Highway electromechanical system preventive maintenance method and system based on device distribution

Abstract

The application provides a highway electromechanical system preventive maintenance method and system based on equipment distribution. The failure rate model of the electromechanical system equipment is constructed according to the correlation between each equipment, the equipment maintenance cost model is constructed by the highway maintenance mobile distance cost, the equipment leasing cost and the equipment field maintenance cost, the highway electromechanical system preventive maintenance cost optimization model is constructed by comprehensively considering the equipment failure rate model, the equipment maintenance cost model and other costs such as detection cost, the optimization model based on the system failure state is established under the system reliability constraint with the minimum system preventive maintenance total cost as the objective function, and the highway electromechanical equipment preventive maintenance strategy is solved. The application can fully consider the operation and maintenance cost change caused by the topological structure of the highway operation and maintenance object when the highway electromechanical system is maintained and managed, and then research the preventive joint maintenance strategy optimization from the perspective of large-scale system.

Description

Technical Field

[0001] This application relates to the field of intelligent highway systems, and more specifically to a preventive maintenance method and system for highway electromechanical systems based on equipment distribution. Background Technology

[0002] With the development of intelligent and information-based highways, the operation and maintenance of highway electromechanical systems has received increasing attention. Highway electromechanical systems consist of various subsystems such as power supply and distribution, communication, monitoring, toll collection, and tunnel electromechanical systems. These systems involve a large number of diverse devices, and there are interrelationships between them. For example, the normal operation of monitoring, toll collection, and tunnel electromechanical equipment depends on the reliable support of power supply and distribution and communication systems. Different devices also play different roles in ensuring the reliable operation of highways. Furthermore, highway electromechanical equipment is generally distributed along the highway, requiring maintenance work to be carried out over long distances. Therefore, optimizing preventative maintenance strategies for highway electromechanical systems with these characteristics, while ensuring reliable highway operation and reducing maintenance costs, is an urgent problem to be solved.

[0003] In terms of optimizing preventive maintenance decisions for highway electromechanical systems, most existing technologies do not consider the changes in maintenance costs caused by the topology of highway maintenance objects, and fail to conduct research on the optimization of preventive joint maintenance strategies from the perspective of large-scale systems. Summary of the Invention

[0004] This application addresses the shortcomings of existing technologies by providing a preventive maintenance method and system for highway electromechanical systems based on equipment distribution. This application focuses on preventive joint maintenance of highway electromechanical systems, constructing optimization models for the interrelationships between highway equipment, the impact of the topological characteristics of highway electromechanical equipment locations on operation and maintenance costs, and the preventive maintenance mode of multiple devices in the highway electromechanical system. This provides preventive joint maintenance strategies from the perspective of large-scale systems. The specific technical solutions adopted in this application are as follows.

[0005] First, to achieve the above objectives, a preventive maintenance method for highway electromechanical systems based on equipment distribution is proposed. The steps include: pre-setting specific parameters in the failure rate model, equipment maintenance cost model, and preventive maintenance cost optimization model of the electromechanical system equipment based on the interrelationships and topological characteristics between the various devices in the highway electromechanical system; and, based on the failure rate model of the electromechanical system equipment, calculating the failure rate function λ for each device, considering the interrelationships between the series and parallel connections of the highway equipment. ni(t), and then, based on the series and parallel relationships of the devices in the entire system, further calculate the quasi-joint pre-maintenance times for the entire system. Then, using the lower limit of system reliability as a constraint, substitute the failure rate of the entire system into the reliability assessment formula to calculate the system reliability constraint function. Substitute the actual progress of system pre-maintenance into the system reliability constraint function to form a pre-maintenance strategy offline. Based on the equipment maintenance cost model, calculate the moving distance cost L according to the road segment displacement between the equipment and the previous maintenance point. nm The equipment rental cost Z is calculated based on whether the equipment needs to be rented for maintenance during the equipment repair process. nm Then, based on the cost L of the travel distance. nm Equipment rental cost Z nm And the on-site maintenance cost of the equipment Q nm Calculate the pre-maintenance cost C for each device together. pnm =L nm +Z nm +Q nm Based on the cost optimization model for preventive maintenance of electromechanical systems, the total cost of system pre-maintenance, C, is used. w(sys) Using minimization as the objective function, and under reliability constraints, an optimization model based on the system failure state is established, combined with the preventive maintenance mode of multi-equipment joint operation in highway electromechanical systems. This model determines the system's detection and maintenance requirements. Based on the system's field maintenance and detection data, and according to the aforementioned failure rate model, equipment maintenance cost model, and preventive maintenance cost optimization model for electromechanical system equipment, a pre-maintenance strategy is proposed, with the pre-maintenance cost C for each piece of equipment. pnm =L nm +Z nm +Q nm And the system's testing and maintenance requirements.

