Equipment maintenance quality evaluation method for water-turbine generator set

Abstract

The invention relates to the technical field of maintenance of water-turbine generator sets, in particular to an equipment maintenance quality evaluation method for a water-turbine generator set, which comprises the following steps: performing hierarchical division on the water-turbine generator set until the water-turbine generator set is divided and decomposed into a minimum maintenance unit or inspection item which is called as a state evaluation item; setting weights according to the importance degree of the lower hierarchy to the performance and safe and reliable operation of the upper hierarchy; performing performance degradation degree evaluation on the state evaluation item; the health degree of each state evaluation item is calculated through the weight and the degradation deduction value, and then the equipment health degree of the corresponding level is obtained through step-by-step calculation; and the equipment health degree of the water turbine generator set before and after each level of maintenance is calculated, then the maintenance quality improvement rate is calculated, and the higher the maintenance quality improvement rate is, the better the maintenance effect is. According to the method, through comprehensive evaluation of the maintenance decision, the maintenance process and the maintenance result, scientific evaluation of the whole maintenance process is realized, the contribution condition of maintenance work to maintenance of equipment health is truly reflected, and a scientific basis is provided for the maintenance decision.

Description

Technical Field

[0001] The invention belongs to the technical field of maintenance of hydro-generator sets, and in particular relates to an equipment maintenance quality evaluation method for hydro-generator sets. Background Art

[0002] Although there are relevant installation, testing and inspection standards for newly designed units at home and abroad, there is no unified standard system for the quality assessment of hydropower equipment maintenance at home and abroad. The existing maintenance evaluation standards are characterized by high fragmentation, great differentiation, independence, and inconsistent standards. The evaluation methods in the industry vary, the evaluation content and standards are self-determined, the evaluation basis is insufficient, the evaluation standards are vague and subjective, and they are not universally adaptable, flexible, and extensible, which causes differences among the participants in the maintenance project in the project acceptance evaluation, and is not conducive to the power maintenance technical service companies and users to quickly, accurately, scientifically, and reasonably carry out preventive maintenance based on diagnosis and evaluation. There is no relevant evaluation standard system to support the quality, effect, and contribution of the power generation equipment after maintenance, which cannot adapt to and meet the current evaluation requirements of power maintenance technical service companies and users for equipment maintenance and maintenance projects, hindering the healthy development of power generation equipment maintenance and maintenance.

[0003] Although the existing hydropower equipment maintenance evaluation methods have their own advantages, they generally have the following common disadvantages: (1) High degree of fragmentation: The maintenance status evaluation items of hydro-turbine generator sets are relatively fragmented, incomplete and inconsistent in standards.

[0004] (2) Limited applicability: The existing maintenance evaluation specifications and standards only meet the equipment maintenance evaluation requirements of the compiling enterprises and are difficult to meet all application needs.

[0005] (3) Inability to flexibly expand: All existing maintenance evaluation methods are affected by changes in the types and number of maintenance evaluation items, and cannot meet the universal adaptability and flexible expansion requirements between different maintenance projects and between different maintenance companies, power plants, supervisors and equipment manufacturers of the same project.

[0006] (4) Evaluation methods are vague: All existing maintenance evaluation methods are formulated arbitrarily. The scores and weights vary according to the maintenance evaluation items and the technical capabilities of the personnel. They are greatly influenced by human factors and are highly subjective.

[0007] (5) Insufficient quantification of evaluation indicators: All existing maintenance evaluation methods lack quantitative indicators, the evaluation standards are not operational, the evaluation efficiency is low, and the evaluation results of different evaluators using the same evaluation method vary greatly.

[0008] (6) No evaluation standard for the effect of maintenance quality improvement: All existing maintenance evaluation methods have not established relevant evaluation methods for the effect of maintenance quality improvement of hydropower equipment, and cannot truly reflect the contribution of maintenance work to maintaining the health of equipment.

[0009] These shortcomings and deficiencies have posed new challenges to the development of maintenance quality evaluation technology for hydropower equipment, forcing researchers to continuously explore and study new evaluation methods to improve the maintenance evaluation capabilities of hydropower equipment in industries such as power equipment maintenance technical service companies, power companies, and equipment manufacturers, further standardize the maintenance evaluation behavior of the entire power maintenance technical service industry, and achieve the goal of professional and precise maintenance of hydropower equipment. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide a method for evaluating the quality of equipment maintenance for a hydro-turbine generator set. By comprehensively evaluating the maintenance decision, maintenance process and maintenance results, a scientific evaluation of the entire maintenance process is achieved, the contribution of the maintenance work to maintaining the health of the equipment is truly reflected, and a scientific basis is provided for maintenance decisions.

