Intelligent hybrid contactor system and corresponding control method thereof

Abstract

The application relates to the field of rail transit electrical control technology, in particular to an intelligent hybrid contactor system and a corresponding control method, the system is provided with at least two sets of independent contactor channels, each channel comprises a hybrid contactor unit formed by series connection of a mechanical contactor and a solid-state contactor, an intelligent driving control module, a state monitoring module and a health evaluation module, the state monitoring module collects loop current, mechanical and solid-state contactor monitoring data to form a health data set, the health evaluation module calculates a health degree according to the health data set, dynamically generates a derating and hierarchical early warning strategy, cooperates with the intelligent driving control module to realize accurate control of the device, and meanwhile, the channels are interconnected through a redundancy management module, the redundancy architecture of multi-channel cross-voting and fault takeover improves the safety of the system. The application can realize contactor full life cycle state monitoring and predictive maintenance, and effectively improves the operation reliability of the rail transit electrical system.

Description

Technical Field

[0001] This application relates to the field of rail transit electrical control technology, and in particular to an intelligent hybrid contactor system and its corresponding control method. Background Technology

[0002] In the electrical control system of rail transit vehicles, contactors are the core actuators, undertaking the critical functions of circuit switching, load switching, and electrical protection. Their performance, reliability, and service life directly determine the operational stability and driving safety of the rail transit vehicle's electrical system. Currently, the mainstream contactors used in the rail transit field are mainly of two types: traditional mechanical contactors and pure solid-state contactors. However, these are difficult to adapt to the stringent application scenarios of rail transit, which require high reliability, long life, and high safety. Among them, traditional mechanical contactors rely on mechanical contacts to achieve circuit switching. They have a mature structure and low conduction loss, but under frequent disconnection and high current switching conditions, they are prone to generating strong electric arcs. The electric arcs continuously burn the contacts, causing problems such as contact wear, oxidation, and deformation. This leads to a short overall service life and low operational reliability of the contactor, and it lacks intelligent monitoring and control capabilities, making it unable to meet the development needs of modern intelligent operation and maintenance in rail transit. Pure solid-state contactors rely on power electronic devices to achieve arc-free switching, completely solving the problem of arc erosion. However, they have drawbacks such as large conduction voltage drop and severe heat generation during operation. Long-term operation results in high energy consumption and heat dissipation pressure. In addition, the device manufacturing cost is high, which greatly increases the equipment operation, maintenance and replacement costs, limiting large-scale application.

[0003] To combine the advantages of low loss and low cost of mechanical contactors with the arc-free switching of solid-state contactors, existing technologies have proposed hybrid contactor solutions. These solutions effectively achieve arc-free circuit switching by combining mechanical contacts with power electronic switches in series and parallel, avoiding some inherent defects of traditional single contactors. However, these traditional hybrid contactor solutions generally lack online sensing capabilities for the entire lifecycle health status of the contactor. They cannot monitor various degradation processes such as mechanical contact wear, surface oxidation, actuation time drift, and solid-state device performance degradation in real time, nor can they accurately assess the health status of the devices based on operational data. Currently, the operation and maintenance of rail transit contactors relies entirely on manual periodic inspections and reactive repairs after failures. This not only results in low maintenance efficiency and high labor costs but also fails to predict the risk of device aging and performance failure in advance, making predictive maintenance difficult. Furthermore, manual inspection suffers from detection lag and insufficient accuracy, failing to promptly detect hidden degradation faults in contactors, easily leaving hidden electrical system safety hazards and failing to meet the core requirements of high reliability and intelligent operation and maintenance for modern rail transit electrical systems. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides an intelligent hybrid contactor system and its corresponding control method, which can realize full life cycle status monitoring and predictive maintenance of contactors, effectively improving the operational reliability of rail transit electrical systems.

[0005] The first aspect of this application provides an intelligent hybrid contactor system, the system comprising at least two independent contactor channels, each contactor channel comprising: At least one hybrid contactor unit, each hybrid contactor unit including a mechanical contactor and a solid contactor, and a main current path formed by the mechanical contactor and the solid contactor connected in series; The intelligent drive control module is electrically connected to the mechanical contactor coil and the solid-state contactor control terminal respectively, and is used to output timing control signals to control the hybrid contactor unit to achieve zero-voltage connection and zero-current disconnection actions according to the timing control signals. The status monitoring module is used to acquire the main circuit current of the main current path, the first monitoring data of the mechanical contactor, and the second monitoring data of the solid contactor to obtain a health monitoring dataset. The health assessment module calculates a health score based on the health monitoring dataset, dynamically generates a deduction strategy and a graded early warning strategy based on the health score, and outputs the deduction strategy and the graded early warning strategy to the intelligent drive control module. The at least two independent contactor channels are connected through a redundancy management module. The redundancy management module adopts a safe redundancy architecture. Different channels perform independent calculations and cross-compare decision results. When the decisions are consistent, the vote passes and the output is allowed. When a single channel fails, the other channel takes over. When the decisions of any two channels are inconsistent, the system enters a safe state.

[0006] In one optional implementation, the intelligent drive control module includes a dynamic derating module and a graded load shearing module; The dynamic derating module is used to calculate a derating coefficient based on the health score according to the joint accelerated life model, and the derating coefficient is configured in association with the health score; and to dynamically adjust the carrying current of the hybrid contactor unit according to the derating coefficient. The graded load cut-off module is used to receive the graded early warning strategy and divide the protection mechanism into multiple levels based on the health score and the main circuit arc fault detection result. Different protection mechanisms correspond to different graded early warning strategies. When the health score is in the first preset score range, the graded early warning strategy is determined to be a level one early warning strategy. When the health score is in the second preset score range, the graded early warning strategy is determined to be a level two early warning and soft cut-off protection strategy. When the health score is in the third preset score range, or when the main circuit arc fault detection result indicates that an arcing fault has been detected in the main circuit, the graded early warning strategy is determined to be a level three alarm and emergency cut-off protection strategy.

[0007] In one optional implementation, the soft-cut protection strategy includes controlling the solid-state contactor to gradually reduce the current in a ramp manner, and disconnecting the mechanical contactor after the main circuit current drops to a preset current threshold.

[0008] In one alternative implementation, the emergency disconnection protection strategy includes controlling the solid-state contactor to shut down in microseconds and rapidly disconnect the mechanical contactor.

[0009] In an optional implementation, the expression for the joint accelerated lifetime model is: ; Where L is the contactor lifespan, C is a proportionality constant related to the contactor material and structure, I is the carrying current, and n is the current stress exponent. The activation energy is given by ΔT, where ΔT is the temperature change amplitude caused by switching on and off, m is the temperature cycling index, and k is the derating factor. The lifetime extension factor corresponding to the derating factor is... .

