An ac-dc fusion power distribution network system and an intelligent operation and maintenance method thereof

Abstract

The application discloses a kind of alternating current-dc fusion distribution network system and its intelligent operation and maintenance method, wherein, alternating current-dc fusion distribution network system includes: using radial topology structure alternating current distribution network and using grid topology structure direct current distribution network, the alternating current distribution network and direct current distribution network respectively in power supply side and load side through inverter energy exchange, alternating current and direct current distribution line is isolated with power supply and load by circuit breaker, and under fault condition, alternating current distribution network is through direct current distribution network loop operation, uninterrupted power supply.Inventive embodiment proposed alternating current-dc fusion distribution network system has the characteristics of fast control speed, long-distance transmission efficiency, without the original alternating current line distribution network modification capacity, make full use of the transmission capacity of existing equipment, quickly respond when fault occurs, effectively combine distribution main equipment, under the premise of relay protection device action, without affecting the normal power supply of load, can effectively improve power supply reliability.

Description

Technical Field

[0001] This invention belongs to the field of power distribution network technology, specifically relating to an AC / DC integrated power distribution network system and its intelligent operation and maintenance method. Background Technology

[0002] In current power distribution networks, AC distribution networks remain the mainstream form, as they are more suitable for AC distributed power generation. However, connecting DC distributed power sources and energy storage units requires power electronic devices for energy conversion, increasing the number of energy conversions, investment costs, and reducing efficiency. With the continuous increase in DC loads, research on DC distribution networks has developed rapidly. Compared with traditional AC distribution networks, DC distribution networks have advantages such as fewer conversions, higher efficiency, lower cost, simpler control structure, and no need to consider frequency, phase, or reactive power compensation equipment.

[0003] Despite the unique advantages of DC distribution networks, they are unlikely to replace AC distribution networks due to the well-established infrastructure and the long-term presence of AC power sources and loads. Furthermore, the existing transmission capacity of AC distribution networks is insufficient to meet the future demands of large-scale DC loads and power sources. In addition, the high cost of voltage level conversion between high-voltage, high-capacity DC transmission networks and low-voltage DC distribution networks necessitates energy conversion between small-scale DC distribution networks and AC distribution networks via AC / DC and DC / AC converters, and connection to the high-voltage, high-capacity AC backbone transmission network via AC transformers—a hybrid AC / DC distribution network structure. In a hybrid AC / DC distribution network, new AC and DC loads can be connected to AC and DC buses respectively, reducing energy conversion steps, lowering costs, and making it easier for AC and DC loads to connect to the system. Therefore, hybrid AC / DC distribution networks represent the future trend of distribution network development.

[0004] In AC distribution networks, the power supply to DC loads requires energy conversion via AC / DC converters. Furthermore, in traditional AC distribution networks, after a fault occurs, power is first cut off to isolate the fault before power is restored. The time required for fault diagnosis, fault isolation, and load transfer is relatively long, resulting in low power supply reliability. In addition, AC distribution networks suffer from various types of power quality problems, such as voltage fluctuations, frequency variations, and grid harmonics, all of which can significantly impact user power quality, and comprehensive remediation is costly. In DC distribution networks, the power supply to AC loads requires energy exchange via DC / AC converters. DC distribution networks suffer from power quality problems such as complex circuit breaker structures, high energy losses during AC-DC conversion, poor controllability and flexibility, poor bidirectional interaction, poor support for new energy sources, and voltage fluctuations. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an AC / DC integrated distribution network system and its intelligent operation and maintenance method to improve power supply reliability.

[0006] To address the aforementioned technical problems, this invention provides an AC / DC integrated distribution network system, comprising: an AC distribution network with a radial topology and a DC distribution network with a grid topology. The AC and DC distribution networks exchange energy on the power supply side and the load side, respectively, through inverters. The AC and DC distribution lines are isolated from the power supply and load through circuit breakers. Under fault conditions, the AC distribution network operates in a closed loop through the DC distribution network to provide uninterrupted power supply.

[0007] Furthermore, each transformer substation consists of an AC distribution line and a corresponding DC distribution line. The AC distribution line 1 and AC distribution line n have the same voltage level, and the DC distribution line 1 and DC distribution line n have the same voltage level, where n is a natural number greater than 1.

