge waveform; This represents the total inductance of the filter circuit under the corresponding interference path. This represents the total capacitance of the filter circuit under the corresponding interference path.

[0046] Specifically, to further illustrate the filtering and lightning protection effect of the embodiments of this application, CE102 tests will be performed on the L1, L2, and L3 phase lines of the 380V power line, and RE102 tests will be performed on the radiated emissions in space, with the frequency band from 10kHz to 1GHz, divided into two directions, namely the V and H suffixes. Figure 4 , Figure 5 and Figure 6 As shown, Figure 4 The image shows the filtering effect of the integrated surge protection filter component of this application on the L1 phase line of a 380V power line before and after rectification. Figure 5 The images show the filtering effect of the integrated surge protection filter component of this application on the L2 phase line of a 380V power line before and after rectification. Figure 6 To conduct RE102 testing and monitoring of the space radiated emissions of the integrated surge protection filter component of this application for a 380V power line, Figure 6 The image shows the filter test results in the H direction of the 10K-1G frequency band before and after the rectification.

[0047] The implementation principle of an integrated lightning protection filter component for a ship's wind turbine frequency converter, as described in this application, is as follows: the lightning protection circuit and the filter circuit are cascaded, with the lightning protection circuit at the front end and the filter circuit at the rear end. This ensures that surges in the input AC power supply (such as line-to-line or line-to-ground surges) are first handled by the lightning protection circuit and then purified by the filter circuit. The interior of the metal cavity is divided into a first compartment (accommodating the lightning protection circuit) and a second compartment (accommodating the filter circuit), forming an electromagnetic shielding isolation structure. The cover plate of the metal cavity and the shell are fitted together by an inner annular groove (with a right angle in cross-section). When internal electromagnetic waves (such as noise generated by the frequency converter switching frequency of 100kHz) radiate outward, they will be refracted and reflected multiple times at the right angle, resulting in energy attenuation. According to the electromagnetic leakage formula for slots (SE is related to the slot length L, width H, and frequency f), the attenuation of a 100kHz signal can reach approximately 37dB. This effectively isolates the coupling of transient interference (such as large current surges from lightning strikes) generated by the lightning protection circuit to the filter circuit. The surge protection circuit uses a temperature-sensitive fuse varistor. When a line-to-line surge voltage or a line-to-ground surge voltage is input, the first and second varistor groups respond quickly to clamp the surge to a safe level (below 1120VAC and 550VAC, respectively). The varistor integrates a temperature-sensitive fuse. When the operating temperature reaches 136℃ (due to surge energy accumulation), the fuse melts, cutting off the fault path to achieve the overheat self-break protection mechanism of the varistor. Furthermore, the filter circuit uses a second-order LC filter network. The differential-mode inductor and common-mode inductor are connected in series, and the differential-mode capacitor and common-mode capacitor are connected in parallel to form a composite path. The differential-mode component suppresses noise between phase lines (such as switching harmonics), and the common-mode component suppresses ground-to-line noise (such as ground interference) to achieve the effect of synergistic suppression of differential-mode noise and common-mode noise. According to formula (2), the insertion loss of the second-order LC filter network at 100kHz is not less than 40dB, which means that the noise voltage is attenuated to 1 / 100 of the original value, significantly reducing the conducted interference level on the input side. The voltage decay model (based on Laplace transform) further quantifies the suppression effect of the filter circuit on the residual voltage of lightning surges.

[0048] In another embodiment, such as Figure 5 As shown, this application also discloses a processing method for an integrated lightning protection filter component used in a ship wind turbine frequency converter. This processing method for an integrated lightning protection filter component used in a ship wind turbine frequency converter is applied to such a component. The processing method for an integrated lightning protection filter component used in a ship wind turbine frequency converter specifically includes the following steps: S1: Obtain the circuit topology data and ship environment parameters of the integrated lightning protection filter component, and generate the topology model of the integrated lightning protection filter component according to the preset circuit component table.

