A crankshaft stop position detection method based on key phase and toothed disc distance sensor

Abstract

A crankshaft stop position detection method based on key phase and tooth disc distance sensor relates to the technical field of equipment state monitoring. The data sequence length ratio of the original processing signal to the phase reference signal is a sequence length ratio; an adjustment function containing to-be-optimized parameters is constructed; an adjustment vector is constructed through the sequence length ratio and the adjustment function; based on the original processing signal and the adjustment vector, a fitting processing signal and a phase target are obtained; an error function of the fitting processing signal and the phase reference signal is established, a differential evolution method is used, the error function is taken as an optimization target, to-be-optimized parameters in the adjustment function are optimized, corresponding to-be-optimized parameters under the minimum value of the optimization target are calculated, and are recorded as optimal parameters; based on the optimal parameters, the phase target is calculated again, and the crankshaft stop phase is determined. The present application is helpful for analyzing the dynamic balance characteristics of the crankshaft rotation.

Description

Technical Field

[0001] This application relates to the field of equipment condition monitoring technology, and in particular to a crankshaft stop position detection method based on a key phase and gear disk distance sensor. Background Technology

[0002] Diesel engines are widely used power machines, and online monitoring of them to predict their condition changes is of great engineering significance for ensuring their safe operation and long-term reliability. Online monitoring technologies for vibration, fluid parameters, temperature, acoustic emission, cylinder pressure, instantaneous speed, torsional vibration, and output power have long been a hot topic in the field of diesel engine condition monitoring, resulting in substantial technological achievements.

[0003] The crankshaft of a diesel engine is one of the most critical moving components. Its shutdown phase refers to the angular difference between a mark on the crankshaft and a fixed reference position when the engine speed decreases until it stops. This is used to calculate the specific phase after the crankshaft stops moving. Long-term monitoring of a diesel engine and recording the shutdown phase after each shutdown, followed by statistical analysis of the long-term monitoring results, helps in analyzing the dynamic balance characteristics of the crankshaft's rotational motion. Theoretically, a good diesel engine condition means that the rotating components always maintain dynamic balance, and the shutdown phase should satisfy a random uniform distribution at any angle. If the dynamic balance deteriorates, the detected shutdown phase probability distribution will significantly deviate from the random uniform distribution; that is, within a certain small interval, the probability value of the shutdown phase is much larger than in other equally wide areas. This indicates a problem with the crankshaft's dynamic balance.

[0004] However, among diesel engine monitoring technologies, there are very few that specifically monitor the crankshaft shutdown phase mentioned above. Summary of the Invention

[0005] This application provides a crankshaft stop position detection method based on a key phase and gear plate distance sensor, belonging to the field of diesel engine fault monitoring and diagnosis technology, which helps to analyze the dynamic balance characteristics of crankshaft rotation. The steps of the technical solution are as follows:

[0006] 1. A crankshaft stop position detection method based on a key phase and gear disk distance sensor, characterized by comprising the following steps:

[0007] Install a key phase sensor and a gear tooth distance sensor to obtain the key phase signal and the gear tooth distance signal of the crankshaft flywheel gear disk for each revolution of the crankshaft. The two signals are continuously and synchronously acquired, and the threshold trigger phase of the key phase signal is marked as the crankshaft reference 0 phase.

[0008] During the phase when the equipment is running at its rated speed, the start and end times of one revolution of the crankshaft are determined by threshold triggering based on the key phase signal. Since the key phase signal and the tooth distance signal are acquired synchronously, the tooth distance signal segment corresponding to one complete revolution of crankshaft rotation with the crankshaft reference 0 phase as the starting point is extracted to obtain the phase reference signal.

[0009] During the deceleration and shutdown phase when the equipment runs at its rated speed until the speed reaches zero, the time corresponding to the last 0 phase mark before the crankshaft stops is determined by threshold triggering based on the key phase signal, and the time corresponding to the instant the crankshaft stops is determined by dynamic adaptive threshold triggering based on the gear tooth distance signal. The gear tooth distance signal between the two times is extracted to obtain the original processed signal.