[0011] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for evaluating the equipment maintenance quality of a hydro-generator set, comprising the following steps: Step 1: divide the hydro-generator units into levels until they are decomposed into the smallest maintenance unit or inspection item, which is called the status evaluation item; Step 2: Set weights based on the importance of the lower level to the performance and safe and reliable operation of the upper level; Step 3: Evaluate the performance degradation degree of the status evaluation items; Step 4: Calculate the health of each status evaluation item by weight and degradation deduction value, and then calculate the health of the equipment at the corresponding level step by step; Step 5. According to steps 3 and 4, calculate the equipment health status of each level of the hydro-turbine generator set before and after maintenance, and then calculate the maintenance quality improvement rate. The higher the maintenance quality improvement rate, the better the maintenance effect.

[0012] In the preferred solution, in step one, the hydro-generator set is decomposed in the order of "professional-subsystem-key component-secondary component-inspection item".

[0013] In a preferred solution, in step 2, each level is divided into levels according to importance, and each level corresponds to a different weight.

[0014] In the preferred solution, in step 3, the status evaluation items are graded from light to heavy according to the degree of degradation, and each level corresponds to a different basic deduction value, and a deduction rule is obtained. The status evaluation items are deducted according to the deduction rule to obtain a deduction value. y 0, the degradation deduction value is calculated according to the following formula y Used to characterize the degree of degradation: (1); in, x is the weight of the status evaluation item.

[0015] In the preferred solution, in step 4, the health of the status evaluation item is calculated using the following formula: (2); In the formula, a Indicates the health of the status evaluation item, y Indicates the degradation penalty value of the status evaluation item.

[0016] In the preferred solution, in step 4, the health of the secondary component Corresponding status evaluation item health a and the weight of the status evaluation item x The conversion relationship is calculated according to formula (3): (3); Where: Indicates the health of the status evaluation item in the lower level corresponding to the secondary component, Represents the weight of the status evaluation item in the lower level corresponding to the secondary component, n Indicates the number of status evaluation items in the lower level corresponding to the secondary component; Key component health The health of the corresponding secondary components and secondary component weights The conversion relationship is calculated according to formula (4): (4); Where: Indicates the health of the secondary components in the lower level corresponding to the key components. Indicates the weight of the secondary component in the lower level corresponding to the key component. m Indicates the number of secondary components in the lower level corresponding to the key component.

[0017] In a preferred solution, the key status evaluation item is marked in the status evaluation items in the lower level corresponding to the secondary component, and the key status evaluation item is recorded as , if the secondary component health <Key status evaluation item health ,but: (5); If the secondary component health >Key status evaluation item health ,but: (6); Mark the key second-level components in the lower-level components corresponding to the key components. The health of the key second-level components is If the health of key components <Health of key secondary components ,but: (7); If the health of key components >Health of key secondary components ,but: (8); Each subsystem is composed of multiple key components. The health of a single subsystem is determined by the health of the key components at the next level. The health of a subsystem is equal to the minimum health of the key components at the next level.

[0018] In the preferred scheme, in step four, the equipment status is evaluated according to the calculated health level: the health level is divided into intervals, and the health level is divided into "normal state", "caution state", "abnormal state" and "dangerous state" from high to low, and the status of the equipment is judged according to the interval in which the health level of the calculated status evaluation item is located.

[0019] In a preferred solution, the evaluation rule for judging the state of the device according to the interval in which the health of the state evaluation item is located is: When all equipment status evaluation items are evaluated as "normal status", the overall equipment evaluation is "normal status"; When all status evaluation items corresponding to the second-level component are evaluated as "normal state", the second-level component is evaluated as "normal state"; When any status evaluation item of a secondary component is "caution status", "abnormal status" or "dangerous status", the secondary component is evaluated as the most serious status.