[0049] In this embodiment, the integrated lightning protection filter component is an integrated lightning protection filter device. Circuit topology data refers to the spatial layout and electrical connection relationships of the first and second compartments within the metal cavity of the integrated lightning protection filter component. These electrical connections include the model, component layout, and wiring of each component (such as inductors, capacitors, varistors, and rectifiers), defining the flow paths of current and signals. Circuit topology data affects the EMC (electromagnetic compatibility) and performance of the integrated lightning protection filter component. Ship environmental parameters refer to the physical conditions in the ship's operating environment, including but not limited to engine room temperature, humidity, salt spray concentration, electromagnetic interference intensity, and ship electromagnetic environment level. The ship electromagnetic environment level can adopt the RE102 / CE102 limits specified in GJB 151B-2013. The preset circuit component table contains the technical specifications and performance parameters of all available components, such as rated voltage, current capacity, and response time.

[0050] Specifically, the SPICE models or equivalent circuit parameters of each component are retrieved from a pre-defined circuit component library. In simulation software (such as ANSYS Twin Builder or Siemens Simcenter AMESim), a three-dimensional hybrid simulation topology model containing the electrical characteristics and physical layout of all components is constructed based on the actual connection relationship of the integrated lightning protection filter component to be tested. The three-dimensional hybrid simulation topology model not only includes circuit connections but also integrates the electromagnetic shielding characteristics of the metal cavity.

[0051] S2: Obtain lightning protection parameters and filtering parameters, and generate a first simulation model based on the topology model, lightning protection parameters, and filtering parameters to simulate the operating state of the device in a ship environment.

[0052] In this embodiment, lightning protection parameters include, but are not limited to, surge current capacity, response time parameters, and grounding resistance values, which describe the characteristics of lightning protection components and reflect the protection capability of the lightning protection circuit. Filtering parameters include, but are not limited to, capacitance, inductance, and impedance matching parameters, which describe the characteristics of filtering components and determine the filtering effect. Surge current capacity is the maximum surge current value that the varistor can handle, in kA; response time parameter represents the time from surge detection to action of the varistor, in ns; grounding resistance value represents the resistance of the grounding path, in Ω. Capacitance represents the capacitance of the capacitor, in μF; inductance represents the inductance value of the inductor, in μH; impedance matching parameter represents the impedance matching value between the filter and the source / load, in Ω.

[0053] Specifically, lightning protection and filtering parameters can be obtained from the manufacturer's datasheet or actual measurements from testing equipment. The digital circuit diagram of the topology model can be obtained by opening the topology model file in simulation software (such as LTspice or PSpice) and manually or via script (a Python script calling the LTspice API) updating component properties. For example, the surge current capacity of the varistor can be set to 10kA, and the response time to 50ns.

[0054] In this embodiment, a dynamic first simulation model is generated using simulation software. The first simulation model includes component models and excitation sources for input ports. The component models contain various components of the integrated lightning protection and filtering components. Each component is generated by loading specific electrical parameters based on the topology model generated in step S1. For example, in ANSYS Twin Builder software, the lightning protection parameters and filtering parameters are assigned to the corresponding SPICE components in the topology model. For example, a nonlinear resistance model is used for the varistor, that is, a nonlinear volt-ampere characteristic curve is set for the TMOV20S681 varistor so that it exhibits a low resistance state above 420VAC. A model with saturation characteristics is used for the inductor, that is, a core model with a saturation current of 20A is set for the 550μH inductor. The excitation sources include surge pulse sources and noise sources to simulate real interference. Then, excitation sources were added to the input port of the model: a 2500VAC, 2Ω internal resistance, 1.2 / 50μs pulse generator conforming to GJB 4000-2000 standard was used to simulate line-to-line surge, and a 100kHz, 60A square wave current source was used to simulate inverter switching noise.

[0055] The first simulation model can run simulations to demonstrate the dynamic response of integrated lightning protection filter components in a "baseline" ship environment (i.e., without environmental degradation factors); the output results include waveforms of current, voltage, etc., and performance indicators such as surge suppression rate and insertion loss. As a virtual test model, the first simulation model simulates the operating state of the integrated lightning protection filter components in a ship environment.

[0056] Furthermore, step S2 also includes: S201: The comprehensive influence coefficient is calculated using a weighted allocation method based on lightning protection parameters and filtering parameters. The weighted allocation method dynamically adjusts the weight values ​​based on ship environmental parameters.