[0008] Furthermore, when transformer 1 fails, it is disconnected by the circuit breaker, and the system supplies power to the load through DC power supply 1, DC power supply n, and transformer n; when DC power supply 1 fails, the load is supplied by DC power supply n, transformer 1, and transformer n.

[0009] This invention also provides an intelligent operation and maintenance method for an AC / DC integrated distribution network system, comprising:

[0010] Step S1: Perform a status evaluation on the main power distribution equipment based on edge computing to determine the status evaluation level of the main power distribution equipment;

[0011] Step S2: Assess the likelihood and severity of the consequences of a failure in the main power distribution equipment, calculate the risk value of the main power distribution equipment, conduct a failure risk assessment based on the risk value, and determine the risk level.

[0012] Step S3: Based on the determined risk level, classify the main power distribution equipment into corresponding categories and construct the AC / DC integrated power grid operation and maintenance strategy for each category;

[0013] Step S4: Based on the status evaluation level of the main power distribution equipment, obtain the fault type and fault location of the main power distribution equipment, and establish a corresponding AC / DC integrated power grid fault operation and maintenance strategy.

[0014] Step S5: Based on the AC / DC integrated power grid planned operation and maintenance strategy and the DC integrated power grid fault operation and maintenance strategy, obtain the intelligent operation and maintenance strategy of the AC / DC integrated distribution network system.

[0015] Furthermore, step S1 specifically includes: digitizing the status information of the main power distribution equipment, establishing the relationship between fault types and status quantities, and determining the weights of the status quantities.

[0016] Furthermore, the digitization of the status information of the main power distribution equipment specifically involves: using the fault tree method to revise the defect standard library so that the defect standard library corresponds one-to-one with the evaluation items, then determining the deduction and weight of the status quantities, and establishing a standard status evaluation model for the main power distribution equipment.

[0017] The specific method for establishing the relationship between fault type and state variable is as follows: using the fault-Bayesian network method, the relationship between fault type and state variable is obtained by deriving the fault probability.

[0018] The specific method for determining the weights of the state variables is to use rough set theory to calculate the weights of the state variables.

[0019] Furthermore, step S3 divides the main power distribution equipment into four categories based on equipment risk: Category I, Category II, Category III, and Category IV; the operation and maintenance content includes four major categories: inspection, maintenance, testing, and overhaul.

[0020] Furthermore, the specific operation and maintenance strategies for constructing each type of AC / DC integrated power grid plan include: focusing on strengthening the operation and maintenance of Class I and Class II equipment and shortening their operation and maintenance cycles. For Class III and Class IV equipment, their operation and maintenance cycles will be appropriately extended, but the longest cycle shall not exceed the minimum standard.

[0021] Furthermore, in step S4, the AC / DC integrated power grid planned fault operation and maintenance strategy is an emergency power transfer strategy formulated for equipment that has already failed.

[0022] Furthermore, the emergency power transfer strategy includes the following aspects:

[0023] When AC line 1 fails, the line is disconnected by the circuit breaker, and the system can supply power to the load through DC distribution line 1, DC distribution line n and AC distribution line n; similarly, when any one DC distribution line fails, the other three lines can provide reliable power.

[0024] When transformer 1 fails, it is disconnected by the circuit breaker, and the system can supply power to the load through DC power supply 1, DC power supply n and transformer n; similarly, when DC power supply 1 fails, the load can be supplied by DC power supply n, transformer 1 and transformer n.

[0025] When the inverter on the transformer 1 and DC power supply 1 side fails, the inverter is disconnected by the circuit breaker, and the system can supply power to AC load 1 through other inverters on the power supply side and inverters on the load side; similarly, when any inverter on the load side fails, it will not affect the power supply to the load, and the reliability of the system is greatly improved. Based on this automatic control method, a highly reliable AC / DC integrated distribution network system can be realized.

[0026] When AC load 1 fails or is disconnected, there is no need to immediately change the transmission power of transformer 1 and DC power supply 1. The system can distribute the energy of transformer 1 and DC power supply 1 to other load sides, thereby improving the fault tolerance rate of the system's power transmission.