[0010] In one optional implementation, the determination of the derating factor must simultaneously satisfy both safety constraints and availability constraints; the derating factor is based on the Pareto optimality principle, and the optimal derating factor is selected within the range of derating factors that simultaneously satisfy the safety constraints and the availability constraints; the safety constraint is that the contactor's lifespan is safely operated until the preset maintenance cycle after derating, and the lifespan extension factor is not less than a set threshold; the availability constraint is that the actual carrying current of the contactor after derating is not less than the minimum operating current, and the corresponding derating factor is not less than a set lower limit value.

[0011] In one optional implementation, when the hybrid contactor unit is controlled by the timing control signal to perform a zero-voltage closing action, the solid-state contactor is turned on, the mechanical contactor is closed when the voltage across the mechanical contactor drops to within a preset voltage threshold, and then the solid-state contactor is turned off; when the hybrid contactor unit is controlled by the timing control signal to perform a zero-current disconnecting action, the solid-state contactor is turned on, the mechanical contactor is disconnected when the current flowing through the mechanical contactor drops to within a preset current threshold, and then the solid-state contactor is turned off.

[0012] In an optional implementation, the system further includes a communication module that uses an MVB, CAN, or Ethernet communication interface to upload the health score, the deduction strategy, and the graded early warning strategy to an external system.

[0013] A second aspect of this application provides a control method for an intelligent hybrid contactor system, applied to the intelligent hybrid contactor system, the method comprising: The condition monitoring module collects the main circuit current and the operating parameters of mechanical and solid contactors in real time, generates a health monitoring dataset, and sends it to the health assessment module. The health assessment module calculates a comprehensive health score based on the health monitoring dataset and matches the corresponding depreciation coefficient with the joint accelerated life model; it generates a graded early warning strategy based on the health score and the arc detection results, and sends the depreciation coefficient and the graded early warning strategy to the intelligent drive control module. The dynamic derating module dynamically adjusts the carrying current of the hybrid contactor unit according to the derating coefficient. The graded load resection module executes the corresponding graded early warning strategy, and performs early warning reporting, soft resection or emergency resection operations according to different protection levels. The redundancy management module cross-compares and votes on the decision results of multiple channels; when the decision results are consistent, the corresponding on / off action is executed; when a single channel fails, the normal channel takes over the load; when the channel decisions are inconsistent or all channels fail, the system enters a safe state. The intelligent drive control module outputs timing control signals to control the hybrid contactor unit to complete zero-voltage connection and zero-current disconnection actions.

[0014] In summary, the intelligent hybrid contactor system and its corresponding control method provided in this application, through... The modular collaborative design, specifically by configuring a condition monitoring module and a health assessment module in each independent contactor channel, constructs a comprehensive, real-time health monitoring and assessment system for contactors. The condition monitoring module can collect real-time data on the main circuit current of the main current path, the first monitoring data of mechanical contactors, and the second monitoring data of solid-state contactors. This comprehensively covers key parameters of device degradation, such as mechanical contact wear, surface oxidation, operating time drift, and performance degradation of solid-state components, forming a complete health monitoring dataset. This enables uninterrupted online monitoring of the entire lifecycle degradation process of hybrid contactor units, solving the problems of inaccurate detection of latent device degradation faults and monitoring lag. Based on this, the health assessment module performs data analysis and calculation using the real-time collected health monitoring dataset, accurately outputting a contactor health score, quantifying the device's health status, and dynamically matching corresponding derating strategies and graded early warning strategies based on the score results. Simultaneously, the control strategies are transmitted to the intelligent drive control module, achieving intelligent management based on the actual health status of the equipment. This architecture abandons the outdated operation and maintenance model of traditional manual periodic inspections and reactive fault repair. It can predict the aging, performance degradation, and failure risks of components in real time, and carry out preventive operation and maintenance interventions in advance, effectively realizing predictive maintenance of contactor equipment. At the same time, with the safety redundancy architecture of multiple independent contactor channels and redundant management modules, it ensures the operational stability of the equipment during health monitoring, condition assessment, and intelligent control, avoiding the control failure problem caused by single-channel monitoring and calculation failures. It significantly improves the operational reliability and safety of the rail transit electrical control system, and fully adapts to the core development needs of intelligent and highly reliable operation and maintenance in modern rail transit. Attached Figure Description

[0015] Figure 1 This is a system architecture diagram of an intelligent hybrid contactor system shown in an embodiment of this application; Figure 2 This is another system architecture diagram of an intelligent hybrid contactor system shown in an embodiment of this application; Figure 3 This is a schematic diagram illustrating a health assessment and dynamic dehydration process according to an embodiment of this application; Figure 4 This is a schematic diagram illustrating a graded loading resection process according to an embodiment of this application; Figure 5 This is a logical schematic diagram illustrating a dual-channel redundancy switching embodiment of this application; Figure 6 This is a flowchart illustrating a control method for an intelligent hybrid contactor system according to an embodiment of this application. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] The following will clearly and completely describe the concept, specific structure, and technical effects of the present invention in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention. Furthermore, all connections / linkages involved in the patent do not simply refer to direct contact between components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The various technical features in this invention can be combined interactively without contradicting each other.

[0018] Reference Figure 1 The diagram shown is a system architecture diagram of an intelligent hybrid contactor system according to an embodiment of this application. The system includes at least two independent contactor channels. Each contactor channel includes at least one hybrid contactor unit, an intelligent drive control module, a status monitoring module, a health assessment module, and a redundancy management module.

[0019] To facilitate understanding of the inventive concept of this application, the following embodiments take the braking control circuit of a rail transit train as the application scenario, with two independent contactor channels (channel A and channel B respectively) as an example. That is, the system adopts two contactor channels to form a two-out-of-two redundant architecture, and the rated operating current is set to 100A for illustration.

[0020] At least one hybrid contactor unit, each hybrid contactor unit including a mechanical contactor and a solid contactor, and a main current path formed by the mechanical contactor and the solid contactor connected in series.

[0021] When the system is configured with two independent contactor channels, each channel contains a set of hybrid contactor units. These units serve as the system's main power actuators, undertaking the core function of switching the main circuit's power supply on and off. (See also...) Figure 2In this embodiment, the hybrid contactor unit in channel A consists of a solid-state contactor A (IGBT / MOSFET) and a mechanical contactor A (contact) connected in series to form a complete main current path. Similarly, the unit in channel B consists of a solid-state contactor B and a mechanical contactor B connected in series. There are no parallel branches between the two. The power circuit wiring uses vehicle-grade flame-retardant cables, and the terminals employ an anti-loosening crimping structure, adapting to the vibration and alternating high and low temperature operating environment of rail transit vehicles. The mechanical contactor is a general-purpose AC mechanical contactor for rail transit, characterized by vibration resistance, shock resistance, and high insulation levels. The contact material is silver-based oxide, suitable for long-term high-current switching conditions. The solid-state contactor uses IGBT power devices as the core switching element, integrating a freewheeling diode and a simple temperature sampling pin, achieving a response speed in the microsecond range, and can precisely cooperate with the mechanical contactor to complete sequential switching actions.