[0057] In this embodiment, a weighted allocation method is used to assign weights to the lightning protection parameters and filtering parameters, and a comprehensive score (i.e., comprehensive influence coefficient) is calculated to quantify the relative importance of each parameter to the overall system performance. The comprehensive influence coefficient is a dimensionless value, usually ranging from 0 to 1. The larger the value, the smaller the negative impact (or the greater the positive impact) of the parameter combination on the system performance.

[0058] Specifically, initial weighting coefficients are pre-assigned to each lightning protection parameter and filtering parameter. For example, the initial weight of surge current capacity is 0.3, and the weight of response time is 0.2. The weight values ​​can be dynamically adjusted according to the ship's environmental parameters. The specific dynamic adjustment rules can be achieved using an adjustment algorithm or by looking up a preset weight adjustment table. For example, if the temperature is >50℃, the weight of the grounding resistance value is increased (from 0.2 to 0.4) because high temperature accelerates corrosion; if the salt spray concentration is >2mg / m³, the weight of the capacitance is increased (from 0.1 to 0.3) because salt spray affects the stability of the capacitor.

[0059] For example, the environmental parameters of a ship include ambient temperature T (in °C, ranging from 25 to 70), relative humidity H (in %, ranging from 60 to 95), and salt spray concentration S (in mg / m³, ranging from 0.5 to 5.0). The target parameters to be evaluated are surge current capacity I (in kA, ranging from 10 to 20) and grounding resistance R (in Ω, ranging from 0.1 to 2.0). The reason is that surge current capacity I affects lightning protection capability, and grounding resistance R affects surge discharge efficiency.

[0060] Based on expert experience and knowledge, an initial weight matrix is ​​set for the ship's environmental parameters on the target parameters. : in, This indicates that temperature has an initial weighting of 30% on surge current capacity. This indicates that humidity has an initial weight of 30% on the grounding resistance value; This indicates that the initial weight of the smoke concentration on the grounding resistance value is 20%. And so on.

[0061] The weight adjustment rule is to dynamically amplify the weights based on how much the environmental parameters exceed the threshold: Where x is the current environment parameter value, Use a baseline value, such as an initial ambient temperature baseline value of 25℃; This represents the maximum fluctuation range of the parameter. This is the magnification factor, which can be set to 1.1-1.7, but is usually set to 1.5. The specific value can be customized as needed.

[0062] For example, the temperature weighting is adjusted to The temperature of 77.5℃ is the average temperature; the salt spray weight is adjusted to... The adjusted weight matrix is ​​as follows: Overall Influence Coefficient The calculation formula is: ,in These are normalized values ​​for environmental parameters, ranging from 0 to 1. For example... , , Next, we will calculate the surge current capacity influence coefficient item by item. : ; Calculate the influence coefficient of grounding resistance value : .

[0063] The surge current capacity and grounding resistance values ​​are corrected and integrated into the simulation model. The formula for calculating the corrected surge current capacity value is as follows: The attenuation coefficient λ is 0.2. For the simulated surge current capacity; This refers to the nominal surge current capacity. The formula for calculating the correction value of the grounding resistance is: The growth coefficient The value is 0.3; This is the simulated grounding resistance value; This is the nominal grounding resistance value. It is calculated using an exponential function. and linear functions Degradation is characterized by exponential decay (surge capacity) and linear growth (resistance), respectively.

[0064] S3: Based on the topology model and the first simulation model, integrate the ship's environmental influence parameters to generate a second simulation model for comparing and analyzing the lightning protection and filtering performance of the integrated lightning protection filter components.

[0065] In this embodiment, the ship environmental impact parameters refer to external environmental factors that can lead to performance degradation or failure of electronic components, including electromagnetic interference impact parameters and damp heat corrosion impact parameters. When constructing the second simulation model, the impact of factors such as electromagnetic interference and damp heat corrosion can be considered, and relevant parameters in the second simulation model can be adjusted or new variables can be added. The second simulation model is based on the topology model of step S1 and the first simulation model generated in step S2, and further integrates the environmental degradation effects during service to generate a more realistic second simulation model, which considers the performance degradation factors of the integrated lightning protection filter component of the ship's wind turbine frequency converter in the actual service environment.