[0027] The implementation of this invention has the following beneficial effects: The AC / DC integrated distribution network system proposed in the embodiments of the invention has the characteristics of fast control speed and high long-distance transmission efficiency. It does not require the transformation and capacity expansion of the original AC line distribution network, makes full use of the transmission capacity of the existing equipment, responds quickly in the event of a fault, and effectively combines the main distribution equipment. Under the premise that the relay protection device is activated, it does not affect the normal power supply of the load, which can effectively improve the reliability of power supply. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the topology of an AC / DC integrated distribution network system according to an embodiment of the present invention.

[0030] Figure 2 This is a flowchart illustrating an intelligent operation and maintenance method for an AC / DC integrated distribution network system according to Embodiment 2 of the present invention. Detailed Implementation

[0031] The following description of the embodiments is taken with reference to the accompanying drawings, which illustrate specific embodiments in which the invention can be implemented.

[0032] Please refer to Figure 1 As shown, Embodiment 1 of the present invention provides an AC / DC integrated distribution network system, including: an AC distribution network with a radial topology and a DC distribution network with a grid topology. The AC distribution network and the DC distribution network exchange energy through inverters on the power supply side and the load side, respectively. The AC and DC distribution lines are isolated from the power supply and the load through circuit breakers. Under fault conditions, the AC distribution network operates in a closed loop through the DC distribution network to provide uninterrupted power supply.

[0033] In this embodiment, the AC distribution network has a radial topology, while the DC distribution network has a mesh topology. This facilitates the transformation of a radial distribution network powered by a single AC power source into one powered by multiple power sources, allowing the DC power source to serve as a backup power source for critical loads. Furthermore, it enables AC and DC power sources to act as backup power sources for each other, improving power supply reliability. Simultaneously, it can be integrated with rapid fault location, fault isolation control, and protection technologies for the power grid, enabling users to perform uninterrupted maintenance and troubleshooting even after individual AC or DC line faults.

[0034] Specifically, each transformer substation consists of an AC distribution line and a corresponding DC distribution line. AC distribution line 1 and AC distribution line n have the same voltage level, as do DC distribution line 1 and DC distribution line n. The AC distribution lines between different substations are not connected, but the DC distribution lines are directly interconnected via circuit breakers. Under fault conditions, the AC distribution network can operate in a closed loop through the DC distribution network, ensuring uninterrupted power supply. Here, n is a natural number greater than 1.

[0035] Compared to AC power sources, distributed DC power sources have smaller capacities. Therefore, a DC power grid is set up for interconnection, with AC and DC power sources serving as backups for each other. By transforming the traditional single-source power distribution network into a multi-source power distribution network, energy can be transferred through the DC distribution network in the event of a line fault, improving power supply reliability. Since the transmission capacity of DC lines at the same voltage level is much larger than that of AC lines, and the power loss is small when DC lines are interconnected over long distances, power flow transfer can be achieved under the condition of multiple AC line faults.

[0036] (1) Power supply side

[0037] Transformers (AC power sources) are not only connected to the AC distribution network, and DC power sources are not only connected to the DC distribution network; they are electrically connected through power electronic inverters. When transformer 1 fails, it is disconnected by the circuit breaker, and the system can supply power to the load through DC power source 1, DC power source n, and transformer n; similarly, when DC power source 1 fails, power can be supplied to the load through DC power source n, transformer 1, and transformer n. The DC power sources and transformers work together to transmit and distribute electrical energy.

[0038] (2) Circuit breaker

[0039] In this topology, the circuit breaker, in conjunction with the relay protection system, can automatically, quickly, and selectively disconnect faulty equipment from the power system, preventing further damage to the faulty equipment and ensuring that other fault-free parts quickly resume normal operation. On the other hand, it acts as a switch connecting the AC and DC distribution networks, changing the connection and disconnection of lines by opening and closing them, thereby altering the topology of the AC and DC distribution networks and playing an important role in the distribution and transmission of electrical energy.

[0040] The AC / DC integrated power distribution network system proposed in this invention has the characteristics of fast control speed and high long-distance transmission efficiency. It does not require the modification and capacity expansion of the original AC line power distribution network, makes full use of the transmission capacity of existing equipment, responds quickly in the event of a fault, and effectively combines the main power distribution equipment (circuit breakers, transformers, etc.). Under the premise that the relay protection device is activated, it does not affect the normal power supply to the load, and can effectively improve the reliability of power supply.

