Signal acquisition method and device, equipment and storage medium

Abstract

The embodiment of the invention provides a signal acquisition method, device and equipment and a storage medium, relates to the field of reciprocating machines, and is used for acquiring a full-period signal of a reciprocating machine which comprises a first air cylinder. The method comprises the steps that first envelope energy of multiple impacts of the reciprocating machine is determined based on an envelope curve of a first vibration signal of a cylinder cover of a first air cylinder in an angular domain in a double-cycle mode and a first standard valve timing table of the reciprocating machine; determining a second envelope energy for the plurality of impacts based on the envelope curve and a second valve timing meter lagging a target angle relative to the first valve timing meter; based on the magnitude relation between the first total energy and the second total energy, the occurrence condition of the phase shifting phenomenon is determined, the first total energy is the sum of the first envelope energy, and the second total energy is the sum of the second envelope energy; and intercepting a single-cycle second vibration signal from the first vibration signal based on the occurrence condition. Therefore, the accurate cylinder cover angular domain full-period signal can be obtained.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of reciprocating mechanical technology, and in particular to signal acquisition methods, devices, equipment, and storage media. Background Art

[0002] Marine propulsion systems include reciprocating machinery, including but not limited to diesel engines. For example, during operation, diesel engines, including their components and the entire engine, are subject to a combination of excitations, including the inertial forces of reciprocating components, fluctuations in combustion pressure, torque variations, torsional vibrations, and centrifugal forces caused by imbalances in rotating components. These harsh operating environments are highly susceptible to failure.

[0003] Current condition-based maintenance (CBM) for diesel engines primarily focuses on parameters such as vibration and speed. The cylinder head vibration signal contains a wealth of useful information, reflecting the operating conditions of the moving components within the cylinder. Using the key phase signal as a reference point, the vibration signal can be resampled over the entire cycle, achieving a precise match between the signal and the actual position of the piston within the cylinder. This allows for the acquisition of key information such as in-cylinder ignition and valve opening and closing based on the angular domain. Because the key phase sensor generates a key phase signal for each complete crankshaft rotation of a diesel engine, and two crankshaft rotations constitute a working cycle, phase shifts may occur when capturing the key phase signal over the entire cycle. This can lead to inconsistencies in the primary impact phase of the captured cylinder head angular domain full cycle signal, thus affecting subsequent feature extraction and fault diagnosis. Summary of the Invention

[0004] The embodiments of the present application provide a signal acquisition method, apparatus, device, and storage medium, which can acquire accurate cylinder head angular domain full-cycle signals.

[0005] In a first aspect, an embodiment of the present application provides a signal acquisition method for acquiring a full-cycle signal of a reciprocating machine, the reciprocating machine including a first cylinder, the method comprising:

[0006] Determining first envelope energies of respective multiple impacts of the reciprocating machine based on an envelope curve of a first vibration signal of a cylinder head of the first cylinder in a double period in an angular domain and a first valve timing table of a standard for the reciprocating machine;

[0007] Determining a second envelope energy of each of the plurality of impacts based on the envelope curve and the second valve timing table; wherein the second valve timing table lags behind the first valve timing table by a target angle;

[0008] Determining the occurrence of the phase shift phenomenon based on the magnitude relationship between the first total energy and the second total energy; wherein the first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies;

[0009] Based on the occurrence of the phase-out phenomenon, a single-cycle second vibration signal is intercepted from the first vibration signal.

[0010] In one embodiment, the reciprocating machine further comprises a flywheel, a vibration acceleration sensor is mounted on the cylinder head of the first cylinder, a key phase sensor and a key phase block are mounted on the flywheel, and a position of the key phase block is aligned with the ignition top dead center of the first cylinder;

[0011] The above method further includes:

[0012] Based on the key phase signal generated by the key phase sensor, a double-period third vibration signal is intercepted from the vibration signal collected by the vibration acceleration sensor;

[0013] The third vibration signal is converted into a first vibration signal in the angular domain.

[0014] In one embodiment, the above method further comprises:

[0015] An envelope curve is determined based on the absolute value of the first vibration signal using a Hilbert transform.

[0016] In one embodiment, determining first envelope energies of respective multiple impacts of a reciprocating machine based on an envelope curve of a first vibration signal of a cylinder head of a first cylinder in a double cycle in an angular domain and a first valve timing table of a standard for the reciprocating machine includes:

[0017] For each target impact among the above-mentioned multiple impacts, a trapezoidal integration method is used to determine a first area of ​​a first target interval under the envelope curve, and the first area is used as a first envelope energy of the target impact; wherein, the starting point and end point of the first target interval are determined based on the angle values ​​of events related to the target impact in the first valve timing table.

[0018] In one embodiment, determining the second envelope energy of each of the plurality of impacts based on the envelope curve and the second valve timing table includes:

[0019] For each target impact among the above-mentioned multiple impacts, a trapezoidal integration method is used to determine a second area of ​​a second target interval under the envelope curve, and the second area is used as the second envelope energy of the target impact; wherein the start and end points of the second target interval are determined based on the angle values ​​of events related to the target impact in the second valve timing table.

[0020] In one embodiment, determining the occurrence of the phase shift phenomenon based on the magnitude relationship between the first total energy and the second total energy includes:

[0021] In response to the first total energy being greater than or equal to the second total energy, it is determined that no out-of-phase phenomenon occurs.