[0020] In the preferred solution, the maintenance quality improvement rate includes four levels: maintenance quality improvement rate of status evaluation items, maintenance quality improvement rate of secondary components, maintenance quality improvement rate of key components, and maintenance quality improvement rate of subsystems. The expressions are as follows: 1) Repair quality improvement rate of status evaluation items The maintenance quality improvement rate of the status evaluation item Δ and the health degree of the status evaluation item before maintenance a 0 and the health of the status evaluation item after repaira The transformation relationship is calculated according to formula (9): Δ= a - a 0 (9); 2) Secondary component maintenance quality improvement rate Secondary component overhaul quality improvement rate Δ' and secondary component pre-repair health and the secondary component repair health The transformation relationship is calculated according to formula (10): (10); 3) Quality improvement rate of key component maintenance Quality improvement rate of key component maintenance Health of key components before repair and the health of key components after repair The transformation relationship is calculated according to formula (11): (11); 4) Subsystem maintenance quality improvement rate When a subsystem has multiple key components and corresponds to multiple key component health levels and key component maintenance quality improvement rates, the maintenance quality improvement rate of the subsystem can be calculated by the arithmetic mean of the maintenance quality improvement rates of each key component.

[0021] The present invention provides a method for evaluating the quality of equipment maintenance of a hydro-generator set, which has the following beneficial effects: 1. High integration: All maintenance evaluation items of vertical turbine generator sets are decomposed layer by layer according to the smallest unit, and the evaluation content is comprehensive, rich and unified.

[0022] 2. Strong applicability: This maintenance quality evaluation method combines the research results and experience of power maintenance companies, power companies, equipment manufacturers and related industries at home and abroad to meet all application needs of various enterprises in the industry.

[0023] 3. Quantification and qualitative analysis: According to the equipment inspection and maintenance requirements, all key components are quantitatively or qualitatively described in terms of various technical indicators, performance, operating status and other parameters to directly or indirectly characterize the equipment status. The evaluation standard is highly operational and efficient. The evaluation results of different evaluators using this evaluation method have little difference and are highly operational.

[0024] 4. Strong scientificity: This maintenance quality evaluation method adopts the hierarchical analysis method and the comprehensive evaluation method. The weights and deduction values ​​are determined according to the comprehensive impact of the health of the minimum unit state quantity of equipment maintenance on related components and operating systems. The weights and deduction values ​​do not change with the changes in the maintenance evaluation items and the technical capabilities of the personnel. The human factor influence is small, the evaluation is highly objective, the application and implementation are simple, and the conclusions are objective and feasible.

[0025] 5. Modular design: The maintenance quality evaluation can be flexibly combined according to the actual maintenance content, and is not affected by changes in the category and number of maintenance evaluation items. It meets the general adaptability and flexible scalability between different maintenance projects and between different maintenance companies, power plants, supervisors and equipment manufacturers of the same project.

[0026] 6. Good evaluation of maintenance quality improvement effect: This maintenance evaluation method is an evaluation method established for the maintenance quality improvement effect of hydropower equipment, which can truly reflect the contribution of maintenance work to maintaining the health of equipment.

[0027] 7. The selected evaluation index data are easy to obtain and quantifiable, the evaluation standards follow the qualitative and quantitative principles, and the evaluation process and results are less affected by human factors. It is of great significance to build equipment maintenance evaluation capabilities for the power industry, deepen the application of maintenance evaluation, standardize the entire power technical service industry market, and achieve professional and precise maintenance goals, and to improve the quality and service level of the entire power maintenance technical service. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a schematic diagram of the process of the present invention; Figure 2 This is a classification structure diagram of the evaluation objects for river basin power station maintenance (equipment type). DETAILED DESCRIPTION

[0030] Combination Figure 1~2 The specific embodiments of the present invention are described in further detail.

[0031] It is clear and complete that the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] This method mainly uses the offline disassembly inspection data, system defect data, historical operation and maintenance data, online status monitoring data, specific test data and other data of the unit during the A-level and B-level maintenance of the unit to study the correlation and impact of the key indicators and relevant technical standards of the unit design, manufacturing, process, installation and operation and maintenance technology, and conduct a comprehensive evaluation of each component (or inspection item) from the aspects of availability, maintenance, performance, safety and reliability, and scientifically evaluate the single and overall maintenance process and results of the unit, using quantitative evaluation and visual evaluation methods. Establish a maintenance evaluation standard system to help maintenance companies and power plant users analyze and determine the current health status of the unit as a whole and its components, propose professional and accurate maintenance, improvement or transformation measures, as well as treatment suggestions and recommended spare parts lists for equipment operation defects, evaluate whether the unit components or subsystems are necessary for maintenance and upgrading, and reversely evaluate the importance and necessity of maintenance projects based on the maintenance benefits after the equipment maintenance, so as to provide a basis for maintenance companies and power plant users to carry out maintenance, technical transformation and other projects, and ultimately achieve professional and precise maintenance, improve the quality of maintenance work, improve maintenance work efficiency, reduce maintenance operation costs and labor intensity, and avoid ineffective maintenance and excessive maintenance.

