A method and system for grading transient electromagnetic interference of a ship power grid

Abstract

The application discloses a kind of warship power grid transient electromagnetic interference grading evaluation method and system, it is related to warship power grid safety evaluation technical field, realize the scientific grading evaluation of warship power grid transient peak interference, provide reliable basis for the stable operation and equipment protection of warship power grid.It includes the following steps: using peak signal conduction sensitivity test, determine equipment transient peak sensitive threshold value.According to the importance of equipment, the importance coefficient of equipment is valued;Weighted average method is used to calculate the weighted average sensitive threshold value of the load equipment at the back end of distribution box.In the output end of the cabin distribution box of warship power grid, the transient peak conduction emission detection device is used to monitor and collect power grid transient peak conduction emission data in real time, and the power grid transient peak interference measurement value is identified from the data.The difference between the power grid transient peak interference measurement value and the weighted average sensitive threshold value is calculated;According to the difference result, the grading evaluation of warship power grid transient peak interference is carried out.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ship power grid safety evaluation, and particularly relates to a ship power grid transient electromagnetic interference grading evaluation method and system. BACKGROUND

[0002] In the ship power system and power grid, transient peak interference is an important factor affecting the normal operation of ship electronic and electrical systems and equipment. Important system equipment such as sonar, navigation, and ship maneuvering may degrade in performance or work abnormally due to transient peak interference, and may even cause safety accidents of the ship. The ship power grid structure is complex, the power generation system and the power distribution system have special mechanisms, and the load equipment connected behind the distribution boxes in each cabin has various types. The source end and the load end of the power grid generate various intensity transient peak interference signals from time to time during the ship operation, which may cause equipment malfunction, performance degradation, or even damage, seriously threatening the safety of ship navigation and the stability of the power system operation.

[0003] At present, the detection of transient peak interference of the ship power grid is mainly based on single index detection according to standards, and there is a lack of comprehensive, systematic, and diversified evaluation method that can reflect the importance of load equipment to the safety and technical and tactical indicators of the ship. The transient peak interference of the ship power grid cannot be scientifically graded, and it is difficult to meet the demand of the ship for accurate evaluation and effective prevention and control of the power grid transient peak interference. SUMMARY

[0004] Therefore, the present application provides a ship power grid transient electromagnetic interference grading evaluation method and system, which realizes scientific grading evaluation of the transient peak interference of the ship power grid, provides a reliable basis for stable operation of the ship power grid and equipment protection, and ensures safe operation of the ship.

[0005] To achieve the above purpose, the technical scheme of the ship power grid transient electromagnetic interference grading evaluation method of the present application comprises the following steps:

[0006] Step 1: A peak signal conduction sensitivity test is used to apply different intensity simulated transient peak interference signals to the common network load equipment behind the cabin distribution box of the ship power grid one by one, and the transient peak sensitivity threshold of the equipment is determined.

[0007] Step 2: The equipment is classified and importance coefficient is assigned according to the importance of the equipment.

[0008] The weighted average sensitivity threshold of the load equipment behind the distribution box is calculated by using the weighted average method with the importance coefficient as the weight in combination with the transient peak sensitivity threshold and the importance coefficient assignment of each equipment.

[0009] Step 3: Real-time monitoring and collecting the transient spike conduction emission data of the power grid at the output end of the cabin distribution box of the ship power grid, and identifying the grid transient spike interference measurement value from the data.

[0010] Step 4: Comparing the grid transient spike interference measurement value with the weighted average sensitivity threshold, calculating the difference between the two; according to the difference result, carrying out the classification evaluation of the ship power grid transient spike interference.

[0011] Further, step 1 is specifically: for the common network load equipment at the back end of the cabin distribution box of the ship power grid, injecting a transient spike signal, the pulse width of the transient spike signal is 10us±20%, the amplitude of the transient spike signal is V P , and the amplitude is increased in turn by 400V, 450V, 500V, 550V, 600V, 650V, 700V, 750V, 800V, 850V, 900V, each amplitude transient spike signal injection time is not less than 10min, and the phase of the transient spike signal is adjusted at the same time. When performance abnormalities or failures occur, record the interference signal threshold level, i.e. the sensitivity threshold of the equipment; the equipment that does not appear electromagnetic interference phenomenon during the test is recorded with the maximum value 900V as the sensitivity threshold.

[0012] Further, in step 2, the equipment is classified and importance coefficient is assigned according to the importance of the equipment, specifically: the equipment is classified into class I equipment-class III equipment according to its importance; the importance coefficient assignment range is set to 1-10; class I equipment is the highest important equipment class on the ship, and class I equipment will cause physical damage to the subsystem or equipment and affect the performance and safety of the whole ship after being subjected to transient spike electromagnetic interference; the importance coefficient w i of class I equipment is set to 1-3; class II equipment refers to: after being subjected to transient spike electromagnetic interference, it will cause the working performance of the subsystem or equipment to decrease or fail, and only make the system unable to complete part of the function without affecting the system and personnel safety; the importance coefficient w i of class II equipment is set to 4-6; class III equipment refers to: after being subjected to transient spike electromagnetic interference, only the working performance of the subsystem and equipment decreases without failure; or even if a failure is caused, the working state is restored after maintenance within a certain period of time without causing the system equipment to lose function; the importance coefficient w i of class III equipment is set to 7-10.