[0022] In one embodiment, determining the occurrence of the phase shift phenomenon based on the magnitude relationship between the first total energy and the second total energy includes:

[0023] In response to the first total energy being less than the second total energy, it is determined that an out-of-phase phenomenon occurs.

[0024] In one embodiment, the starting angle of the second vibration signal is 0° when the phase shift phenomenon does not occur, and is the target angle when the phase shift phenomenon occurs.

[0025] In one embodiment, the reciprocating machine is a diesel engine.

[0026] In one embodiment, the plurality of impacts include an ignition impact, the ignition top dead center in the first valve timing table is 360°, and the target angle is 360°.

[0027] In one embodiment, the reciprocating machine further comprises at least one second cylinder, the first cylinder being configured as a reference cylinder;

[0028] After extracting a single-cycle second vibration signal from the first vibration signal, the method further includes:

[0029] Based on the relationship between the ignition sequence and ignition interval of each second cylinder and the first cylinder, a single-cycle fifth vibration signal is intercepted from the double-cycle fourth vibration signal of the cylinder head of each second cylinder in the angular domain.

[0030] In one embodiment, the above method further comprises:

[0031] For the target vibration signal having a starting angle greater than 0° in the second vibration signal and each of the fifth vibration signals, the angle range of the target vibration signal is adjusted to a range from 0° to 720°.

[0032] In a second aspect, an embodiment of the present application provides a signal acquisition device for acquiring a full-cycle signal of a reciprocating machine, the reciprocating machine including a first cylinder, the device comprising:

[0033] a first determining module configured to determine first envelope energies of respective multiple impacts of the reciprocating machine based on an envelope curve of a first vibration signal of a cylinder head of the first cylinder in a double period in an angular domain and a first valve timing table of a reciprocating machine standard;

[0034] a second determining module configured to determine a second envelope energy of each of the plurality of impacts based on the envelope curve and a second valve timing table, wherein the second valve timing table lags behind the first valve timing table by a target angle;

[0035] a third determining module configured to determine the occurrence of the phase shift phenomenon based on a magnitude relationship between the first total energy and the second total energy; wherein the first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies;

[0036] The interception module is configured to intercept a single-cycle second vibration signal from the first vibration signal based on the occurrence of the phase deviation phenomenon.

[0037] In a third aspect, an embodiment of the present application provides a computer device comprising a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the signal acquisition method described in any implementation method in the first aspect is implemented.

[0038] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the signal acquisition method described in any implementation manner in the first aspect is implemented.

[0039] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the signal acquisition method described in any implementation method in the first aspect.

[0040] The solution provided in an embodiment of the present application involves a reciprocating machine including a first cylinder. In this solution, the first envelope energy of each of multiple impacts of the reciprocating machine can be determined based on the envelope curve of a double-cycle first vibration signal of the cylinder head of the first cylinder in the angular domain and a first standard valve timing table for reciprocating machines. The second envelope energy of each of the multiple impacts can also be determined based on this envelope curve and a second valve timing table. The second valve timing table lags the first valve timing table by a target angle. The occurrence of a phase shift phenomenon can then be determined based on the relationship between the first total energy and the second total energy. Based on the occurrence of the phase shift phenomenon, a single-cycle second vibration signal can be extracted from the first vibration signal. The first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies. This solution uses the double-cycle first vibration signal of the cylinder head of the first cylinder in the angular domain to determine phase shift based on the combined impacts, and extracts a single-cycle second vibration signal from the first vibration signal based on the occurrence of the phase shift phenomenon. This allows accurate full-cycle signals of the cylinder head in the angular domain to be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The following detailed description of the specific embodiments of the present application in conjunction with the accompanying drawings will make the technical solutions and other beneficial effects of the present application apparent.

[0042] Figure 1 is a flow chart of the signal acquisition method provided in an embodiment of the present application;

[0043] Figure 2 is another flow chart of the signal acquisition method provided in an embodiment of the present application;

[0044] Figure 3 1 is an exemplary schematic diagram of a key phase signal and a double-period vibration signal of the cylinder heads of all cylinders in the angular domain in an embodiment of the present application;

[0045] Figure 4 is an exemplary schematic diagram of the standard single-cycle signals of all cylinders in the embodiment of the present application;

[0046] Figure 5 It is a structural diagram of the signal acquisition device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0048] In the description of this application, it should be noted that, unless otherwise specified or limited, the term "and / or" herein is merely a description of an association relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. Furthermore, the character " / " herein, unless otherwise specified, generally indicates that the associated objects are in an "or" relationship.

[0049] As mentioned above, current condition-based diesel engine maintenance mainly focuses on parameters such as vibration and speed. The vibration signal of the cylinder head contains a lot of rich and useful information, which can reflect the working condition of the moving parts in the cylinder.

[0050] Using the key phase signal as a reference point, the vibration signal can be resampled over the entire cycle, achieving a precise match between the signal and the actual position of the piston within the cylinder. This allows key information such as in-cylinder ignition and valve opening and closing to be acquired based on the angular domain. Since the key phase sensor generates a key phase signal for each crankshaft rotation of a diesel engine, and two crankshaft rotations constitute a working cycle, phase shifts may occur when capturing the key phase signal over the entire cycle. This can lead to inconsistencies in the main impact phase of the captured cylinder head angular domain full cycle signal, thus affecting subsequent feature extraction and fault diagnosis.