[0010] The ratio of the data sequence length of the original processed signal to that of the phase reference signal is the sequence length ratio; an adjustment function containing parameters to be optimized is constructed; an adjustment vector is constructed using the sequence length ratio and the adjustment function; based on the original processed signal and the adjustment vector, the fitted processed signal and the phase target are obtained;

[0011] An error function between the fitted signal and the phase reference signal is established. Using the differential evolution method, with the error function as the optimization target, the parameters to be optimized in the adjustment function are optimized. The corresponding parameters to be optimized under the minimum value of the optimization target are calculated and denoted as the optimal parameters. Based on the optimal parameters, the phase target is calculated again to determine the crankshaft stop phase.

[0012] 2. The threshold setting of the key phase signal threshold triggering method is determined by Formula 1:

[0013] Formula 1:

[0014] thrKey = sigKey min +α·(sigKey max -sigKey min )

[0015] Where thrKey is the trigger threshold of the key phase signal; sigKey max The maximum value of the key phase signal; sigKey min The minimum value of the key phase signal is α; α is the key phase threshold calculation coefficient, which needs to be adjusted based on the first speed obtained by the tachometer that comes with the field equipment and the second speed obtained by the key phase sensor; if the second speed is greater than the first speed, the value of α is decreased, otherwise the value of α is increased, until the second speed is equal to the first speed;

[0016] 3. The threshold for the dynamic adaptive threshold triggering of the tooth distance signal is determined by formula two:

[0017] Formula 2:

[0018]

[0019] Where thrGear is the trigger threshold for the tooth distance signal; sigGear final This represents the amplitude of the gear tooth distance signal after the crankshaft has come to a complete stop; β is the calculation coefficient for the gear tooth distance signal trigger threshold, and its value should be equal to the accuracy of the on-site gear plate distance sensor.

[0020] 4. Obtain the ratio of the data sequence lengths of the original processed signal and the phase reference signal, i.e., the sequence length ratio; including:

[0021] Using Formula 3, the ratio of the data sequence length of the original processed signal to that of the phase reference signal is obtained.

[0022] Formula 3:

[0023] L B / A =L B / L A L A =length(S) A ), L B =length(S) B )

[0024] Among them, S A S is the phase reference signal. B For the original processed signal, length is the sequence length, L A L is the sequence length of the phase reference signal. B The sequence length L of the original processed signal B / A The ratio of the phase reference signal length to the length of the original processed signal sequence;

[0025] 5. Establish the adjustment function and the adjustment vector V. A The adjustment function is a combination function based on power functions and exponential functions, and its expression is Formula 4:

[0026] Formula 4:

[0027]

[0028] Wherein, F(x) is the adjustment function, e is the natural base, x is the value of the function's independent variable, and b1, b2, d1 are the first, second, and third parameters to be optimized, respectively, b1, b2, d1 ∈ (0, 1).

[0029] Let q = 1 / L A 2 / L A ,...,L A / L A Substitute the aforementioned adjustment function to establish the adjustment vector, as shown in Formula 5:

[0030] Formula 5:

[0031] V A =[1,F(1 / L) A )×L B / A ,F(2 / L A )×L B / A ,...,F(q)×L B / A ,...,F(1)×L B / A ]

[0032] Among them, V A That is, the adjustment vector; F(q) is the dependent variable value of the adjustment function F(x) calculated by substituting q as the independent variable into Formula 4; L A L is the sequence length of the phase reference signal; B / A The ratio of the phase reference signal length to the length of the original processed signal sequence;

[0033] 6. Based on the original processed signal and the adjustment vector, obtain the fitted processed signal S. C With phase target N;

[0034] Find a positive integer phase target N, and require the adjustment vector V to be... A The sum of the first N terms is less than or equal to the original processed signal S. B sequence length L B The adjustment vector V A The sum of the first N+1 terms is greater than the original processed signal S. B sequence length L B ;

[0035] Second, construct matrix T, requiring the number of rows to be equal to the sequence length L of the original processed signal. B If the matrices are equal in number and have N columns, initialize the matrix to zero.