[0022] The main contacts of the mechanical contactor and the power pole of the solid-state contactor are connected in series in the forward direction. Current flows from the circuit input terminal through the solid-state contactor and then the mechanical contactor before being output to the downstream load, forming a single main current path. This series structure is the physical basis for achieving zero-voltage connection and zero-current disconnection. The hybrid contactor units of the two contactor channels are completely independent in hardware. The power circuits, mechanical structures, and installation positions are isolated from each other, and there is no electrical coupling, thus avoiding the problem of single-point fault propagation at the hardware level. In actual assembly, the two sets of hybrid contactor units are arranged in separate sections in the equipment cabinet, with the spacing meeting the electrical safety insulation distance requirements of the vehicle. They are also equipped with independent heat dissipation ducts. The mechanical contactor focuses on structural dust protection, while the solid-state contactor is equipped with an aluminum heat sink to enhance heat dissipation.

[0023] During full-condition operation, the hybrid contactor unit does not perform switching actions independently, but rather receives timing commands from the intelligent drive control module and works in coordination. Under normal current-carrying conditions, the current is mainly carried by the mechanical contactor with lower conduction losses, while the solid-state contactor only operates briefly during connection and disconnection, significantly reducing the long-term heat generation problem of solid-state devices. For operating conditions involving frequent vehicle starts and stops and repeated circuit switching, the series architecture, combined with timing control, can completely eliminate mechanical contact arcing, effectively slowing down contact wear and oxidation, and extending the overall service life. The hardware parameters and specifications of the two sets of units are completely identical, ensuring consistent dual-channel operating characteristics and providing a hardware foundation for subsequent redundant voting and cross-comparison, fully adapting to the usage requirements of key electrical circuits such as main circuits and auxiliary circuits of rail transit vehicles. This module has a simple hardware structure and high reliability, while combining the dual advantages of low conduction losses of traditional mechanical contactors and arc-free operation of solid-state contactors.

[0024] The intelligent drive control module is electrically connected to the mechanical contactor coil and the solid-state contactor control terminal, respectively, and is used to output timing control signals. According to the timing control signals, the hybrid contactor unit is controlled to achieve zero-voltage connection and zero-current disconnection.

[0025] Refer to together Figure 2 Each contactor channel is independently configured with an intelligent drive control module, with channel A equipped with intelligent drive control module A and channel B equipped with intelligent drive control module B. The intelligent drive control module provides timing control signals for the hybrid contactor unit and is the core control unit for achieving zero-voltage connection and zero-current disconnection. The module uses an industrial-grade microcontroller as the main control chip, with an operating temperature range of -40℃ to +85℃, fully adaptable to the harsh environment of rail transit vehicles. The module circuitry is surge-proofed and electromagnetic interference-resistant, meeting on-board EMC electromagnetic compatibility standards. The intelligent drive control module connects to the mechanical contactor coil and the solid-state contactor control terminal through independent drive circuits. The two drive circuits are isolated from each other to avoid signal crosstalk. A drive fault self-checking circuit is also included to identify abnormal states such as coil disconnection and open circuit at the control terminal in real time, perfectly matching the architecture shown in the attached diagram where the module drives two types of contactors respectively.

[0026] In one optional implementation, when the hybrid contactor unit is controlled by the timing control signal to perform a zero-voltage closing action, the solid-state contactor is turned on, the mechanical contactor is closed when the voltage across the mechanical contactor drops to within a preset voltage threshold, and then the solid-state contactor is turned off; when the hybrid contactor unit is controlled by the timing control signal to perform a zero-current disconnecting action, the solid-state contactor is turned on, the mechanical contactor is disconnected when the current flowing through the mechanical contactor drops to within a preset current threshold, and then the solid-state contactor is turned off.

[0027] In some embodiments, considering the main current path structure of the mechanical contactor and solid-state contactor connected in series in this system and the high-frequency switching operation of rail transit, the intelligent drive control module outputs high-precision timing control signals and drives the hybrid contactor unit to complete two types of standard actions based on preset logic. When performing a zero-voltage switching action, the intelligent drive control module first outputs a high-level conduction signal to the solid-state contactor, enabling the solid-state contactor to connect to the main current path first. After the status monitoring module reports that the voltage across the mechanical contactor has stabilized and dropped to near 0 (i.e., below the preset voltage threshold of 5V), the module then outputs a pull-in signal to the mechanical contactor coil, driving the mechanical contacts to close. After the mechanical contactor completes the closing action, the module cancels the conduction signal of the solid-state contactor, turning off the solid-state device. The timing deviation of the entire switching process is controlled at the microsecond level, ensuring that the voltage across the mechanical contacts is approximately zero at the moment of closing, thus avoiding the generation of a switching arc. During zero-current disconnection, the intelligent drive control module first turns on the solid-state contactor, allowing the solid-state device to shunt the main circuit current. Once the status monitoring module detects that the current flowing through the mechanical contactor has dropped to near zero (i.e., below the preset current of 0.5A), the module outputs a disconnection signal to disconnect the mechanical contactor. After the mechanical contacts are completely disconnected, the solid-state contactor is then turned off, achieving zero-current disconnection and eliminating the disconnection arc.

[0028] Through the above optional implementation methods, arc-free switching can be achieved under all operating conditions, significantly reducing mechanical contact losses, adapting to the working characteristics of frequent start-stop and repeated switching of rail transit vehicles, and achieving long-term stable operation of the system.

[0029] In some embodiments, the intelligent drive control module simultaneously receives derating strategies from the same channel health assessment module and adjusts the drive logic based on derating parameters: when derating is required, the module controls the solid-state contactor to operate in chopper current-limiting mode, achieving precise current limiting of the circuit through high-frequency switching; it can also transmit derating signals to the host computer according to instructions to cooperate with the load side to complete power regulation. The two sets of intelligent drive control modules operate independently, each generating its own channel drive instructions without interfering with each other. The module has signal latching and instruction synchronization functions, and can cooperate with the hardware voter to complete decision signal output and interlocking. When the redundant architecture determines that the channel is faulty or the decision is inconsistent, the drive module can quickly interlock the output and forcibly cut off the power circuit. In addition, the module collects and uploads its own drive status in real time, and cooperates with the whole machine fault diagnosis to ensure accurate timing and reliable execution of switching actions, providing stable control support for arc-free operation and derating operation of the hybrid contactor unit.

[0030] The status monitoring module is used to acquire the main circuit current of the main current path, the first monitoring data of the mechanical contactor, and the second monitoring data of the solid contactor to obtain a health monitoring dataset.