[0051] One signal acquisition method primarily uses a crankshaft groove or an external key phase block as a trigger signal. Each crankshaft rotation (i.e., 360°) generates a key phase signal, and two rotations (i.e., 720°) constitute a complete signal cycle. An out-of-phase signal is the signal between the two closest ignition top dead center signals, while a non-out-of-phase signal is the signal between the two closest non-ignition top dead center signals. The signals captured by this method cannot distinguish whether out-of-phase has occurred, which is not conducive to subsequent angular domain-based feature extraction and fault diagnosis.

[0052] An embodiment of the present application provides a signal acquisition method, which can perform phase deviation judgment based on combined impact by using a double-cycle first vibration signal of the cylinder head of the first cylinder in the angular domain, and intercept a single-cycle second vibration signal from the first vibration signal based on the occurrence of the phase deviation phenomenon, thereby obtaining an accurate full-cycle signal of the cylinder head in the angular domain.

[0053] Figure 1 This is a flow chart of a signal acquisition method provided in an embodiment of the present application. The method is used to acquire a full-cycle signal of a reciprocating machine, the reciprocating machine including a first cylinder. In one example, the reciprocating machine may be an internal combustion engine. Furthermore, the internal combustion engine may include any of a diesel engine and a gasoline engine. The method comprises the following steps:

[0054] S101: Determine first envelope energies of multiple impacts of the reciprocating machine based on an envelope curve of a first vibration signal of a cylinder head of a first cylinder in a double period in an angular domain and a first valve timing table of a standard reciprocating machine;

[0055] S103: Determining a second envelope energy of each of the plurality of impacts based on the envelope curve and a second valve timing table, wherein the second valve timing table lags behind the first valve timing table by a target angle;

[0056] S105: Determine the occurrence of the phase shift phenomenon based on the magnitude relationship between the first total energy and the second total energy; wherein the first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies;

[0057] S107: Based on the occurrence of the phase shift phenomenon, a second vibration signal of a single cycle is intercepted from the first vibration signal.

[0058] exist Figure 1 In the solution provided by the corresponding embodiment, the first envelope energy of each of the multiple impacts of a reciprocating machine can be determined based on the envelope curve of the first vibration signal of the cylinder head of the first cylinder in the angular domain and the first standard valve timing table for reciprocating machines. The second envelope energy of each of the multiple impacts can also be determined based on the envelope curve and the second valve timing table. The second valve timing table lags the first valve timing table by a target angle. The occurrence of phase shifting can then be determined based on the relationship between the first total energy and the second total energy. Based on the occurrence of phase shifting, a single-cycle second vibration signal can be extracted from the first vibration signal. The first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies. This solution uses the first vibration signal of the cylinder head of the first cylinder in the angular domain to determine phase shifting based on the combined impacts, and extracts the single-cycle second vibration signal from the first vibration signal based on the occurrence of phase shifting. This allows accurate full-cycle signals of the cylinder head in the angular domain to be obtained.

[0059] Next, steps S101 to S107 will be described.

[0060] In step S101, the first envelope energy of each of the multiple impacts of the reciprocating machine can be determined based on the envelope curve of the first vibration signal of the cylinder head of the first cylinder in the double cycle in the angular domain and the first valve timing table of the reciprocating machine standard. It should be noted that the first vibration signal is a vibration signal of 0° to 1440°. A vibration acceleration sensor can be installed on the cylinder head of the first cylinder, and a key phase sensor and a key phase block can be installed on the flywheel of the reciprocating machine. The position of the key phase block is aligned with the top dead center (TDC) of the ignition of the first cylinder. The first vibration signal can be determined based on the key phase signal generated by the key phase sensor and the vibration signal collected by the vibration acceleration sensor.

[0061] A key phase sensor is a sensor used to detect the rotational position of an engine. By detecting specific markings on the flywheel (i.e., key phase blocks), the key phase sensor can provide precise position information to the Engine Control Unit (ECU), helping to determine the engine's operating cycle. Ignition top dead center typically refers to the point in the cylinder where the piston reaches its highest point. At this position, the piston is closest to the cylinder head. Ignition top dead center is a critical moment in the engine's operating cycle. Typically, this is the point where the fuel ignites (in diesel engines, through the high-temperature spontaneous combustion of compressed air), beginning combustion and generating power.

[0062] Furthermore, the method for acquiring the first vibration signal may include: based on the key phase signal generated by the key phase sensor, intercepting a double-period third vibration signal from the vibration signal collected by a vibration acceleration sensor mounted on the cylinder head of the first cylinder; and converting the third vibration signal into the first vibration signal in the angular domain. It should be understood that the third vibration signal is a vibration signal in the time domain.

[0063] As an implementation method, the third vibration signal can be converted into the first vibration signal in the angular domain using the following formula (1):

[0064]

[0065] Where N is the number of sampling points in a double period, n is the time domain index of the vibration signal, and a is the crankshaft angle value in the angular domain.

[0066] In one embodiment, the envelope curve of the first vibration signal can be determined based on the absolute value of the first vibration signal using a Hilbert transform. The Hilbert transform is a mathematical transformation widely used in signal processing to convert a real signal into its analytical signal. The analytical signal is a complex signal whose real part is the original signal and whose imaginary part is the Hilbert transform of the original signal. Determining the envelope curve of the first vibration signal using the Hilbert transform ensures more accurate extraction of the envelope curve.

[0067] The first valve timing table can be determined based on a valve timing diagram for a reciprocating machine. The first valve timing table can include angle values ​​for multiple events. These multiple events can include, for example, ignition top dead center, intake valve opening, intake valve closing, exhaust valve opening, and exhaust valve closing. Ignition top dead center can be 360 ​​degrees, and the angle values ​​for other events can be determined based on ignition top dead center and parameters in the valve timing diagram.