[0036] Third, assign values ​​to matrix T column by column, letting i = 1, 2, ..., N. The requirement is that the value of matrix T in the i-th column and from the j-th to the k-th row is z; where j is numerically equal to the adjustment vector V. A The integer part of the sum of the first i terms; k is numerically equal to the adjustment vector V. A z is the integer part of the sum of the first i+1 terms; z is numerically equal to

[0037] Fourth, using Formula Six, process the original signal S. B Multiply by matrix T to obtain the fitted signal S. C ;

[0038] Formula Six:

[0039]

[0040] Where * represents matrix multiplication. The original processed signal can be considered as row 1 and column L. B Matrix; Matrix T is L B Listed as N; S C ∈R 1×N As a fitted signal, it can be regarded as a matrix with 1 row and N columns;

[0041] 7. Establish the fitted signal S C With phase reference signal S A The mean squared error is calculated; the differential evolution optimization algorithm (DE) is selected, with the goal of minimizing the mean squared error, to optimize the parameters to be optimized in the adjustment function F(x), and obtain the optimal parameters to be optimized, including:

[0042] Using Formula 7, obtain the optimal parameters to be optimized:

[0043] Formula 7:

[0044]

[0045] Among them, DE stands for Differential Evolutionary Optimization Algorithm. It is a widely used optimization algorithm with a standard process. It only requires setting the initial parameters, the parameters to be optimized, the optimization objective, and the optimization direction to obtain the value of the parameters to be optimized in the optimal case of the optimization objective in the optimization direction.

[0046] Initial parameters include: population size = 50, mutation probability = 0.5, and maximum number of training iterations = 200.

[0047] The parameters to be optimized are the first, second, and third parameters to be optimized, b1, b2, d1 ∈ (0, 1);

[0048] The optimization direction is to minimize;

[0049] The optimization goal is in, To fit the signal S C The value of the i-th sequence point; For phase reference signal S A The value of the i-th sequence point; N is the fitted signal S. C The number of columns;

[0050] (b1,b2,d1) best That is, in optimizing the objective In the minimum case, the differential evolution algorithm gives the values ​​of b1, b2, d1.

[0051] 8. In (b1, b2, d1) best In this case, recalculate the phase target N. best Determine the crankshaft shutdown phase; including:

[0052] (b1, b2, d1) best Substituting into Formula 4, we can calculate the adjustment function at this point, denoted as F(x). best ; this F(x) best Substituting into Formula 5, we calculate the adjustment vector at this point, denoted as... Find a positive integer N best The requirements stated The first N best The sum of the terms is less than or equal to the sequence length L of the phase reference signal. A The The first N best The sum of the +1 terms is greater than the sequence length L of the phase reference signal. A Based on the positive integer N best Use Formula 8 to calculate the shutdown phase;

[0053] Formula 8:

[0054]

[0055] Where, N best For the recalculated phase target, L A is the length of the phase reference signal sequence; ang is the crankshaft stopping phase. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 This is a flowchart of an online monitoring method for crankshaft shutdown phase of a diesel engine, according to an embodiment of this application.

[0058] Figure 2 This is a schematic diagram illustrating the specific steps of an online monitoring method for crankshaft shutdown phase of a diesel engine, according to an embodiment of this application.

[0059] Figure 3According to an embodiment of this application, a method for collecting key phase signals of a diesel engine before and after shutdown is provided;

[0060] Figure 4 According to an embodiment of this application, a tooth distance signal before and after machine stop is provided.

[0061] Figure 5 According to an embodiment of this application, a tooth distance signal, i.e., the original processed signal, is provided after being intercepted with reference start point and reference end point;

[0062] Figure 6 This is a standard reference signal for acquisition provided according to an embodiment of this application;

[0063] Figure 7 This is a schematic diagram comparing a parameter-optimized fitted signal with a standard reference signal, according to an embodiment of this application. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings. The following description uses an example of a computer device determining the crankshaft stopping phase during a certain stopping process using a crankshaft stopping position detection method based on a key phase and gear plate distance sensor, as described in this application.

