A method and device for automatically switching on a diesel generator and a terminal device

Abstract

The application is suitable for the field of automatic control technology of power system, and provides a kind of diesel generator's spare power automatic switching control method, device and terminal equipment, the method comprises: first, obtain multidimensional monitoring data, multidimensional monitoring data includes city power grid side city power electrical parameter, line fault signal, and the real-time load working condition parameter of power consumption side.Then, based on city power electrical parameter and line fault signal, determine the fault working condition type of city power grid side.Finally, according to the fault working condition type of city power grid side and the real-time load working condition parameter of power consumption side, the spare power automatic switching control strategy of diesel generator is determined, wherein, spare power automatic switching control strategy is used to determine whether to start diesel generator as standby power supply.The method realizes the fine classification of power grid fault by obtaining the electrical analog quantity and line fault signal of city power grid side, and overcomes the misoperation and misstart problem caused by single monitoring signal.

Description

Technical Field

[0001] This application belongs to the field of power system automatic control technology, and in particular relates to a method, device and terminal equipment for automatic switching control of diesel generators. Background Technology

[0002] Currently, diesel generators serve as the core emergency backup power source for critical power distribution systems, and their backup control logic is crucial for ensuring uninterrupted power supply to loads after a power outage.

[0003] However, existing diesel generator automatic transfer control technology generally adopts control logic with a fixed threshold and fixed delay for a single electrical parameter. It determines whether there is a fault on the mains power grid side by only the mains voltage and frequency, and completes the diesel generator start-up, switch switching and load connection actions according to a fixed sequence. Its technical architecture is fixed and the judgment mechanism is simple, which leads to low fault judgment accuracy and frequent problems of backup transfer malfunction and failure to operate. Summary of the Invention

[0004] This application provides a method, device, and terminal equipment for automatic backup switching control of diesel generators. It can solve the problem that existing automatic backup switching control methods for diesel generators generally use a single electrical parameter with a fixed threshold and a fixed delay control logic to complete the diesel generator start-up and load connection actions according to a fixed sequence, resulting in low fault identification accuracy and frequent problems of backup switching malfunctions and failures to start.

[0005] In a first aspect, embodiments of this application provide a method for automatic switching control of a diesel generator, including: Acquire multi-dimensional monitoring data, including mains electrical parameters and line fault signals on the mains power grid side, and real-time load condition parameters on the power consumption side; Based on the mains electrical parameters and the line fault signal, determine the fault condition type on the mains power grid side; Based on the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, a backup automatic transfer control strategy for the diesel generator is determined accordingly. The backup automatic transfer control strategy is used to determine whether to start the diesel generator as a backup power source.

[0006] In one possible implementation of the first aspect, the mains electrical parameters on the mains grid side include mains voltage fluctuation value, mains frequency fluctuation value, mains voltage value, and mains frequency value; The process of determining the fault condition type on the mains power grid side based on the mains electrical parameters and the line fault signal includes: If the mains voltage fluctuation value and the mains frequency fluctuation value meet the first-level disturbance threshold condition, the first duration is less than the first preset duration, and there is no line fault signal, the fault condition type on the mains grid side is determined to be an instantaneous disturbance fault; wherein, the first duration is used to characterize the duration for which the mains voltage fluctuation value and the mains frequency fluctuation value meet the first-level disturbance threshold condition; When the mains voltage value is in the secondary voltage drop range, the mains frequency value is in the preset frequency range, the second duration is between the first preset duration and the second preset duration, and there is no line fault signal, the fault condition type on the mains grid side is determined to be a short-time voltage drop fault; wherein, the second duration is used to characterize the duration for which the mains voltage value is in the secondary voltage drop range and the mains frequency value is in the preset frequency range; If the mains voltage value is less than the secondary voltage drop range, the mains frequency value exceeds the preset frequency range, and the third duration is greater than the second preset duration, or if any one of the line fault signal, bus fault signal, or upstream switch trip signal exists, the fault condition type on the mains grid side is determined to be a permanent power outage fault; wherein, the third duration is used to characterize the duration for which the mains voltage value is less than the secondary voltage drop range and the mains frequency value exceeds the preset frequency range.

[0007] In one possible implementation of the first aspect, determining the automatic transfer switch control strategy for the diesel generator based on the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side includes: When the fault condition type on the mains power grid side is the instantaneous disturbance fault, the automatic transfer switch control strategy is determined to not start the diesel generator, and the mains power grid side maintains its original operating state. When the fault condition type on the mains power grid side is the short-time voltage drop fault, the switching delay time is determined according to the real-time load condition parameters on the power consumption side. After waiting for the switching delay time, if the mains power grid side does not return to normal, the automatic transfer switch control strategy is determined to start the diesel generator as a backup power source. When the fault condition type on the mains power grid side is the permanent power outage fault, the automatic transfer switch control strategy is determined to start the diesel generator as a backup power source.

[0008] In one possible implementation of the first aspect, after determining that the automatic transfer switch strategy is to start the diesel generator as a backup power source, the method includes: The start-up readiness status and circuit breaker mechanism status of the diesel generator are verified; wherein, the start-up readiness status of the diesel generator includes the diesel generator preheating status, battery voltage status, and diesel generator set fault status. If the start-up readiness status of the diesel generator and the status of the circuit breaker mechanism are both normal, then the diesel generator is started. After the diesel generator has started and the voltage and frequency values ​​output by the diesel generator meet the preset grid connection conditions, the corresponding switching control action is executed according to the real-time load condition parameters of the power consumption side. If the start-up readiness status of the diesel generator and / or the status of the circuit breaker mechanism are found to be abnormal, a fault-tolerant self-test is performed.

[0009] In one possible implementation of the first aspect, when the diesel generator has started and the voltage and frequency values ​​output by the diesel generator meet preset grid connection conditions, a corresponding switching control action is executed based on the real-time load condition parameters of the power consumption side, including: When the load rate is in the first preset range in the real-time load condition parameters on the power consumption side, a direct switching control action is triggered to control the switch to close and connect to the backup power supply. When the load rate is in the second preset range in the real-time load condition parameters on the power consumption side, a graded and step-by-step switching control action is triggered to gradually switch on the loads supplied by the backup power supply according to the preset timing and load priority.

[0010] In one possible implementation of the first aspect, after the diesel generator has started and the voltage and frequency values ​​output by the diesel generator meet preset grid connection conditions, the method includes: Real-time monitoring of the restored voltage and frequency values ​​on the mains power grid side; If the recovery voltage value is within the rated voltage allowable range, the recovery frequency value is within the rated frequency allowable range, and the fourth duration of the recovery voltage value and the recovery frequency value is greater than the preset recovery duration, then the mains power grid side is determined to be truly restored.

[0011] In one possible implementation of the first aspect, the step of performing a fault-tolerant self-test if the start-ready state of the diesel generator and / or the state of the circuit breaker mechanism is abnormal includes: If the diesel generator’s start-ready status is abnormal, a second start command will be issued after a first preset delay. If the diesel generator is in a normal start-up ready state, but the circuit breaker mechanism is in an abnormal state, then the circuit breaker mechanism is isolated and the standby circuit breaker mechanism is called to complete the load power supply. If the diesel generator's start-up ready state and the circuit breaker mechanism's state are both abnormal and all conventional backup power supply procedures fail, then the simplest emergency switching procedure will be executed to force the backup power supply to be put into operation.

[0012] In one possible implementation of the first aspect, the method further includes: After the fault-tolerant self-check process is completed, fault data is generated, which includes the fault location and fault type.

[0013] Secondly, embodiments of this application provide a standby automatic start-up control device for a diesel generator, comprising: The acquisition module is used to acquire multi-dimensional monitoring data, which includes mains electrical parameters and line fault signals on the mains power grid side, as well as real-time load condition parameters on the power consumption side. The identification module is used to determine the fault condition type on the mains power grid side based on the mains electrical parameters and the line fault signal; The determination module is used to determine the backup automatic transfer control strategy of the diesel generator according to the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, wherein the backup automatic transfer control strategy is used to determine whether to start the diesel generator as a backup power source.

[0014] Thirdly, embodiments of this application provide a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the automatic backup control method for the diesel generator described in any of the above claims.

[0015] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the automatic backup control method for a diesel generator as described in any of the preceding claims.

[0016] Fifthly, embodiments of this application provide a computer program product that, when run on a terminal device, causes the terminal device to execute the automatic backup control method for a diesel generator as described in any of the first aspects.