[0013] Further, in step 2, the calculated weighted average sensitivity threshold of the main load equipment at the back end of the distribution box is : ; wherein S i is the sensitivity threshold of the i-th load equipment, and w iis the importance coefficient of the ith load device.

[0014] Further, in step 3, the transient spike conduction emission detection device is applied to the output end of the ship power grid cabin distribution box to monitor and collect the power grid transient spike conduction emission data in real time, and the monitoring and collecting process is specifically as follows:

[0015] The monitoring and collecting time is not less than one sea voyage of the ship.

[0016] During the monitoring and collecting process, the sonar and other low-frequency emission devices on the ship should emit at full power for not less than 2 times; the radio frequency emission devices should emit at rated power for not less than 2 times, and the emission frequency is taken at 2 frequency points within the respective working frequency bands.

[0017] The microwave emission device emits at full power for not less than 2 times.

[0018] The high-power devices with power exceeding the set value, such as high-pressure air compressors, bilge pumps, ship hydraulic pumps, and propellers, are started, worked, stopped or switched between running states for not less than 2 times.

[0019] Further, in step 3, for monitoring and collecting the power grid transient spike conduction emission data, the power grid transient spike interference measurement value is identified therefrom, and the specific method is as follows:

[0020] For the transient spike interference signals monitored and collected, according to the parameters of the obtained transient spike interference signals including intensity, pulse width, and occurrence frequency, the peak value detection and statistical analysis method is adopted to extract the maximum value from the time-varying signal sequence, and the power grid transient spike interference peak value V is identified in combination with the frequency spectrum characteristics and energy distribution of the transient spike signal. PEAK .

[0021] The power grid transient spike interference measurement value is:

[0022] .

[0023] Further, step 4: compare the power grid transient spike interference measurement value with the weighted average sensitivity threshold value, calculate the difference value; according to the difference value, carry out the classification evaluation of the power grid transient spike interference of the ship, which is specifically as follows:

[0024] Compare the power grid transient spike interference measurement value dBV with the weighted average sensitivity threshold value , calculate the difference value =dBV- , according to the difference value, carry out the classification evaluation of the power grid transient spike interference of the ship according to the following. When <-30dB: no risk level; the load devices of the power grid cabin distribution box can work normally and generally no electromagnetic interference occurs. When in the interval of -30dB~ -6dB: low risk level; the electromagnetic interference risk on the ship is controllable. When in the interval of -6dB~0dB: medium risk level; there is a transient peak electromagnetic interference risk hidden danger on the ship; When in the interval of >0dB: high risk level; there is potential or existing electromagnetic interference on the ship.

[0025] Another aspect of the embodiment of the application further provides a ship power grid transient electromagnetic interference grading evaluation system, comprising the following modules:

[0026] A sensitive threshold determination module is used to adopt a peak signal conduction sensitivity test to apply different intensity simulated transient peak interference signals to the common network load devices at the rear end of the cabin distribution box of the ship power grid one by one, and to determine the transient peak sensitivity threshold of the devices; specifically, for the common network load devices at the rear end of the cabin distribution box of the ship power grid, a transient peak signal is injected, the transient peak signal pulse width is 10us±20%, the transient peak signal amplitude V P The amplitude test is sequentially increased at 400V, 450V, 500V, 550V, 600V, 650V, 700V, 750V, 800V, 850V and 900V, each amplitude transient peak signal injection time is not less than 10min, and the phase of the transient peak signal is adjusted at the same time; when performance abnormalities or failures occur, the interference signal threshold level, i.e. the sensitive threshold of the device, is recorded; the sensitive threshold of the device which does not appear electromagnetic interference phenomenon in the test process is recorded as the maximum value 900V.

[0027] A weighted average sensitive threshold calculation module is used to classify the devices according to the importance of the devices and assign importance coefficients to the devices; the transient peak sensitive threshold of each device obtained in the sensitive threshold determination module and the importance coefficient assignment are combined, the importance coefficient is used as the weight, and the weighted average method is used to calculate the weighted average sensitive threshold of the load devices at the rear end of the distribution box, specifically:

[0028]

[0029] Wherein, S is the calculated weighted average sensitive threshold of the main load devices at the rear end of the distribution box, S i is the sensitive threshold of the i-th load device, w i is the importance coefficient of the i-th load device; the devices are divided into class I devices~class III devices according to the importance thereof.

[0030] The importance coefficient assignment range is set to 1-10.

[0031] Class I equipment is the most important equipment on the ship, and the class I equipment will cause physical damage to the subsystem or equipment and affect the performance and safety of the whole ship after being subjected to transient peak electromagnetic interference; the importance coefficient w of the class I equipment is set i The value range is set to 1-3.

[0032] Class II equipment refers to the equipment that will cause the working performance of the subsystem or equipment to decrease or fail, and only make the system unable to complete part of the function without affecting the system and personnel safety after being subjected to transient peak electromagnetic interference; the importance coefficient w of the class II equipment is set i The value range is set to 4-6.

[0033] Class III equipment refers to the equipment that will only cause the working performance of the subsystem and equipment to decrease without failure, or even cause failure, but the working state will be restored after maintenance within a certain time without causing the system equipment to lose function; the importance coefficient w of the class III equipment is set i The value range is set to 7-10.