[0041] Traditional power distribution systems rely on overall management systems such as Supervisory Control and Data Acquisition (SCADA) and Energy Management Systems (EMS). This management depends on manual input by enterprise grid workers and manual correction by distribution network maintenance and inspection personnel. It also relies on remote terminals such as Distribution Terminal Units (DTUs), Feeder Terminal Units (FTUs), and Transformer Terminal Units (TTUs) to acquire electrical data for system status monitoring and stable operation. The application of digital technologies can not only improve the management level of power distribution equipment and the efficiency of energy utilization, but also realize the digital, miniaturized, and chip-integrated transformation of power distribution equipment, reducing the footprint and losses of traditional equipment and further supporting carbon emission reduction. Information and communication technologies and various intelligent terminals and power-specific chips will be widely used in new business models such as virtual power plants and source-grid-load interaction. The integration of primary and secondary equipment and edge computing-based intelligent terminal equipment will change the form and function of traditional remote terminals such as DTU, FTU, and TTU in power distribution networks.

[0042] Therefore, please refer to Figure 2 As shown, Embodiment 2 of the present invention provides an intelligent operation and maintenance method for the AC / DC integrated distribution network system described in Embodiment 1 of the present invention, comprising:

[0043] Step S1: Perform a status evaluation on the main power distribution equipment based on edge computing to determine the status evaluation level of the main power distribution equipment;

[0044] Step S2: Assess the likelihood and severity of the consequences of a failure in the main power distribution equipment, calculate the risk value of the main power distribution equipment, conduct a failure risk assessment based on the risk value, and determine the risk level.

[0045] Step S3: Based on the determined risk level, classify the power distribution equipment into corresponding categories and construct the AC / DC integrated power grid operation and maintenance strategy for each category;

[0046] Step S4: Based on the status evaluation level of the main power distribution equipment, obtain the fault type and fault location of the main power distribution equipment, and establish a corresponding AC / DC integrated power grid fault operation and maintenance strategy.

[0047] Step S5: Based on the AC / DC integrated power grid planned operation and maintenance strategy and the DC integrated power grid fault operation and maintenance strategy, obtain the intelligent operation and maintenance strategy of the AC / DC integrated distribution network system.

[0048] Specifically, the main contents of step S1, the status evaluation of power distribution main equipment based on edge computing, include: digitizing the status information of power distribution main equipment, establishing the relationship between fault types and status quantities, and determining the weights of status quantities.

[0049] First, the status information of the main power distribution equipment is digitized. Intelligent power equipment that achieves lightweight algorithms and is applied to edge computing possesses powerful computing capabilities, primarily manifested in fault prediction, diagnosis, and status assessment based on sensor data. Based on actual operating conditions, this invention uses the fault tree method to revise the defect standard library, ensuring a one-to-one correspondence between the defect standard library and evaluation items. Then, the deductions and weights of state variables are determined, establishing a standard status evaluation model for the main power distribution equipment.

[0050] A fault tree is a logical relationship diagram that describes the causal relationships of faults in a diagnostic object. It graphically describes the logical relationships between various faults in a system, demonstrating the logical reasoning process and propagation paths between each fault, and intuitively illustrating the causes and modes of system faults. Analyzing the relationship and probability of state variable faults and equipment faults leads to a diagnosis of the fault location, thereby identifying state variables closely related to equipment faults and completing the compilation of a defect standard library.

[0051] Secondly, the relationship between fault type and state variables is obtained by deriving fault probabilities. This invention uses the fault-Bayesian network method, which first forms a tree diagram of bottom-level events, intermediate events, and top-level events, and then uses conditional probabilities to represent the impact of bottom events on the system or device. Conversely, given that a fault has already occurred in the system, the conditional probability of component failure can be derived to obtain the probabilistic importance of bottom events to top events, exposing the weaknesses of the system or device. Therefore, each state variable can be assigned a corresponding basic deduction value based on the magnitude of its conditional probability.

[0052] This embodiment combines the advantages of both fault tree and Bayesian network models: it has low requirements for existing information and can perform reasoning under conditions of incomplete or uncertain information; Bayesian networks can fully utilize and express given statistical data. As defined, a Bayesian network can not only represent the dependencies between variables but also the strength of those dependencies, using prior knowledge to perform corresponding probability deductions. This process is essentially the extraction and expression of patterns or information contained in the provided statistical data; Bayesian networks have the characteristic of bidirectional reasoning. This makes the resulting model and future probability calculations more consistent with reality. It avoids the uncertainty and arbitrariness of directly constructing Bayesian networks through manual methods or data analysis, improving the objectivity of state evaluation.