[0065] Step (1): Install a key phase sensor and a gear tooth distance sensor to obtain the key phase signal and the gear tooth distance signal of the crankshaft flywheel gear per revolution of the crankshaft, respectively. These two signals are continuously and synchronously acquired, and the threshold trigger phase of the key phase signal is marked as the crankshaft reference 0 phase. In this embodiment, the synchronously acquired diesel engine key phase signal is as follows: Figure 3 As shown, the gear tooth distance signal is as follows Figure 4 As shown.

[0066] The threshold setting of the key phase signal threshold triggering method in step (2) is determined by formula one:

[0067] Formula 1:

[0068] thrKey = sigKey min +α·(sigKey max -sigKey min )

[0069] Where thrKey is the trigger threshold of the key phase signal; sigKey max The maximum value of the key phase signal; sigKey minThe minimum value of the key phase signal is given by α, which is the key phase threshold calculation coefficient. It needs to be adjusted based on the first speed obtained by the tachometer that comes with the field equipment and the second speed obtained by the key phase sensor. If the second speed is greater than the first speed, the value of α is decreased; otherwise, the value of α is increased until the second speed is equal to the first speed.

[0070] In this embodiment, the key phase threshold calculation coefficient for the key phase sensing is α = 0.6, and the key phase trigger threshold thrKey = 1.08 is determined by Formula 1. The rising edge triggering method can be selected, and the index address of the data point corresponding to the last key phase pulse crossing the trigger threshold is determined to be 29670, which is the reference starting point.

[0071] The threshold for the dynamic adaptive threshold triggering of the tooth distance signal is determined by formula two:

[0072] Formula 2:

[0073]

[0074] Where thrGear is the trigger threshold for the tooth distance signal; sigGear final This represents the amplitude of the gear tooth distance signal after the crankshaft has come to a complete stop; β is the calculation coefficient for the gear tooth distance signal trigger threshold, and its value should be equal to the accuracy of the on-site gear plate distance sensor.

[0075] In this embodiment, the tooth distance signal trigger threshold calculation coefficient β = 0.001 is used. The tooth distance signals are arranged in reverse order, and the first point where the fluctuation of the reversed signal exceeds thrGear is determined by Formula 2. This point is the reference end point; the final distance value is maintained at around 23.86, then Thr rod For (23.83, 23.88), such as Figure 4 It can be detected that the index value at 44903 is 23.89, which exceeds the limit, and the reference end point 44903 is obtained.

[0076] Step (3) Obtaining the ratio of the data sequence lengths of the original processed signal and the phase reference signal, i.e., the sequence length ratio; including:

[0077] Using Formula 3, the ratio of the data sequence length of the original processed signal to that of the phase reference signal is obtained.

[0078] Formula 3:

[0079] L B / A =L B / L A L A =length(S) A ), L B=length(S) B )

[0080] Among them, S A S is the phase reference signal. B For the original processed signal, length is the sequence length, L A L is the sequence length of the phase reference signal. B The sequence length L of the original processed signal B / A The ratio of the phase reference signal length to the length of the original processed signal sequence;

[0081] In this embodiment of the application, the tooth distance signal segment between the aforementioned reference start point and reference end point is extracted to obtain the original processed signal, such as... Figure 5 As shown, a set of tooth distance signals at standard rotational speeds is obtained and used as a phase reference signal, such as... Figure 6 As shown. The phase reference signal S is obtained. A With the original processed signal S B The ratio of the sequence length of the phase reference signal to that of the reference signal is used to obtain L. A =513, L B =44903, L B / A =25627 / 513=87.53.

[0082] Step (4) Establish the adjustment function and the adjustment vector V A The adjustment function is a combination function based on power functions and exponential functions, and its expression is Formula 4:

[0083] Formula 4:

[0084]

[0085] Where F(x) is the adjustment function, e is the natural base, x is the value of the function's independent variable, and b1, b2, d1 are the first, second, and third parameters to be optimized, respectively, b1, b2, d1 ∈ (0, 1).

