Method for evaluating working reliability of ship power station prime motor (diesel engine)

Abstract

The invention relates to a ship power station prime mover (diesel engine) working reliability evaluation method, which comprises the following steps of: firstly, constructing evaluation indexes according to working characteristics of a ship power station prime mover (diesel engine), wherein the evaluation indexes comprise an inflection gear difference range, starting time, security system perfection degree, exhaust gas temperature non-uniformity of each cylinder, detonation pressure non-uniformity of each cylinder and supercharger rotating speed and load matching degree; constructing a ship power station evaluation matrix by using the evaluation index system in cooperation with index weights and state data of a plurality of units, and constructing an ideal matrix by using factory inspection report data of a prime motor (diesel engine) of the ship power station; and calculating a deviation coefficient of the evaluation matrix and the ideal matrix by using a bidirectional normalized projection algorithm specially designed for the power station diesel engine, and finally judging the working reliability of the ship power station prime motor (diesel engine) according to the value range of the deviation coefficient.

Description

Technical Field

[0001] The present invention belongs to the technical field of reliability assessment of ship power stations, and particularly relates to a method for assessing the working reliability of prime movers (diesel engines) of ship power stations. Background Art

[0002] As the core component of the ship power system, the ship power station undertakes the key task of providing stable power for the ship. The prime mover of the ship power station provides the initial mechanical energy for the generator and plays a crucial fundamental role in the power supply process. Its working reliability is directly related to the stable operation of the ship power station and the power safety of the whole ship. Due to the advantages of large power and strong adaptability, most current civilian merchant ships use diesel engines as the prime movers of the power station. However, the diesel engines of ship power stations often operate in complex marine environments and face harsh working conditions such as high load, high vibration, high humidity and frequent start-stop, resulting in a gradual decline in their working reliability.

[0003] The decline in the working reliability of the prime mover (diesel engine) of the ship power station is usually manifested as problems such as difficult starting, insufficient power, unstable speed, and even stalling midway. This not only affects the operation efficiency and safety of the ship, but also increases the maintenance cost and may even lead to serious consequences. Traditional methods for assessing the reliability of power station diesel engines mostly rely on manual experience judgment or comparison with a single parameter threshold. For example, through regular disassembly and inspection, local performance testing or isolated analysis of some operation data (such as explosion pressure, exhaust gas temperature, etc.). Such methods have obvious limitations: on the one hand, the assessment process is fragmented and it is difficult to comprehensively reflect the overall working state of the ship power station; on the other hand, they lack the ability to analyze multiple-dimensional indicators synergistically and cannot quantitatively evaluate the overall reliability level of the unit, resulting in problems such as lagging maintenance decisions and insufficient preventive maintenance. In addition, the dynamic correlation between the factory performance data of diesel engines and the actual ship operation state has not been fully utilized, further reducing the scientificity and foresight of the assessment results.

[0004] Therefore, it is of great engineering significance to develop a method for assessing the working reliability of diesel engines based on a comprehensive assessment index system, combined with the state data of multiple units and innovative algorithms. This method can comprehensively and quantitatively evaluate the working reliability of the prime movers of ship power stations, provide more scientific and accurate support for the operation management of ship power stations, thereby improving the working efficiency of ships, reducing the failure rate, lowering the maintenance cost, and extending the service life of equipment.

[0005] The present invention provides a method for evaluating the working reliability of a prime mover (diesel engine) of a ship power station. By constructing a multi-dimensional evaluation index system, integrating the real-time operation data of the unit with the factory benchmark parameters, and using a two-way regularization projection algorithm specifically designed for the diesel engine of the power station to calculate the deviation coefficient, it can scientifically and accurately achieve the quantitative evaluation of the reliability of the prime mover of the ship power station, providing technical support for the safe and efficient operation of the ship power system. Summary of the Invention

[0006] The present invention is a method for evaluating the working reliability of a prime mover (diesel engine) of a ship power station, used for evaluating the reliability of the ship power station, and specifically includes the following steps:

[0007] Step 1: Construct evaluation indexes according to the working characteristics of the prime mover (diesel engine) of the ship power station, specifically including: crankshaft deflection range s, starting time t, perfection degree c of the safety protection system, unevenness u of the exhaust gas temperature of each cylinder, unevenness p of the explosion pressure of each cylinder, matching degree m between the supercharger speed and the load. The above indexes are all represented by interval numbers, and the corresponding normalized weight vector w = (0.1, 0.2, 0.2, 0.2, 0.2, 0.1) T ;

[0008] Step 2: For the n prime movers of the ship power station generator set, use the state data matrix corresponding to the evaluation indexes established in Step 1 and the weight vector w to construct the evaluation matrix X of the prime mover of the ship power station:

[0009]

[0010] In formula (1), D is the operation state data matrix of the prime mover, and its element is an interval number (d ∈ {s, t, c, u, p, m}, i ∈ {1, 2,..., n}), is the lower bound of the interval number, is the upper bound of the interval number, W is the weight matrix generated by the normalized weight vector w according to the diagonal rule, and the multiplication operation of the evaluation matrix X follows the interval number multiplication rule, that is: where k is a real number;

[0011] Step 3: Use the factory inspection report data of the prime mover of the ship power station to construct the ideal matrix Y:

[0012]

[0013] In formula (2), D * is the factory state data matrix of the prime mover recorded in the inspection report of the marine diesel generator set, and its element is an interval number (d ∈ {s, t, c, u, p, m}, i ∈ {1, 2,..., n}), is the lower bound of the interval number, is the upper bound of the interval number, and the multiplication operation rule of the ideal matrix Y is the same as that in Equation (1);

[0014] Step 4: Calculate the projection factor φ through the following formula (3):

[0015] φ = |X||Y|(|X| 2 +|Y| 2 -2XY) (3)

[0016] In Equation (3), |X| can be calculated through the following formula:

[0017]

[0018] where x ij is the element in the i-th row and j-th column of matrix X, is the lower bound of the interval number of this element, is the upper bound of the interval number of this element;

[0019] In Equation (3), |Y| can be calculated through the following formula:

[0020]

[0021] where y ij is the element in the i-th row and j-th column of matrix Y, is the lower bound of the interval number of this element, is the upper bound of the interval number of this element;

[0022] In Equation (3), XY can be calculated through the following formula:

[0023]

[0024] where x ij is the element in the i-th row and j-th column of matrix X, is the lower bound of the interval number of this element, is the upper bound of the interval number of this element, y ij is the element in the i-th row and j-th column of matrix Y, is the lower bound of the interval number of this element, is the upper bound of the interval number of this element;

[0025] Step 5: Calculate the bidirectional normalized projection BP Y (X) of the evaluation matrix X and the ideal matrix Y to reflect the closeness between the prime mover operating state data matrix D and the prime mover factory state data matrix D* under the constraint of the weight vector w:

[0026]

[0027] where the operation rule of XY is the same as that in Equation (6);

[0028] Step 6: Calculate the deviation coefficient ζ through the following formula (8):

[0029]

[0030] Step 7: Evaluate the overall working reliability of the prime mover (diesel engine) of the ship power station according to the value range of the deviation coefficient ζ. If 0 ≤ ζ < 0.15, it indicates that the reliability of the prime mover of the ship power station is good and no treatment is required. If 0.15 ≤ ζ < 0.3, it indicates that the reliability of the prime mover of the ship power station is average and mechanical inspection and system maintenance should be arranged in a timely manner. If 0.3 ≤ ζ ≤ 1, it indicates that the reliability of the prime mover of the ship power station is poor and cylinder pulling overhaul and comprehensive inspection should be arranged immediately to prevent the occurrence of a power failure accident for the whole ship;

[0031] The beneficial effects of the present invention are as follows:

[0032] (1) By constructing a multi-dimensional evaluation index system, it can comprehensively cover the key parameters of the operating state of the prime mover (diesel engine) of the ship power station, avoid the limitations of single-index evaluation, and significantly improve the accuracy and scientific nature of reliability evaluation;