[0017] The beneficial effects of the embodiments in this application compared with the prior art are: This application provides a method for automatic transfer switching control of a diesel generator, comprising: first, acquiring multi-dimensional monitoring data, including mains electrical parameters and line fault signals on the mains power grid side, and real-time load condition parameters on the power consumption side. Then, based on the mains electrical parameters and line fault signals, determining the fault condition type on the mains power grid side. Finally, according to the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, determining a corresponding automatic transfer switching control strategy for the diesel generator, wherein the automatic transfer switching control strategy is used to determine whether to start the diesel generator as a backup power source. This method, by acquiring electrical analog quantities and line fault signals on the mains power grid side, achieves refined classification of power grid faults, overcoming the problems of malfunction and false start caused by a single monitoring signal. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, 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 this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic flowchart of a backup automatic switching control method for a diesel generator provided in one embodiment of this application; Figure 2 This is a flowchart illustrating a backup automatic switching control method for a diesel generator according to another embodiment of this application; Figure 3 This is a schematic diagram of the structure of a backup automatic switching control device for a diesel generator provided in one embodiment of this application; Figure 4 This is a schematic diagram of the structure of a terminal device provided in an embodiment of this application. Detailed Implementation

[0020] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0021] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0022] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0023] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0024] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0026] When the mains power grid experiences an anomaly, the backup diesel generator can be started as an emergency backup power source to output electrical energy and ensure continuous power supply to the user side. "Automatic backup power connection" refers to the control logic that automatically switches to backup diesel generator power supply after the mains power supply fails or malfunctions.

[0027] The existing automatic transfer switching control methods for diesel generators have the following inherent technical defects in practical engineering applications, which have long restricted the reliability of emergency power supply, such as: First, the fault diagnosis accuracy is extremely low, leading to frequent false trips and failures to trip. Traditional single voltage and frequency discrimination modes cannot distinguish between different power grid conditions such as instantaneous harmonic disturbances, short-term voltage fluctuations, instantaneous voltage drops, permanent power outages, and line short circuits. Even minor power grid disturbances can easily trigger the diesel generator to start as a backup power source, resulting in frequent equipment starts and stops and wasted resources. Furthermore, during actual mains power faults, load surges and parameter fluctuations can easily cause fault diagnosis failures, leading to backup power failures and potentially causing power outages to critical loads.

[0028] Second, the switching logic is rigid, resulting in extremely poor adaptability to different operating conditions. Existing automatic transfer control methods for diesel generators mostly employ fixed switching delays and fixed action sequences, making them unsuitable for complex and varied operating conditions such as light loads, heavy loads, bus faults, line short circuits, and multi-power source coordination. In light load scenarios, fixed long-delay switching can lead to the shutdown of critical equipment; in heavy load scenarios, instantaneous switching can easily cause load-bearing shocks to the diesel generator and sudden drops in voltage and frequency; and in multi-bus tie, multi-incoming-line distribution scenarios, safety hazards such as disordered switching action sequence, circulating power supply current, and accidental closing can easily occur.

[0029] Third, there is no fault-tolerant backup mechanism, and the risk of failure is uncontrollable. Most existing diesel generator backup automatic transfer control methods are single-action mechanisms, performing only one start-up and switching action. If problems such as diesel generator start-up jamming, switch mechanism failure, abnormal signal transmission, or transient interference occur, the system directly determines that the backup action has failed after the initial backup action fails. There is no fault self-check, secondary retry, fault isolation, or backup action capability, which directly causes emergency power outages and cannot meet the redundancy guarantee requirements of high-reliability power supply scenarios.

[0030] Fourth, the control linkage is weak, and there is no closed-loop management capability. The existing automatic transfer control method for diesel generators only independently collects mains electrical parameters, without linking core data such as circuit breaker position status, diesel generator preheating standby status, line fault signals, and real-time load parameters. This results in technical loopholes such as misjudgment of mains power restoration, erroneous opening and closing under load, blind switching without synchronization, and repeated switching of faulty circuits. The system's safety and stability cannot meet the power supply requirements of high-end precision loads and core infrastructure.

[0031] In summary, existing automatic backup control methods for diesel generators suffer from technical shortcomings such as one-sided criteria, fixed timing, lack of fault tolerance redundancy, and lack of closed-loop linkage. There is an urgent need for a multi-dimensional discrimination, adaptive regulation, fault tolerance fallback, and full-state closed-loop automatic backup control method.

[0032] In response, this application provides a method for automatic backup power supply control of diesel generators, which is applicable to the automatic switching control of emergency backup power supply in critical load scenarios such as industrial and mining enterprises, data centers, medical buildings, rail transit, nuclear power, and airports. It can realize accurate fault identification under multiple operating conditions, adaptive timing switching, and fault-tolerant backup power supply, effectively improving the reliability and scenario adaptability of emergency power supply systems.

[0033] Please see Figure 1 , Figure 1 This is a flowchart illustrating a method for automatic backup switching control of a diesel generator according to an embodiment of this application. As an example and not a limitation, this method can be operated on or applied to a terminal device, and the method includes: S11. Obtain multi-dimensional monitoring data, including mains electrical parameters and line fault signals on the mains power grid side, as well as real-time load condition parameters on the power consumption side.

[0034] S12. Based on the mains electrical parameters and line fault signals, determine the fault condition type on the mains power grid side.

[0035] S13. Based on the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, determine the corresponding automatic transfer control strategy for the diesel generator. The automatic transfer control strategy is used to determine whether to start the diesel generator as a backup power source.

[0036] It should be noted that the automatic transfer switch (ATS) control strategy can be understood as the control rules for determining whether to start the diesel generator as a backup power source. For example, this ATS control strategy may include whether the diesel generator is started, as well as start-up delay, closing timing, load connection logic, switchback logic after mains power is restored, and fault lockout conditions.

[0037] Multi-dimensional monitoring data can be understood as various types of sensor or data acquisition data collected from two different locations: the power grid side and the power consumption side. Collecting multi-dimensional monitoring data enables comprehensive state perception, allowing for judgment of operating conditions without relying on a single signal.

[0038] The grid side refers to the side of the municipal public power supply network, i.e., the external power input end (grid incoming end). The consumer side, or load side, refers to the back end of the grid, the side where the electrical equipment is located, and is the collective term for all power-consuming loads (such as factory equipment, data center servers, elevators, lighting, and other terminal loads). Mains electrical parameters can be understood as electrical quantity signals collected from the grid incoming line, used to determine the power supply quality. Mains electrical parameters may include: three-phase voltage, three-phase current, frequency, phase, power, voltage fluctuation, frequency fluctuation, etc. Line fault signals can be understood as switch alarm signals uploaded by switches and protection devices, such as: overvoltage alarm, undervoltage alarm, loss of voltage signal, short circuit fault, ground fault, switch trip signal, line break alarm, etc. Real-time load condition parameters can be understood as load data collected in real time on the consumer side, used to reflect the load condition, such as load rate, real-time active power, reactive power, load capacity, proportion of important loads, load switching status, load fluctuation trend, etc.

[0039] Fault condition types refer to the classification and definition of various abnormal scenarios on the mains power grid side, such as transient disturbance faults, short-term voltage drop faults, and permanent power outage faults.

[0040] Specifically, firstly, two monitoring data sources are collected simultaneously: continuous mains electrical parameters (electrical quantities) and fault alarm signals reported by protection devices from the mains power grid side, and operating data of all current electrical loads from the power consumption side, achieving synchronous perception of the grid status and load status. It should be understood that existing diesel generator automatic transfer switch control methods, relying solely on voltage values, are prone to malfunctions, and relying solely on grid status can lead to blindly starting the diesel generator. In this embodiment, by synchronously perceiving the grid status and load status and fusing multi-source information, misjudgments based on a single signal can be avoided, improving the accuracy of operating condition identification.

[0041] Secondly, based on the mains electrical parameters and line fault signals, logical discrimination is performed to classify the current fault condition type on the mains power grid side. For example, a sudden voltage drop or a fault signal that is reported momentarily and then disappears can be identified as a transient disturbance fault. This step provides the first layer of judgment for whether or not to start the diesel generator.

[0042] Finally, based on the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, the corresponding automatic transfer switch control strategy is output according to the preset matching relationship. In this step, the automatic transfer switch control strategy can flexibly adapt to different scenarios, and can dynamically adjust the control logic according to the severity of the fault and the load size to achieve differentiated and precise switching, taking into account both the speed of switching and the safety of equipment operation, and solving the blind spots of traditional logic condition adaptation.