[0086] Let q = 1 / L A 2 / L A ,...,L A / L A Substitute the aforementioned adjustment function to establish the adjustment vector, as shown in Formula 5:

[0087] Formula 5:

[0088] V A =[1,F(1 / L) A )×L B / A ,F(2 / L A )×L B / A,...,F(q)×L B / A ,...,F(1)×L B / A ]

[0089] Among them, V A That is, the adjustment vector; F(q) is the dependent variable value of the adjustment function F(x) calculated by substituting q as the independent variable into Formula 4; L A L is the sequence length of the phase reference signal; B / A The ratio of the phase reference signal length to the length of the original processed signal sequence;

[0090] In this embodiment, initial values ​​of b1, b2, d1 are set to 0.5, 0.5, 0.5, and an adjustment function is established.

[0091] Then the adjustment vector

[0092]

[0093] Step (5): Based on the original processed signal and the adjustment vector, obtain the fitted processed signal S. C With phase target N;

[0094] First, find a positive integer phase target N, which requires the adjustment vector V to... A The sum of the first N terms is less than or equal to the original processed signal S. B sequence length L B The adjustment vector V A The sum of the first N+1 terms is greater than the original processed signal S. B sequence length L B ;

[0095] Second, construct matrix T, requiring the number of rows to be equal to the sequence length L of the original processed signal. B If the matrices are equal in number and have N columns, initialize the matrix to zero.

[0096] Third, assign values ​​to matrix T column by column, letting i = 1, 2, ..., N. The requirement is that the value of matrix T in the i-th column and from the j-th to the k-th row is z; where j is numerically equal to the adjustment vector V. A The integer part of the sum of the first i terms; k is numerically equal to the adjustment vector V. A z is the integer part of the sum of the first i+1 terms; z is numerically equal to

[0097] Fourth, using Formula Six, process the original signal S. B Multiply by matrix T to obtain the fitted signal S. C ;

[0098] Formula Six:

[0099]

[0100] Where * represents matrix multiplication. The original processed signal can be considered as row 1 and column L. B Matrix; Matrix T is L B Listed as N; S C ∈R 1×N As a fitted signal, it can be regarded as a matrix with 1 row and N columns;

[0101] Step (6): Establish the fitted signal S C With phase reference signal S A The mean squared error is calculated; the differential evolution optimization algorithm (DE) is selected, with the goal of minimizing the mean squared error, to optimize the parameters to be optimized in the adjustment function F(x), and obtain the optimal parameters to be optimized, including:

[0102] Using Formula 7, obtain the optimal parameters to be optimized:

[0103] Formula 7:

[0104]

[0105] Among them, DE stands for Differential Evolutionary Optimization Algorithm. It is a widely used optimization algorithm with a standard process. It only requires setting the initial parameters, the parameters to be optimized, the optimization objective, and the optimization direction to obtain the value of the parameters to be optimized in the optimal case of the optimization objective in the optimization direction.

[0106] Initial parameters include: population size = 50, mutation probability = 0.5, and maximum number of training iterations = 200.

[0107] The parameters to be optimized are the first, second, and third parameters to be optimized, b1, b2, d1 ∈ (0, 1);

[0108] The optimization direction is to minimize;

[0109] The optimization goal is in, To fit the signal S C The value of the i-th sequence point; For phase reference signal S A The value of the i-th sequence point; N is the fitted signal S. C The number of columns;

[0110] (b1,b2,d1) best That is, in optimizing the objective In the minimum case, the differential evolution algorithm gives the values ​​of b1, b2, d1.