[0034] The power grid transient peak interference measurement value identification module is used to monitor and collect power grid transient peak conducted emission data in real time at the output end of the cabin distribution box of the ship power grid by using a transient peak conducted emission detection device, and to identify the power grid transient peak interference measurement value from the data.

[0035] The evaluation module is used to compare the power grid transient peak interference measurement value with the weighted average sensitivity threshold, calculate the difference between the two, and carry out classification evaluation of the ship power grid transient peak interference according to the difference result.

[0036] Further, in the power grid transient peak interference measurement value identification module, the power grid transient peak conducted emission data is monitored and collected in real time at the output end of the cabin distribution box of the ship power grid by using a transient peak conducted emission detection device, and the monitoring and collecting process is specifically as follows:

[0037] The time for monitoring and collecting emission data is not less than one sea voyage of the ship.

[0038] During the monitoring and collecting process, the sonar and other low-frequency emission equipment on the ship should emit at full power for not less than 2 times; the radio frequency emission equipment should emit at rated power for not less than 2 times, and the emission frequency is taken at 2 frequency points within the respective working frequency band.

[0039] The microwave emission equipment should emit at full power for not less than 2 times.

[0040] The high-power equipment with power exceeding the set value should be started, worked, stopped or switched between running states for not less than 2 times; the high-power equipment includes high-pressure air compressor, cabin bottom pump, ship hydraulic pump and propeller.

[0041] In the power grid transient peak interference measured value identification module, for monitoring and collecting power grid transient peak conduction emission data, the power grid transient peak interference measured value is identified therefrom, and the specific mode is as follows:

[0042] For the transient peak interference signal monitored and collected, according to the parameters of the transient peak interference signal, including intensity, pulse width, and occurrence frequency, a peak detection and statistical analysis method is used to extract the maximum value from the time-varying signal sequence, and the power grid transient peak interference peak value V is identified in combination with the frequency spectrum characteristics and energy distribution of the transient peak signal. PEAK .

[0043] Then the power grid transient peak interference measured value is: .

[0044] Further, the evaluation module, specifically: comparing the power grid transient peak interference measured value dBV with the weighted average sensitive threshold , calculating the difference value =dBV- , according to the difference value, the ship power grid transient peak interference classification evaluation is carried out as follows; when < -30dB: no risk level; the power distribution box of the cabin can normally work with the load equipment, and generally no electromagnetic interference occurs; In the range of -30dB to -6dB: low risk level; the electromagnetic interference risk on the ship is controllable; In the range of -6dB to 0dB: medium risk level; there is a transient peak electromagnetic interference risk hidden danger on the ship; >0dB interval: high risk level; potential or existing electromagnetic interference on the ship.

[0045] Beneficial effects:

[0046] 1) The ship power grid transient electromagnetic interference classification evaluation method provided by the present application realizes scientific classification and evaluation of the ship power grid transient peak interference by real-time online detection and comprehensive analysis of the anti-interference ability, sensitive threshold of the load equipment behind the cabin power distribution box of the ship, and the real-time online detection and comprehensive analysis of the ship power grid transient peak interference. Through the ship power grid transient peak interference classification evaluation and different risk levels, the influence degree of the ship power grid transient peak interference on the equipment can be directly reflected, which provides a decision basis for the safe operation of the ship and the maintenance and management of the power system, and ensures the safe operation of the ship.

[0047] 2) The ship power grid transient electromagnetic interference grading evaluation method provided by the application comprehensively considers the anti-interference ability, sensitive threshold and importance of different load devices in the ship power grid, obtains the weighted average sensitive threshold of the load devices in the cabin distribution box area of the power grid through a scientific calculation method, so that the evaluation result can better reflect the tolerance of the load devices on the ship to the transient interference in the power grid, and the evaluation result is more comprehensive and accurate compared with single index detection.

[0048] 3) The ship power grid transient electromagnetic interference grading evaluation method provided by the application realizes grading evaluation of the transient peak interference of the ship power grid through determination of the transient peak interference signal of the power grid and comparison with the average sensitivity, can intuitively provide the risk degree information of the transient peak interference of the power grid for the ship operator, and is convenient for timely taking targeted protection and optimization measures to ensure stable operation of the ship power grid and safety of the equipment.

[0049] 4) The evaluation method involved in the application has strong practicability and operability, is suitable for transient peak evaluation of ship power grids of different types and scales, and is helpful to improve the reliability and intelligent management level of the ship power grid system.

[0050] 5) The ship power grid transient electromagnetic interference grading evaluation system provided by the application can be used to execute the above-mentioned ship power grid transient peak interference grading evaluation method, the functions in the evaluation method are realized in a module mode, the anti-interference ability, sensitive threshold of the load devices behind the cabin distribution box of the ship and real-time online detection and comprehensive analysis of the transient peak interference of the ship power grid are detected by each module, scientific grading evaluation of the transient peak interference of the ship power grid is realized, the influence degree of the transient peak interference of the ship power grid on the equipment can be intuitively reflected through grading evaluation of the transient peak interference of the ship power grid and different risk levels, decision basis for safe operation of the ship and maintenance and management of the power system is provided, and safe operation of the ship is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1 A ship power grid transient electromagnetic interference grading evaluation method flowchart is provided for the embodiment 1 of the application.

[0052] Figure 2 A peak signal conduction sensitivity test configuration diagram is provided for the embodiment 1 of the application.

[0053] Figure 3 A peak signal conduction sensitivity injection transient peak signal is provided for the embodiment 1 of the application.