[0043] It is understood that this application provides a method for automatic transfer switching control of a diesel generator, comprising: first, acquiring multi-dimensional monitoring data, including mains electrical parameters and line fault signals on the mains power grid side, and real-time load condition parameters on the power consumption side. Then, based on the mains electrical parameters and line fault signals, determining the fault condition type on the mains power grid side. Finally, according to the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, determining a corresponding automatic transfer switching control strategy for the diesel generator, wherein the automatic transfer switching control strategy is used to determine whether to start the diesel generator as a backup power source. This method, by acquiring electrical analog quantities and line fault signals on the mains power grid side, achieves refined classification of power grid faults, overcoming the problems of malfunction and false start caused by a single monitoring signal.

[0044] Meanwhile, by integrating real-time load condition parameters from the power consumption side into the backup power supply decision-making process, the system no longer relies solely on a single threshold for judging the grid status, thus achieving linkage control between fault condition types and load demand. Furthermore, by matching differentiated backup automatic transfer control strategies for different fault condition types, and distinguishing between transient disturbances and permanent faults, the system can reduce unnecessary start-ups and shutdowns of diesel generators, lower maintenance costs and equipment losses, and also balance power supply reliability with unit operating economy.

[0045] In one possible implementation, the mains electrical parameters on the mains grid side include mains voltage fluctuation value, mains frequency fluctuation value, mains voltage value, and mains frequency value.

[0046] Based on mains electrical parameters and line fault signals, determine the fault condition type on the mains power grid side, including: If the mains voltage fluctuation value and the mains frequency fluctuation value meet the first-level disturbance threshold condition, the first duration is less than the first preset duration, and there is no line fault signal, the fault condition type on the mains grid side is determined to be an instantaneous disturbance fault; wherein, the first duration is used to characterize the duration for which the mains voltage fluctuation value and the mains frequency fluctuation value meet the first-level disturbance threshold condition; When the mains voltage value is within the second-level voltage drop range, the mains frequency value is within the preset frequency range, the second duration is between the first preset duration and the second preset duration, and there is no line fault signal, the fault condition type on the mains grid side is determined to be a short-time voltage drop fault; wherein, the second duration is used to characterize the duration for which the mains voltage value is within the second-level voltage drop range and the mains frequency value is within the preset frequency range; If the mains voltage is less than the secondary voltage drop range, the mains frequency exceeds the preset frequency range, and the third duration is greater than the second preset duration, or if any one of the following is present: a line fault signal, a bus fault signal, or an upstream switch tripping signal, the fault condition type on the mains grid side is determined to be a permanent power outage fault; wherein, the third duration is used to characterize the duration for which the mains voltage is less than the secondary voltage drop range and the mains frequency exceeds the preset frequency range.

[0047] It should be noted that the mains voltage value refers to the real-time effective voltage value (three-phase phase voltage or line voltage) collected from the incoming power grid, serving as the basic analog quantity for judging the amplitude of power supply from the grid. The mains voltage fluctuation value refers to the difference between the maximum and minimum mains voltage values ​​over a period of time, i.e., the voltage fluctuation rate, characterizing the degree of dynamic voltage oscillation. The mains frequency value refers to the real-time frequency of the AC mains power supply (standard frequency value is 50Hz). The mains frequency fluctuation value refers to the maximum frequency deviation over a period of time, characterizing the amplitude of grid frequency oscillation.

[0048] The first-level disturbance threshold condition can be understood as a pre-set upper limit threshold for voltage and frequency fluctuations, used to identify minor and transient grid oscillations. The first duration can be understood as the continuous duration for which the mains voltage and frequency fluctuation values ​​remain stable under the first-level disturbance threshold condition. The first preset duration is a pre-set time value. Transient disturbance faults refer to brief and minor oscillations in the power grid without hardware line faults. In this case, the power grid has self-recovery capabilities, such as short-term fluctuations caused by the starting of large motors.

[0049] The second voltage drop range can be understood as a pre-set voltage drop range, representing a moderate voltage dip where the voltage has not completely disappeared and remains above the undervoltage threshold. The preset frequency range can be understood as the frequency range allowed by normal power supply (e.g., 49Hz to 51Hz), within which the frequency has not deviated significantly. The second duration can be understood as the continuous duration during which the mains voltage value remains stable within the second voltage drop range while the mains frequency value remains within the preset frequency range.

[0050] The second preset duration refers to a pre-configured time used to distinguish between short-term voltage drops and persistent faults. A short-term voltage drop fault refers to a moderate voltage drop with a relatively normal frequency, lasting for a limited period of time, and is considered a moderate power grid anomaly.

[0051] The third duration can be understood as the continuous duration during which the mains voltage value is lower than the secondary voltage drop range and the mains frequency value exceeds the normal frequency range. Bus fault signal refers to the switch alarm signal generated by a short circuit, grounding, or other fault on the distribution bus. Upper-level switch trip signal refers to the hard-contact signal of the incoming switch at the front end of the power grid or the upper-level distribution protection switch tripping, indicating that the upper-level power supply circuit is disconnected. Permanent power outage fault refers to a continuous and severe power supply anomaly in the power grid, or a hardware circuit failure or switch disconnection, where the power grid cannot restore power on its own and a backup power source needs to be activated.

[0052] In this embodiment, the traditional single threshold discrimination method is abandoned, and a three-level fault classification discrimination model is established. The fault condition type is determined by multi-parameter fusion. The specific discrimination rules are as follows: 1) Real-time monitoring of mains voltage and frequency fluctuations. When the mains voltage and frequency fluctuations reach the first-level disturbance threshold (e.g., mains voltage fluctuation ≤ 15% of rated voltage, mains frequency fluctuation ≤ ±0.5Hz), the first duration is less than the first preset duration (e.g., first duration < 100ms), and no line fault switch signal is received, the current fault condition on the mains grid side can be determined as a transient disturbance fault. For example, grid oscillations caused by the start-up and shutdown of nearby high-power equipment, where the line itself is fault-free, will recover on its own within a short time. In this step, pure electrical fluctuations are distinguished from actual line hardware faults. When no fault signal is received, serious problems such as short circuits and open circuits are excluded. Minor grid oscillations are classified separately and not identified as serious power outage faults. Transient disturbances are extremely short-lived, requiring no backup power supply, preventing frequent start-up and shutdown of units from causing mechanical wear and fuel waste.

[0053] 2) When the mains voltage drops to a moderate voltage drop range (i.e., the secondary voltage drop range, indicating no complete power loss, such as a mains voltage of 60%-85% of the rated voltage), and the mains frequency remains within the acceptable range (preset frequency range, such as 49Hz-51Hz), without frequency collapse, and the duration of this abnormal state (i.e., the second duration) falls between the first and second preset durations (e.g., the second duration is between 100ms and 500ms), and there is no line fault alarm signal, the current fault condition on the mains grid side can be determined as a short-term voltage drop fault. For example, a sudden increase in grid load causes a short-term voltage drop, which can slowly recover after a period of time. In this step, by introducing the duration dimension for judgment, extremely short-term voltage spikes are filtered out, preventing instantaneous voltage peaks from being misjudged as voltage drop faults. Relying on multi-condition joint judgment, compared with single voltage threshold judgment, the probability of misjudgment can be significantly reduced.

[0054] 3) When the mains voltage drop exceeds the secondary voltage drop range (e.g., mains voltage < 60% of rated voltage, complete voltage loss), the mains frequency deviates from the preset frequency range, and the duration of this severe anomaly (i.e., the third duration) exceeds the second preset duration range (e.g., the third duration ≥ 500ms); or, when any one of the following fault signals is received (i.e., a line fault signal, a bus fault signal, or an upstream switch trip signal), the current mains power grid fault condition can be determined to be a permanent power outage fault. In this step, on the one hand, continuous electrical quantities are used to judge prolonged severe instability; on the other hand, the tripping of the protection device and the fault hard signal are directly accepted. These two types of information complement each other. Once a permanent power outage fault is determined, it means that the mains power cannot be restored on its own, and the prerequisite for starting the diesel generator for automatic transfer is met.

[0055] It should be understood that in this embodiment, by combining mains electrical parameters and line fault signals, the fault condition type on the mains power grid side (i.e., transient disturbance fault, short-term voltage drop fault, and permanent power outage fault) is determined, replacing the traditional simple binary judgment of normal or fault, and realizing a three-level refined classification of power grid faults. Through multi-dimensional cross-verification integrating analog electrical quantities (voltage, frequency, duration) and switching fault signals, misjudgments and missed judgments caused by electromagnetic interference and sampling glitches are effectively suppressed. Simultaneously, differentiated judgment logic is set for different levels of faults to distinguish between self-recoverable grid anomalies and non-self-recoverable permanent power outages, providing accurate input for subsequent differentiated backup automatic transfer control strategies.