[0111] In the embodiments of this application, (b1,b2,d1) best =0.3, 0.08, 0.61;

[0112] Step (7) is in (b1,b2,d1) best In this case, recalculate the phase target N. best Determine the crankshaft shutdown phase; including:

[0113] (b1, b2, d1) best Substituting into Formula 4, we can calculate the adjustment function at this point, denoted as F(x). best ; this F(x) best Substituting into Formula 5, we calculate the adjustment vector at this point, denoted as... Find a positive integer N best The requirements stated The first N best The sum of the terms is less than or equal to the original processed signal S. B sequence length L B The The first N best The sum of +1 terms is greater than the original processed signal S. B sequence length L B Based on the positive integer N best Use Formula 8 to calculate the shutdown phase;

[0114] Formula 8:

[0115]

[0116] Where, N best For the recalculated phase target, L A is the length of the phase reference signal sequence; ang is the crankshaft stopping phase.

[0117] In the embodiments of this application, in (b1,b2,d1) best =0.3, 0.08, 0.61

[0118] Calculate N best =260, that is, a positive integer phase target of 260, the adjustment vector V A The sum of the first 260 terms is less than or equal to the original processed signal S. B sequence length L B =44903, the adjustment vector V AThe sum of the first 261 terms is greater than the original processed signal S. B sequence length L B =44903; then ang = 260 / 513 × 360° = 182.81°, and the results of fitting the processed signal and the phase reference signal are as follows. Figure 7 As shown.

Claims

1. A crankshaft stop position detection method based on a key phase and gear disk distance sensor, characterized in that, Includes the following steps: Install a key phase sensor and a gear tooth distance sensor to obtain the key phase signal and the gear tooth distance signal of the crankshaft flywheel gear disk for each revolution of the crankshaft. The two signals are continuously and synchronously acquired, and the threshold trigger phase of the key phase signal is marked as the crankshaft reference 0 phase. During the phase when the equipment is running at its rated speed, the start and end times of one revolution of the crankshaft are determined by threshold triggering based on the key phase signal. Since the key phase signal and the tooth distance signal are acquired synchronously, the tooth distance signal segment corresponding to one complete revolution of crankshaft rotation with the crankshaft reference 0 phase as the starting point is extracted to obtain the phase reference signal. During the deceleration and shutdown phase when the equipment is running at its rated speed until the speed reaches zero, the time corresponding to the last 0 phase mark before the crankshaft stops is determined by threshold triggering based on the key phase signal, and the time corresponding to the instant the crankshaft stops is determined by dynamic adaptive threshold triggering based on the gear tooth distance signal. The gear tooth distance signal between the two times is extracted to obtain the original processed signal. The ratio of the data sequence length of the original processed signal to that of the phase reference signal is the sequence length ratio. Construct an adjustment function containing parameters to be optimized; construct an adjustment vector using the sequence length ratio and the adjustment function; obtain the fitted processed signal and the phase target based on the original processed signal and the adjustment vector; An error function between the fitted signal and the phase reference signal is established. Using the differential evolution method, with the error function as the optimization target, the parameters to be optimized in the adjustment function are optimized. The corresponding parameters to be optimized under the minimum value of the optimization target are calculated and denoted as the optimal parameters. Based on the optimal parameters, the phase target is calculated again to determine the crankshaft stop phase.

2. The method according to claim 1, characterized in that, The threshold setting of the key phase signal threshold triggering method is determined by formula 1: Formula 1: ;in, The trigger threshold for the key phase signal; The maximum value of the bond phase signal; This is the minimum value of the bond phase signal; The coefficient for calculating the key phase threshold needs to be adjusted based on the first rotational speed obtained from the tachometer that comes with the field equipment and the second rotational speed obtained from the key phase sensor; if the second rotational speed is greater than the first rotational speed, then the coefficient should be reduced. Value, otherwise increase The value is adjusted until the second speed equals the first speed.

3. The method according to claim 1, characterized in that, The threshold for the dynamic adaptive threshold triggering of the tooth distance signal is determined by formula two: Formula 2: ;in, The trigger threshold for the tooth distance signal; This indicates the amplitude of the gear tooth distance signal after the crankshaft has come to a complete stop; The coefficient for calculating the trigger threshold of the tooth distance signal should be equal to the accuracy of the on-site tooth disk distance sensor.