[0033] A method for evaluating the quality of equipment maintenance of a hydro-generator set comprises the following steps: Step 1: Divide the hydro-generator sets into levels until they are decomposed into the smallest maintenance unit or inspection item. The smallest maintenance unit or inspection item is called a status evaluation item.

[0034] The hydro-generator set is decomposed in the order of “professional-subsystem-key component-secondary component-inspection item”.

[0035] 1. The equipment subject to maintenance evaluation refers to the turbine generator sets in the Yangtze River Power Basin Power Station, including vertical shaft mixed flow units and vertical shaft axial flow propeller units. According to the structural type of the turbine generator sets in the basin power station and the independence and scale of each component, they can be divided in the following ways.

[0036] 1) Turbine and its auxiliary equipment. Mainly including Francis runner, axial flow propeller runner, water guide mechanism, water guide bearing, air supply system, oil receiver and operating oil pipeline system, top cover drainage system, support cover drainage system, flow-through components, main shaft seal, cylinder valve system, speed control system, oil, water and gas system and related control systems.

[0037] 2) Generator and its auxiliary equipment. Mainly including stator, rotor, slip ring and carbon brush, upper frame and upper guide bearing, thrust (guide) bearing, dust collection system, oil mist absorption system, mechanical brake system, ventilation and cooling system, grounding device, excitation system, high-pressure oil system and related control system.

[0038] 2. Classification principles Each subsystem may be composed of one or more key components, each key component may be composed of one or more secondary components, and each secondary component may be composed of one or more status evaluation items.

[0039] The following classification principles for equipment evaluation objects are mainly summarized and classified according to the unit maintenance business, ultimately ensuring that the maintenance evaluation units are minimized and the maintenance evaluation items are fully covered.

[0040] 1) The first-level evaluation objects are classified according to the type of hydro-turbine generator sets, including: mixed flow type and axial flow type; 2) The second level evaluation objects are classified by profession, mainly including: mechanical and electrical; 3) The third-level evaluation objects are classified according to subsystems. Taking the evaluation system of the Francis unit machinery as an example, its evaluation subsystems include: turbine, generator, governor, cylinder valve, operation stability subsystem, etc.; 4) The fourth-level evaluation objects are classified according to the key components of the unit subsystem. Taking the hydraulic turbine subsystem of the mixed flow unit machinery as an example, its key components include: water guide bearings, main shaft seals, air supply systems, etc.

[0041] 5) The classification structure diagram of maintenance evaluation objects is shown in Figure 2 .

[0042] 3. Principles for selecting status evaluation items 1) The selection of status evaluation items should be able to directly and effectively reflect the operating status of relevant components and the trend and degree of component performance degradation.

[0043] 2) The selection of status evaluation items should be technically feasible, and the evaluation of status evaluation items should be supported by clear procedures and specifications.

[0044] 3) Status evaluation items should be refined as much as possible according to the functions of specific components and can be described based on the physical status of the components.

[0045] 4) Status evaluation items are the smallest units for equipment maintenance project evaluation.

[0046] 4. Obtaining status evaluation items 1) The information of status evaluation items comes from on-site inspection, historical data, operation data, test data, maintenance data and other data.

[0047] 2) On-site inspections should include but are not limited to manual visual inspections, special tool inspections, non-destructive testing inspections, and preventive testing inspections.

[0048] 3) Historical data should include but are not limited to: design and manufacturing data, ordering technical specifications, equipment nameplate parameters, equipment technical manuals, transportation records, type test reports, equipment supervision reports, factory test reports, installation and commissioning reports, handover test reports, performance test reports, installation and operating instructions, installation process quality control record cards (QCR), etc.

[0049] 4) Operation data include but are not limited to: real-time equipment operation data, online monitoring system (real-time and trend data such as unit vibration, fault waveform, pressure pulsation, etc.), operation logs, inspection records, historical defects and abnormality records, etc.

[0050] 5) Test data include but are not limited to: unit stability test report, targeted unit equipment specific test report, etc.

[0051] 6) Maintenance data include but are not limited to: equipment maintenance history and maintenance and change reports, equipment inspection and test reports, operation and maintenance and equipment special analysis reports, equipment technical transformation and major component replacement records, etc.