[0056] In one possible implementation, the automatic transfer switch control strategy for the diesel generator is determined based on the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, including: When the fault condition type on the mains power grid side is a transient disturbance fault, the automatic transfer switch control strategy is determined to not start the diesel generator, and the mains power grid side maintains its original operating state.

[0057] When the fault condition type on the mains power grid side is a short-time voltage drop fault, the switching delay time is determined based on the real-time load condition parameters on the power consumption side. After waiting for the switching delay time, if the mains power grid side does not return to normal, the automatic transfer switch control strategy is determined to start the diesel generator as a backup power source.

[0058] When the fault condition type on the mains power grid side is a permanent power outage fault, the automatic transfer switch control strategy is determined to start the diesel generator as a backup power source.

[0059] In this embodiment, when the fault condition type on the mains power grid side is identified as a transient disturbance fault, traditional fixed threshold logic is prone to misjudging it as a mains power fault, triggering the diesel generator to start and the ATS to switch, resulting in unnecessary equipment start-ups and shutdowns. In this embodiment, the control logic can be directly locked as follows: do not start the diesel generator, maintain the existing mains power supply circuit unchanged (i.e., the mains power grid side maintains its original operating state), continuously monitor the grid parameters, and wait for the disturbance signal to disappear on its own. Typically, this type of disturbance is caused by the start-up and shutdown of surrounding equipment or short-term impact loads, and its duration is extremely short, allowing the mains power grid to recover quickly. It should be understood that this step can avoid meaningless frequent start-ups and shutdowns of the diesel generator, reduce the impact of unit start-up, mechanical wear, extend the service life of the diesel generator, and adapt to complex industrial harmonic interference scenarios.

[0060] When a short-term voltage drop fault is identified on the mains power grid side, traditional logic uses a uniform fixed delay. Excessive delay under light loads leads to short-term power outages and equipment shutdowns, while instantaneous switching under heavy loads causes load surges in the diesel generator, resulting in a sudden voltage drop. In this implementation, the switching delay duration can be dynamically determined based on real-time load parameters from the power user side. The switching delay duration refers to a pre-set waiting window period for short-term voltage drop faults. For example, a shorter delay can be set when the proportion of critical loads is high and the equipment's power outage tolerance time is short; a longer delay can be set when the load is mainly non-critical and short-term power outages are permissible. In some examples, a 500ms switching delay is automatically matched for light-load conditions, and a 1.5s switching delay is automatically matched for heavy-load conditions.

[0061] During this waiting window (i.e., the switching delay period), the diesel generator is not started. Instead, the status of the mains power grid is continuously monitored. After the switching delay period, the status of the mains power grid is checked again to see if it has self-healed. If the mains power grid has returned to normal, starting the diesel generator is abandoned. If the mains power grid is still abnormal (has not returned to normal), a command is issued to start the diesel generator, which is then put into operation as a backup power source. It should be understood that this step, by introducing a dynamic adaptation of the switching delay period to the load condition, differs from the traditional fixed delay scheme. It takes into account both the possibility of grid self-healing and the stability of load power supply, ensuring rapid recovery under light loads and avoiding equipment impact under heavy loads, thus solving the problem of poor adaptability of traditional fixed timing schemes.

[0062] When a permanent power outage is identified as a fault on the mains power grid side, the grid cannot recover autonomously. Traditional logic relies solely on voltage determination, making it susceptible to short-circuit parameter fluctuations, which can lead to failure to operate or blindly closing the circuit breaker, causing the short-circuit fault to escalate. In this embodiment, no waiting delay is required; the backup power supply logic is executed directly, starting the diesel generator and using it as a backup power source. It should be understood that this step, for permanent power outages such as short circuits and tripping of upstream switches, directly executes the backup power supply logic, achieving rapid response, meeting emergency power supply specifications, preventing production and equipment losses due to prolonged power outages, and completely eliminating the risk of fault escalation.

[0063] It should be understood that in this embodiment, by adopting a hierarchical control strategy for three types of power grid faults, namely, prohibiting startup for minor disturbances, delaying and waiting for moderate faults, and starting immediately for severe faults, the traditional single mode of starting the diesel generator as soon as a fault occurs is broken.

[0064] In one possible implementation, after determining that the automatic transfer switch (ATS) strategy is to start the diesel generator as a backup power source, the method includes: The start-up readiness status and circuit breaker mechanism status of the diesel generator are verified. The start-up readiness status of the diesel generator includes the diesel generator preheating status, battery voltage status, and diesel generator set fault status.

[0065] If the start-up readiness status of the diesel generator and the status of the circuit breaker mechanism are both normal, then the diesel generator is started. After the diesel generator has started and the output voltage and frequency values ​​of the diesel generator meet the preset grid connection conditions, the corresponding switching control action is executed according to the real-time load condition parameters of the power consumption side.

[0066] If the start-up readiness status of the diesel generator and / or the status of the circuit breaker mechanism are found to be abnormal, a fault-tolerant self-test is performed.

[0067] It should be noted that when the diesel generator is not preheated, in a fault-locked state, or the circuit breaker is stuck or in an abnormal position, even if it is determined that there is a fault in the mains power grid and backup power needs to be activated, the equipment status self-check of the diesel generator should be performed first, and the backup power should be activated only after the equipment abnormality is ruled out, so as to prevent invalid actions.

[0068] Specifically, after determining that the automatic transfer switch control strategy is to start the diesel generator as a backup power source, before issuing the diesel generator start command, it is necessary to collect the start-ready status signal of the diesel generator and the status signal of the relevant circuit breaker mechanism to verify the preconditions for starting the diesel generator.

[0069] The start-ready state of a diesel generator can be understood as the set of prerequisites that enable the diesel generator to receive start commands, start reliably, and operate normally under load. These start-ready conditions are the preconditions for issuing start commands to the diesel generator. These start-ready conditions can include the following three states: diesel generator preheating state, battery voltage state, and diesel generator set fault state.

[0070] The preheating state of a diesel generator refers to the preheating condition of the engine in the generator set. For example, for water-cooled generators, this is reflected in the coolant temperature, and for air-cooled generators, it is reflected in the engine block temperature. In low-temperature environments, the generator set needs preheating; starting directly at excessively low temperatures can easily lead to starting failure and accelerated wear. The start-ready state indicates that the diesel generator's preheating temperature has reached the allowable starting threshold. The battery voltage state refers to the terminal voltage of the diesel generator's starting battery. The battery supplies power to the starter motor and control circuit; excessively low voltage will cause the starter motor to be weak, failing to ignite and start the engine. The start-ready state indicates that the battery voltage is within the normal operating range. The fault state of the diesel generator set refers to the collection of fault alarm signals from the generator set itself (such as overspeed, low oil pressure, high water temperature, insufficient fuel, etc.). The start-ready state indicates that there are no valid fault alarms and no start-locking faults in the generator set.

[0071] The circuit breaker mechanism status can be understood as the working status of the relevant switch bodies, such as the diesel generator output circuit breaker, incoming line circuit breaker, and bus tie circuit breaker. The circuit breaker mechanism status may include: open / close position signals, energy storage status, mechanism faults, spring energy storage, and interlocking signals.

[0072] If all preconditions for starting the diesel generator are verified to be normal (i.e., the generator's start-ready status and circuit breaker mechanism status are both verified to be normal), a start command for the diesel generator is output to start it. After the generator starts, the output voltage and frequency values ​​are continuously collected. If the output voltage and frequency values ​​consistently meet the preset grid connection conditions, the generator can be considered to have successfully built up voltage. The preset grid connection conditions refer to the mandatory combination of electrical parameter thresholds on the generator side that must be met before closing the generator's output switch and connecting it to the distribution bus for load connection after the generator has started and built up voltage. These preset grid connection conditions are mandatory access conditions for the diesel generator to connect to the load bus. The core of these conditions is the generator's output voltage and frequency thresholds. Phase, phase sequence, and voltage / frequency difference constraints can be selected according to the scenario to prevent asynchronous closing and inrush current damage to the generator unit and electrical equipment.