[0054] Figure 4 A power grid transient peak conduction emission test configuration diagram is provided for the embodiment 1 of the application.

[0055] Figure 5A ship power grid transient electromagnetic interference grading evaluation system composition block diagram provided in embodiment 3 of the present application. DETAILED DESCRIPTION

[0056] The present application will be described in detail below with reference to the drawings and examples.

[0057] Embodiment 1:

[0058] The present embodiment provides a ship power grid transient electromagnetic interference grading evaluation method, as shown in the figure, the method comprises the following steps: Figure 1

[0059] Step one: measure the device transient peak sensitivity threshold through the load device peak signal conduction sensitivity test.

[0060] In the embodiment of the present application, according to the peak signal conduction sensitivity test (CS06) method in HJB34A-2007 "ship electromagnetic compatibility requirements", the co-network load device at the rear end of the cabin distribution box of the ship power grid is subjected to different intensity simulated transient peak interference signals one by one, the interference signal threshold level and other parameters when each device appears abnormal performance or failure are recorded, the sensitivity threshold of the device is determined, and the sensitivity threshold can reflect the sensitivity degree of the device when subjected to transient peak interference of different intensity.

[0061] The peak signal conduction sensitivity test configuration diagram is as shown in the figure. Figure 2 .

[0062] In the present embodiment, the injected transient peak signal is as shown in the figure. Figure 3 The transient peak signal pulse width is 10us±20%. The transient peak signal amplitude V P The amplitude test is increased in turn according to 400V, 450V, 500V, 550V, 600V, 650V, 700V, 750V, 800V, 850V, 900V. The transient peak signal injection time of each amplitude is not less than 10min, and the phase of the transient peak signal is adjusted at the same time. When the abnormal performance or failure appears, the interference signal threshold level, i.e. the sensitivity threshold of the device, is recorded. The devices that do not appear electromagnetic interference phenomenon in the test process, the sensitivity threshold is recorded as the maximum value 900V.

[0063] Step two: classify the devices according to the importance degree, i.e. the degree of harm or consequence that the devices may cause to the ship platform after the transient peak electromagnetic interference appears.

[0064] The transient peak sensitivity threshold of each device measured in step one does not mean that the device will definitely appear electromagnetic interference phenomenon after being installed on the ship when subjected to the transient peak signal reaching or close to the sensitivity threshold, but only means that the probability of appearing electromagnetic interference is relatively high; on the contrary, the smaller the transient peak interference signal is than the sensitivity threshold, the lower the probability of appearing electromagnetic interference is.​

[0065] Different devices are assigned with importance coefficients, which reflect their importance degree, i.e. the degree of possible consequences or harm caused to the ship platform after the occurrence of transient spike electromagnetic interference. For devices with higher importance, such as the following category I devices, smaller importance coefficients are set, and the average sensitivity calculated after weighting assignment is reduced by using the importance coefficients as weights.

[0066] In this embodiment, the importance coefficient assignment range is set to 1-10, and the higher the importance degree, the smaller the assignment.

[0067] Category I devices: the highest importance devices on the ship. After being subjected to transient spike electromagnetic interference, they may cause physical damage to the subsystems or devices, and even affect the performance and safety of the entire ship. The importance coefficient w i The assignment range is set to 1-3.

[0068] Category II devices: higher importance devices on the ship. After being subjected to transient spike electromagnetic interference, they may cause the working performance of the subsystems or devices to decrease or malfunction, and they only make the system unable to complete part of the functions without affecting the system and personnel safety. The importance coefficient w i The assignment range is set to 4-6.

[0069] Category III devices: general importance devices on the ship. After being subjected to transient spike electromagnetic interference, the subsystems and devices of this category only have reduced working performance without malfunction; or even if malfunction is caused, the working state can be quickly restored by the crew without causing the system devices to lose functions. The importance coefficient w i The assignment range can be set to 7-10.

[0070] In this embodiment, the transient spike sensitivity threshold of each device obtained in step one and the importance degree assignment are combined, and the weighted average method is used to calculate the weighted average sensitivity threshold of the load devices at the back end of the distribution box, specifically:

[0071] The calculated weighted average sensitivity threshold of the main load devices at the back end of the distribution box is :

[0072]

[0073] Wherein, S i is the sensitivity threshold of the i-th load device, and w i is the importance coefficient of the i-th load device.

[0074] Step three: at the output end of the cabin distribution box of the ship power grid, a transient spike conducted emission detection device is applied to monitor and collect the transient spike conducted emission data of the power grid in real time.

[0075] The grid transient spike conduction emission test configuration diagram is as shown in FIG. 1 Figure 4 .

[0076] The monitoring and collecting time should not be less than 1 sea voyage of the ship. During the monitoring and collecting process, the low-frequency emission equipment such as sonar on the ship should emit at full power for not less than 2 times; the radio frequency emission equipment such as short-wave communication equipment and satellite communication equipment respectively emits at rated power for not less than 2 times (the emission frequency is taken as 2 high and low frequency points in the respective working frequency band); the microwave emission equipment such as radar should emit at full power for not less than 2 times; the high-power equipment such as high-pressure air compressor, bilge pump, full-ship hydraulic pump and propeller respectively starts, works, stops or switches the running state for not less than 2 times.