[0006] Optionally, in the preventive maintenance method for highway electromechanical systems based on equipment distribution as described above, the failure rate model of the electromechanical system equipment includes the failure rate function of the nth type of equipment at time t. Among them, t i-l ρ is the time for the (il)th preventive maintenance of the nth type of equipment. n Let i be the improvement factor for the nth type of equipment, and i = 1, 2, ... represent the number of preventive maintenance operations.

[0007] Optionally, in any of the above-described preventive maintenance methods for highway electromechanical systems based on equipment distribution, the step of further calculating the number of quasi-joint pre-maintenance operations for the entire system based on the series and parallel connections of the equipment in the electromechanical system failure rate model includes: calculating the system failure rate when equipment is connected in parallel. The system failure rate when computing devices are connected in series is Based on the series and parallel connections of the devices in the entire system, the total number of quasi-joint pre-maintenance operations for the entire system is then calculated. Among them, h nm Let represent the number of pre-maintenance operations performed by the m-th device of the n-th class before time t, and let i represent the total number of quasi-joint pre-maintenance operations for the entire system.

[0008] Optionally, in any of the above-described preventive maintenance methods for highway electromechanical systems based on equipment distribution, the specific steps for calculating the system reliability constraint function in the failure rate model of the electromechanical system equipment include: using the lower limit of system reliability as a constraint, substituting the number of quasi-joint pre-maintenance cycles of the entire system into the reliability assessment formula, setting the critical value of the lower limit of system reliability to R0, indicating that the system reliability must not be less than R0 in the i-th preventive quasi-joint maintenance cycle, and obtaining the system reliability constraint function as follows: Among them, the failure shape parameter x corresponds to different types of equipment n. n different, Let nm[t0,t] be the operating time of the m-th device in the n-th class after the last component replacement. i [] represents the number of pre-maintenance operations performed on the m-th equipment of the n-th type within the i-th preventive quasi-joint maintenance cycle of the system. For the nth type and mth device, the (nm[t0,t)th) i The time for preventive maintenance is 1-1) if the m-th piece of equipment of type n is at t i If no component replacement was performed before the specified time, then t0 = 0; if a component replacement was performed, then t0 = t. nm , t nm This represents the most recent replacement time of the component of the m-th device in the n-th class.

[0009] Optionally, in any of the above-described preventive maintenance methods for highway electromechanical systems based on equipment distribution, the cost of travel distance is calculated in the equipment maintenance cost model. in, Let be the distance between the m-th device of the n-th class and the repair point of the h-th device of the previous k-th class, and let a be the cost per kilometer of distance.

[0010] Optionally, in any of the above-described preventive maintenance methods for highway electromechanical systems based on equipment distribution, the equipment maintenance cost model calculates the equipment rental cost Z. nm =z n / m, where z n =b n c n b n To determine whether pre-repair of equipment of type n requires the rental of repair equipment, take the value 0 or 1, cn The cost of renting maintenance equipment for one day for the pre-maintenance of equipment of type n, where m represents the number of equipment to be maintained.

[0011] Optionally, as described above, in the preventive maintenance method for highway electromechanical systems based on equipment distribution, the total pre-maintenance cost C in the preventive maintenance cost optimization model for the electromechanical system is... w(sys) ,in, This represents the expected maintenance cost between two replacements of the j-th device of the i-th type.