[0031] Refer to together Figure 2Each contactor channel is independently configured with a status monitoring module, with channel A configured with status monitoring module A and channel B configured with status monitoring module B. These modules are responsible for collecting operating parameters of the main circuit and devices from all dimensions, integrating them to form a standardized health monitoring dataset. This dataset provides raw data support for backend health assessment and fault diagnosis. In this embodiment, the status monitoring module integrates current sampling units, voltage sampling units, temperature sampling units, action timing sampling units, and environmental parameter sampling units. All sampling devices are automotive-grade components, with a sampling frequency set to 1kHz. This allows for real-time capture of transient changes in the circuit, and the sampling accuracy meets the testing requirements for rail transit electrical equipment. Data transmission uses an internal differential bus, providing strong anti-interference capabilities, consistent with the dual-channel independent acquisition and non-data-sharing architecture shown in the attached diagram. Specifically, the status monitoring module first collects the main current path parameters. A high-precision Hall current sensor is connected in series to the main circuit to collect the instantaneous value, effective value, and current fluctuation of the main circuit current in real time. The sampled data is synchronously recorded as a current change curve to determine the load condition and device current-carrying state. Secondly, the module collects the first monitoring data corresponding to the mechanical contactor, specifically including parameters such as the dynamic voltage at both ends of the mechanical contactor, contact resistance, engagement time, release time, cumulative number of on / off actions, and coil operating voltage. The contact resistance uses a four-wire sampling method to eliminate detection errors caused by lead resistance and accurately capture resistance increases caused by contact oxidation and wear. The action time is obtained by comparing the timing of the coil energization signal and the contact status feedback signal to calculate the action time drift. The cumulative number of actions has a power-off storage function, ensuring data is not lost after power failure and continuously recording the fatigue mileage of mechanical components. Simultaneously, the module collects the second monitoring data corresponding to the solid-state contactor, mainly including parameters such as solid-state device chip temperature, drive terminal voltage, drain current, and device operating temperature rise rate. Temperature is measured in real-time using a surface-mount thermistor attached to the IGBT chip surface to monitor the heating status of the solid-state device and prevent overheating damage. In addition, the module also simultaneously collects external environmental parameters such as the internal ambient temperature of the channel and the vibration amplitude of the vehicle body as a basis for device aging correction. All collected main circuit current, mechanical contactor monitoring data, solid-state contactor monitoring data, and environmental parameters are packaged in a pre-defined data format to form a complete health monitoring dataset, which is then transmitted in real-time point-to-point to the health assessment module within the same channel.

[0032] The two sets of status monitoring modules independently collect and output data, ensuring that the data sources for both channels are authentic and independent. The modules feature anomaly data marking functionality; when sampled values ​​exceed normal thresholds, abnormal data is automatically marked and prioritized for uploading, allowing for early prediction of device failure trends. The entire sampling logic covers electrical, mechanical, thermal, and environmental parameters, providing comprehensive data dimensions and fully characterizing the entire lifecycle operating status of the hybrid contactor unit, thus providing a reliable data foundation for health assessment and strategy generation.

[0033] The health assessment module calculates a health score based on the health monitoring dataset, dynamically generates a deduction strategy and a graded early warning strategy based on the health score, and outputs the deduction strategy and the graded early warning strategy to the intelligent drive control module.

[0034] Refer to together Figure 2 Each contactor channel is equipped with an integrated health assessment and decision-making module. Channel A has module A, and channel B has module B. The modules integrate health assessment functions and tiered load shedding control logic, working in tandem. The health assessment section is responsible for data analysis, health level calculation, and strategy generation. The tiered shedding section receives protection strategies and executes corresponding protection actions. The modules are integrated on the control circuit board, with inter-board signal transmission delay of less than 1ms, meeting the response speed requirements for vehicle-mounted equipment fault handling. The health assessment section uses an embedded microprocessor as its core, with built-in fixed scoring algorithms, weighting rules, and threshold logic. It can autonomously complete calculations without external programming, and also reserves parameter interfaces to support fine-tuning of weights and scoring standards on-site according to different contactor models. The calculation results form a "decision result" output to the hardware voting unit.

[0035] In an optional implementation, calculating the health score based on the health monitoring dataset includes: The contact resistance increment, action time drift, cumulative number of actions, and ambient temperature / vibration parameters in the health monitoring dataset are extracted as evaluation indicators. Each evaluation indicator is scored separately according to the preset weights. The scores of each indicator are combined with their corresponding weights to obtain a comprehensive health score ranging from 0 to 100.

[0036] The health assessment section continuously receives health monitoring datasets from the status monitoring module of this channel. In this embodiment, four independent and complementary key features that best characterize the remaining lifespan and health status of the contactor are selected to perform a baseline weighted score on the system: contact resistance increment ΔR, actuation time drift, cumulative actuation count, and ambient temperature / vibration. Then, contact resistance increment, actuation time drift, cumulative actuation count, and ambient temperature / vibration are used as evaluation indicators, and sub-item scoring and weighted calculations are performed according to preset weights. Among these, the main contacts of the mechanical contactor experience irreversible increases in contact resistance due to arc erosion, surface oxidation, and mechanical wear, making it the most direct and sensitive indicator reflecting the contact's electrical life. The increase in contact resistance mainly stems from mechanical wear and material aging, thus it is assigned the highest weight, with a contact resistance increment weight of 40%. The engagement and release times gradually lengthen or shorten (jitter) due to spring fatigue, mechanism jamming, and changes in electromagnet residual magnetism, reflecting the real-time health status, and are assigned the second highest weight, with an actuation time drift weight of 30%. The cumulative number of actions directly corresponds to the design ratings of mechanical and electrical life. Although this embodiment achieves arc-free switching, the fatigue of mechanical components (springs, shafts, housings) still follows the "stress-strength" model. The cumulative number of actions is the basic mileage indicator of fatigue life, and the weight of the cumulative number of actions is set to 20%. Temperature accelerates chemical reactions (oxidation, insulation aging) and the degradation of semiconductor devices (IGBT / MOSFET), and vibration exacerbates the wear and malfunction risk of mechanical contactors. These are external stress factors, not characteristics of equipment degradation itself. They mainly correct the boundary conditions of the health score of the first three parameters (for example, in a high-temperature environment, the same increase in contact resistance corresponds to a lower remaining life). Therefore, they are given a lower base weight, and the environmental temperature / vibration weight is set to 10%.