[0053] Next, the weights of the state variables are determined. Since each conditional attribute (i.e., each state variable) exhibits different importance in the system, the importance of each state variable must be determined. This invention uses rough set theory to calculate the weights of the state variables. Rough set theory determines the weights of state variables through attribute importance. When determining attribute importance, rough set theory mainly considers the impact on system classification when the attribute is present and when it is absent. If removing the attribute significantly changes the attribute classification, then the attribute importance is relatively high.

[0054] Rough set theory can handle incomplete data and data with many variables and objective functions. This is a significant advantage that many other methods lack. It also excels at handling data with unclear boundary conditions—that is, imprecise or ambiguous data. It can find the minimum representation of knowledge, i.e., knowledge reduction, thus simplifying the expression of knowledge as much as possible without altering the overall nature of the data. Rough set theory has a sound theoretical foundation and only requires objective statistical data, without needing any other artificial prior knowledge.

[0055] Step S2 involves conducting a fault risk assessment. The risk of main power distribution equipment refers to the magnitude of potential losses to the equipment assets. Equipment risk assessment, based on equipment condition evaluation, assesses the likelihood and severity of equipment failures, determining the risks the equipment faces and may face. This invention employs a quantitative risk method to assess the risk level of the equipment.

[0056] After determining the risk level of the equipment in step S2, step S3 categorizes the equipment into four classes based on risk: Class I, Class II, Class III, and Class IV. The main aspects of operation and maintenance include four categories: inspection, maintenance, testing, and repair. Emphasis should be placed on strengthening the operation and maintenance of Class I and Class II equipment, shortening their maintenance cycles. For Class III and Class IV equipment, their maintenance cycles can be appropriately extended, but the longest cycle must not exceed the minimum standard.

[0057] In step S4, the AC / DC integrated power grid planned fault operation and maintenance strategy is an emergency power transfer strategy formulated for equipment that has already failed, which mainly includes the following aspects:

[0058] (1) When AC line 1 fails, the line is disconnected by the circuit breaker, and the system can supply power to the load through DC distribution line 1, DC distribution line n and AC distribution line n; similarly, when any one DC distribution line fails, the other three lines can provide reliable power.

[0059] (2) When transformer 1 fails, the transformer is disconnected by the circuit breaker, and the system can supply power to the load through DC power supply 1, DC power supply n and transformer n; similarly, when DC power supply 1 fails, the load can be supplied by DC power supply n, transformer 1 and transformer n.

[0060] (3) When the inverter on the transformer 1 and DC power supply 1 side fails, the inverter is disconnected by the circuit breaker, and the system can supply power to AC load 1 through other inverters on the power supply side and inverters on the load side; similarly, when any inverter on the load side fails, it will not affect the power supply to the load, and the reliability of the system is greatly improved. Based on this automatic control method, a highly reliable AC / DC integrated distribution network system can be realized.

[0061] (4) When AC load 1 fails or is disconnected, there is no need to immediately change the transmission power of transformer 1 and DC power supply 1. The system can distribute the energy of transformer 1 and DC power supply 1 to other load sides, thereby improving the fault tolerance rate of system power transmission.

[0062] Finally, step S5 combines the AC / DC integrated power grid planned operation and maintenance strategy and the AC / DC integrated power grid planned fault operation and maintenance strategy to establish a complete intelligent operation and maintenance strategy for the AC / DC integrated distribution network system.

[0063] It should be noted that in the AC / DC integrated distribution network topology proposed in Embodiment 1 of this invention, suitable relay protection devices and other main distribution network equipment can be added to replicate the above topology. Alternatively, optimized control methods for power flow and power quality, as well as system startup methods under fault conditions, can be added to optimize the performance of the topology and further improve the power supply reliability of the distribution network system. In the AC / DC integrated power grid planned operation and maintenance and fault operation and maintenance strategies proposed in Embodiment 2 of this invention, other intelligent algorithms and mathematical methods can be used for equipment status evaluation. The fault-Bayesian network method can be modified to determine the intrinsic relationship between fault types and state variables. Other methods can be used to replace rough set theory to determine state variable indices, further optimizing the intelligent operation and maintenance strategy.