[0066] Specifically, the integrated ship environmental impact parameters in step S3 include: S31: Based on the ship's environmental impact parameters, obtain the electromagnetic interference impact parameters and the damp heat corrosion impact parameters.

[0067] In this embodiment, the electromagnetic interference (EMI) parameters include electric field strength (typically 1-100 V / m), magnetic field strength (unit: A / m), and frequency range (e.g., 10 kHz-1 GHz), which can be obtained from the ship's EMI monitoring system. The damp heat corrosion parameters include corrosion rate and insulation aging factor. The corrosion rate is measured in mm / year, with a typical value of 0.01-0.5 mm / year. The insulation aging factor, such as the rate of decrease in insulation resistance, can be detected by sensors or predicted using corrosion models such as those in ISO 9223. The collected EMI and damp heat corrosion parameters are normalized and scaled to a range of 0-1.

[0068] S32: Based on the electromagnetic interference influence parameters and the damp heat corrosion influence parameters, the topology model is modified to generate a second topology model.

[0069] In this embodiment, the correction of the topology model includes: correcting the component values ​​in the topology model based on the ship's environmental influence parameters. For example, in a high salt spray environment, the equivalent series resistance (ESR) of the capacitor increases, so a series resistance component is added to the model; in a humid and hot environment, the inductance permeability decreases, so the inductance value is reduced. For example, the formula L=L0×(1-α1×ΔRH can be used, where L is the corrected inductance value, L0 is the inductance value before correction, α1 is the humidity coefficient, and ΔRH is the change in relative humidity.

[0070] Specifically, in the revised topology model, electromagnetic interference (EMI) and damp-heat corrosion (DCH) modeling are performed. EMI modeling involves superimposing a broadband random noise source on the power input line, with a power spectral density conforming to 80% of the RE102 standard limit and a frequency range of 30MHz to 1GHz, simulating radiated interference generated by shipborne radar, communication equipment, and other components in a real electromagnetic environment. DCH modeling employs the Arrhenius accelerated aging model to predict the corrosion depth of connection points over a 10-year service life. Accordingly, an equivalent series resistance (ESR) is added to all solder joints and screw connections in the simulation model, initially at 0.1mΩ, increasing to 5mΩ after 10 years of corrosion, to simulate voltage drop and heat generation caused by poor contact. The DCH degradation effect of the integrated lightning protection filter component in a real service environment is simulated to obtain the second topology model.

[0071] S33: Based on the second topology model and the first simulation model, the second simulation model is generated by the control variable method, which includes fixing the lightning protection parameters and variating the filtering parameters.

[0072] In this embodiment, simulation software is used to combine the second topology model with the first simulation model. For example, in ANSYS Electronics, the second topology model is imported, and a comparative simulation is set up using the controlled variable method. For instance, the controlled variable method is used to generate the second simulation model by changing only one or a set of variables while keeping the first simulation model unchanged. For example, with lightning protection parameters fixed (such as the TMOV parameter of the varistor unchanged), the capacitance of differential mode capacitors C1~C6 is reduced from 2.2μF to 1.8μF (e.g., simulating electrolyte drying), and its impact on the 100kHz insertion loss is studied. Similarly, with filter parameters fixed, the grounding resistance is increased from 0.08Ω to 0.5Ω to simulate grounding loosening, and its impact on line-to-ground surge residual voltage is studied. By comparing the second simulation model with the first simulation model, it is possible to clearly analyze which components are most likely to become bottlenecks in system performance after long-term service.

[0073] Specifically, the second simulation model uses the circuit structure and parameters of the second topology model to run the simulation. The second simulation model is generated based on the first simulation model by loading "component parameters corrected for environmental degradation" and / or "boundary conditions including external disturbances".