[0012] Furthermore, to achieve the above objectives, this application also provides a preventive maintenance system for highway electromechanical systems based on the method described in any of the preceding claims, comprising: a failure rate model for electromechanical system equipment, which calculates the failure rate function λ of each piece of equipment based on the correlation and influence relationships between series and parallel connections of various pieces of equipment in the highway. ni (t), and then, based on the series and parallel relationships of each device in the entire system, further calculate the quasi-joint pre-maintenance times of the entire system. Then, using the lower limit of system reliability as a constraint, substitute the failure rate of the entire system into the reliability assessment formula to calculate the system reliability constraint function. Substitute the actual progress of system pre-maintenance into the system reliability constraint function to form a pre-maintenance strategy offline; the equipment maintenance cost model, which addresses the impact of the topological characteristics of highway electromechanical equipment locations on operation and maintenance costs, calculates the moving distance cost L based on the road segment displacement between the equipment and the previous maintenance point. nm The equipment rental cost Z is calculated based on whether the equipment needs to be rented for maintenance during the equipment repair process. nm Based on the cost of travel distance L nm Equipment rental cost Z nm And the on-site maintenance cost of the equipment Q nm Calculate the pre-maintenance cost C for each device together. pnm =L nm +Z nm +Q nm The preventive maintenance cost optimization model for electromechanical systems uses the total pre-maintenance cost C of the system as its criterion. w(sys) Minimize the objective function. Under reliability constraints, considering the preventive maintenance mode of multiple devices in the highway electromechanical system, an optimization model based on system failure states is established to determine the system's detection and maintenance requirements. An interactive unit receives on-site maintenance and detection data from the system and, based on the aforementioned failure rate model, equipment maintenance cost model, and preventive maintenance cost optimization model of the electromechanical system, suggests pre-maintenance strategies. The pre-maintenance cost C for each device is... pnm =L nm +Z nm +Q nm And the system's testing and maintenance requirements.

[0013] Optionally, in any of the above-mentioned highway electromechanical system preventive maintenance systems, the specific parameters in the failure rate model, equipment maintenance cost model, and electromechanical system preventive maintenance cost optimization model of the above-mentioned electromechanical system equipment are preset according to the correlation and topological characteristics between the various equipment of the highway electromechanical system.

[0014] Beneficial effects

[0015] This application provides a preventive maintenance method and system for highway electromechanical systems based on equipment distribution. It can construct a failure rate model of the electromechanical system equipment based on the correlation and topological characteristics between the equipment, and calculate the pre-maintenance strategy by substituting the actual progress of pre-maintenance into the system reliability constraint function used in the model; simultaneously, it calculates the pre-maintenance strategy based on the travel distance cost L. nm Equipment rental cost Z nm And the on-site maintenance cost of the equipment Q nm A joint equipment maintenance cost model is constructed to calculate the pre-maintenance cost of each piece of equipment; and an optimization model based on system failure states is established according to the preventive maintenance mode of multiple equipment in the system to determine the system's detection and maintenance requirements. The system in this application can fully consider the changes in maintenance costs caused by the topology of highway maintenance objects when managing the maintenance of highway electromechanical systems through the above model, and thus conduct research on the optimization of preventive joint maintenance strategies from the perspective of large-scale systems.

[0016] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing this application. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present application and form part of the specification. Together with the embodiments of the present application, they serve to explain the present application but do not constitute a limitation thereof. In the drawings:

[0018] Figure 1 This is a schematic diagram of the maintenance point topology structure targeted in the system processing of this application. Detailed Implementation

[0019] To make the objectives and technical solutions of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the described embodiments of this application without creative effort are within the scope of protection of this application.