[0033] (2) Using the state data of multiple units to construct an evaluation matrix and combining the data of the factory inspection report to construct an ideal matrix, it realizes the dynamic monitoring of the operating state of the diesel engine and the comparison of historical data, can timely detect the trend of performance degradation, and provides data support for preventive maintenance;

[0034] (3) Adopting a two-way normalization projection algorithm specifically designed for power station diesel engines, it can accurately calculate the deviation coefficient between the evaluation matrix and the ideal matrix, divide the reliability level accordingly and give countermeasures, providing clear operation guidance for the operation and maintenance personnel of the ship power station, and significantly improving the operation and maintenance efficiency and economy. Description of the Drawings

[0035] Figure 1 is a flow chart of a method for evaluating the working reliability of a prime mover (diesel engine) of a ship power station involved in the present invention; Detailed Embodiments

[0036] The following further describes the detailed embodiments of the present invention with reference to the drawings:

[0037] Step 1: Construct evaluation indexes according to the working characteristics of the prime mover (diesel engine) of the ship power station, specifically including: crank web deflection range s, starting time t, perfection degree c of the safety protection system, unevenness u of the exhaust gas temperature of each cylinder, unevenness p of the explosion pressure of each cylinder, matching degree m between the supercharger speed and the load. The above indexes are all represented by interval numbers and the corresponding normalized weight vector w = (0.1, 0.2, 0.2, 0.2, 0.2, 0.1) T ;

[0038] Step 2: For the n prime movers of the ship power station generator set, use the state data matrix corresponding to the evaluation indexes established in Step 1 and the weight vector w to construct the ship power station prime mover evaluation matrix X:

[0039]

[0040] In formula (1), d is the prime mover operation state data matrix, and its element is an interval number (d ∈ {s, t, c, u, p, m}, i ∈ {1, 2, …, n}), is the lower bound of the interval number, is the upper bound of the interval number, W is the weight matrix generated by the normalized weight vector w according to the diagonal rule, and the multiplication operation of the evaluation matrix X follows the interval number multiplication rule, that is: where k is a real number;

[0041] Step 3: Use the ship power station prime mover factory inspection report data to construct the ideal matrix Y:

[0042]

[0043] In formula (2), D * is the prime mover factory state data matrix recorded in the marine diesel generator set inspection report, and its element is an interval number (d ∈ {s, t, c, u, p, m}, i ∈ {1, 2, …, n}), is the lower bound of the interval number, is the upper bound of the interval number, and the multiplication operation rule of the ideal matrix Y is the same as formula (1);

[0044] Step 4: Calculate the projection factor φ through the following formula (3):

[0045] φ = |X||Y|(|X| 2 + |Y| 2 - 2XY) (3)

[0046] In formula (3), |X| can be calculated through the following formula:

[0047]

[0048] where x ij is the element in the i-th row and j-th column of matrix X, is the lower bound of the interval number of this element, is the upper bound of the interval number of this element;

[0049] In formula (3), |Y| can be calculated through the following formula:

[0050]

[0051] where \(y\) ij is the element in the \(i\)-th row and \(j\)-th column of matrix \(Y\), is the lower bound of the interval number of this element, is the upper bound of the interval number of this element;

[0052] In formula (3), \(XY\) can be calculated by the following formula:

[0053]

[0054] where \(x\) ij is the element in the \(i\)-th row and \(j\)-th column of matrix \(X\), is the lower bound of the interval number of this element, is the upper bound of the interval number of this element, and \(y\) ij is the element in the \(i\)-th row and \(j\)-th column of matrix \(Y\), is the lower bound of the interval number of this element, is the upper bound of the interval number of this element;

[0055] Step 5: Calculate the bidirectional normalized projection \(BP(X)\) of the evaluation matrix \(X\) and the ideal matrix \(Y\) through the following formula (7) to reflect the closeness between the prime mover operating state data matrix \(D\) and the prime mover factory state data matrix \(D\) under the constraint of the weight vector \(w\): Y (X), * :

[0056]

[0057] where the operation rule of \(XY\) is the same as that of formula (6);

[0058] Step 6: Calculate the deviation coefficient \(\zeta\) through the following formula (8):