[0077] For the transient spike interference signals collected in the monitoring and collecting process, according to the strength, pulse width, occurrence frequency and other parameters of the obtained transient spike interference signals, the peak value detection and statistical analysis method is adopted to extract the maximum value from the time-varying signal sequence, and the grid transient spike interference peak value V PEAK .

[0078] The grid transient spike interference measured value is:

[0079] .

[0080] Step four: grading evaluation of the ship grid transient spike interference.

[0081] The difference value between the grid transient spike interference measured value dBV and the weighted average sensitive threshold value is calculated. = dBV- According to the difference value, the grading evaluation of the ship grid transient spike interference is carried out as follows: when < -30dB: no risk level; the power distribution box of the cabin of the grid can normally work in compatibility, and generally no electromagnetic interference occurs. In the interval of -30dB to -6dB: low risk level; the electromagnetic interference risk on the ship is controllable, and the sensitive threshold value of each equipment and the grid transient spike test result should be closely observed. In the interval of -6dB to 0dB: medium risk level; there may be transient spike electromagnetic interference risk hidden danger on the ship, and the electromagnetic interference protection measures should be actively reserved to reduce the electromagnetic interference risk. >0dB: high risk level; the potential or existing electromagnetic interference on the ship needs to check and rectify the weak links of electromagnetic compatibility and take effective electromagnetic interference protection control measures to reduce the transient spike interference evaluation.

[0082] Through the grading evaluation of the ship power grid transient spike interference and different risk levels, the influence degree of the ship power grid transient spike interference on the equipment can be directly reflected, and a decision basis for the safe operation of the ship and the maintenance and management of the power system is provided.

[0083] Embodiment 2

[0084] In this embodiment, a ship power grid transient electromagnetic interference grading evaluation method is realized through the following steps:

[0085] Step 1: In a voyage of the ship, the transient spike interference sensitivity test is performed on n load equipment at the rear end of the distribution box of the bridge, and the transient spike sensitivity threshold of the equipment is determined. Using a dedicated electromagnetic compatibility test instrument, the transient spike interference signal with an increasing amplitude of 400V-900V and a pulse width of 10us is applied to each equipment according to the relevant standards, the threshold level parameters of the interference signal when each equipment appears abnormal conditions such as performance decline and malfunction are recorded, and the sensitive threshold of the equipment is determined. For example, when the transient spike interference signal with an intensity of 500V and a pulse width of 10us is injected into the sonar equipment, the sonar display line spectrum appears black screen flicker, and the sonar sensitive threshold S1=500V. When the transient spike interference signal with an intensity of 600V and a pulse width of 10us is injected into the electronic chart system, the electronic chart system appears display garbled code, and the sensitive threshold S2=600V. When the transient spike interference signal with an intensity of 350V and a pulse width of 10us is injected into the lighting device, the lighting device appears obvious brightness change, and the sensitive threshold S3=350V. When the transient spike interference signal with a pulse width of 10us is injected into the steering device with an intensity of 900V, no sensitive phenomenon occurs, and the sensitive threshold is S4=900V.

[0086] Step 2: According to the functions and importance of each equipment in the operation of the ship, the importance coefficient of the n equipment in the bridge is valued. The importance coefficient of the sonar is valued as w1=2, the importance coefficient of the electronic chart system is valued as w2=6, the importance coefficient of the lighting device is valued as w3=10, and the importance coefficient of the steering device is valued as w4=1.

[0087] The weighted average sensitive threshold of the main load equipment at the rear end of the distribution box of the bridge is calculated, as shown in Table 1.

[0088] Table 1

[0089]

[0090] Step 3: In the sea voyage, a high-precision transient spike interference signal detection device is installed at the output end of the distribution box of the bridge, and the device is continuously operated for 120 hours. The transient spike interference signal is collected, and the signal is processed by frequency spectrum analysis and intensity calculation. The peak value V PEAK =100V of the power grid transient spike interference is calculated.

[0091] Grid transient spike interference measured value = 40dB.

[0092] Step 4: compare the grid transient spike interference measured value with the weighted average sensitive threshold value , calculate the difference Δ = 40 - 13.5 = 26.5dBV. = -13.5. According to the grading rules, it is determined that the cabin room grid transient spike interference is at low risk level, and the ship electromagnetic interference risk is controllable. The sensitive threshold value of each equipment and the grid transient spike test result can be closely monitored during navigation.

[0093] Example 3:

[0094] In order to realize the ship grid transient electromagnetic interference grading evaluation method as described in the embodiment, the embodiment also provides a ship grid transient electromagnetic interference grading evaluation system, which is composed of the following modules as shown in Figure 5 .

[0095] The sensitive threshold value measuring module is used to apply different intensity simulated transient spike interference signals to the common network load equipment at the rear end of the cabin room distribution box of the ship grid one by one by using the spike signal conduction sensitivity test, and the transient spike sensitive threshold value of the equipment is measured. In the embodiment, the sensitive threshold value measuring module specifically performs the following steps:

[0096] The transient spike signal is injected into the common network load equipment at the rear end of the cabin room distribution box of the ship grid, the transient spike signal pulse width is 10us±20%, the transient spike signal amplitude V P The amplitude test is performed in sequence according to 400V, 450V, 500V, 550V, 600V, 650V, 700V, 750V, 800V, 850V and 900V. The transient spike signal injection time of each amplitude is not less than 10min. At the same time, the phase of the transient spike signal is adjusted. When performance abnormalities or failures occur, the interference signal threshold level, i.e. the sensitive threshold value of the equipment, is recorded. During the test, the equipment that does not appear electromagnetic interference phenomenon is recorded with the maximum value 900V as the sensitive threshold value.