[0052] 7) Other information includes, but is not limited to: operation, maintenance tests, systemic defects and fault handling information and maintenance experience of similar equipment at home and abroad; description of the implementation of relevant countermeasures (if any); changes in operating conditions and environment; formulation and revision of national, industry and manufacturer standards, etc.

[0053] 8) The acquisition of status evaluation items should be feasible and should be combined with regulations and specifications, manufacturer's operation and maintenance manuals and actual operation and maintenance experience.

[0054] Step 2: Set weights based on the importance of the lower level to the performance and safe and reliable operation of the upper level.

[0055] Each level is divided into levels according to importance, and each level corresponds to a different weight.

[0056] 1. Weight of status evaluation items According to the importance of the status evaluation items to the performance and safe and reliable operation of the secondary components, they are divided into Level 1, Level 2, Level 3, Level 4, Level 5, Level 6, Level 7, Level 8, Level 9, and Level 10 from light to heavy, and their weights are 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 respectively, as shown in Table 1 below.

[0057] The weight values ​​of the status evaluation items of different types of hydro-generators / turbines / speed control systems / water inlet valves (components) should be set according to their own design, process, manufacturing, installation, materials, operation and maintenance, and can also be adjusted according to the actual situation on site.

[0058]

[0059] 2. Secondary component weight According to the importance of secondary components to the performance and safe and reliable operation of key components, they are divided into Level 1, Level 2, Level 3, Level 4, Level 5, Level 6, Level 7, Level 8, Level 9, and Level 10 from light to heavy, and their weights are 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 respectively, as shown in Table 2 below.

[0060]

[0061] 3. Key component weights The health of key components is a basic indicator that affects the performance and safe and reliable operation of each subsystem. The degradation of any key component will definitely affect the performance and safe and reliable operation of the entire subsystem. The importance of each component has the same impact on the subsystems, so no weight is defined for key components.

[0062] Step 3: Evaluate the performance degradation degree of the status evaluation items.

[0063] According to the degree of degradation of the status evaluation items, they are graded from light to heavy. Each level corresponds to a different basic deduction value, and the deduction rule is obtained. The status evaluation items are deducted according to the deduction rule to obtain the deduction value. y 0, the degradation deduction value is calculated according to the following formula y Used to characterize the degree of degradation: (1); in, x is the weight of the status evaluation item.

[0064] In this embodiment, the status evaluation items are divided into 10 levels from light to heavy according to the degree of degradation. They are level 1, level 2, level 3, level 4, level 5, level 6, level 7, level 8, level 9, and level 10, and the corresponding deduction values ​​are 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10, as shown in Table 3. The deduction value of the status evaluation item is related to the degree of degradation or defect itself. The deduction value of the status evaluation item is different according to the degree of degradation or defect. The deduction range is between [1, 10], with a maximum deduction of 10 points and a minimum deduction of 1 point. No deduction is required if there is no degradation phenomenon or defect.

[0065]

[0066] Deterioration deduction value of condition evaluation item (before / after repair): The deduction value of condition evaluation item (before / after repair) is determined by the condition evaluation item weight and the (before / after repair) deduction value (including the deduction value of system defects of the condition evaluation item), that is, the deduction value of the condition evaluation item is equal to the deduction value of the condition evaluation item multiplied by the weight of the condition evaluation item.

[0067] Step 4: Calculate the health of each status evaluation item through weight and degradation deduction value, and then calculate the health of the equipment at the corresponding level step by step.

[0068] Equipment health is an indicator for evaluating equipment reliability, including three levels: health of status evaluation items, health of secondary components, and health of key components. The health of secondary components is calculated by the health of status evaluation items and the weight of status evaluation items, and the health of key components is calculated by the health of secondary components and the weight of secondary components.

[0069] The health of the status evaluation item is calculated using the following formula: (2); In the formula, a Indicates the health of the status evaluation item, y Indicates the degradation penalty value of the status evaluation item.

[0070] Secondary component health Corresponding status evaluation item health a and the weight of the status evaluation item x The conversion relationship is calculated according to formula (3): (3); Where: Indicates the health of the status evaluation item in the lower level corresponding to the secondary component, Represents the weight of the status evaluation item in the lower level corresponding to the secondary component, n Indicates the number of status evaluation items in the lower level corresponding to the secondary component.

[0071] Key component health The health of the corresponding secondary components and secondary component weights The conversion relationship is calculated according to formula (4): (4); Where: Indicates the health of the secondary components in the lower level corresponding to the key components. Indicates the weight of the secondary component in the lower level corresponding to the key component. m Indicates the number of secondary components in the lower level corresponding to the key component.