[0068] The plurality of shocks may include at least some shocks within a working cycle of the reciprocating machine. In one example, the plurality of shocks may include an ignition shock, an intake valve opening shock, an intake valve closing shock, an exhaust valve opening shock, and an exhaust valve closing shock.

[0069] For each target impact in the multiple impacts, a trapezoidal integration method can be used to determine a first area of ​​a first target interval under the envelope curve, and the first area is used as the first envelope energy of the target impact. The start and end points of the first target interval are determined based on the angle values ​​of events related to the target impact in the first valve timing table.

[0070] As an implementation, events related to target impact can be preset with a first value and a second value. The starting point of the first target interval can be the difference between the angle value of the event and the first value, and the end point of the first target interval can be the sum of the angle value of the event and the second value. The first value and the second value can both be positive numbers. Furthermore, the first value can be smaller than the second value. It should be understood that the first and second values ​​can be set according to actual needs and are not specifically limited here.

[0071] For example, let's assume the target impact is ignition impact, the event associated with ignition impact is ignition top dead center, and ignition top dead center is 360°. Assuming the first value preset for ignition top dead center is 10 and the second value is 20, under ignition impact, the starting point of the first target interval is a = 360 - 10 = 350, and the end point of the first target interval is b = 360 + 20 = 380. Where a and b are in degrees, the first target interval can be expressed as [a, b].

[0072] It should be noted that the trapezoidal integration method is a simple numerical integration method used to approximate the definite integral of a function over a certain interval. It approximates the integral by dividing the area under the curve into a series of trapezoids and calculating the areas of these trapezoids. The trapezoidal integration method is characterized by its ease of use and low computational complexity.

[0073] Furthermore, the first area of ​​the first target interval under the envelope curve can be determined using the following formula (2):

[0074]

[0075] Where E can represent the area, a can represent the starting point of the first target interval, b can represent the end point of the first target interval, N can represent the number of divided intervals, x N It can represent the Nth data point of the envelope curve.

[0076] In step S103, the second envelope energy of each of the plurality of impacts may be determined based on the envelope curve and the second valve timing table. The second valve timing table lags behind the first valve timing table by a target angle. In one example, the target angle may be 360°.

[0077] Taking the target angle as 360° as an example, when the first valve timing table is Table 1 shown below, the second valve timing table is Table 2 shown below.

[0078] Table 1: Example of the first valve timing table

[0079]

[0080] Table 2: Example of the second valve timing table

[0081]

[0082] It should be noted that deg in Tables 1 and 2 represents an angle. The first valve timing table can be considered as a valve timing table when no phase shift occurs, and the second valve timing table can be considered as a valve timing table when phase shift occurs.

[0083] When determining the second envelope energy of each of the multiple impacts, for each target impact in the multiple impacts, a trapezoidal integration method can be used to determine a second area of ​​a second target interval under the envelope curve, and the second area is used as the second envelope energy of the target impact. The start and end points of the second target interval are determined based on the angle values ​​of the event associated with the target impact in the second valve timing table. Furthermore, a formula similar to formula (2) can be used to determine the second area of ​​the second target interval under the envelope curve.

[0084] By determining the first envelope energy and the second envelope energy of each of the above-mentioned multiple impacts based on the trapezoidal integration method, the amount of calculation can be effectively reduced, the calculation efficiency can be improved, and the signal acquisition efficiency can be improved.

[0085] In step S105, the occurrence of the phase shift phenomenon can be determined based on the magnitude relationship between the first total energy and the second total energy, where the first total energy is the sum of the first envelope energies and the second total energy is the sum of the second envelope energies.

[0086] Specifically, the absence of phase shifting can be determined in response to the first total energy being greater than or equal to the second total energy. Alternatively, the presence of phase shifting can be determined in response to the first total energy being less than the second total energy. It should be noted that by determining the presence of phase shifting based on the magnitude relationship between the first total energy and the second total energy, a determination result on the presence of phase shifting can be quickly obtained, ensuring the accuracy of the determination result.

[0087] In step S107, a single-cycle second vibration signal can be extracted from the first vibration signal based on the occurrence of the phase shift phenomenon. The starting angle of the second vibration signal is 0° if the phase shift phenomenon has not occurred, and is the target angle if the phase shift phenomenon has occurred.

[0088] It should be understood that if the phase shift phenomenon does not occur, the vibration signal from 0° to 720° is intercepted from the first vibration signal as the second vibration signal. Furthermore, taking a target angle of 360° as an example, if the phase shift phenomenon occurs, the vibration signal from 360° to 1080° is intercepted from the first vibration signal as the second vibration signal.

[0089] In one embodiment, the reciprocating machine further includes at least one second cylinder, with the first cylinder being configured as a reference cylinder. In practice, the reference cylinder is a specific cylinder within the engine used for measurement and calibration. Typically, in multi-cylinder engines, a single cylinder is selected as a reference point to facilitate synchronization and control of the engine's ignition and injection timing. By monitoring the reference cylinder's ignition top dead center, the engine control system can precisely control the ignition and injection timing of other cylinders, ensuring smooth and efficient engine operation.