[0037] Furthermore, the system performs weighted summation based on preset scoring rules to calculate a comprehensive health score ranging from 0 to 100. The health assessment module has a complete set of preset scoring rules that can automatically determine the score for each indicator. For example, it can automatically score based on factors such as the multiple of contact resistance relative to the initial value, the percentage of action time drift, the proportion of action frequency to the rated lifespan, and the severity of the environment, all without the need for manual intervention. Specifically, the scoring rules for each indicator are as follows: 100 points for contact resistance increment ΔR less than 1.2 times the initial value, 70 points for 1.2 to 2 times the initial value, and 30 points for greater than or equal to 2 times the initial value; 100 points for action time drift less than 5% of the standard action time, 60 points for 5% to 15%, and 20 points for greater than 15%; 100 points for cumulative action count less than 80% of the rated mechanical life, 50 points for 80% to 95% of the rated life, and 10 points for greater than or equal to 95% of the rated life; 100 points for ambient temperature and vibration parameters under normal conditions, 60 points for severe conditions, and 20 points for extreme conditions. The health assessment module calculates the scores for each indicator according to the above scoring rules, and then performs a weighted sum based on the weights of each indicator to obtain a comprehensive health score ranging from 0 to 100.

[0038] To facilitate understanding of the inventive concept of this application, an example of a preset weight and preset scoring rule is provided below, as shown in Table 1.

[0039] Table 1:

[0040] It should be noted that the weights are not static and can be optimized based on different product models and application scenarios.

[0041] The intelligent drive control module may include a dynamic derating module and a tiered load shedding module. After calculating the comprehensive health score, the dynamic derating module can dynamically generate derating strategies and tiered early warning strategies based on the score range. When formulating the dynamic derating strategy, a derating coefficient is calculated based on the health score using a joint accelerated life model (Arrhenius-Coffin-Manson joint model), and the derating coefficient is configured in association with the health score; the carrying current of the hybrid contactor unit is dynamically adjusted according to the derating coefficient. The expression for the Arrhenius-Coffin-Manson joint model is: ; Where L is the contactor life, C is a proportionality constant related to the contactor material and structure, I is the carrying current (the derating factor directly affects this variable), and n is the current stress index (3.5~5.5, depending on the contact material). The activation energy is 0.6~1.5 eV, ΔT is the temperature change amplitude caused by switching on and off, m is the temperature cycling index (2.0~4.0), and k is the derating factor. The lifetime extension factor corresponding to the derating factor k is quantified and calculated as follows: .

[0042] To facilitate understanding of the inventive concept of this application, the following provides an example of the relationship between the derating factor and the lifetime extension factor for a typical silver-based oxide contact material (n=4.2), as shown in Table 2.

[0043] Table 2:

[0044] It should be noted that the determination of the derating factor must simultaneously satisfy two engineering constraints: a safety constraint and an availability constraint. The derating factor is based on the Pareto optimality principle, and the optimal derating factor is selected within the range of derating factors that simultaneously satisfy the safety constraint and the availability constraint. The safety constraint is that the contactor's lifespan after derating is to operate safely until the preset maintenance cycle, and the lifespan extension factor is not less than a set threshold. The availability constraint is that the actual carrying current of the contactor after derating is not less than the minimum operating current, and the corresponding derating factor is not less than a set lower limit value.

[0045] Constraint 1 (Security Constraint): Extending the lifespan after derating must ensure that the equipment can operate safely until the next maintenance cycle: L×Life extension factor ≥T For example, the overhaul cycle of rail transit vehicles is T = 5 to 8 years, and after taking a safety margin, the lifespan extension multiple is required to be ≥ 3.

[0046] Constraint 2 (Availability Constraint): The derating load capacity must meet the system's minimum operating requirements: I derated ≥I min ; According to the traction system design specifications, the minimum available current should not be less than 65% of the rated value (corresponding to k≥0.65). Therefore, the effective range of the derating factor that simultaneously satisfies both constraints is 0.65~0.78.

[0047] Within this interval, trade-offs are made based on the Pareto optimality principle: k=0.8 (20% derating): The lifespan extension factor is 2.6, which is lower than the safety threshold of 3 times and does not meet the safety constraints; k=0.7 (30% derating): The lifespan extension factor is 4.5, which meets the safety requirement of ≥3 times; at the same time, the derating factor is 0.7, which corresponds to 70% of the rated current, which is higher than the availability lower limit of 65%. This maximizes the lifespan extension effect and load capacity, and is the Pareto optimal solution. k=0.65 (35% derating): The lifespan extension is approximately 7 times, which meets the safety constraints, but the derating factor is at the availability boundary, and the load capacity is only 65% ​​of the rated value. There is no redundancy space, which is not conducive to coping with load fluctuations.

[0048] Therefore, in this embodiment, for mildly degraded contactors with a health score in the range of 60≤H<80, a derating factor k=0.7 is selected as the optimal value, achieving the best balance between extended lifespan and system availability.

[0049] Based on engineering constraints and Pareto optimization results, the deduction coefficient is linked to the comprehensive health score range to form a tiered deduction strategy. (See also...) Figure 3 and Figure 4 When the health score is higher than or equal to the first preset threshold (e.g., the first preset threshold is set to 80 points), that is, when the comprehensive health score H≥80, the contactor is determined to be in a healthy state with no obvious degradation. The derating factor is set to 1.0, and the corresponding derating strategy is determined to be the full-load operation strategy, where the contactor operates at full load with rated current. When the health score is within the range of the first and second preset thresholds (e.g., the second preset threshold is set to 60 points, 60~80 points), that is, when 60≤H<80, the contactor is determined to be slightly degraded. The optimal derating factor is selected as 0.7, and the corresponding derating strategy is determined to be current limiting of 70%. The contactor operates at 70% of rated current, and the synchronous output graded early warning strategy is the first-level early warning protection strategy. When the health level falls within the range of the second and third preset thresholds (e.g., the third preset threshold is set to 40 points, 40~60 points), i.e., when 40≤H<60, the contactor is determined to have entered an accelerated degradation period, exceeding the range that can be safely supported by conventional derating. To avoid sudden failure, the derating factor is further set to 0.5, and the corresponding derating strategy is determined to be current limiting of 50%. The contactor operates at 50% of its rated current, significantly reducing current stress, delaying contact deterioration, and simultaneously outputting a secondary warning and soft-cut protection strategy. When the health level falls below the third preset threshold, i.e., when H<40, the contactor has entered a severely degraded state, or when an arc is detected in the circuit, a tertiary alarm and emergency cut-off protection strategy is directly output, directly triggering load cut-off, prohibiting the channel from carrying load current, and switching to redundant channel operation. The first preset threshold is greater than the second preset threshold, and the second preset threshold is greater than the third preset threshold.

[0050] When implementing the derating strategy, the dynamic derating module achieves derating control in two ways: local chopper current limiting and load-coordinated derating. Local chopper current limiting involves the intelligent drive control module controlling the solid-state contactor to operate in high-frequency chopper mode, limiting the circuit current by adjusting the duty cycle to directly achieve the current upper limit corresponding to the derating factor. Load-coordinated derating involves the system sending a derating command to the vehicle's host computer, with the back-end load side cooperating to reduce power demand, matching the contactor's current-carrying capacity after derating, and ensuring coordinated overall system operation. The intelligent drive control module adjusts the circuit current limiting threshold by a coefficient to achieve dynamic load management, and simultaneously packages the protection strategy and "decision results" and sends them to the hardware voting unit, where the graded load cut-off control logic distinguishes the protection level and executes actions.