[0072] Among them, 0% represents low health and 100% represents high health. The key status evaluation items are marked in the status evaluation items in the lower level corresponding to the secondary component, and are marked with "★". The health of the key status evaluation items determines the health of the secondary component.

[0073] The key status evaluation items are recorded as , if the secondary component health <Key status evaluation item health ,but: (5); If the secondary component health >Key status evaluation item health ,but: (6).

[0074] The key second-level components in the second-level components in the lower level corresponding to the key components are marked with "★". The health of the key second-level components determines the health of the key components.

[0075] The health of key secondary components is If the health of key components <Health of key secondary components ,but: (7); If the health of key components >Health of key secondary components ,but: (8).

[0076] Each subsystem is composed of multiple key components. The health of a single subsystem is determined by the health of the key components at the next level. The health of a subsystem is equal to the minimum health of the key components at the next level.

[0077] Evaluate the equipment status according to the calculated health level: divide the health level into intervals, and divide the health level from high to low into "normal state", "caution state", "abnormal state" and "dangerous state". Judge the equipment status according to the interval in which the calculated health level of the status evaluation item is located, see Table 4.

[0078]

[0079] In order to facilitate the intuitive and comprehensive comparison and display of the maintenance evaluation results, the evaluation health status of the components is identified and distinguished by four colors: "green, yellow, orange, and red", which represent the health status levels of the components such as "normal, caution, abnormal, and dangerous" respectively.

[0080] The evaluation criteria are classified as follows: When the health degree of any status evaluation item is in the range of [80%, 100%] specified in Table 4, it is considered as "normal state"; When the health level of any status evaluation item is in the range of [60%, 80%) specified in Table 4, it is considered as “caution status”; When the health degree of any status evaluation item is in the range of [40%, 60%) specified in Table 4, it is considered as an "abnormal state"; When the health level of any status evaluation item is in the range of [0%, 40%) specified in Table 4, it is considered as a "dangerous state"; The evaluation rule for judging the status of the device according to the interval where the health of the status evaluation item is located is: When all equipment status evaluation items are evaluated as "normal status", the overall equipment evaluation is "normal status"; When all status evaluation items corresponding to the second-level component are evaluated as "normal state", the second-level component is evaluated as "normal state"; When any status evaluation item of a secondary component is "caution status", "abnormal status" or "dangerous status", the secondary component is evaluated as the most serious status.

[0081] According to the final conclusion of the maintenance evaluation of the turbine generator / turbine / speed control system / water inlet valve system, corresponding measures should be taken according to the most serious condition and completed within the implementation period.

[0082] Step 5. According to steps 3 and 4, calculate the equipment health status of each level of the hydro-turbine generator set before and after maintenance, and then calculate the maintenance quality improvement rate. The higher the maintenance quality improvement rate, the better the maintenance effect.

[0083] The maintenance quality improvement rate, that is, the maintenance quality improvement rate, is the change in the health of the equipment before and after the maintenance. It is an important quantitative indicator that directly reflects the maintenance effect. It represents the maintenance results and benefits of the equipment. The maintenance quality improvement rate is expressed as a percentage.

[0084] The maintenance quality improvement rate includes four levels: maintenance quality improvement rate of status evaluation items, maintenance quality improvement rate of secondary components, maintenance quality improvement rate of key components, and maintenance quality improvement rate of subsystems. The expressions are as follows: 1) Repair quality improvement rate of status evaluation items The maintenance quality improvement rate of the status evaluation item Δ and the health degree of the status evaluation item before maintenance a 0 and the health of the status evaluation item after repair a The transformation relationship is calculated according to formula (9): Δ= a - a 0(9).

[0085] 2) Secondary component maintenance quality improvement rate Secondary component overhaul quality improvement rate Δ' and secondary component pre-repair health and the secondary component repair health The transformation relationship is calculated according to formula (10): (10).

[0086] 3) Quality improvement rate of key component maintenance Quality improvement rate of key component maintenance Health of key components before repair and the health of key components after repair The transformation relationship is calculated according to formula (11): (11).

[0087] 4) Subsystem maintenance quality improvement rate When a subsystem has multiple key components and corresponds to multiple key component health levels and key component maintenance quality improvement rates, the maintenance quality improvement rate of the subsystem can be calculated by the arithmetic mean of the maintenance quality improvement rates of each key component.