[0020] Those skilled in the art will understand that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0021] This application provides a preventive maintenance system for highway electromechanical systems based on equipment distribution, comprising:

[0022] The failure rate model for electromechanical system equipment calculates the failure rate function λ for each piece of equipment, taking into account the interconnected effects between series and parallel connections of various equipment in a highway. ni (t), and then, based on the series and parallel relationships of each device in the whole system, further calculate the number of quasi-joint pre-maintenance times for the whole system. Then, using the lower limit of system reliability as a constraint, substitute the failure rate of the whole system into the reliability evaluation formula to calculate the system reliability constraint function. Substitute the actual process of system pre-maintenance into the system reliability constraint function to form a pre-maintenance strategy offline.

[0023] The equipment maintenance cost model addresses the impact of topological characteristics of highway electromechanical equipment locations on operation and maintenance costs, calculating the relocation distance cost L based on the road segment displacement between the equipment and the previous maintenance point. nm The equipment rental cost Z is calculated based on whether the equipment needs to be rented for maintenance during the equipment repair process. nm Based on the cost of travel distance L nm Equipment rental cost Z nm And the on-site maintenance cost of the equipment Q nm Calculate the pre-maintenance cost C for each device together. pnm =L nm +Z nm +Q nm ;

[0024] The preventive maintenance cost optimization model for electromechanical systems uses the total pre-maintenance cost C of the system as its metric. w(sys) With the minimum as the objective function, under reliability constraints, considering the preventive maintenance mode of multiple devices in the electromechanical system of highways, an optimization model based on the system failure state is established to determine the system's detection and maintenance requirements.

[0025] The interactive unit receives on-site maintenance and testing data from the system. Based on the failure rate model, equipment maintenance cost model, and preventive maintenance cost optimization model of the electromechanical system equipment, it suggests pre-maintenance strategies, with a pre-maintenance cost C for each piece of equipment. pnm =L nm +Znm +Q nm And the system's testing and maintenance requirements.

[0026] Therefore, this application simplifies the unit degradation process into a continuous stochastic process through a failure rate model, and uses the Weibull distribution to describe this stochastic process. During the system operation phase, let the initial failure rate of the nth type of equipment be λ. n0 The instantaneous failure rate before pre-maintenance after a period of operation is λ. n1 The instantaneous failure rate after equipment pre-maintenance is λ n2 The relationship is λ n0 <λ n2 <λ n1 When a replacement part operation occurs, λ n0 =λ n2 The equipment failure rate has been restored to its initial level.

[0027] When the equipment failure follows a Weibull distribution, the failure distribution expression is:

[0028]

[0029]

[0030] f n (t) is the failure probability density function of the nth type of equipment.

[0031] Let ρ n Let be the improvement factor for the nth type of equipment. Then, the instantaneous failure rate at time t after a preventive maintenance can be expressed as:

[0032] λ n1 (t)=λ n (t-ρ n ·t1),t1≤t≤t2

[0033] Then, after the i-th (i = 1, 2, ...) preventive maintenance, the general form of the failure rate function of the n-th type of equipment at time t is:

[0034]

[0035] Where t i-l The time for the (il)th preventive maintenance of the nth type of equipment.

[0036] The electromechanical system of a highway consists of various subsystems, including power supply and distribution electronics, communication, monitoring, and toll collection. Each subsystem has a different function and different relationships with other subsystems. For example, failure of the power supply and distribution electronics or some equipment may lead to the failure of other subsystems or even the entire electromechanical system. Furthermore, similar interrelationships exist between equipment within each subsystem. Overall, the subsystems and their equipment can be abstracted into a series and parallel composite relationship. Therefore, when calculating failure rates, series and parallel failure rate calculation methods should be used based on the relationships between the equipment.

[0037] System failure rate when devices are connected in parallel:

[0038] System failure rate when devices are connected in series:

[0039] Based on the above failure rate calculation model, it can be seen that the failure rate λ of each device in the entire system can be calculated. ni (t) After that, based on the series and parallel connections of the devices in the entire system, the failure rate of the entire system is further calculated, where h nm Let be the number of pre-maintenance cycles performed by the m-th device of the n-th class before time t, and let i represent the total number of quasi-joint pre-maintenance cycles for the entire system.