[0090] In the case where the reciprocating machine further comprises at least one second cylinder, and the first cylinder is configured as a reference cylinder, the following may be performed: Figure 2 The signal acquisition process shown in FIG. Figure 2 is another flow chart of the signal acquisition method provided in an embodiment of the present application. The method comprises the following steps:

[0091] S201: Determining first envelope energies of multiple impacts of the reciprocating machine based on an envelope curve of a first vibration signal of a cylinder head of a first cylinder in a double cycle in an angular domain and a first valve timing table of a standard reciprocating machine; wherein the first cylinder is configured as a reference cylinder;

[0092] S203: Determining a second envelope energy of each of the plurality of impacts based on the envelope curve and a second valve timing table, wherein the second valve timing table lags behind the first valve timing table by a target angle;

[0093] S205: Determine the occurrence of the phase shift phenomenon based on the magnitude relationship between the first total energy and the second total energy; wherein the first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies;

[0094] S207: Based on the occurrence of the phase shift phenomenon, extract a single-cycle second vibration signal from the first vibration signal;

[0095] S209: Based on the relationship between the ignition sequence and ignition interval of each second cylinder and the first cylinder, extract a single-cycle fifth vibration signal from a double-cycle fourth vibration signal of the cylinder head of each second cylinder in the angular domain.

[0096] Figure 2A corresponding embodiment provides a solution involving a reciprocating machine comprising a first cylinder and at least one second cylinder, with the first cylinder being configured as a reference cylinder. In this solution, a first envelope energy of each of multiple impacts of the reciprocating machine can be determined based on the envelope curve of a first vibration signal of the cylinder head of the first cylinder in the angular domain and a first valve timing table according to a standard for reciprocating machines. A second envelope energy of each of the multiple impacts can also be determined based on the envelope curve and a second valve timing table. The second valve timing table lags behind the first valve timing table by a target angle. The occurrence of a phase shift phenomenon can then be determined based on the relationship between the first total energy and the second total energy. Based on the occurrence of the phase shift phenomenon, a single-cycle second vibration signal can be extracted from the first vibration signal. The first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies. A single-cycle fifth vibration signal can then be extracted from the fourth vibration signal of the cylinder head of each second cylinder in the angular domain, based on the relationship between the firing order and firing interval of each second cylinder and the first cylinder. This solution uses the double-cycle first vibration signal of the cylinder head of the first cylinder in the angular domain to perform phase deviation judgment based on combined impact, and intercepts a single-cycle second vibration signal from the first vibration signal based on the occurrence of the phase deviation phenomenon, and intercepts a single-cycle fifth vibration signal from the double-cycle fourth vibration signal of the cylinder head of each second cylinder in the angular domain based on the relationship between the ignition sequence and ignition interval of each second cylinder and the first cylinder, thereby obtaining accurate cylinder head angular domain full-cycle signals of all cylinders of the reciprocating machine.

[0097] It should be noted that for the explanation of steps S201 to S207, please refer to the relevant explanation in the previous text and will not be repeated here.

[0098] Next, step S209 will be described.

[0099] In step S209 , a single-cycle fifth vibration signal may be extracted from a double-cycle fourth vibration signal of the cylinder head of each second cylinder in the angular domain based on the relationship between the ignition sequence and ignition interval of each second cylinder and the first cylinder.

[0100] The fourth vibration signal is a vibration signal between 0° and 1440°. A key phase sensor and key phase block as described above may be mounted on the flywheel of the reciprocating machine, and a vibration acceleration sensor may be mounted on the cylinder head of each second cylinder. The fourth vibration signal of a double period of the cylinder head of each second cylinder in the angular domain may be determined based on the key phase signal generated by the key phase sensor and the vibration signal collected by the vibration acceleration sensor mounted on the cylinder head.

[0101] Furthermore, a method for obtaining a double-period fourth vibration signal of the cylinder head of each second cylinder in the angular domain may include: intercepting a double-period sixth vibration signal from the vibration signal collected by a vibration acceleration sensor installed on the cylinder head based on the key phase signal generated by the key phase sensor; and converting the sixth vibration signal into a fourth vibration signal in the angular domain. It should be understood that the sixth vibration signal is a vibration signal in the time domain. When converting the sixth vibration signal into the fourth vibration signal in the angular domain, a formula similar to formula (1) mentioned above may be used for the conversion.

[0102] Taking the first cylinder as the B1 reference cylinder, the second cylinders include the A1 cylinder, the A2 cylinder, the A3 cylinder, the B2 cylinder, and the B3 cylinder, the firing order of all cylinders is A1-B2-A3-B1-A2-B3, the firing interval is 120°, and the firing angle of the B1 reference cylinder is 360° as an example, the ignition angles of all cylinders can be as shown in Table 3.

[0103] Table 3: Example of firing angles for all cylinders

[0104] Cylinder number A1 B2 A3 B1 A2 B3 Angle / deg 0 120 240 360 480 600

[0105] If the phase deviation phenomenon does not occur, the single-cycle fifth vibration signal can be intercepted from the double-cycle fourth vibration signal of the cylinder head of each second cylinder in the angular domain according to the angle range shown in Table 4.

[0106] Table 4: Example of the angle range captured by each second cylinder when not in phase

[0107] Cylinder number A1 B2 A3 A2 B3 Angle / deg 360～1080 480～1200 600～1320 120～840 240～960

[0108] If phase deviation occurs, a single-cycle fifth vibration signal can be intercepted from the double-cycle fourth vibration signal of the cylinder head of each second cylinder in the angular domain according to the angle range shown in Table 5.