[0088] The effectiveness of equipment maintenance is directly related to the maintenance quality improvement rate. During the equipment maintenance process, if the degree of deterioration of the equipment status evaluation items is higher, the maintenance quality improvement rate after the equipment status evaluation items are repaired will be higher, indicating that the maintenance effectiveness is better.

[0089] According to the maintenance quality improvement rate, the equipment maintenance results are divided into four evaluation levels: "excellent, good, qualified, and unqualified". The corresponding relationship between equipment maintenance results and maintenance quality improvement rate is defined in the following table:

[0090] The equipment maintenance status evaluation is carried out in accordance with the principle of combining quantitative analysis with qualitative analysis, and maintenance strategies are formulated in a targeted manner based on the evaluation results. For those with clear standard limit requirements for characteristic status parameters, a quantitative evaluation method is adopted; for those without standard limit requirements, qualitative and quantitative evaluations should be conducted based on the equipment failure patterns and operation and maintenance experience. The equipment maintenance status evaluation is organized by the maintenance implementation unit and the equipment management unit. The purpose is to determine the health status of the equipment before and after maintenance through evaluation. It is divided into key component maintenance evaluation, equipment subsystem maintenance evaluation and equipment overall maintenance evaluation.

[0091] The equipment maintenance evaluation mainly focuses on the deterioration deduction value of the status evaluation item (before / after repair), the health of the status evaluation item (before / after repair), the health of the secondary components (before / after repair), the health of the key components (before / after repair), the maintenance quality improvement rate Δ of the status evaluation item, and the maintenance quality improvement rate of the secondary components. , Quality improvement rate of key component maintenance A comprehensive evaluation is conducted based on quantitative indicators such as the equipment quality and maintenance performance to ultimately draw conclusions on the equipment’s current health status and maintenance effectiveness.

[0092] The effectiveness of equipment maintenance is related to the maintenance quality improvement rate. The maintenance quality improvement rate from the unit level to the parts level is defined as follows: The maintenance quality improvement rate Δ of a single status evaluation item can be directly calculated by formula (9).

[0093] When a secondary component has n status evaluation items and corresponds to multiple status evaluation item health and maintenance quality improvement rate Δ, the maintenance quality improvement rate of the secondary component It can be directly calculated by formula (10); When a key component has n secondary components and corresponds to multiple secondary component health levels and overhaul quality improvement rates Δ, the secondary component overhaul quality improvement rate It can be directly calculated by formula (11); When a subsystem (generator, turbine, governor, cylinder valve) has n key components and corresponds to multiple key component health And key parts maintenance quality improvement rate When , the maintenance quality improvement rate Δ0 of the subsystem can be calculated by the arithmetic mean of the maintenance quality improvement rates of each key component.

[0094] Each subsystem is composed of multiple key components. The health of a single subsystem is determined by the health of its next-level key components. The health of a subsystem is equal to the minimum health of its next-level key components (i.e., the maximum degree of degradation).

[0095] The above-mentioned embodiments are only preferred technical solutions of the present invention and should not be regarded as limitations of the present invention. The protection scope of the present invention shall be the technical solutions recorded in the claims, including equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to list all the implementation methods here, that is, equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. A method for evaluating the quality of equipment maintenance of a hydro-generator set, characterized in that: The following steps are involved: Step 1: divide the hydro-generator units into levels until they are decomposed into the smallest maintenance unit or inspection item, which is called the status evaluation item; Step 2: Set weights based on the importance of the lower level to the performance and safe and reliable operation of the upper level; Step 3: Evaluate the performance degradation degree of the status evaluation items; Step 4: Calculate the health of each status evaluation item by weight and degradation deduction value, and then calculate the health of the equipment at the corresponding level step by step; Step 5. According to steps 3 and 4, calculate the equipment health status of each level of the hydro-turbine generator set before and after maintenance, and then calculate the maintenance quality improvement rate. The higher the maintenance quality improvement rate, the better the maintenance effect.

2. The equipment maintenance quality evaluation method for a hydro-generator set according to claim 1 is characterized in that: In the step 1, the hydro-generator set is decomposed in the order of "professional-subsystem-key component-secondary component-inspection item".

3. The equipment maintenance quality evaluation method for a hydro-generator set according to claim 1 is characterized in that: In the step 2, each level is divided into levels according to importance, and each level corresponds to a different weight.