[0073] At this point, real-time load condition parameters from the power consumption side (such as load size, load importance, and impact load characteristics) are read, and the corresponding switching control action is selected based on these parameters. The switching control action refers to the combination of opening and closing operations of the distribution circuit breaker. For example, under light load conditions, the circuit breaker can be closed directly to handle the entire load at once; under heavy load conditions, the important load is connected first, followed by the secondary load, and so on.

[0074] In cases where the diesel generator's readiness is abnormal (e.g., insufficient preheating, low battery voltage, or a fault alarm in the unit) or the circuit breaker mechanism is malfunctioning, the diesel generator will not be started; instead, the system will directly jump to the fault-tolerant self-check process. The fault-tolerant self-check process refers to the fault-tolerant handling procedures initiated when pre-verification conditions are not met, including fault diagnosis, status verification, and alarm output. This fault-tolerant self-check process has fault identification, information uploading, and retry capability capabilities, which can improve system reliability.

[0075] It should be understood that in this embodiment, by adding a two-layer pre-condition verification before the diesel generator backup operation is executed, condition checks are carried out from two dimensions: the operating condition of the generator body and the hardware of the switching mechanism. This can intercept scenarios that do not meet the backup conditions in advance, avoid backup failure, reduce the risk of power outage, and improve the reliability of the diesel generator backup power supply system.

[0076] In one possible implementation, after the diesel generator has started and its output voltage and frequency values ​​meet preset grid connection conditions, corresponding switching control actions are executed based on real-time load parameters from the power consumer side, including: When the load rate is in the first preset range in the real-time load condition parameters on the power consumption side, the direct switching control action is triggered to control the switch to close and connect to the backup power supply.

[0077] When the load rate is in the second preset range in the real-time load condition parameters on the power consumption side, a graded and step-by-step switching control action is triggered to gradually switch on the loads supplied by the backup power supply according to the preset timing and load priority.

[0078] The load factor refers to the ratio of the real-time total active power of the electricity user to the rated active power of the diesel generator. This load factor is a core indicator characterizing the load-bearing capacity of the diesel generator and can be used to determine whether there is an overload risk when the load is switched on. The first preset range is a pre-set load factor threshold range, generally a lower range. When the load factor is within this first preset range, the entire load can be switched on at once without causing the diesel generator to overload or the frequency / voltage drop to exceed the allowable range.

[0079] The second preset range is a pre-set load rate threshold range that is higher than the first preset range. When the load rate is within the second preset range, if the entire load is put into operation at once, the impact load and steady-state load can easily cause the diesel generator to be overloaded for a short time, resulting in a sudden drop in voltage and frequency, and in severe cases, it may even trigger the diesel generator protection to trip.

[0080] The tiered and step-by-step load switching control can be understood as a control method that does not connect all loads at once, but connects loads in multiple stages according to predetermined rules. Preset timing refers to the pre-defined time intervals between the connection of different load levels. This allows response time for the diesel generator's speed and voltage regulation system; after each batch of loads is connected, the system waits for the generator's voltage and frequency to stabilize before connecting the next batch, suppressing cumulative impacts. Load priority refers to the classification of electrical loads. High-priority loads are important loads that cannot be disconnected for extended periods and are connected first; low-priority loads are secondary loads that can be connected later and, if necessary, permanently disconnected.

[0081] Specifically, when the load rate is within the first preset range, it is estimated that the simultaneous activation of all loads will not exceed the diesel generator's carrying capacity and will not cause severe voltage or frequency fluctuations. At this time, the faulty main power supply incoming circuit breaker is disconnected, and the diesel generator output switch is directly closed, allowing all target loads to be connected to the diesel generator's backup power supply at once.

[0082] When the load rate is within the second preset range, a one-time full-load connection will generate a significant active power surge, causing fluctuations in diesel generator speed and voltage drops. In this situation, loads are prioritized, with important loads connected first and secondary loads connected later. Then, according to a preset timing sequence, closing commands are issued in batches. That is, after connecting one batch of loads, a preset time is waited until the diesel generator voltage and frequency stabilize before connecting the next batch of loads, gradually completing the connection of all permissible loads. This disperses the inrush current and power generated by load connection, preventing frequency collapse and voltage instability in the diesel generator due to sudden load increases, and preventing the diesel generator protection system from tripping and shutting down.

[0083] It should also be noted that in multi-bus tie and multi-incoming-line distribution topology scenarios, the operating sequence of incoming line switches and bus tie switches can be matched to avoid parallel circulating current and the risk of closing with faults.

[0084] In one possible implementation, after the diesel generator has started and its output voltage and frequency values ​​meet preset grid connection conditions, the method includes the following steps after executing the corresponding switching control action based on the real-time load condition parameters on the power consumption side: Real-time monitoring of the restored voltage and frequency values ​​on the mains power grid side.

[0085] If the restored voltage value is within the allowable range of the rated voltage, the restored frequency value is within the allowable range of the rated frequency, and the fourth duration of the restored voltage value and the restored frequency value is greater than the preset restoration duration, then the mains power grid side is determined to be truly restored.

[0086] After the diesel generator is put into standby mode, the bus voltage, load status, and switch operation status of the mains power grid are monitored in real time. Stability verification is carried out after standby mode is performed, and the power supply stability is continuously verified. That is, the recovery voltage and recovery frequency values ​​of the mains power are monitored in real time to monitor the recovery status of the mains power.

[0087] The restored voltage value is the instantaneous effective value of the three-phase line voltage or phase voltage on the incoming mains power line, which can characterize the actual voltage amplitude after the grid voltage recovers. The restored frequency value is the real-time frequency of the AC power on the incoming mains power line, which can characterize the actual frequency value after the grid voltage recovers.

[0088] The rated voltage allowable range refers to the acceptable range of grid voltage preset according to the power distribution specifications, with the rated voltage as the benchmark for fluctuation limits. For example, the rated voltage allowable range is 0.9UN-1.05UN (UN is the system rated voltage). When the restored voltage value is within the rated voltage allowable range, it is judged that the voltage amplitude is qualified. If the voltage is too high or too low, it is judged that the grid has not restored normally.

[0089] The rated frequency allowable range refers to the acceptable threshold range of the power frequency. For example, the rated frequency allowable range can be 49.5Hz-50.5Hz. If the rated frequency allowable range is exceeded, it means that the power grid is not stable, there is power grid disturbance, low frequency or high frequency fault, and the power grid is judged to have not been restored normally.

[0090] The fourth duration refers to the duration during which the restored voltage and frequency values ​​simultaneously meet their respective rated allowable ranges (qualified ranges), i.e., the continuous compliance time value. The preset recovery duration is a pre-set grid steady-state confirmation delay threshold, which can be used to filter false power restoration signals such as instantaneous voltage flicker, short-term power restoration, and closing impulse pulses (for example, the preset recovery duration can be set to 2s~5s).

[0091] In this embodiment, a delayed confirmation mechanism is adopted. When the restored voltage value on the mains power grid side is within the rated voltage allowable range, the restored frequency value is within the rated frequency allowable range, and the fourth duration of the above two qualified states is longer than the preset recovery duration (e.g., 2 seconds), the mains power grid side is determined to be truly restored. Load switching and unit shutdown reset are then performed to avoid false resets due to instantaneous restoration, thus improving the reliability of the judgment. A true restoration on the mains power grid side means that the mains power incoming voltage and frequency are stable at qualified operating conditions for a long period of time, the grid fault is completely eliminated, and the grid is ready to resume operation as the main power source. This is different from temporary false power states such as instantaneous voltage flashover, instantaneous power restoration, and maintenance test power supply.

[0092] In some examples, during emergency power supply from a diesel generator under load, the mains power momentarily recovers and then drops again before eventually stabilizing and returning to normal voltage and frequency. Traditional logic would trigger a revert to a reset upon this momentary recovery, leading to frequent system switching, power supply oscillations, and equipment damage. However, in this embodiment, by continuously monitoring mains parameters, a true recovery is only considered complete when the recovered voltage and frequency values ​​remain stable for a fourth consecutive duration (e.g., ≥2 seconds). Only then is a smooth load revert to a reset and the diesel generator shut down, filtering out the illusion of a momentary recovery. This eliminates frequent false resets caused by mains power fluctuations, ensuring power supply stability and equipment safety.

[0093] In one possible implementation, if the start-up readiness status of the diesel generator and / or the circuit breaker mechanism status are found to be abnormal, a fault-tolerant self-test is performed, including: If the diesel generator's start-up readiness status is abnormal, a second start command will be issued after a first preset delay.

[0094] If the diesel generator is in a normal start-up ready state, but the circuit breaker mechanism is in an abnormal state, then the circuit breaker mechanism is isolated and the standby circuit breaker mechanism is called to complete the load power supply.