[0040]

[0041] Using the lower limit of system reliability as a constraint, substituting the system failure rate model in the above formula into the reliability assessment formula, and setting the critical value of the lower limit of system reliability as R0, indicating that the system reliability must not be less than R0 in the i-th preventive quasi-joint maintenance cycle, the system reliability constraint function can be obtained as follows (taking a series system as an example):

[0042]

[0043] In the above formula, the failure shape parameter x corresponds to different types of equipment n. n different, Let nm[t0,t] be the operating time of the m-th device in the n-th class after the last component replacement. i [] indicates the number of pre-maintenances (after component replacement) performed on the nth type and mth equipment within the i-th preventive quasi-joint maintenance cycle of the system. For the nth type and mth device, the (nm[t0,t)th) i The time for preventive maintenance is 1-1) if the m-th piece of equipment of type n is at t i If no component replacement was performed before the specified time, then t0 = 0; if a component replacement was performed, then t0 = t. nm , t nmThis represents the most recent replacement time of the component of the m-th device in the n-th category. Because the pre-maintenance strategy is formed offline, it is continuously modified during the pre-maintenance execution process based on the actual progress of the system's pre-maintenance.

[0044] In addition, the system of this application can also divide the overall maintenance cost of the system into three categories based on the characteristics of highway operation and maintenance, through the equipment maintenance cost model: travel distance cost, equipment rental cost, and on-site maintenance cost (including material cost, labor cost, etc.).

[0045] Therefore, the pre-maintenance cost of a single device is calculated as follows:

[0046] C pnm =L nm +Z nm +Q nm

[0047]

[0048] Where L nm Z represents the travel distance cost of the m-th device in the n-th class. nm Let Q be the maintenance equipment rental cost for the m-th device in the n-th category. nm Let be the on-site maintenance cost of the m-th device in the n-th category.

[0049] set up Let 'a' represent the distance between the m-th device of type n and the previous repair point (the h-th device of type k), and 'a' represent the cost per kilometer. Using the following repair point topology as an example, circles represent repair points, and the numbers inside represent the device type and its corresponding number; the lines connecting the circles represent the cost of moving between devices.

[0050] refer to Figure 1 Assuming that the principle of minimum distance is followed when pre-maintenance operations move between different devices, the movement cost matrix corresponding to the above topology can be obtained as follows.

[0051]

[0052] In the moving cost matrix G, the rows and columns are composed of equipment numbers, as follows:

[0053]

[0054] The element L(i,j) represents the distance cost between the i-th device and the j-th device in the system.

[0055] Taking the above topology as an example, if starting from the first device (L) 11 Departing from the third device (L) 21 Pre-maintenance was carried out on the fourth piece of equipment (L).22 If pre-repair is performed and then the travel distance is returned to the starting point, the cost of the travel distance is: g 13 +g 34 +g 41 .

[0056]

[0057] In the calculation of equipment leasing costs, z n =b n c n b n To determine whether pre-repair of equipment of type n requires the rental of repair equipment, take the value 0 or 1, c n This is the cost of renting maintenance equipment for one day for pre-maintenance of equipment of type n. Assuming each pre-maintenance is completed within one day, and each piece of equipment can only be pre-maintained once per session, the equipment rental cost is the one-day rental fee divided by the number of pieces of equipment to be repaired.

[0058] Z nm =z n / m

[0059] The total time t spent on all equipment repairs within a day (including equipment repair time and road travel time) should be less than 8 hours.

[0060]

[0061] Among them, t nm T represents the on-site maintenance time for the m-th device in the n-th category. i This represents the travel time of road segment i during the maintenance process.

[0062] Furthermore, the system of this application can also be optimized using a pre-maintenance cost model for electromechanical systems, where c wij T represents the average unit maintenance cost of the j-th device of type i within a unit of time. ij Let C be the expected time between two replacements of the j-th device of the i-th class. wij To obtain the expected total maintenance cost between two replacements of the j-th device of the i-th type, we have:

[0063]

[0064] Since the equipment status can only be determined through inspection, and faults are immediately addressed by replacement, the expected time T between two unit replacements is as follows: ij It can be represented as:

[0065]

[0066] in, The number of inspections between two replacements is given, and h represents the number of preventive quasi-joint maintenance procedures performed on the j-th equipment of type i during the l-th inspection. Let f(i) represent the failure probability density function of the i-th type of equipment after h pre-maintenance cycles.