[0097] The weighted average sensitive threshold value calculating module is used to classify the equipment according to the importance degree of the equipment and assign importance coefficients. Combined with the transient spike sensitive threshold values of each equipment obtained in step one and the importance coefficient assignment, the weighted average sensitive threshold value of the load equipment at the rear end of the distribution box is calculated by using the weighted average method. In the embodiment, in the weighted average sensitive threshold value calculating module, the equipment is classified according to the importance degree of the equipment and the importance coefficients are assigned, which are specifically as follows:

[0098] The equipment is classified into class I equipment, class II equipment and class III equipment according to the importance degree of the equipment.

[0099] The importance coefficient assignment range is set to 1-10;

[0100] Class I equipment is the highest important equipment class on the ship. After the class I equipment is subjected to transient peak electromagnetic interference, physical damage of the subsystem or equipment is caused, and the performance and safety of the entire ship are affected. The importance coefficient w of the class I equipment is set to 1. i The assignment range is set to 1-3.

[0101] Class II equipment refers to the equipment that, after being subjected to transient peak electromagnetic interference, causes the working performance of the subsystem or equipment to be reduced or a fault to occur, only makes the system unable to complete part of the functions, and does not affect the system and personnel safety. The importance coefficient w of the class II equipment is set to 4-6. i The assignment range is set to 4-6.

[0102] Class III equipment refers to the equipment that, after being subjected to transient peak electromagnetic interference, only causes the working performance of the subsystem and equipment to be reduced, does not cause a fault, or even causes a fault, but after maintenance, the working state is restored within a certain time, and does not cause the system equipment to lose the functions. The importance coefficient w of the class III equipment is set to 7-10. i The assignment range is set to 7-10.

[0103] The calculated weighted average sensitive threshold of the main load equipment at the back end of the distribution box is :

[0104]

[0105] wherein, S i is the sensitive threshold of the i-th load equipment, and w i is the importance coefficient of the i-th load equipment.

[0106] The grid transient peak interference measurement value identification module is used for real-time monitoring and collecting grid transient peak conducted emission data at the output end of the cabin distribution box of the ship power grid by using a transient peak conducted emission detection device, and identifying the grid transient peak interference measurement value from the data.

[0107] In this embodiment, the time for monitoring and collecting the emission data is not less than one sea voyage of the ship;

[0108] During the monitoring and collecting process, the low-frequency emission equipment such as sonar on the ship should be full-power emission not less than 2 times; the radio frequency emission equipment should be respectively emitted at the rated power not less than 2 times, and the emission frequency is taken as 2 frequency points in the respective working frequency band;

[0109] The microwave emission equipment should be full-power emission not less than 2 times;

[0110] Power more than the set value of high-power equipment, respectively, start, work, stop (or operating state switching) no less than 2 times; high-power equipment includes high-pressure air compressor, bilge pump, ship hydraulic pump, propeller;

[0111] The transient peak interference signal collected by monitoring is analyzed according to the parameters including intensity, pulse width and occurrence frequency of the transient peak interference signal, the maximum value is extracted from the time-varying signal sequence by using peak detection and statistical analysis method, and the power grid transient peak interference peak value V PEAK is identified according to the spectrum characteristics and energy distribution of the transient peak signal.

[0112] The measured value of the power grid transient peak interference is:

[0113] .

[0114] The evaluation module is used to compare the measured value of the power grid transient peak interference with the weighted average sensitive threshold, calculate the difference value, and carry out the classification evaluation of the ship power grid transient peak interference according to the difference value. In this embodiment, the evaluation module is specifically:

[0115] The measured value of the power grid transient peak interference dBV is compared with the weighted average sensitive threshold , the difference value =dBV- is calculated, and the classification evaluation of the ship power grid transient peak interference is carried out according to the difference value. When < -30dB: no risk level; the power distribution box of the cabin can normally work with the load equipment, and no electromagnetic interference generally occurs. When in the interval of -30dB to -6dB: low risk level; the electromagnetic interference risk on the ship is controllable. When in the interval of -6dB to 0dB: medium risk level; there is a risk of transient peak electromagnetic interference on the ship. When in the interval of >0dB: high risk level; there is potential or existing electromagnetic interference on the ship.

[0116] The ship power grid transient electromagnetic interference classification evaluation system provided in this embodiment can be realized by data processing programs, and can also be realized by hardware, such as logic gates, switches, application specific integrated circuits (ASIC), programmable logic controllers and embedded microcontrollers. Therefore, the hardware that can realize the method of the application can also constitute the application.

[0117] The computer program product of the present application can be a computer program embodied on a non-transitory computer readable medium. Such non-transitory computer readable medium can include, but is not limited to, floppy diskettes, CD-ROMs, DVDs, flash memories, memory sticks, and hard drives. The computer program product can also include code segments that when executed on a processor, carry out the methods disclosed herein.