[0095] If the diesel generator's start-up readiness status and the circuit breaker mechanism status are both abnormal, and all conventional backup power supply procedures fail, then the simplest emergency switching procedure will be executed to force the backup power supply to be put into operation.

[0096] It should be noted that fault-tolerant self-checking can be understood as follows: after detecting an anomaly in the pre-condition verification, it does not directly lock out the entire backup circuit or immediately trigger an alarm shutdown. Instead, it employs a multi-level fault handling logic involving fault differentiation, retry startup, equipment redundancy switching, and emergency backup switching. This multi-level fault handling logic identifies the fault, attempts to repair it, and provides a backup redundancy switch. This fault-tolerant self-checking can resolve power supply failures directly caused by single-point faults in the backup system.

[0097] The first preset duration is a pre-defined delay waiting time. This timeframe is reserved for fault self-healing in cases of abnormal diesel generator readiness, allowing for unit temperature recovery, battery voltage recovery, and reset of momentary fault signals, preventing a direct determination of unit failure due to a momentary fault. For example, the first preset duration could be 3 seconds. The second start command is initiated after the delay following the initial start failure, sending start-up ignition and excitation voltage build-up control signals to the diesel generator control circuit again; this is a fault retry action.

[0098] An abnormal circuit breaker mechanism can be understood as a fault in the diesel generator output switch, incoming switch, bus tie switch, etc., including issues such as uncharged springs, jammed mechanisms, faulty opening and closing coils, and the switch's inability to perform normal opening and closing operations. An isolating circuit breaker mechanism can be understood as electrically and logically isolating a faulty circuit breaker through control circuit interlocking, secondary circuit disconnection, and mechanical interlocking. This shields abnormal signals from the faulty switch, prohibits issuing opening and closing commands to the faulty circuit breaker, and prevents forced operation that could cause mechanism breakage, arcing, short circuits, and secondary equipment damage. A standby circuit breaker mechanism is a redundant backup switchgear in the power distribution system, with the same function as the main circuit breaker. It can replace the faulty main circuit breaker to handle diesel generator grid connection and load switching functions, and is a hardware redundancy backup configuration.

[0099] The standard backup power supply process refers to a standardized, automatic switching process under normal operating conditions, which involves the main diesel generator and main circuit breaker to complete the backup power supply, load transfer, and switching back to the main power supply after the mains power is restored, following a power outage. This process is standard, complete, and operates without fault-tolerant logic such as equipment failure retry, redundant switch switching, or emergency fallback. It serves as the baseline workflow when the system has no hardware anomalies. The simplest emergency switching process abandons conventional logic such as refined status verification, timing control, and load grading. It adopts extremely simple control logic such as hard-contact forced closing, emergency jumper circuits, and direct connection of critical loads. This fallback emergency control strategy prioritizes "restoring power to critical loads," weakening equipment status verification to ensure uninterrupted power supply to core loads.

[0100] This embodiment addresses the lack of fault tolerance and fallback mechanisms in traditional backup power supply systems, proposing a three-tiered fault-tolerant self-checking mechanism encompassing fault-tolerant retry, fault isolation, and fallback backup power supply, covering all abnormal backup power supply failure scenarios. Specifically, during the pre-backup power supply verification process, if any one or both of the following occur—an abnormal diesel generator readiness status, a circuit breaker mechanism malfunction, or both—the normal grid connection switching process is interrupted, and the three-tiered fault-tolerant self-checking logic is entered. This logic is executed independently along three branches, specifically: (1) Level 1 fault tolerance. If the fault source is determined to be only the failure of the diesel generator to meet the start-up readiness status (such as insufficient preheating, low battery voltage, instantaneous fault alarm, etc., resulting in diesel generator start-up failure), and there is no abnormality in the circuit breaker mechanism, a start-up delay time is set to wait for the first preset time (e.g., 3 seconds). Within this first preset time, the low-temperature unit completes preheating, starts the battery with a small amount of power, and the instantaneous fault alarm automatically resets. After the delay ends, the diesel generator start command is re-output, and the diesel generator set is started a second time. If the second start is successful, the normal grid connection switching logic is returned; if the second start still fails, the restart attempt is continued, but a maximum of two restart attempts are performed to eliminate instantaneous signal interference and instantaneous mechanical jamming faults. If the restart still fails after two restart attempts, the diesel generator is determined to have a permanent fault, and the fault alarm is triggered.

[0101] (2) Level 2 fault tolerance. If the diesel generator is in a normal start-up ready state, but the main circuit breaker mechanism is faulty and cannot be closed, the faulty main circuit breaker can be logically isolated, blocking all operating circuits of the faulty main circuit breaker mechanism, shielding the fault feedback signal, and preventing the fault switch from malfunctioning. At this time, the control circuit is switched to the standby circuit breaker. After the diesel generator has built up voltage, the standby circuit breaker is controlled to close, completing the connection of the standby power supply to the load bus, realizing the power supply switch, and prioritizing the power supply to the load.

[0102] (3) Level 3 fault tolerance. If the diesel generator fails to restart, the main circuit breaker and the backup circuit breaker fail, and the conventional backup switching process also fails, the conventional control logic is abandoned, and the simplest emergency switching process is directly started (such as hard-wired emergency circuit, emergency tie switch, emergency bus direct connection, etc.), and the available backup power supply is forcibly connected to the important load bus to realize the power supply backup under extreme working conditions.

[0103] It should be understood that in this embodiment, by accurately classifying the sources of abnormal faults, they are divided into three categories: single unit fault, single circuit breaker fault, and combined unit and circuit breaker faults, which are handled differently. Compared with the unified fault blocking mode, this maximizes the use of intact equipment resources, effectively solves the startup failure caused by instantaneous faults, and achieves zero power supply interruption under extreme conditions through multi-level fault tolerance, thus greatly improving system reliability.

[0104] In one possible implementation, the method further includes: After the fault-tolerant self-check process is completed, fault data is generated, which includes the fault location and fault type.

[0105] It should also be noted that after all fault-tolerant actions are executed, fault data including fault location and fault type will be automatically generated and recorded. The fault circuit will be self-locked and isolated to prevent repeated triggering of abnormal actions and to prevent repeated commissioning of the fault circuit. At the same time, the fault data will be uploaded to provide a basis for operation and maintenance and to realize closed-loop fault handling.

[0106] like Figure 2 As shown, Figure 2 This is a flowchart illustrating a backup automatic switching control method for a diesel generator provided in another embodiment of this application. Figure 2 The specific steps are as follows: Step S21: Real-time acquisition of multi-dimensional parameters. Continuously acquire parameters such as mains electrical parameters, switch status, diesel generator status, load conditions, and line fault signals, achieving millisecond-level data refresh.

[0107] Step S22: Determine the fault condition type. Call the hierarchical discrimination algorithm to distinguish between three types of fault conditions: transient disturbance fault, short-term voltage drop fault, and permanent power failure fault, and output the fault level command.

[0108] Step S23: Match the standby automatic transfer control strategy. Dynamically configure the standby automatic transfer control strategy according to the fault condition type. For example, for transient disturbance faults, lock all standby actions and maintain the original operating state; for short-term voltage drop faults, dynamically adjust the switching delay according to the load size. For example, set the switching delay to 500ms under light load, 1s under normal load, and 1.5s under heavy load, waiting for the grid to heal itself. If the grid does not recover within the time limit, start the standby transfer; for permanent power outage faults, wait with zero redundancy and immediately output the diesel generator start command.

[0109] Step S24: Diesel generator pre-start status verification. In the event of a short-term voltage drop fault or a permanent power outage, after receiving the diesel generator start command, it is necessary to verify the start-ready status of the diesel generator (such as the diesel generator preheating status, battery voltage, and unit fault signal) and the status of the circuit breaker mechanism. If the status is normal, the unit will start; if the status is abnormal, the fault-tolerant self-check mechanism will be triggered immediately.

[0110] Step S25: Adaptive Switching Control. After the unit starts up and the voltage and frequency values ​​meet the standards, differentiated switching is performed according to the load conditions. That is, under light load conditions, the unit is directly and quickly switched on; under heavy load conditions, a slow switching buffer control is implemented to switch on the load in stages and steps to suppress inrush current; under multi-power supply conditions, the timing of the bus tie and incoming line switch action is automatically matched to avoid circulating current and accidental closing.