[0067] The expected maintenance cost for the j-th device in the i-th category includes: replacement cost C rij Detection cost C hij Preventive joint maintenance cost C pij and downtime penalty cost C bij Then, the expected total maintenance cost C between two replacements of the j-th device of the i-th type is... wij for:

[0068]

[0069] Further, we can conclude that:

[0070]

[0071] Therefore, the total cost of system pre-maintenance is C. w(sys) Minimize the objective function. Under system reliability constraints, the optimization model based on system failure states can be expressed as:

[0072]

[0073] stR i (t i )≥R0

[0074] Therefore, based on the system's on-site maintenance and testing data, and according to the aforementioned failure rate model, equipment maintenance cost model, and electromechanical system preventive maintenance cost optimization model, the system can suggest pre-maintenance strategies, with a pre-maintenance cost C for each piece of equipment. pnm =L nm +Z nm +Q nm This includes the system's testing and maintenance requirements. The specific steps are as follows:

[0075] 1) The Weibull distribution is used to describe the failure rate model of the electromechanical system equipment of highways. For the electromechanical system of highways, the failure rate calculation method is carried out by series and parallel connection according to the relationship between the equipment contained in different subsystems such as power supply and distribution electronic system, communication subsystem, monitoring subsystem, and toll collection subsystem.

[0076] 2) Based on the highway electromechanical equipment maintenance cost model, calculate the equipment maintenance cost, which consists of travel distance cost, maintenance equipment rental cost, and on-site maintenance cost. The total time spent on equipment maintenance within a day (including equipment maintenance time and road segment travel time) must be less than 8 hours.

[0077] 3) Combining the above equipment failure rate model and equipment maintenance cost model, and taking into account replacement cost, inspection cost, and downtime penalty cost, a pre-maintenance cost optimization model for electromechanical systems is constructed.

[0078] 4) Taking the minimum total cost of system pre-maintenance as the objective function, and under system reliability constraints, an optimization model based on system failure states is established, and the equipment pre-maintenance strategy is further solved. The above is merely an implementation method of this application, and its description is relatively specific and detailed, but it should not be construed as limiting the scope of this application's patent. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application.