[0074] For example, based on the first simulation model, a second simulation model is generated by gradually changing the coefficients after environmental degradation correction using the controlled variable method. The specific operation is as follows: A second simulation model A was generated: Keeping the lightning protection parameters (TMOV parameters), filter inductors (L3~L5, L1, L2) and grounding resistance unchanged, only the capacitance values ​​of the six differential-mode capacitors (C1~C6) were modified from 2.2μF to 1.8μF, and their equivalent series resistance was modified from 10mΩ to 50mΩ. This was used to separately analyze the impact of capacitor aging on the insertion loss of the filter performance.

[0075] Generate a second simulation model B: Keep all filtering parameters unchanged, only modify the system grounding resistance value from 0.08Ω to 0.5Ω (simulating grounding point looseness or corrosion) to analyze the impact of poor grounding on line-to-ground surge residual voltage of lightning protection performance separately.

[0076] Generate the second simulation model C: Keep all component parameters unchanged, and only activate the electromagnetic interference source added in step 2 at the input port. This model is used to analyze the impact of external electromagnetic interference on the background noise and sampling accuracy of the integrated lightning protection filter component.

[0077] S4: Based on the first simulation model and the second simulation model, trigger the simulation test command to obtain the operation monitoring results of the device. The operation monitoring results include the lightning protection effectiveness index and the filter quality index.

[0078] In this embodiment, triggering the simulation test command refers to setting a series of test scenarios, including different input conditions (such as surge voltages of different amplitudes), different combinations of environmental parameters, and preset ship environment frequency thresholds (such as 100kHz, corresponding to the frequency converter switching frequency), to trigger the calibration program. The lightning protection effectiveness index is calculated based on the surge suppression rate, with the formula: Surge suppression rate = (Input surge voltage - Output surge voltage) / Input surge voltage × 100%. The higher the index value (e.g., >95%), the better the lightning protection performance. Specifically, the peak values ​​of the input and output surge voltages are extracted from the simulation results, the surge suppression rate for each test scenario is calculated, and then the average value is taken as the lightning protection effectiveness index. The filter quality index is based on the insertion loss of the filter circuit. (Calculated according to formula (2)); The ripple coefficient represents the output ripple size, in %, with a typical value of <5%. Ripple coefficient = (output ripple peak value / output average voltage) × 100%, filter quality index = α × insertion loss + β × (1 - ripple coefficient), where α and β are weighting coefficients, for example, α = 0.7, β = 0.3.

[0079] Specifically, the insertion loss value (calculated at 100kHz) is obtained from the AC analysis results, and the output ripple data is obtained from the transient analysis results. The exponent is calculated using a weighted average method. The weights α and β can be adjusted according to the application scenario. For example, in a shipboard environment where insertion loss is of greater concern, α can be set to 0.8.

[0080] In this embodiment, the command to trigger the simulation test includes: S41: Based on the preset ship environment frequency threshold, trigger the frequency calibration command to unify the test frequency bands of the first simulation model and the second simulation model.

[0081] In this embodiment, the preset ship environment frequency threshold is 100kHz, corresponding to the operating switching frequency of the frequency converter. The frequency calibration command is triggered by using an automated script (Python or MATLAB script) to detect the current simulation settings and compare the frequency band settings of the first and second models. If the frequency bands are inconsistent, the script automatically triggers the calibration command. For example, in LTspice, the .step command is used to adjust the sampling frequency. During calibration, the test frequency band can be uniformly set to 100kHz ± 10% to ensure coverage of the frequency converter harmonics.

[0082] During calibration, adjust the sampling frequency setting and bandwidth limit in the simulation parameters. The sampling frequency can be set to a multiple of the frequency threshold, such as 200kHz. For bandwidth limits, in AC analysis, the frequency scan range can be set from 10Hz to 1MHz, but the focus is on analyzing the 100kHz frequency point. Frequency calibration commands are executed through the simulation software's API.

[0083] S42: Obtain the first test result and the second test result through the simulation test command. The first test result is the lightning protection effectiveness index calculated based on the surge suppression rate, and the second test result is the filter quality index calculated based on the insertion loss and ripple coefficient.

[0084] In this embodiment, the test scenarios include surge testing and noise testing. During surge testing, a standard surge waveform (such as an 8 / 20μs pulse) with an amplitude ranging from 1kV to 5kV (in 1kV steps) is input to simulate different lightning strike intensities. During noise testing, a Gaussian white noise signal with a frequency range of 10Hz-1MHz is input to simulate electromagnetic interference from ships.