[0111] Step S26: Closed-loop verification after backup power is put into operation. After backup power is put into operation, the bus voltage, load status, and switch operating status are monitored in real time to conduct post-backup stability verification and continuously verify power supply stability.

[0112] Step S27: Mains power restoration adaptive reset. The mains power restoration status is monitored in real time, and a delayed confirmation mechanism is adopted. If the mains power is stable and meets the standard for more than 2 seconds, it is determined to be a real restoration, and load switching and unit shutdown reset are performed to avoid false reset due to instantaneous restoration.

[0113] Understandably, this application constructs a multi-dimensional, integrated three-level fault discrimination model based on mains electrical parameters, equipment status parameters, and operating condition characteristic parameters. This model accurately distinguishes between instantaneous grid disturbance faults, short-term voltage drop faults, and permanent power outage faults. Combining fault condition types with real-time load conditions, it adaptively and dynamically adjusts the backup switching delay, switch action sequence, and load input strategy. Simultaneously, it establishes a multi-level fault-tolerant mechanism with three levels of fault-tolerant retry, fault self-locking isolation, and emergency backup input, coupled with a five-in-one, full-state closed-loop linkage control system encompassing mains power, switches, diesel generators, loads, and lines, along with a delayed stability reset verification logic. This application addresses the industry pain points of traditional backup logic, such as low discrimination accuracy, weak operating condition adaptability, and lack of redundancy protection. It significantly improves the stability, safety, and reliability of emergency power supply systems. No new hardware is required; only software algorithm upgrades are needed to adapt to various new and old diesel generators' Automatic Transfer Switch (ATS) systems. This approach is highly versatile, has low implementation costs, and high promotional value.

[0114] The automatic switching control method for a diesel generator provided in this application has the following significant technical advancements and beneficial effects compared to the prior art: (1) The accuracy of judgment is greatly improved, solving the problem of false operation and failure to operate. Through multi-dimensional hierarchical judgment algorithm, various power grid operating conditions and fault types are accurately distinguished. The problem of false judgment and missed judgment caused by single parameter judgment is eliminated from the root of the algorithm. The accuracy of backup operation is greatly improved, and it can be adapted to complex industrial scenarios such as harmonic interference and sudden load change.

[0115] (2) Full-condition adaptive adaptation with strong versatility. Through dynamic timing and differentiated switching strategies, it adapts to various operating conditions such as light load, heavy load, short circuit, and multi-power supply topology, solving the problems of rigid traditional logic and poor scenario adaptability. It can be universally adapted to all power distribution emergency power supply scenarios.

[0116] (3) Industry-leading fault tolerance and redundancy capabilities significantly improve power supply reliability. The unique three-level fault tolerance retry + backup investment mechanism fills the gap in the industry's backup fault tolerance technology, completely solves the power outage problem caused by single action failure, and meets the high reliability requirements of nuclear power, data centers and other zero power outage scenarios.

[0117] (4) Zero hardware modification and low implementation cost. This application is a pure logic algorithm and control process innovation. It does not require modification of the existing ATS system and diesel generator hardware. It can be implemented by simply upgrading the program. It is compatible with the modification of old and new equipment and the matching of new machines, and has high promotion value.

[0118] (5) Closed-loop safety management and control to eliminate safety hazards. The full-state linkage closed-loop control effectively avoids safety risks such as closing under load, circulating current, false reset, and repeated connection during faults, and greatly improves the safety and stability of the power distribution system.

[0119] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0120] A backup automatic transfer control method for a diesel generator, corresponding to the above embodiment, Figure 3 The diagram shows a schematic of the automatic switching control device for a diesel generator according to an embodiment of this application. For ease of explanation, only the parts related to the embodiment of this application are shown.

[0121] Reference Figure 3 The automatic backup switching control device 3 for the diesel generator in this embodiment includes: The acquisition module 31 is used to acquire multi-dimensional monitoring data, which includes mains electrical parameters and line fault signals on the mains power grid side, as well as real-time load condition parameters on the power consumption side.

[0122] The identification module 32 is used to determine the fault condition type on the mains power grid side based on the mains electrical parameters and line fault signals.

[0123] The determination module 33 is used to determine the backup automatic transfer control strategy of the diesel generator according to the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side. The backup automatic transfer control strategy is used to determine whether to start the diesel generator as a backup power source.

[0124] Furthermore, the mains electrical parameters on the mains grid side include mains voltage fluctuation value, mains frequency fluctuation value, mains voltage value, and mains frequency value.

[0125] The recognition module 32 includes: The first identification submodule is used to determine the fault condition type of the mains power grid side as an instantaneous disturbance fault when the mains voltage fluctuation value and the mains frequency fluctuation value meet the first-level disturbance threshold condition, the first duration is less than the first preset duration, and there is no line fault signal; wherein, the first duration is used to characterize the duration for which the mains voltage fluctuation value and the mains frequency fluctuation value meet the first-level disturbance threshold condition. The second identification submodule is used to determine the fault condition type of the mains power grid side as a short-time voltage drop fault when the mains voltage value is in the second-level voltage drop range, the mains frequency value is in the preset frequency range, the second duration is between the first preset duration and the second preset duration, and there is no line fault signal; wherein, the second duration is used to characterize the duration for which the mains voltage value is in the second-level voltage drop range and the mains frequency value is in the preset frequency range. The third identification submodule is used to determine the fault condition type of the mains power grid side as a permanent power outage fault when the mains voltage value is less than the secondary voltage drop range, the mains frequency value exceeds the preset frequency range, and the third duration is greater than the second preset duration, or when any one of the following is present: line fault signal, bus fault signal, or upper-level switch trip signal; wherein, the third duration is used to characterize the duration when the mains voltage value is less than the secondary voltage drop range and the mains frequency value exceeds the preset frequency range.

[0126] Furthermore, module 33 includes: The first determination submodule is used to determine the automatic transfer switch control strategy as not starting the diesel generator and maintaining the original operating state of the mains power grid when the fault condition type on the mains power grid side is a transient disturbance fault.

[0127] The second determination submodule is used to determine the switching delay time based on the real-time load condition parameters of the power consumption side when the fault condition type on the mains power grid side is a short-time voltage drop fault. After waiting for the switching delay time, if the mains power grid side has not returned to normal, the backup automatic transfer control strategy is determined to start the diesel generator as a backup power source.

[0128] The third determination submodule is used to determine the automatic transfer switch control strategy to start the diesel generator as a backup power source when the fault condition type on the mains power grid side is a permanent power outage fault.

[0129] Furthermore, the automatic switching control device 3 for the diesel generator includes: The verification module is used to verify the start-up readiness status of the diesel generator and the status of the circuit breaker mechanism. The start-up readiness status of the diesel generator includes the diesel generator preheating status, battery voltage status, and diesel generator set fault status.

[0130] The first control module is used to start the diesel generator if the start-up readiness status of the diesel generator and the status of the circuit breaker mechanism are both normal, and to execute the corresponding switching control action according to the real-time load condition parameters of the power consumption side after the diesel generator has started and the output voltage and frequency values ​​of the diesel generator meet the preset grid connection conditions.

[0131] The second control module is used to perform fault-tolerant self-testing if the start-up readiness status of the diesel generator and / or the status of the circuit breaker mechanism are found to be abnormal.

[0132] Furthermore, the first control module includes: The direct switching unit is used to trigger the direct switching control action when the load rate is in the first preset range in the real-time load condition parameters on the power consumption side, so as to control the switch to close and connect to the backup power supply.

[0133] The step-by-step switching unit is used to trigger a graded step-by-step switching control action when the load rate is in the second preset range in the real-time load condition parameters on the power consumption side, so as to gradually switch on the loads supplied by the backup power supply according to the preset timing and load priority.

[0134] Furthermore, the automatic switching control device 3 for the diesel generator includes: The real-time monitoring module is used to monitor the recovery voltage and recovery frequency values ​​on the mains power grid side in real time.

[0135] The recovery judgment module is used to determine that the mains power grid side has truly recovered when the recovery voltage value is within the rated voltage allowable range, the recovery frequency value is within the rated frequency allowable range, and the third duration of the recovery voltage value and the recovery frequency value is greater than the preset recovery duration.

[0136] Furthermore, the second control module includes: The first self-test unit is used to issue a second start command after a first preset time delay if the start-ready status of the diesel generator is abnormal.

[0137] The second self-test unit is used to isolate the circuit breaker mechanism and call the standby circuit breaker mechanism to complete the load power supply if the diesel generator's start-up readiness status is normal but the circuit breaker mechanism status is abnormal.