[0051] In an optional implementation, the graded load cut-off module is used to receive the graded early warning strategy and classify multiple protection mechanisms according to the health score and the main circuit arc fault detection result, with different protection mechanisms corresponding to different graded early warning strategies. When the health score is in a first preset score range, the graded early warning strategy is determined to be a level one early warning strategy; when the health score is in a second preset score range, the graded early warning strategy is determined to be a level two early warning and soft cut-off protection strategy; when the health score is in a third preset score range, or when the main circuit arc fault detection result indicates that an arcing fault has been detected in the main circuit, the graded early warning strategy is determined to be a level three alarm and emergency cut-off protection strategy.

[0052] In some embodiments, the graded load cut-off module has a built-in three-level protection mechanism, which uses a comprehensive health score as the core judgment criterion, and combines the main circuit arc fault detection results for supplementary triggering. The specific triggering conditions and corresponding strategies are as follows: First preset score range (Level 1 warning): When the health score is between 60 and 80 (60≤H<80), the contactor enters a state of mild degradation. Its performance has decreased but it still has basic current carrying capacity. Derating operation is performed and a warning report is issued. The second preset score range (level 2 warning and soft cut-off): when the health score is between 40 and 60 (40≤H<60), the contactor enters an accelerated degradation state, and the contact wear and action time drift are close to the safety boundary. It needs to be taken out of operation under controllable conditions. The third preset score range (level 3 alarm and emergency cut-off): if the health score is below 40 points (H < 40), or if the status monitoring module detects an arcing fault in the main circuit, the contactor is in a severely degraded or faulty state, and the faulty circuit must be isolated immediately.

[0053] Refer to together Figure 3 and Figure 4When the graded load shedding module determines that the contactor's health score has entered the first preset score range (H < 60), it determines the graded early warning strategy as a level one early warning strategy. The module immediately sends a level one early warning signal to the vehicle central control unit (TCMS) and the ground maintenance system, including the contactor channel number, current health score, derating factor, and degradation trend data. Simultaneously, it issues a corresponding derating instruction to the dynamic derating module. If 60 ≤ H < 80, a derating factor of 0.7 is executed, and the circuit current is limited to 70A; if 40 ≤ H < 60, a derating factor of 0.5 is executed, and the circuit current is limited to 50A. The contactor maintains its derating operation state and does not perform a shedding action. The redundant channel synchronously bears part of the load, and the overall system operation is uninterrupted. At the same time, it prompts maintenance personnel to perform maintenance during the next train return to the depot for inspection. When the graded load shedding module determines that the contactor's health score has entered the second preset score range (H < 50), it determines the graded early warning strategy as a level two early warning and soft shedding protection strategy, and executes arc-free controllable shedding. The module sends a "request shutdown" signal to the vehicle's TCMS, requesting power disconnection upon completion of the current task, thus reserving an operation window for soft disconnection. The intelligent drive control module controls the solid-state contactor to gradually reduce the circuit current at a rate of 10% reduction in rated current every 10ms, bringing the current smoothly close to zero. When the circuit current drops below a preset threshold (0.5A), the module controls the mechanical contactor to disconnect, achieving arc-free soft disconnection. After disconnection, the module sends a fault channel isolation command to the redundancy management module, allowing another healthy channel to independently take over all loads, ensuring uninterrupted operation of critical train systems. Simultaneously, the module records the current and voltage waveform data and health status change curves of this soft disconnection, uploading them to the maintenance system for fault backtracking. When the graded load disconnection module determines that the contactor health score enters the third preset score range (H < 40), or the status monitoring module detects an arcing fault in the main circuit, the graded early warning strategy is immediately determined to be a level three alarm and emergency disconnection protection strategy, executing instantaneous fault isolation. The module triggers a three-level alarm signal, which is simultaneously sent to the TCMS, the vehicle-mounted safety monitoring unit, and the ground operation and maintenance platform, indicating a serious contactor failure. The intelligent drive control module controls the solid-state contactor to shut down in microseconds, while simultaneously disconnecting the mechanical contactor, completing the isolation of the fault circuit within 1ms to avoid secondary faults caused by arc propagation and contact welding. The redundancy management module immediately switches the load to the healthy channel, with the redundant contactor independently bearing the entire load current. The module collects and stores current, voltage, temperature, and health data before and after the fault, generating a fault waveform report to provide complete data support for subsequent fault analysis.

[0054] To facilitate understanding of the inventive concept of this application, an example of a graded early warning strategy is provided below, as shown in Table 4.

[0055] Table 4:

[0056] Among them, the graded load shedding module and the redundancy management module work together in real time to ensure smooth load switching under different protection levels: During a Level 1 warning, redundant channels and faulty channels operate in tandem with reduced capacity, without affecting the overall availability of the system; During the secondary soft cut-off, the redundant channel enters standby mode in advance and seamlessly takes over the load after the faulty channel is cut off, avoiding power outages to critical train equipment. During a Level 3 emergency disconnection, the redundant channel immediately switches to operation, while simultaneously triggering the hardware interlock of the faulty channel to prevent the faulty circuit from reconnecting to the system.

[0057] This multi-level protection mechanism enables full lifecycle management of the contactor from early warning to fault isolation, avoiding unnecessary downtime and achieving rapid isolation in the event of a serious fault, thus balancing system availability and operational safety.

[0058] The health assessment and decision-making modules of the two channels operate independently, generating strategies independently, and the results are uploaded to the hardware voting unit. The modules have data storage capabilities, capable of recording historical health status, derating records, and fault action records long-term. This data can be uploaded to the vehicle's TCMS and ground maintenance system via a secure communication bus, supporting predictive maintenance. The coordinated operation of these two modules enables self-sensing of device health status, load adaptation, and hierarchical protection, addressing the shortcomings of traditional contactors in predicting degradation and offering only one protection method from a control perspective.

[0059] The at least two independent contactor channels are connected through a redundancy management module. The redundancy management module adopts a safe redundancy architecture. Different channels perform independent calculations and cross-compare decision results. When the decisions are consistent, the vote passes and the output is allowed. When a single channel fails, the other channel takes over. When the decisions of any two channels are inconsistent, the system enters a safe state.