4. The equipment maintenance quality evaluation method for a hydro-generator set according to claim 2 is characterized in that: In the step 3, the status evaluation items are graded from light to heavy according to the degree of degradation, and each level corresponds to a different basic deduction value, and a deduction rule is obtained. The status evaluation items are deducted according to the deduction rule to obtain the deduction value. y 0, the degradation deduction value is calculated according to the following formula y Used to characterize the degree of degradation: （1）； in, x is the weight of the status evaluation item.

5. The method for evaluating the equipment maintenance quality of a hydro-generator set according to claim 4, characterized in that: In step 4, the health of the status evaluation item is calculated using the following formula: （2）； In the formula, a Indicates the health of the status evaluation item, y Indicates the degradation penalty value of the status evaluation item.

6. The equipment maintenance quality evaluation method for a hydro-generator set according to claim 1 is characterized in that: In step 4, the health of the secondary component Corresponding status evaluation item health a and the weight of the status evaluation item x The conversion relationship is calculated according to formula (3): （3）； Where: Indicates the health of the status evaluation item in the lower level corresponding to the secondary component, Represents the weight of the status evaluation item in the lower level corresponding to the secondary component, n Indicates the number of status evaluation items in the lower level corresponding to the secondary component; Key component health The health of the corresponding secondary components and secondary component weights The conversion relationship is calculated according to formula (4): (4)； Where: Indicates the health of the secondary components in the lower level corresponding to the key components. Indicates the weight of the secondary component in the lower level corresponding to the key component. m Indicates the number of secondary components in the lower level corresponding to the key component.

7. A method for evaluating the quality of equipment maintenance of a hydro-generator set according to claim 6, characterized in that: The state evaluation items in the lower level corresponding to the secondary component are marked with key state evaluation items, and the key state evaluation items are recorded as , if the secondary component health <Key status evaluation item health ,but: (5)； If the secondary component health >Key status evaluation item health ,but: (6)； Mark the key second-level components in the lower-level components corresponding to the key components. The health of the key second-level components is If the health of key components <Health of key secondary components ,but: (7)； If the health of key components >Health of key secondary components ,but: (8)； Each subsystem is composed of multiple key components. The health of a single subsystem is determined by the health of the key components at the next level. The health of a subsystem is equal to the minimum health of the key components at the next level.

8. The method for evaluating the quality of equipment maintenance of a hydro-generator set according to claim 1, characterized in that: In the step 4, the equipment status is evaluated according to the calculated health level: the health level is divided into intervals, and the health level is divided into "normal state", "caution state", "abnormal state" and "dangerous state" from high to low, and the status of the equipment is judged according to the interval in which the health level of the calculated status evaluation item is located.

9. The method for evaluating the quality of equipment maintenance of a hydro-generator set according to claim 8, characterized in that: The evaluation rule for judging the state of the device according to the interval in which the health of the state evaluation item is located is: When all equipment status evaluation items are evaluated as "normal status", the overall equipment evaluation is "normal status"; When all status evaluation items corresponding to a secondary component are evaluated as "normal status", the secondary component is evaluated as "normal status"; When any status evaluation item of a secondary component is "caution status", "abnormal status" or "danger status", the secondary component is evaluated as the most serious status.

10. The method for evaluating the quality of equipment maintenance of a hydro-generator set according to claim 1, characterized in that: The maintenance quality improvement rate includes four levels: maintenance quality improvement rate of status evaluation items, maintenance quality improvement rate of secondary components, maintenance quality improvement rate of key components, and maintenance quality improvement rate of subsystems. The expressions are as follows: 1) Repair quality improvement rate of status evaluation items The maintenance quality improvement rate of the status evaluation item Δ and the health degree of the status evaluation item before maintenance a 0 and the health of the status evaluation item after repair a The transformation relationship is calculated according to formula (9): D= a - a 0 (9); 2) Secondary component maintenance quality improvement rate Secondary component overhaul quality improvement rate Δ' and secondary component pre-repair health and the secondary component repair health The transformation relationship is calculated according to formula (10): （10）； 3) Quality improvement rate of key component maintenance Quality improvement rate of key component maintenance Health of key components before repair and the health of key components after repair The transformation relationship is calculated according to formula (11): （11）； 4) Subsystem maintenance quality improvement rate When a subsystem has multiple key components and corresponds to multiple key component health levels and key component maintenance quality improvement rates, the maintenance quality improvement rate of the subsystem can be calculated by the arithmetic mean of the maintenance quality improvement rates of each key component.

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