[0085] S43: Based on the comparison difference between the first test result and the second test result, output the operation monitoring result. When the comparison difference is greater than the preset threshold, trigger the warning signal.

[0086] In this embodiment, the monitoring results can be output in report form, including test indicators such as index values, percentage difference, and performance rating. The difference calculation is performed by calculating the percentage difference between the lightning protection effectiveness index of the first test result and the filtering quality index of the second test result. The formula is: Percentage Difference = |(Second Model Value - First Model Value)| / First Model Value × 100%. Specifically, the index values ​​of the two models are read from the database. For example, if the lightning protection effectiveness index of the first model is 90% and the second model is 85%, the percentage difference = |85 - 90| / 90 × 100% = 5.56%. Preset thresholds can be set based on historical data or standards, such as a lightning protection effectiveness difference threshold of 10% and a filtering quality difference threshold of 15%. The thresholds are stored in a configuration file and can be adjusted as needed.

[0087] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0088] In one embodiment, particularly according to an embodiment of the invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, embodiments of the invention include a computer program product comprising a computer program / instructions that, when executed by a processor, implement the steps of a processing method for an integrated lightning protection filter assembly for a shipboard wind turbine frequency converter. In such embodiments, the computer program can be downloaded and installed from a network via a communication module, and / or installed from a removable medium. When the computer program is executed by a central processing unit (CPU), it performs the various functions defined in this invention.

[0089] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0090] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An integrated lightning protection filter assembly for shipboard wind turbine frequency converters, characterized in that, include: Metal cavity, lightning protection circuit and filter circuit; The lightning protection circuit and the filter circuit are cascaded. The interior of the metal cavity is divided into a first compartment for accommodating lightning protection circuits and a second compartment for accommodating filtering circuits, the first compartment and the second compartment forming an electromagnetic shielding isolation structure; The surge protection circuit includes at least one temperature-sensitive fuse varistor configured to clamp line-to-line surges and line-to-ground surges of the input AC power supply; The filtering circuit includes a second-order LC filter network with a cutoff frequency. The second-order LC filter network includes a differential-mode inductor, a common-mode inductor, a differential-mode capacitor, and a common-mode capacitor. The differential-mode inductor and the common-mode inductor are connected in series. The differential-mode capacitor and the common-mode capacitor are connected in parallel at the output terminal of the common-mode inductor.

2. The integrated lightning protection filter assembly for a shipboard wind turbine frequency converter according to claim 1, characterized in that, The surge protection circuit includes a first varistor group, a second varistor group, an inter-line capacitor group, and an inter-ground capacitor group. The first varistor group and the inter-line capacitor group are connected in parallel to form an inter-line surge suppression branch; the second varistor group and the inter-ground capacitor group are connected in parallel to form an inter-ground surge suppression branch; the operating voltage range of the first varistor group is 400VAC to 680VAC, and the operating voltage range of the second varistor group is 200VAC to 300VAC; the inter-line capacitor group and the inter-ground capacitor group are connected between phase lines L1, L2, and L3.

3. The integrated lightning protection filter assembly for shipboard wind turbine frequency converters according to claim 1, characterized in that, Also includes: The system comprises a differential-mode inductor group consisting of multiple differential-mode inductors, two common-mode inductors, and a differential-mode capacitor group consisting of multiple differential-mode capacitors; the multiple differential-mode inductor groups are connected in series in the input path of the phase lines of the three-phase AC power supply; the multiple differential-mode inductors are connected in series in the phase lines, and the output terminals of the multiple differential-mode inductors are connected to the input terminals of the two common-mode inductors; the two common-mode inductors are connected in parallel.

4. An integrated lightning protection filter assembly for a shipboard wind turbine frequency converter according to claim 3, characterized in that, The cutoff frequency of the second-order LC filter network Determined according to formula (1): （1） in, This represents the total inductance of the differential mode circuit. This represents the total capacitance of the differential mode circuit. The cutoff frequency The operating switching frequency of the frequency converter is set to ensure that the insertion loss is not less than 40dB at the operating switching frequency.