[0138] The third self-test unit is used to execute the simplest emergency switching procedure to force the backup power supply to be put into operation if the diesel generator's start-up readiness status and the circuit breaker mechanism status are both abnormal and all conventional backup power supply procedures fail.

[0139] Furthermore, the automatic switching control device 3 for the diesel generator also includes: The fault data generation module is used to generate fault data after the fault-tolerant self-check process is completed. The fault data includes the fault location and fault type.

[0140] It should be noted that the information interaction and execution process between the modules in the above-mentioned diesel generator automatic switching control device 3 are based on the same concept as the method embodiment of this application. For details on their specific functions and technical effects, please refer to the method embodiment section, which will not be repeated here.

[0141] This application also provides a terminal device, such as... Figure 4 As shown, Figure 4 This is a schematic diagram of the structure of a terminal device provided in an embodiment of this application. (Refer to...) Figure 4The terminal device 4 in this embodiment includes a memory 41, a processor 42, and a computer program stored in the memory 41 and executable on the processor 42. When the processor 42 executes the computer program, it implements the steps in the embodiment of the diesel generator automatic switching control method described above.

[0142] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, can implement the steps in the above-described method embodiments.

[0143] This application provides a computer program product that, when run on a mobile terminal, enables the mobile terminal to implement the steps described in the various method embodiments.

[0144] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of this application can be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include at least: any entity or device capable of carrying the computer program code to a photographic device / terminal device, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium. Examples include USB flash drives, portable hard drives, magnetic disks, or optical disks.

[0145] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0146] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0147] In the embodiments provided in this application, it should be understood that the disclosed apparatus / network devices and methods can be implemented in other ways. For example, the apparatus / network device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0148] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0149] The technical features of the various embodiments described above in this application can be combined arbitrarily without conflict. For the sake of brevity, this specification does not describe all possible combinations, but as long as these combinations do not violate the technical spirit of this application, they should all be considered within the scope of this application. Based on the content disclosed in this application, those skilled in the art can reasonably combine, delete, or replace the technical features of the above embodiments according to actual needs, and such modifications and variations all fall within the protection scope of this application.

[0150] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for automatic switching control of a diesel generator, characterized in that, include: Acquire multi-dimensional monitoring data, including mains electrical parameters and line fault signals on the mains power grid side, and real-time load condition parameters on the power consumption side; Based on the mains electrical parameters and the line fault signal, determine the fault condition type on the mains power grid side; Based on the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, a backup automatic transfer control strategy for the diesel generator is determined accordingly. The backup automatic transfer control strategy is used to determine whether to start the diesel generator as a backup power source.

2. The automatic standby control method for a diesel generator as described in claim 1, characterized in that, The mains electrical parameters on the mains grid side include mains voltage fluctuation value, mains frequency fluctuation value, mains voltage value, and mains frequency value; The process of determining the fault condition type on the mains power grid side based on the mains electrical parameters and the line fault signal includes: If the mains voltage fluctuation value and the mains frequency fluctuation value meet the first-level disturbance threshold condition, the first duration is less than the first preset duration, and there is no line fault signal, the fault condition type on the mains grid side is determined to be an instantaneous disturbance fault; wherein, the first duration is used to characterize the duration for which the mains voltage fluctuation value and the mains frequency fluctuation value meet the first-level disturbance threshold condition; When the mains voltage value is in the secondary voltage drop range, the mains frequency value is in the preset frequency range, the second duration is between the first preset duration and the second preset duration, and there is no line fault signal, the fault condition type on the mains grid side is determined to be a short-time voltage drop fault; wherein, the second duration is used to characterize the duration for which the mains voltage value is in the secondary voltage drop range and the mains frequency value is in the preset frequency range; If the mains voltage value is less than the secondary voltage drop range, the mains frequency value exceeds the preset frequency range, and the third duration is greater than the second preset duration, or if any one of the line fault signal, bus fault signal, or upstream switch trip signal exists, the fault condition type on the mains grid side is determined to be a permanent power outage fault; wherein, the third duration is used to characterize the duration for which the mains voltage value is less than the secondary voltage drop range and the mains frequency value exceeds the preset frequency range.

3. The automatic standby control method for a diesel generator as described in claim 2, characterized in that, The step of determining the automatic transfer switch control strategy for the diesel generator based on the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side includes: When the fault condition type on the mains power grid side is the instantaneous disturbance fault, the automatic transfer switch control strategy is determined to not start the diesel generator, and the mains power grid side maintains its original operating state. When the fault condition type on the mains power grid side is the short-time voltage drop fault, the switching delay time is determined according to the real-time load condition parameters on the power consumption side. After waiting for the switching delay time, if the mains power grid side does not return to normal, the automatic transfer switch control strategy is determined to start the diesel generator as a backup power source. When the fault condition type on the mains power grid side is the permanent power outage fault, the automatic transfer switch control strategy is determined to start the diesel generator as a backup power source.

4. The automatic standby control method for a diesel generator as described in claim 3, characterized in that, After determining that the automatic transfer switch control strategy is to start the diesel generator as a backup power source, the method includes: The start-up readiness status and circuit breaker mechanism status of the diesel generator are verified; wherein, the start-up readiness status of the diesel generator includes the diesel generator preheating status, battery voltage status, and diesel generator set fault status. If the start-up readiness status of the diesel generator and the status of the circuit breaker mechanism are both normal, then the diesel generator is started. After the diesel generator has started and the voltage and frequency values ​​output by the diesel generator meet the preset grid connection conditions, the corresponding switching control action is executed according to the real-time load condition parameters of the power consumption side. If the start-up readiness status of the diesel generator and / or the status of the circuit breaker mechanism are found to be abnormal, a fault-tolerant self-test is performed.

5. The automatic standby control method for a diesel generator as described in claim 4, characterized in that, When the diesel generator has started and the voltage and frequency values ​​output by the diesel generator meet the preset grid connection conditions, the corresponding switching control action is executed according to the real-time load condition parameters on the power consumption side, including: When the load rate is in the first preset range in the real-time load condition parameters on the power consumption side, a direct switching control action is triggered to control the switch to close and connect to the backup power supply. When the load rate is in the second preset range in the real-time load condition parameters on the power consumption side, a graded and step-by-step switching control action is triggered to gradually switch on the loads supplied by the backup power supply according to the preset timing and load priority.

6. The automatic standby control method for a diesel generator as described in claim 5, characterized in that, After the diesel generator has started and the voltage and frequency values ​​output by the diesel generator meet the preset grid connection conditions, the method includes the following steps: After executing the corresponding switching control action based on the real-time load condition parameters of the power consumer side, the method includes: Real-time monitoring of the restored voltage and frequency values ​​on the mains power grid side; If the recovery voltage value is within the rated voltage allowable range, the recovery frequency value is within the rated frequency allowable range, and the fourth duration of the recovery voltage value and the recovery frequency value is greater than the preset recovery duration, then the mains power grid side is determined to be truly restored.

7. The automatic standby control method for a diesel generator as described in claim 4, characterized in that, If the start-up readiness status of the diesel generator and / or the status of the circuit breaker mechanism are found to be abnormal, a fault-tolerant self-test is performed, including: If the diesel generator’s start-ready status is abnormal, a second start command will be issued after a first preset delay. If the diesel generator is in a normal start-up ready state, but the circuit breaker mechanism is in an abnormal state, then the circuit breaker mechanism is isolated and the standby circuit breaker mechanism is called to complete the load power supply. If the diesel generator's start-up ready state and the circuit breaker mechanism's state are both abnormal and all conventional backup power supply procedures fail, then the simplest emergency switching procedure will be executed to force the backup power supply to be put into operation.

8. The automatic switching control method for a diesel generator as described in claim 7, characterized in that, The method further includes: After the fault-tolerant self-check process is completed, fault data is generated, which includes the fault location and fault type.

9. A standby automatic transfer control device for a diesel generator, characterized in that, include: The acquisition module is used to acquire multi-dimensional monitoring data, which includes mains electrical parameters and line fault signals on the mains power grid side, as well as real-time load condition parameters on the power consumption side. The identification module is used to determine the fault condition type on the mains power grid side based on the mains electrical parameters and the line fault signal; The determination module is used to determine the backup automatic transfer control strategy of the diesel generator according to the fault condition type on the mains power grid side and the real-time load condition parameters on the power consumption side, wherein the backup automatic transfer control strategy is used to determine whether to start the diesel generator as a backup power source.

10. A terminal device, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the method as claimed in any one of claims 1 to 8.

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