[0109] Table 5: Example of the angle range captured by each second cylinder during phase shifting

[0110] Cylinder number A1 B2 A3 A2 B3 Angle / deg 0～720 120～840 240～960 480～1200 600～1320

[0111] In one embodiment, for target vibration signals with a starting angle greater than 0° in the second vibration signal and each fifth vibration signal, the target vibration signal angle range can be adjusted to a range of 0° to 720°. This standardizes the cylinder head angular domain full-cycle signals, facilitating subsequent unified comparison and analysis of the power performance of each cylinder.

[0112] Continuing with the example of the first cylinder being the B1 reference cylinder, the second cylinders include the A1 cylinder, the A2 cylinder, the A3 cylinder, the B2 cylinder, and the B3 cylinder. The key phase signal in the embodiment of the present application can be as follows: Figure 3The key phase signal shown in FIG, the first vibration signal of the cylinder head of the reference cylinder B1 can be as follows Figure 3 The fourth vibration signal of the cylinder head of the A1 cylinder can be as follows: Figure 3 The non-standard double-period signal of cylinder A1 shown in FIG, the fourth vibration signal of the cylinder head of cylinder A2 can be as follows Figure 3 The non-standard double-period signal of cylinder A2 shown in FIG, the fourth vibration signal of the cylinder head of cylinder A3 can be as follows Figure 3 The non-standard double-period signal of cylinder A3 shown in FIG, the fourth vibration signal of cylinder head of cylinder B2 can be as follows Figure 3 The non-standard double-period signal of the B2 cylinder shown in FIG, the fourth vibration signal of the cylinder head of the B3 cylinder can be as follows Figure 3 The non-standard double-cycle signal of cylinder B3 is shown in FIG. Figure 3 It is an exemplary schematic diagram of the key phase signal and the double-period vibration signal of the cylinder head of all cylinders in the angular domain in the embodiment of the present application.

[0113] If out-of-phase determination based on combined impacts is performed using the standard two-cycle signal of the B1 reference cylinder and it is determined that no out-of-phase phenomenon has occurred, a vibration signal within the range of 0° to 720° can be extracted from the standard two-cycle signal of the B1 reference cylinder. Furthermore, if the ignition angles of all cylinders are as shown in Table 3, a vibration signal within the range of 360° to 1080° can be extracted from the non-standard two-cycle signal of the A1 cylinder, a vibration signal within the range of 480° to 1200° from the non-standard two-cycle signal of the B2 cylinder, a vibration signal within the range of 600° to 1320° from the non-standard two-cycle signal of the A3 cylinder, a vibration signal within the range of 120° to 840° from the non-standard two-cycle signal of the A2 cylinder, and a vibration signal within the range of 240° to 960° from the non-standard two-cycle signal of the B3 cylinder, according to the angle ranges shown in Table 4. After that, the angle range of the vibration signal intercepted from the non-standard double-cycle signal of cylinder A1, cylinder B2, cylinder A3, cylinder A2 and cylinder B3 can be adjusted to 0° to 720°. Among them, the standard single-cycle signal of all cylinders after the angle range adjustment can be as follows Figure 4 shown. Figure 4 Schematic diagram of the standard single-cycle signal of all cylinders in the embodiment of the present application.

[0114] In one embodiment, the reciprocating machine is a diesel engine, comprising a first cylinder, at least one second cylinder, and a flywheel, wherein the first cylinder is configured as a reference cylinder. A vibration acceleration sensor is mounted on the cylinder head of each of the first and second cylinders, and a key phase sensor and a key phase block are mounted on the flywheel, with the key phase block aligned with ignition top dead center of the first cylinder.

[0115] In this embodiment, based on the key phase signal generated by the key phase sensor, a double-period third vibration signal can be intercepted from the vibration signal collected by the vibration acceleration sensor installed on the cylinder head of the first cylinder, and the third vibration signal can be converted into a first vibration signal in the angular domain. In addition, based on the key phase signal, a double-period sixth vibration signal can be intercepted from the vibration signal collected by the vibration acceleration sensor installed on the cylinder head of each second cylinder, and the sixth vibration signal can be converted into a fourth vibration signal in the angular domain.

[0116] After intercepting the first vibration signal, the Hilbert transform can be used to determine the envelope curve of the first vibration signal based on the absolute value of the first vibration signal. Next, the first envelope energy of each of the multiple impacts of the diesel engine can be determined based on the envelope curve of the first vibration signal and the first valve timing table of the diesel engine standard. The first valve timing table has the ignition top dead center at 360°. Furthermore, the second envelope energy of each of the multiple impacts can be determined based on the envelope curve of the first vibration signal and the second valve timing table. The second valve timing table lags 360° relative to the first valve timing table.

[0117] Next, the sum of the first envelope energies can be used as the first total energy, and the sum of the second envelope energies can be used as the second total energy. Based on the relationship between the first and second total energies, the occurrence of phase shifting can be determined. Based on the occurrence of phase shifting, a single-cycle second vibration signal can be extracted from the first vibration signal. The starting angle of the second vibration signal is 0° if phase shifting has not occurred and 360° if phase shifting has occurred.

[0118] Next, a single-cycle fifth vibration signal may be extracted from the fourth vibration signal of the cylinder head of each second cylinder based on the relationship between the ignition sequence and the ignition interval of each second cylinder and the first cylinder.

[0119] Then, for the target vibration signal having a starting angle greater than 0° in the second vibration signal and each of the fifth vibration signals, the angle range of the target vibration signal is adjusted to a range from 0° to 720°.