[0118] To sum up, the above is only the preferred embodiment of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for grading assessment of shipboard power system transient electromagnetic interference, characterized in that, The method comprises the following steps: Step 1: using a spike signal conduction sensitivity test, applying different intensity of simulated transient spike interference signals to the common network load equipment at the rear end of the cabin distribution box of the ship power grid one by one, and measuring the transient spike sensitivity threshold of the equipment; Step 2: according to the importance of the equipment, the equipment is classified and the importance coefficient is assigned; Combined with the transient spike sensitivity threshold and the importance coefficient assignment of each equipment, the weighted average sensitivity threshold of the load equipment at the rear end of the distribution box is calculated by using the weighted average method with the importance coefficient as the weight; Step 3: at the output end of the cabin distribution box of the ship power grid, the transient spike conduction emission detection device is used to monitor and collect the transient spike conduction emission data of the power grid in real time, and the transient spike interference measurement value is identified therefrom; Step 4: comparing the transient spike interference measurement value of the power grid with the weighted average sensitivity threshold, calculating the difference value; according to the difference value, the transient spike interference grading evaluation of the ship power grid is carried out.

2. The method of claim 1, wherein, In the step 1, specifically: For the common network load equipment behind the cabin distribution box of the ship power grid, a transient spike signal is injected, the pulse width of the transient spike signal is 10us±20%, the amplitude of the transient spike signal is V P The amplitude is tested in sequence by increasing 400V, 450V, 500V, 550V, 600V, 650V, 700V, 750V, 800V, 850V, 900V, and each amplitude transient spike signal injection time is not less than 10min, while adjusting the phase of the transient spike signal, when performance abnormalities or failures occur, record the interference signal threshold level, that is, the sensitive threshold of the equipment; The sensitive threshold of the equipment that does not appear electromagnetic interference phenomenon in the test process is recorded as the maximum value 900V.

3. The method of claim 1, wherein, In the step 2, according to the importance of the equipment, the equipment is classified and the importance coefficient is assigned, specifically: The equipment is divided into class I equipment to class III equipment according to its importance; The importance coefficient assignment range is set to 1-10; The class I equipment is the highest important equipment class on the ship, and the class I equipment causes physical damage to the subsystem or equipment after being subjected to transient spike electromagnetic interference, affecting the performance and safety of the whole ship; Setting the importance coefficient w of the class I device i Assigning the range of 1-3; The class II equipment refers to: after being subjected to transient peak electromagnetic interference, resulting in subsystem or equipment performance reduction or failure, only the system can not complete some functions, but does not affect the system and personnel safety; the importance coefficient w of class II equipment i The assignment range is set to 4-6; The class III equipment refers to: after being subjected to transient peak electromagnetic interference, the class of subsystems and equipment only has reduced working performance, without failure; or even if failure is caused, the working state is restored after maintenance within a certain time, without causing the system equipment to lose function; the importance coefficient w of the class III equipment i The assignment range is set to 7-10.

4. The method of claim 1, wherein, The step 2, the calculated power distribution box back-end main load device of weighted average sensitive threshold is : ； wherein S i is a sensitivity threshold of the i-th load device, w i is an importance coefficient of the i-th load device.

5. The method of claim 1, wherein, In the step 3, at the output end of the cabin distribution box of the ship power grid, the transient spike conduction emission detection device is used to monitor and collect the transient spike conduction emission data of the power grid in real time, and the monitoring and collecting process is specifically: The time for monitoring and collecting emission data is not less than one sea voyage of the ship; During the monitoring and collecting process, the low-frequency emission equipment on the ship should emit at full power for not less than 2 times, and the low-frequency emission equipment includes sonar; the radio frequency emission equipment respectively emits at rated power for not less than 2 times, and the emission frequency is taken at 2 frequency points within the respective working frequency band; The microwave emission equipment emits at full power for not less than 2 times; The high-power equipment with power exceeding the set value respectively starts, works, stops or switches the running state for not less than 2 times; the high-power equipment includes high-pressure air compressor, cabin bottom pump, whole-ship hydraulic pump and propeller.

6. The method for grading assessment of transient electromagnetic interference of a ship power system according to claim 1 or 5, characterized in that, In the step 3, for monitoring and collecting the transient spike conduction emission data of the power grid, the transient spike interference measurement value of the power grid is identified, and the specific way is: For the transient peak interference signal collected by monitoring, according to the parameters including intensity, pulse width, occurrence frequency of the obtained transient peak interference signal, the maximum value is extracted from the time-varying signal sequence by using the peak detection and statistical analysis method, and the power grid transient peak interference peak value V PEAK is identified combined with the frequency spectrum characteristics and energy distribution of the transient peak signal. Then the transient spike interference measurement value of the power grid is: 。 7. The method of claim 1, wherein, In the step 4: comparing the transient spike interference measurement value of the power grid with the weighted average sensitivity threshold, calculating the difference value; according to the difference value, the transient spike interference grading evaluation of the ship power grid is carried out, specifically: Comparing the measured value of the power grid transient spike interference dBV with the weighted average sensitivity threshold value , calculating the difference between the two = dBV- , according to the difference result, the classification evaluation of the ship power grid transient spike interference is carried out as follows; When -30dB: no risk level; the load devices of the power distribution box in the power grid cabin can work normally and generally no electromagnetic interference occurs; In the interval of -30dB~ -6dB: low risk level; the electromagnetic interference risk on the ship is controllable; When in the interval of -6dB~0dB: medium risk level; There is a transient spike electromagnetic interference risk hidden danger on the ship; >0 dB interval: high risk level; potential or existing electromagnetic interference on board the ship.