[0060] The redundancy management module (also known as the hardware voter) is the central management unit of the entire system. It connects two independent contactor channels and employs a two-out-of-two safety redundancy architecture to achieve dual-channel collaboration, voting, fault switching, and safety protection. The module is equipped with dedicated hardware voting circuitry and a secure communication bus. It is a core component ensuring high system availability and avoiding single points of failure. The hardware circuitry features a redundant design, resulting in an extremely low probability of failure, fully meeting the high safety requirements of rail transit operation. The hardware voter communicates bidirectionally with the health assessment and decision-making modules within the two contactor channels, collecting the "decision results" of each channel in real time to complete the overall channel status summary and logical judgment.

[0061] Refer to together Figure 5After the system is powered on, it first executes a dual-channel initialization and self-test process. First, hardware initialization is performed, with the status monitoring module, health assessment module, and intelligent drive control module of both contactor channels completing parameter configuration, register initialization, and sensor self-tests respectively. Next, a two-to-two cross-verification is performed. The redundancy management module sends test commands to channels A and B via the safety communication bus to verify the communication link, data acquisition, and control output functions of the two channels. Each channel generates its own self-test results and cross-compares them. After confirming that the hardware and software are fault-free, it enters normal operation. If any channel fails its self-test, the system directly enters a safety disconnect state, and the hardware voter forcibly cuts off all outputs to prevent the fault from spreading.

[0062] Under normal operating conditions, the two contactor channels operate completely independently. The redundancy management module performs cross-comparison and voting output at fixed intervals. The status monitoring modules of channel A and channel B respectively collect the main circuit current and the operating parameters of the mechanical and solid-state contactors to form a health monitoring dataset. The health assessment module independently calculates the comprehensive health scores HA and HB based on their respective datasets and generates on / off decision commands CA and CB (0 or 1, representing off / on). The redundancy management module triggers a cross-comparison every 0ms to collect the health scores and decision commands of the two channels. If and only if CA == CB (the decision commands are consistent) and HA and HB are both ≥ the threshold (the health status of both channels is normal), the hardware voter outputs an allow signal, executes the on / off command, and the contactor unit operates normally. If any condition is not met, the voter refuses to output the command and enters the fault handling process.

[0063] When cross-comparison detects an abnormal health status in a single channel, the system switches from dual-channel operation to single-channel degraded operation mode. Specifically, if HA ≥ 60 and HB < 60, channel B is determined to be faulty, and channel A independently takes over the entire load. Channel A executes the corresponding derating strategy based on its own health score, and the system reports a "single-channel fault, degraded operation alarm" to prompt maintenance personnel to inspect channel B when the train returns to the depot. If HA < 60 and HB ≥ 60, channel A is determined to be faulty, and channel B independently takes over the load. During degraded operation, the system maintains periodic self-checks and mutual checks. If the faulty channel recovers, it can automatically switch back to dual-channel redundancy mode; if the fault persists, it maintains single-channel operation until the next maintenance.

[0064] When cross-comparison detects abnormal status or inconsistent decisions between the two channels, the system immediately enters safety protection logic. If |HA - HB| > 20 (excessive difference in health scores between the two channels) or CA ≠ CB (inconsistent on / off decision commands), the redundancy management module determines that the system has a logical fault or communication anomaly. The hardware voter immediately cuts off all output commands, the solid-state contactors of both contactor channels turn off within microseconds, and the mechanical contactors quickly disconnect, isolating the faulty circuit. The system synchronously records the health data, decision commands, and fault waveforms of both channels and uploads them to the vehicle central control unit and the ground maintenance platform for fault retrospective analysis.

[0065] When cross-comparison detects that both channels are in a severely degraded state, the system performs graded load shedding. Specifically, if HA < 40 and HB < 40, it is determined that both contactor channels have entered a severe fault state. The redundancy management module triggers a level three alarm and executes an emergency shedding action. The solid-state contactor shuts off in microseconds, the mechanical contactor quickly disconnects, and simultaneously the system sends a stop request to the vehicle's TCMS to coordinate with the train to achieve a safe stop and prevent load runaway due to contactor failure.

[0066] To detect latent faults early, the system continuously performs periodic self-tests and mutual tests during operation. The two channels periodically interact via heartbeat signals and test pulses to verify the integrity of the communication link. The redundancy management module periodically sends test commands to channels A and B to verify the normal functioning of the control outputs. If any channel fails its self-test or communication is interrupted, the system immediately triggers a safety cutoff state, forcibly cutting off all outputs to ensure train operation safety.

[0067] This safety redundancy architecture completely solves the single-point failure risk of traditional single contactor systems through dual-channel independent operation, cross-voting, fault takeover and safety isolation throughout the entire process. It not only ensures the continuity of train operation, but also achieves fast and reliable safety isolation in the event of a fault, fully meeting the high availability requirements of the rail transit field.

[0068] In an optional implementation, the system further includes a communication module that uses an MVB, CAN, or Ethernet communication interface to upload the health score, the deduction strategy, and the graded early warning strategy to an external system.

[0069] In some embodiments, the intelligent hybrid contactor system is equipped with an independent communication module that supports MVB, CAN, or Ethernet communication interfaces to establish data links with the vehicle central control unit (TCMS) and the ground maintenance system. During system operation, the communication module periodically uploads the comprehensive health score of each channel, the currently effective derating coefficient and derating operation status, graded early warning / alarm information, fault clearing events, and waveform data to the external system, enabling remote monitoring of health status, fault tracing, and predictive maintenance data interaction. The communication module also receives configuration commands from the host computer, supporting remote adjustment of parameters such as health assessment weights, scoring rules, and derating coefficients, as well as firmware upgrades.

[0070] Reference Figure 6 The diagram shown is a flowchart illustrating a control method for an intelligent hybrid contactor system according to an embodiment of this application. The control method for the intelligent hybrid contactor system includes the following steps.

[0071] S61, Status Data Acquisition.

[0072] After the system is powered on, the status monitoring module continuously collects the main circuit current, contact resistance increment ΔR, action time drift, cumulative action count, and ambient temperature / vibration, forming a health monitoring dataset and sending it to the health assessment module.

[0073] S62, Health Calculation and Strategy Generation.

[0074] The health assessment module calculates a comprehensive health score based on a health monitoring dataset, according to preset weights and scoring rules; it calculates a depreciation coefficient by combining the joint accelerated life model; and it generates a graded early warning strategy based on the health score and arc fault detection results, and sends the depreciation coefficient and graded early warning strategy to the intelligent drive control module.

[0075] S63, dynamic derating control and tiered load shedding execution.

[0076] The dynamic derating module adjusts the carrying current of the hybrid contactor unit according to the derating factor by either chopping and limiting the current with a solid-state contactor or sending a derating command to the load side, thereby achieving adaptive current limiting operation that matches the health status.

[0077] The graded load shedding module executes corresponding actions based on the graded early warning strategy: Level 1 Warning: Maintain reduced spending and report warning signals; Level 2 warning: Perform soft cut-off, disconnect the mechanical contactor after ramp flow reduction; Level 3 alarm: Execute emergency disconnection, shut down the solid-state contactor and disconnect the mechanical contactor in microseconds, synchronously isolate the fault circuit and record the waveform.