[0064] As can be seen from the above description, the beneficial effects of the present invention are as follows: The AC / DC integrated distribution network system proposed in the embodiments of the present invention has the characteristics of fast control speed and high long-distance transmission efficiency. It does not require the transformation and capacity expansion of the original AC line distribution network, makes full use of the transmission capacity of the existing equipment, responds quickly in the event of a fault, and effectively combines with the main distribution equipment. Under the premise that the relay protection device is activated, it does not affect the normal power supply of the load, and can effectively improve the reliability of power supply.

[0065] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A smart operation and maintenance method for an AC / DC integrated distribution network system, characterized in that, include: Step S1: Perform a status evaluation on the main power distribution equipment based on edge computing to determine the status evaluation level of the main power distribution equipment; Step S2: Assess the likelihood and severity of the consequences of a failure in the main power distribution equipment, calculate the risk value of the main power distribution equipment, conduct a failure risk assessment based on the risk value, and determine the risk level. Step S3: Based on the determined risk level, classify the main power distribution equipment into corresponding categories and construct the AC / DC integrated power grid operation and maintenance strategy for each category; Step S4: Based on the status evaluation level of the main power distribution equipment, obtain the fault type and fault location of the main power distribution equipment, and establish a corresponding AC / DC integrated power grid fault operation and maintenance strategy. Step S5: Based on the AC / DC integrated power grid planned operation and maintenance strategy and the DC integrated power grid fault operation and maintenance strategy, obtain the intelligent operation and maintenance strategy of the AC / DC integrated distribution network system; The digitization of the status information of the main power distribution equipment specifically involves: using the fault tree method to revise the defect standard library so that the defect standard library corresponds one-to-one with the evaluation items, then determining the deduction and weight of the status quantities, and establishing a standard status evaluation model for the main power distribution equipment. The specific method for establishing the relationship between fault type and state variable is as follows: using the fault-Bayesian network method, the relationship between fault type and state variable is obtained by deriving the fault probability. Specifically, determining the weights of the state variables involves using rough set theory to calculate the weights of the state variables. In step S4, the AC / DC integrated power grid planned fault operation and maintenance strategy is an emergency power transfer strategy formulated for equipment that has already failed. The emergency power transfer strategy Including the following aspects: When AC line 1 fails, the line is disconnected by the circuit breaker, and the system can supply power to the load through DC distribution line 1, DC distribution line n and AC distribution line n; similarly, when any one DC distribution line fails, the other three lines can provide reliable power. When transformer 1 fails, it is disconnected by the circuit breaker, and the system can supply power to the load through DC power supply 1, DC power supply n and transformer n; similarly, when DC power supply 1 fails, the load can be supplied by DC power supply n, transformer 1 and transformer n. When the inverter on the transformer 1 and DC power supply 1 side fails, the inverter is disconnected by the circuit breaker, and the system can supply power to AC load 1 through other inverters on the power supply side and inverters on the load side; similarly, when any inverter on the load side fails, it will not affect the power supply to the load, and the reliability of the system is greatly improved. Based on this automatic control method, a highly reliable AC / DC integrated distribution network system can be realized. When AC load 1 fails or is disconnected, there is no need to immediately change the transmission power of transformer 1 and DC power supply 1. The system can distribute the energy of transformer 1 and DC power supply 1 to other load sides, thereby improving the fault tolerance rate of the system's power transmission.

2. The intelligent operation and maintenance method according to claim 1, characterized in that, Step S1 specifically includes: digitizing the status information of the main power distribution equipment, establishing the relationship between fault types and status quantities, and determining the weights of the status quantities.

3. The intelligent operation and maintenance method according to claim 1, characterized in that, Step S3 classifies the main power distribution equipment into four categories based on equipment risk: Category I, Category II, Category III, and Category IV; the operation and maintenance content includes four major categories: inspection, maintenance, testing, and overhaul.

4. The intelligent operation and maintenance method according to claim 3, characterized in that, The specific operation and maintenance strategies for constructing each type of AC / DC integrated power grid plan include: focusing on strengthening the operation and maintenance of Class I and Class II equipment and shortening their operation and maintenance cycles; for Class III and Class IV equipment, appropriately extending their operation and maintenance cycles, but the longest cycle shall not exceed the minimum standard.

Images