[0120] The solution provided in this embodiment can convert continuous diesel engine time-domain signals into accurate angular-domain full-cycle signals. Furthermore, it solves the "phase deviation" problem of traditional methods that segment full cycles based on key phase signals. By using a phase deviation determination method based on combined impacts, the angular-domain vibration signal within each diesel engine operating cycle is obtained, facilitating subsequent phase-based feature extraction and fault diagnosis, and improving the effectiveness and accuracy of diesel engine condition-based maintenance. This solution standardizes the angular-domain vibration signal of each cylinder by adjusting the ignition phase to 360°, facilitating subsequent unified comparison and analysis of the working performance of each cylinder. This solution uses a combination of impacts—ignition impact, intake valve opening impact, intake valve closing impact, exhaust valve opening impact, and exhaust valve closing impact—to determine the signal. It is also applicable to signals generated during misfires and abnormal intake and exhaust clearances. Furthermore, this solution is scalable and is applicable not only to diesel engines but also to other reciprocating machinery.

[0121] Figure 5 : is a schematic diagram of the structure of a signal acquisition device provided in an embodiment of the present application. The device is used to acquire a full cycle signal of a reciprocating machine, the reciprocating machine including a first cylinder, and the device includes:

[0122] A first determining module 501 is configured to determine first envelope energies of respective multiple impacts of the reciprocating machine based on an envelope curve of a first vibration signal of a cylinder head of a first cylinder in a double period in an angular domain and a first valve timing table of a reciprocating machine standard;

[0123] The second determining module 502 is configured to determine a second envelope energy of each of the plurality of impacts based on the envelope curve and a second valve timing table, wherein the second valve timing table lags behind the first valve timing table by a target angle;

[0124] The third determining module 503 is configured to determine the occurrence of the phase shift phenomenon based on the relationship between the first total energy and the second total energy; wherein the first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies;

[0125] The interception module 504 is configured to intercept a single-cycle second vibration signal from the first vibration signal based on the occurrence of the phase shift phenomenon.

[0126] In one embodiment, the reciprocating machine further comprises a flywheel, a vibration acceleration sensor is mounted on the cylinder head of the first cylinder, a key phase sensor and a key phase block are mounted on the flywheel, and a position of the key phase block is aligned with the ignition top dead center of the first cylinder;

[0127] The interception module 504 is further configured to:

[0128] Based on the key phase signal generated by the key phase sensor, a double-period third vibration signal is intercepted from the vibration signal collected by the vibration acceleration sensor;

[0129] The third vibration signal is converted into a first vibration signal in the angular domain.

[0130] In one embodiment, the first determining module 501 is further configured to:

[0131] An envelope curve is determined based on the absolute value of the first vibration signal using a Hilbert transform.

[0132] In one embodiment, the first determining module 501 is further configured to:

[0133] For each target impact among the above-mentioned multiple impacts, a trapezoidal integration method is used to determine a first area of ​​a first target interval under the envelope curve, and the first area is used as a first envelope energy of the target impact; wherein, the starting point and end point of the first target interval are determined based on the angle values ​​of events related to the target impact in the first valve timing table.

[0134] In one embodiment, the second determining module 502 is further configured to:

[0135] For each target impact among the above-mentioned multiple impacts, a trapezoidal integration method is used to determine a second area of ​​a second target interval under the envelope curve, and the second area is used as the second envelope energy of the target impact; wherein the start and end points of the second target interval are determined based on the angle values ​​of events related to the target impact in the second valve timing table.

[0136] In one embodiment, the third determining module 503 is further configured to:

[0137] In response to the first total energy being greater than or equal to the second total energy, it is determined that no out-of-phase phenomenon occurs.

[0138] In one embodiment, the third determining module 503 is further configured to:

[0139] In response to the first total energy being less than the second total energy, it is determined that an out-of-phase phenomenon occurs.

[0140] In one embodiment, the starting angle of the second vibration signal is 0° when the phase shift phenomenon does not occur, and is the target angle when the phase shift phenomenon occurs.

[0141] In one embodiment, the reciprocating machine is a diesel engine.

[0142] In one embodiment, the plurality of impacts include an ignition impact, the ignition top dead center in the first valve timing table is 360°, and the target angle is 360°.

[0143] In one embodiment, the reciprocating machine further comprises at least one second cylinder, the first cylinder being configured as a reference cylinder;

[0144] The interception module 504 is further configured to:

[0145] After intercepting a single-cycle second vibration signal from the first vibration signal, based on the relationship between the ignition sequence and ignition interval of each second cylinder and the first cylinder, a single-cycle fifth vibration signal is intercepted from the double-cycle fourth vibration signal of the cylinder head of each second cylinder in the angular domain.

[0146] In one embodiment, the interception module 504 is further configured to:

[0147] For the target vibration signal having a starting angle greater than 0° in the second vibration signal and each of the fifth vibration signals, the angle range of the target vibration signal is adjusted to a range from 0° to 720°.

[0148] It should be noted that other aspects and implementation details of the signal acquisition device provided in the embodiment of the present application are the same as or similar to the signal acquisition method described above and will not be repeated here.

[0149] In one embodiment, the present application provides a computer device comprising a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the following is achieved: Figure 1 or Figure 2 Describe the signal acquisition method.

[0150] In one embodiment, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the following Figure 1 or Figure 2 Describe the signal acquisition method.

[0151] In one embodiment, the present application provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the following Figure 1 or Figure 2 Describe the signal acquisition method.