[0078] S64, Redundant Voting and Channel Management.

[0079] The redundancy management module cross-compares and votes on the decision results of the two channels: if the decisions are consistent and the channel is healthy, the on / off command is allowed to be executed; if a single channel fails, the normal channel takes over the load independently; if the decisions are inconsistent or both channels fail, the system enters a safe state and forcibly cuts off the output.

[0080] S65, zero-voltage connection and zero-current disconnection.

[0081] The intelligent drive control module outputs timing control signals.

[0082] Zero-voltage turn-on: First turn on the solid-state contactor, and then close the mechanical contactor after the voltage across the mechanical contactor drops below the threshold. Then turn off the solid-state contactor. Zero-current disconnection: First turn on the solid-state contactor, and then disconnect the mechanical contactor when the current flowing through it drops below the threshold. Finally, turn off the solid-state contactor.

[0083] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0084] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0085] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. An intelligent hybrid contactor system, characterized in that, The system includes at least two independent contactor channels, each contactor channel comprising: At least one hybrid contactor unit, each hybrid contactor unit including a mechanical contactor and a solid contactor, and a main current path formed by the mechanical contactor and the solid contactor connected in series; The intelligent drive control module is electrically connected to the mechanical contactor coil and the solid-state contactor control terminal respectively, and is used to output timing control signals to control the hybrid contactor unit to achieve zero-voltage connection and zero-current disconnection actions according to the timing control signals. The status monitoring module is used to acquire the main circuit current of the main current path, the first monitoring data of the mechanical contactor, and the second monitoring data of the solid contactor to obtain a health monitoring dataset. The health assessment module calculates a health score based on the health monitoring dataset, dynamically generates a deduction strategy and a graded early warning strategy based on the health score, and outputs the deduction strategy and the graded early warning strategy to the intelligent drive control module. The at least two independent contactor channels are connected through a redundancy management module. The redundancy management module adopts a safe redundancy architecture. Different channels perform independent calculations and cross-compare decision results. When the decisions are consistent, the vote passes and the output is allowed. When a single channel fails, the other channel takes over. When the decisions of any two channels are inconsistent, the system enters a safe state.

2. The intelligent hybrid contactor system according to claim 1, characterized in that, The intelligent drive control module includes a dynamic de-rating module and a graded load-bearing resection module; The dynamic derating module is used to calculate a derating coefficient based on the health score according to the joint accelerated life model, and the derating coefficient is configured in association with the health score; and to dynamically adjust the carrying current of the hybrid contactor unit according to the derating coefficient. The graded load cut-off module is used to receive the graded early warning strategy and divide the protection mechanism into multiple levels according to the health score and the main circuit arc fault detection result. Different protection mechanisms correspond to different graded early warning strategies. When the health score is within the first preset score range, the graded early warning strategy is determined to be a level one early warning strategy; when the health score is within the second preset score range, the graded early warning strategy is determined to be a level two early warning and soft cut-off protection strategy; when the health score is within the third preset score range, or when the main circuit arc fault detection result indicates that an arc fault has been detected in the main circuit, the graded early warning strategy is determined to be a level three alarm and emergency cut-off protection strategy.

3. The intelligent hybrid contactor system according to claim 2, characterized in that, The soft cut-off protection strategy includes controlling the solid-state contactor to gradually reduce the current in a ramp manner, and disconnecting the mechanical contactor after the main circuit current drops to a preset current threshold.

4. The intelligent hybrid contactor system according to claim 2, characterized in that, The emergency disconnection protection strategy includes controlling the solid-state contactor to shut down in microseconds and quickly disconnecting the mechanical contactor.

5. The intelligent hybrid contactor system according to claim 2, characterized in that, The expression for the joint accelerated lifetime model is: ； Where L is the contactor lifespan, C is a proportionality constant related to the contactor material and structure, I is the carrying current, and n is the current stress exponent. The activation energy is given by ΔT, where ΔT is the temperature change amplitude caused by switching on and off, m is the temperature cycling index, and k is the derating factor. The lifetime extension factor corresponding to the derating factor is... .

6. The intelligent hybrid contactor system according to claim 2, characterized in that, The determination of the derating factor must simultaneously satisfy both safety constraints and availability constraints; the derating factor is based on the Pareto optimality principle, and the optimal derating factor is selected within the range of derating factors that simultaneously satisfy the safety constraints and availability constraints; the safety constraint is that after derating, the contactor's lifespan can be safely operated until the preset maintenance cycle, and the lifespan extension multiple is not less than a set threshold. The availability constraint is that the actual carrying current of the contactor after derating is not lower than the minimum operating current, and the corresponding derating factor is not less than the set lower limit value.

7. The intelligent hybrid contactor system according to claim 1, characterized in that, When the hybrid contactor unit is controlled to perform a zero-voltage switching action according to the timing control signal, the solid-state contactor is turned on, the mechanical contactor is closed when the voltage across the mechanical contactor drops to within a preset voltage threshold, and then the solid-state contactor is turned off. When the hybrid contactor unit is controlled to perform a zero-current disconnection operation according to the timing control signal, the solid-state contactor is turned on, the mechanical contactor is disconnected when the current flowing through the mechanical contactor drops to within a preset current threshold, and then the solid-state contactor is turned off.

8. The intelligent hybrid contactor system according to claim 1, characterized in that, The system also includes a communication module, which uses an MVB, CAN or Ethernet communication interface to upload the health score, the deduction strategy and the graded early warning strategy to an external system.

9. A control method for an intelligent hybrid contactor system, characterized in that, The method, applied to the intelligent hybrid contactor system according to any one of claims 1 to 8, comprises: The condition monitoring module collects the main circuit current and the operating parameters of mechanical and solid contactors in real time, generates a health monitoring dataset, and sends it to the health assessment module. The health assessment module calculates a comprehensive health score based on the health monitoring dataset and matches the corresponding depreciation coefficient with the joint accelerated life model; it generates a graded early warning strategy based on the health score and the arc detection results, and sends the depreciation coefficient and the graded early warning strategy to the intelligent drive control module. The dynamic derating module dynamically adjusts the carrying current of the hybrid contactor unit according to the derating coefficient. The graded load resection module executes the corresponding graded early warning strategy, and performs early warning reporting, soft resection or emergency resection operations according to different protection levels. The redundancy management module cross-compares and votes on the decision results of multiple channels; when the decision results are consistent, the corresponding on / off action is executed; when a single channel fails, the normal channel takes over the load; when the channel decisions are inconsistent or all channels fail, the system enters a safe state. The intelligent drive control module outputs timing control signals to control the hybrid contactor unit to complete zero-voltage connection and zero-current disconnection actions.

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