5. An integrated lightning protection filter assembly for a shipboard wind turbine frequency converter according to claim 4, characterized in that, The total inductance of the differential mode circuit It has a capacitance of 1.1mH and consists of three differential mode inductors connected in series, each with an inductance of 550μH. The total capacitance of the differential circuit The capacitance is 39.7 μF, consisting of six parallel differential-mode capacitors, each with a capacitance of 2.2 μF; the cutoff frequency... It is 10kHz.

6. An integrated lightning protection filter assembly for a shipboard wind turbine frequency converter according to claim 5, characterized in that, The inverter operates at a switching frequency of 100kHz, and the insertion loss of the second-order LC filter network is... Determined according to formula (2): （2） Where k is the order of the filter circuit, and its value is 2; This is the test frequency.

7. An integrated lightning protection filter assembly for a shipboard wind turbine frequency converter according to claim 3, characterized in that, The filtering circuit's suppression effect on lightning surge voltage clamped by the lightning protection circuit is characterized by the following voltage attenuation model based on the Laplace transform: in, This represents the peak surge voltage at the output of the filter circuit. The peak surge voltage at the output of the lightning protection circuit; The pulse width of the lightning surge waveform; This represents the total inductance of the filter circuit under the corresponding interference path. This represents the total capacitance of the filter circuit under the corresponding interference path.

8. A method for processing an integrated lightning protection filter assembly for a ship's wind turbine frequency converter, characterized in that, The method, applied to an integrated lightning protection filter assembly for a shipboard wind turbine frequency converter as described in any one of claims 1 to 7, comprises: Obtain the circuit topology data and ship environment parameters of the integrated lightning protection filter component, and generate the topology model of the integrated lightning protection filter component according to the preset circuit component table; Obtain lightning protection parameters and filtering parameters, and generate a first simulation model to simulate the operating state of the device in a ship environment based on the topology model, the lightning protection parameters and the filtering parameters; Based on the topology model and the first simulation model, the ship's environmental impact parameters are integrated to generate a second simulation model for comparing and analyzing the lightning protection and filtering performance of the integrated lightning protection and filtering components. Based on the first simulation model and the second simulation model, a simulation test command is triggered to obtain the operation monitoring results of the device, which include the lightning protection effectiveness index and the filtering quality index.

9. A processing method for an integrated lightning protection filter assembly for a ship's wind turbine frequency converter according to claim 8, characterized in that, The step of acquiring lightning protection parameters and filtering parameters, and generating a first simulation model for simulating the operating state of the device in a ship environment based on the topology model, the lightning protection parameters, and the filtering parameters, further includes: The lightning protection parameters include surge current capacity, response time parameters, and grounding resistance value; the filtering parameters include capacitance, inductance, and impedance matching parameters. Based on the lightning protection parameters and the filtering parameters, the comprehensive influence coefficient is calculated using a weight allocation method, which dynamically adjusts the weight values ​​based on the ship's environmental parameters. The integrated ship environmental impact parameters include: Based on the ship's environmental impact parameters, electromagnetic interference impact parameters and damp heat corrosion impact parameters are obtained; Based on the electromagnetic interference influence parameters and the damp heat corrosion influence parameters, the topology model is modified to generate a second topology model; Based on the second topology model and the first simulation model, the second simulation model is generated using the control variable method, wherein the control variable method includes fixing lightning protection parameters and variating filtering parameters.

10. A processing method for an integrated lightning protection filter assembly for a ship's wind turbine frequency converter according to claim 8, characterized in that, The trigger simulation test command includes: Based on a preset ship environment frequency threshold, a frequency calibration command is triggered to unify the test frequency bands of the first simulation model and the second simulation model. The simulation test command is used to obtain a first test result and a second test result. The first test result is the lightning protection effectiveness index calculated based on the surge suppression rate, and the second test result is the filter quality index calculated based on the insertion loss and the ripple coefficient. Based on the comparison difference between the first test result and the second test result, the operation monitoring result is output, wherein when the comparison difference is greater than a preset threshold, an early warning signal is triggered.

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