[0152] The above description is only a partial implementation of the embodiments of the present application and does not constitute any form of limitation to the application. The protection scope of the embodiments of the present application is not limited thereto. Any simple modifications, equivalent changes and modifications that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed in the embodiments of the present application should be covered within the protection scope of the embodiments of the present application.

Claims

1. A signal acquisition method, characterized in that: For obtaining a full cycle signal of a reciprocating machine, the reciprocating machine including a first cylinder, the method comprising: Determining first envelope energies of respective multiple impacts of the reciprocating machine based on an envelope curve of a first vibration signal of a double period of the cylinder head of the first cylinder in the angular domain and a first valve timing table of a standard for the reciprocating machine; determining a second envelope energy of each of the plurality of impacts based on the envelope curve and a second valve timing table; wherein the second valve timing table lags behind the first valve timing table by a target angle; Determining the occurrence of the phase shift phenomenon based on a magnitude relationship between a first total energy and a second total energy, wherein the first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies; Based on the occurrence of the phase-out phenomenon, a single-cycle second vibration signal is intercepted from the first vibration signal.

2. The method according to claim 1, characterized in that The reciprocating machine further comprises a flywheel, a vibration acceleration sensor is mounted on the cylinder head of the first cylinder, a key phase sensor and a key phase block are mounted on the flywheel, and the position of the key phase block is aligned with the ignition top dead center of the first cylinder; The method further comprises: Based on the key phase signal generated by the key phase sensor, intercepting a double-period third vibration signal from the vibration signal collected by the vibration acceleration sensor; The third vibration signal is converted into the first vibration signal in the angular domain.

3. The method according to claim 1, characterized in that Also includes: The envelope curve is determined based on the absolute value of the first vibration signal using a Hilbert transform.

4. The method according to claim 1, wherein Determining first envelope energies of respective multiple impacts of the reciprocating machine based on an envelope curve of a first vibration signal of a double period of the cylinder head of the first cylinder in the angular domain and a first valve timing table of a standard for the reciprocating machine includes: For each target impact among the multiple impacts, a trapezoidal integration method is used to determine a first area of ​​a first target interval under the envelope curve, and the first area is used as a first envelope energy of the target impact; wherein the start and end points of the first target interval are determined based on the angle values ​​of events related to the target impact in the first valve timing table.

5. The method according to claim 1, wherein Determining, based on the envelope curve and the second valve timing table, a second envelope energy of each of the plurality of impacts, comprising: For each target impact among the multiple impacts, a trapezoidal integration method is used to determine a second area of ​​a second target interval under the envelope curve, and the second area is used as the second envelope energy of the target impact; wherein the start and end points of the second target interval are determined based on the angle values ​​of events related to the target impact in the second valve timing table.

6. The method according to claim 1, characterized in that Based on the magnitude relationship between the first total energy and the second total energy, determining the occurrence of the phase running phenomenon includes: In response to the first total energy being greater than or equal to the second total energy, it is determined that no out-of-phase phenomenon occurs.

7. The method according to claim 1, characterized in that Based on the magnitude relationship between the first total energy and the second total energy, determining the occurrence of the phase running phenomenon includes: In response to the first total energy being less than the second total energy, it is determined that an out-of-phase phenomenon occurs.

8. The method according to claim 1, characterized in that The starting angle of the second vibration signal is 0° when the phase shift phenomenon does not occur, and is the target angle when the phase shift phenomenon occurs.

9. The method according to claim 1, characterized in that The reciprocating machine is a diesel engine.

10. The method according to claim 1, characterized in that The multiple impacts include an ignition impact, the ignition top dead center in the first valve timing table is 360°, and the target angle is 360°.

11. The method according to any one of claims 1 to 10, characterized in that The reciprocating machine further includes at least one second cylinder, the first cylinder being configured as a reference cylinder; After extracting a second vibration signal of a single cycle from the first vibration signal, the method further includes: Based on the relationship between the ignition sequence and ignition interval of each second cylinder and the first cylinder, a single-cycle fifth vibration signal is intercepted from the double-cycle fourth vibration signal of the cylinder head of each second cylinder in the angular domain.

12. The method according to claim 11, characterized in that Also includes: For the target vibration signal having a starting angle greater than 0° in the second vibration signal and each of the fifth vibration signals, the angle range of the target vibration signal is adjusted to a range from 0° to 720°.

13. A signal acquisition device, characterized in that: For obtaining a full cycle signal of a reciprocating machine, the reciprocating machine including a first cylinder, the device comprising: a first determining module configured to determine first envelope energies of respective multiple impacts of the reciprocating machine based on an envelope curve of a first vibration signal of a cylinder head of the first cylinder in a double period in an angular domain and a first valve timing table of a standard for the reciprocating machine; a second determining module configured to determine a second envelope energy of each of the plurality of impacts based on the envelope curve and a second valve timing table; wherein the second valve timing table lags behind the first valve timing table by a target angle; a third determining module configured to determine the occurrence of the phase shift phenomenon based on a magnitude relationship between a first total energy and a second total energy, wherein the first total energy is the sum of the first envelope energies, and the second total energy is the sum of the second envelope energies; The interception module is configured to intercept a single-cycle second vibration signal from the first vibration signal based on the occurrence of the phase deviation phenomenon.

14. A computer device, characterized in that: The computer device includes a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the method according to any one of claims 1 to 12 is implemented.

15. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 12 is implemented.

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