8. A shipboard power system transient electromagnetic interference hierarchical assessment system, characterized by, The method comprises the following modules: The sensitive threshold determination module is used for applying different intensity analog transient peak interference signals to the common network load equipment at the rear end of the cabin distribution box of the ship power grid one by one by using a peak signal conduction sensitivity test to determine the transient peak sensitive threshold of the equipment; specifically: for the common network load equipment at the rear end of the cabin distribution box of the ship power grid, a transient peak signal is injected, the pulse width of the transient peak signal is 10us±20%, the amplitude of the transient peak signal is V P The amplitude test is sequentially increased by 400V, 450V, 500V, 550V, 600V, 650V, 700V, 750V, 800V, 850V, 900V, and each amplitude transient peak signal injection time is not less than 10min, while adjusting the phase of the transient peak signal, when performance abnormalities or failures occur, record the interference signal threshold level, that is, the sensitive threshold of the equipment; The sensitive threshold of the equipment that does not appear electromagnetic interference phenomenon in the test process is recorded as the maximum value 900V. The weighted average sensitive threshold calculation module is configured to classify the devices according to the importance degrees of the devices and assign importance coefficients to the devices; the transient peak sensitive threshold of each device obtained by the sensitive threshold determination module and the importance coefficient assignment are combined, the importance coefficient is used as a weight, and a weighted average method is used to calculate the weighted average sensitive threshold of the load devices at the rear end of the distribution box, specifically as follows: ； wherein, S is the computed weighted average sensitivity threshold of the main load devices of the electrical distribution cabinet backend, i S i is the sensitivity threshold of the i th load device, i w i is the importance coefficient of the i th load device; the devices are classified into class I devices, class II devices and class III devices according to their importance. The importance coefficient assignment range is set to 1-10. The class I equipment is the most important equipment on the ship, and the class I equipment is physically damaged after being disturbed by the transient peak electromagnetic interference, which affects the performance and safety of the whole ship; the importance coefficient w of the class I equipment is set i The value range is 1-3; The class II equipment refers to: after being subjected to transient peak electromagnetic interference, resulting in subsystem or equipment performance reduction or failure, only the system can not complete some functions, but does not affect the system and personnel safety; the importance coefficient w of class II equipment i The assignment range is set to 4-6; The class III equipment refers to: after being subjected to transient peak electromagnetic interference, the class of subsystems and equipment only has reduced working performance, without failure; or even if failure is caused, the working state is restored after maintenance within a certain time, without causing the system equipment to lose function; the importance coefficient w of the class III equipment i The assignment range is set to 7-10; The power grid transient peak interference measurement value identification module is configured to apply a transient peak conduction emission detection device to monitor and collect power grid transient peak conduction emission data in real time at the output end of the cabin distribution box of the ship power grid, and identify the power grid transient peak interference measurement value from the data. The evaluation module is configured to compare the power grid transient peak interference measurement value with the weighted average sensitive threshold, calculate the difference between the two, and perform classification and evaluation of the ship power grid transient peak interference according to the difference result.

9. A shipboard power system transient electromagnetic interference hierarchical assessment system as claimed in claim 8, wherein, In the power grid transient peak interference measurement value identification module, a transient peak conduction emission detection device is applied to monitor and collect power grid transient peak conduction emission data in real time at the output end of the cabin distribution box of the ship power grid, and the monitoring and collection process is specifically as follows: The monitoring and collection process lasts for no less than one sea voyage of the ship; During the monitoring and collection process, the low-frequency emission devices on the ship should emit at full power for no less than 2 times, including sonar; the radio frequency emission devices should emit at rated power for no less than 2 times, with 2 frequency points in their respective working frequency bands; The microwave emission devices should emit at full power for no less than 2 times; The high-power devices with power exceeding the set value should switch between start, work, stop, or run states for no less than 2 times, including high-pressure air compressors, cabin bottom pumps, ship hydraulic pumps, and propellers; In the power grid transient peak interference measurement value identification module, the power grid transient peak interference measurement value is identified from the monitored and collected power grid transient peak conduction emission data, and the specific method is as follows: For the transient peak interference signal collected by monitoring, according to the parameters including intensity, pulse width, occurrence frequency of the acquired transient peak interference signal, the maximum value is extracted from the time-varying signal sequence by using the peak detection and statistical analysis method, and the power spectrum characteristics and energy distribution of the transient peak signal are combined to identify the power grid transient peak interference peak V PEAK ; The power grid transient peak interference measurement value is as follows: 。 10. A shipboard power system transient electromagnetic interference hierarchical assessment system as claimed in claim 8, wherein, The evaluation module is specifically as follows: Comparing the measured value of the power grid transient spike interference dBV with the weighted average sensitivity threshold , calculating the difference between the two = dBV- , according to the difference result, the classification evaluation of the ship power grid transient spike interference is carried out as follows; -30dB: no risk level; the power distribution box of the power grid cabin can normally work with the load equipment, and no electromagnetic interference occurs in general; When in the interval of -30dB~ -6dB: low risk level; the electromagnetic interference risk on the ship is controllable; In the interval of -6dB~0dB: medium risk level; there is a risk of transient peak electromagnetic interference on the ship; In the interval of >0dB: high risk level; there is potential or existing electromagnetic interference on the ship.

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