[0059]

[0060] Step 7: Evaluate the overall working reliability of the prime mover (diesel engine) of the ship power station according to the value range of the deviation coefficient \(\zeta\). If \(0\leq\zeta\lt0.15\), it indicates that the reliability of the prime mover of the ship power station is good and no treatment is required. If \(0.15\leq\zeta\lt0.3\), it indicates that the reliability of the prime mover of the ship power station is average and mechanical inspection and system maintenance should be arranged in a timely manner. If \(0.3\leq\zeta\leq1\), it indicates that the reliability of the prime mover of the ship power station is poor and cylinder overhaul and comprehensive inspection should be arranged immediately to prevent the occurrence of a power failure accident on the whole ship.

Claims

1. A method for evaluating the working reliability of a ship power station prime mover (diesel engine), characterized in that: The following steps are involved: Step 1: Construct evaluation indicators according to the working characteristics of the ship power station prime mover (diesel engine), including: turning gear difference range s, starting time t, security system perfection c, exhaust temperature unevenness of each cylinder u, explosion pressure unevenness of each cylinder p, turbocharger speed and load matching m. The above indicators are all expressed in interval numbers and the corresponding normalized weight vector w = (0.1, 0.2, 0.2, 0.2, 0.2, 0.1) T ; Step 2: For the n prime movers of the ship power station generator set, the state data matrix corresponding to the evaluation index established in step 1 is used with the weight vector w to construct the ship power station prime mover evaluation matrix X: In formula (1), D is the prime mover operation status data matrix, and its elements are is the interval number (d∈{s,t,c,u,p,m},i∈{1,2,…,n}), is the lower bound of the interval number, is the upper bound of the interval number, W is the weight matrix generated by the normalized weight vector w according to the diagonal rule, and the multiplication operation of the evaluation matrix X follows the interval number multiplication rule, that is: Where k is a real number; Step 3: Use the ship power station prime mover factory inspection report data to construct the ideal matrix Y: In formula (2), D * It is the data matrix of the factory status of the prime mover recorded in the inspection report of the marine diesel generator set. Its elements is the interval number (d∈{s,t,c,u,p,m},i∈{1,2,…,n}), is the lower bound of the interval number, is the upper bound of the interval number, and the multiplication rule of the ideal matrix Y is the same as that of formula (1); Step 4: Calculate the projection factor φ using the following formula (3): φ=|X||Y|(|X| 2 +|Y| 2 -2XY) (3) In formula (3), |X| can be calculated by the following formula: where x ij is the element in the i-th row and j-th column of matrix X, is the lower bound of the element interval number, is the upper bound of the element interval; In formula (3), |Y| can be calculated by the following formula: where y ij is the element in the i-th row and j-th column of matrix Y, is the lower bound of the element interval number, is the upper bound of the element interval; In formula (3), XY can be calculated by the following formula: where x ij is the element in the i-th row and j-th column of matrix X, is the lower bound of the element interval number, is the upper bound of the element interval, y ij is the element in the i-th row and j-th column of matrix Y, is the lower bound of the element interval number, is the upper bound of the element interval; Step 5: Calculate the bidirectional normalized projection BP of the evaluation matrix X and the ideal matrix Y by the following formula (7): Y (X) to reflect the difference between the prime mover operation state data matrix D and the prime mover factory state data matrix D under the constraint of the weight vector w. * Proximity: The operation rules of XY are the same as those in formula (6); Step 6: Calculate the deviation coefficient ζ using the following formula (8): Step 7: Evaluate the overall working reliability of the ship power station prime mover (diesel engine) according to the value range of the deviation coefficient ζ. If 0≤ζ<0.15, it indicates that the reliability of the ship power station prime mover is good and no treatment is required. If 0.15≤ζ<0.3, it indicates that the reliability of the ship power station prime mover is average, and mechanical inspection and system maintenance should be arranged in time. If 0.3≤ζ≤1, it indicates that the reliability of the ship power station prime mover is poor, and the hoisting cylinder should be repaired and comprehensively checked immediately to prevent the occurrence of power outages in the entire ship.

Images