4. The method according to claim 1, characterized in that, Obtain the ratio of the data sequence lengths of the original processed signal and the phase reference signal, i.e., the sequence length ratio; include: Using Formula 3, the ratio of the data sequence length of the original processed signal to that of the phase reference signal is obtained. Formula 3: ;in, As a phase reference signal, The original processed signal, That is, to find the length of the sequence. The sequence length of the phase reference signal. The sequence length of the original processed signal. This is the ratio of the phase reference signal length to the length of the original processed signal sequence.

5. The method according to claim 1, characterized in that, Establish the adjustment function and the adjustment vector The adjustment function is a combination function based on power functions and exponential functions, and its expression is Formula 4: Formula 4: ;in, Let e ​​be the adjustment function, and x be the value of the function's independent variable. These are the first, second, and third parameters to be optimized. ; make Substitute the aforementioned adjustment function to establish the adjustment vector, as shown in Formula 5: Formula 5: ;in, That is, the adjustment vector; That is, the adjustment function calculated by substituting q as the independent variable into Formula 4. The value of the dependent variable; The sequence length of the phase reference signal; This is the ratio of the phase reference signal length to the length of the original processed signal sequence.

6. The method according to claim 1, characterized in that, Based on the original processed signal and the adjustment vector, the fitted processed signal is obtained. With phase target N; Find a positive integer phase target N, and require the adjustment vector to... The sum of the first N terms is less than or equal to the original processed signal. sequence length The adjustment vector The sum of the first N+1 terms is greater than the original processed signal. sequence length ; Second, construct matrix T, requiring the number of rows to be equal to the sequence length of the original processed signal. If the matrices are equal in number and have N columns, initialize the matrix to zero. Third, assign values ​​to matrix T column by column, letting i = 1, 2, ..., N. The requirement is that the value of matrix T in the i-th column and from the j-th to the k-th row is z; where j is numerically equal to the adjustment vector. The integer part of the sum of the first i terms; k is numerically equal to the adjustment vector. z is the integer part of the sum of the first i+1 terms; z is numerically equal to ; Fourth, using Formula Six, process the original signal. Multiply by matrix T to obtain the fitted signal. ; Formula Six: ;in, For matrix multiplication, The original processed signal can be considered as behavior 1, listed as... Matrix; Matrix T behavior , categorized as N; As a fitted signal, it can be viewed as a matrix with 1 row and N columns.

7. The method according to claim 5, characterized in that, Establish fitting signal processing With phase reference signal The mean square error is calculated; the differential evolution optimization algorithm (DE) is selected, with the goal of minimizing the mean square error, and the adjustment function is adjusted accordingly. The parameters to be optimized are minimized to obtain the optimal parameters, including: Using Formula 7, obtain the optimal parameters to be optimized: Formula 7: Among them, DE stands for Differential Evolutionary Optimization Algorithm, which is a widely used optimization algorithm with a standard procedure. It only requires setting the initial parameters, the parameters to be optimized, the optimization objective, and the optimization direction to obtain the value of the parameters to be optimized in the optimal case of the optimization objective in the optimization direction. Initial parameters include: population size = 50, mutation probability = 0.5, and maximum number of training iterations = 200. The parameters to be optimized are the first, second, and third parameters. ; Optimization direction is minimize; The optimization goal is ,in, For fitting signal processing The value of the i-th sequence point; Phase reference signal The value of the i-th sequence point; N is the fitted signal. The number of columns; That is, in optimizing the objective In the minimum case, the differential evolution algorithm gives... The value of .

8. The method according to claim 7, characterized in that, exist In this case, recalculate the phase target. Determine the crankshaft shutdown phase; include: Will Substituting into Formula 4, we calculate the adjustment function at this point, denoted as... ; will Substituting into Formula 5, we calculate the adjustment vector at this point, denoted as... Find a positive integer The requirements are as follows The former The sum of the terms is less than or equal to the original processed signal. sequence length The The former The sum of +1 terms is greater than the original processed signal. sequence length Based on this positive integer Use Formula 8 to calculate the shutdown phase; Formula 8: ;in, For the recalculated phase target, The length of the phase reference signal sequence; This is the crankshaft stopping phase.

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