Claims

1. A method for preventive maintenance of a highway electromechanical system based on equipment distribution, characterized by the steps of The application relates to a method for optimizing the preventive maintenance cost of a mechanical and electrical system of a highway, comprising the following steps: In the failure rate model of the mechanical and electrical system device, according to the series and parallel relationship of the devices in the whole system, the step of further calculating the quasi-joint preventive maintenance frequency of the whole system comprises the following steps: According to the failure rate model of the electromechanical system equipment, the failure rate function of each equipment is calculated respectively according to the associated influence relationship corresponding to the series and parallel connection of each equipment on the highway Then, the quasi joint preventive maintenance frequency of the whole system is calculated according to the series and parallel connection relationship of each equipment in the whole system, the system reliability constraint function is calculated by taking the failure rate of the whole system into the reliability evaluation formula with the lower limit of the system reliability as the constraint, and the preventive maintenance strategy is formed offline by taking the actual process of the system preventive maintenance into the system reliability constraint function. According to the equipment maintenance cost model, the moving distance cost is calculated according to the displacement of the road section between the equipment and the last maintenance point , the equipment rental cost is calculated according to whether the maintenance equipment needs to be rented during the equipment maintenance process , and then the pre-maintenance cost of each equipment is calculated according to the moving distance cost , the equipment rental cost , and the on-site maintenance cost of the equipment ;​ According to the electromechanical system preventive maintenance cost optimization model, the system preventive maintenance total cost The minimum is the objective function, under the reliability constraint, combined with the preventive maintenance mode of multiple devices of the electromechanical system of the expressway, the optimization model based on the system failure state is established, and the detection requirement and maintenance requirement of the system are determined; According to the field maintenance data and detection data of the system, the failure rate model, the equipment maintenance cost model and the mechanical and electrical system preventive maintenance cost optimization model of the mechanical and electrical system equipment are used to prompt the preventive maintenance strategy, and the preventive maintenance cost of each equipment and the detection requirements and maintenance requirements of the system; In the failure rate model of the electromechanical system equipment. Time of the first Failure rate function of device class ,in, For the first Class of equipment The time required for preventative maintenance. For the first Improvement factors for similar equipment Indicates the number of preventative maintenance procedures; In the failure rate model of the mechanical and electrical system device, the specific step of calculating the system reliability constraint function comprises the following steps: The system failure rate when computing devices are connected in parallel is The system failure rate when computing devices are connected in series is Then, based on the series and parallel connections of the devices in the entire system, the total number of quasi-joint pre-maintenance operations for the entire system is further calculated. ,in, For the first Class 1 The device is Number of pre-maintenance cycles up to a given time. This indicates the total number of quasi-joint pre-maintenance operations for the entire system; The application relates to a method for optimizing the preventive maintenance cost of a mechanical and electrical system of a highway, comprising the following steps: The lower limit of system reliability is taken as a constraint, and the quasi-joint preventive maintenance times of the whole system are substituted into the reliability evaluation formula. The critical value of the lower limit of system reliability is set as , which means that the reliability of the system must be not less than in the th preventive quasi-joint maintenance cycle. The system reliability constraint function is obtained as follows: wherein the different types of devices corresponding failure shape parameters different, is the first is the first is the running time of the first indicates the first is the number of preventive maintenance of the first is the first is the time of the first is the time of the first is the first is the time of the first if the first is the first is the time before which the first if there is a component replacement, then if there is no component replacement, then , is the time of the last replacement of the first is the first is the first In the equipment maintenance cost model, the cost of the travel distance is calculated. ,in, For the first Class 1 The device is the same as the previous one. Class 1 The distance between the repair points of each piece of equipment Cost per kilometer; The device repair cost model calculates the device rental cost wherein, , is the device rental cost for the nth class device repair, and is the device rental cost for the nth class device repair, and m represents the number of devices being repaired.

2. A preventive maintenance system for a highway electromechanical system based on the method of claim 1, characterized by The specific parameters in the failure rate model of the mechanical and electrical system device, the device maintenance cost model and the mechanical and electrical system preventive maintenance cost optimization model are preset according to the association and topological characteristics of the devices in the mechanical and electrical system of the highway. The failure rate model of the mechatronic system device calculates the failure rate function of each device according to the associated influence relationship between the devices in series and in parallel According to the series and parallel relationship of each device in the whole system, the quasi joint preventive maintenance frequency of the whole system is further calculated, then the failure rate of the whole system is brought into the reliability evaluation formula to calculate the system reliability constraint function, and the system reliability constraint function is brought into the actual process of the system preventive maintenance to form the preventive maintenance strategy offline. A device maintenance cost model, which calculates the moving distance cost according to the displacement of the road section between the device and the last maintenance point , calculates the device rental cost according to whether the device needs to be rented during maintenance , and calculates the pre-maintenance cost of each device according to the moving distance cost , the device rental cost and the on-site maintenance cost of the device ; An electromechanical system preventive maintenance cost optimization model, which takes the total system preventive maintenance cost The minimum as the objective function, under the reliability constraint, considering the joint preventive maintenance mode of multiple devices of the electromechanical system of the expressway, an optimization model based on the system failure state is established to determine the detection requirements and maintenance requirements of the system; An interaction unit receives the field maintenance data and the detection data of the system, and prompts a preventive maintenance strategy according to the failure rate model, the equipment maintenance cost model and the electromechanical system preventive maintenance cost optimization model of the electromechanical system equipment, the preventive maintenance cost of each equipment , and the detection requirement and the maintenance requirement of the system.

3. The highway electro-mechanical system preventive maintenance system of claim 2, wherein, ​

Images