PLC-based generator control method, device, equipment and storage medium

Abstract

This application discloses a PLC-based generator control method, device, equipment, and storage medium, relating to the field of diesel generator technology. The method includes: after receiving a start command, the PLC starts the generator in segments based on the real-time speed from a speed sensor, differentially adjusting the starter motor supply voltage and fuel injection valve pulse width to help the engine reach ignition speed; after the speed enters a preset switching range, the speed governor is pre-synchronized and control is transferred; after switching, the speed is monitored periodically, and if an abnormality occurs, control is immediately rolled back and resumed; during operation, parameters such as water temperature and oil pressure are collected, and trends are analyzed through built-in comparison and bit logic instruction rules to identify fault precursors and intervene in stages. This method solves the problems of coarse start control, insufficient switching fault tolerance, passive fault protection, and the difficulty of predictive protection by low-cost PLCs, effectively improving generator operational reliability and reducing the risk of unplanned downtime.

Description

Technical Field

[0001] This application relates to the field of diesel generator technology, and in particular to a PLC-based generator control method, device, equipment, and storage medium. Background Technology

[0002] As a critical backup power source in the power system, the control performance of diesel generators directly determines the reliability of power supply and the service life of the equipment. In the programmable logic controller (PLC) control schemes for related diesel generators, traditional start-up control often adopts constant voltage power supply or on / off fuel injection modes, failing to adjust control parameters according to the dynamic needs of different physical stages of the start-up process. This easily leads to mechanical shocks and start-up failures. Multi-start-source booster schemes require additional actuators, resulting in high hardware costs and system complexity. Existing start-up-run-free switching schemes only focus on smooth control of the switching process, lacking post-switching effect confirmation and automatic rollback mechanisms for failures. This easily leads to speed instability or even shutdown due to mismatches in the governor's initial commands. Existing fault protection schemes mostly adopt a passive threshold-triggered mode, only acting after a fault occurs. Schemes with trend prediction capabilities have complex algorithms, requiring high-performance computing platforms and cannot run in real-time on low-cost PLCs, making it difficult to achieve fault precursor identification and graded proactive intervention. Summary of the Invention

[0003] This application provides a PLC-based generator control method, device, equipment, and storage medium. It can solve the problems in related technologies, such as large mechanical shocks and low start-up success rates due to coarse start-up control, speed instability or even shutdown due to lack of fault-tolerant recovery mechanisms during mode switching, and passive fault protection where predictive protection algorithms are difficult to implement in real-time on low-cost PLC platforms.

[0004] According to a first aspect of this application, a PLC-based generator control method is provided, comprising:

[0005] After receiving the start command, the PLC controller divides the start process into multiple stages based on the real-time speed obtained from the speed sensor, and executes different control strategies on the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage to assist the engine in reaching the ignition speed. After the real-time speed reaches the preset switching threshold range, the PLC controller performs pre-synchronization control on the speed governor, and when it is determined that the preset switching conditions are met, the engine control is transferred from the PLC controller to the speed governor. During the preset monitoring period after the switch is completed, the PLC controller continuously monitors the real-time speed. If the speed fluctuation or speed drop exceeds the preset allowable range, the switch is determined to have failed, and a rollback operation is immediately performed, and the PLC controller takes over the engine control again. During operation, the PLC controller collects multiple operating parameters in real time, including cooling water temperature, lubricating oil pressure, and fuel pressure. Based on its internally preset deterministic reasoning rules consisting of comparison instructions and bit logic instructions, it performs trend analysis on the rate of change of operating parameters to identify early signs of faults and executes corresponding levels of intervention actions according to the reasoning results.

[0006] According to a second aspect of this application, a PLC-based generator control device is provided, comprising: The control module is configured such that after receiving the start command, the PLC controller divides the start process into multiple stages based on the real-time speed obtained from the speed sensor, and executes different control strategies on the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage to assist the engine in reaching the ignition speed. The handover module is configured such that after the real-time speed reaches the preset switching threshold range, the PLC controller performs pre-synchronization control on the speed governor, and when it is determined that the preset switching conditions are met, the engine control is handed over from the PLC controller to the speed governor. The monitoring module is configured to continuously monitor the real-time speed of the PLC controller during a preset monitoring period after the switch is completed. If the speed fluctuation or speed drop exceeds the preset allowable range, the switch is determined to have failed, and a rollback operation is immediately performed, and the PLC controller takes over the engine control again. The analysis module is configured to collect multiple operating parameters, including cooling water temperature, lubricating oil pressure, and fuel pressure, in real time during the operation of the PLC controller. Based on its internally preset deterministic reasoning rules consisting of comparison instructions and bit logic instructions, it performs trend analysis on the rate of change of operating parameters to identify early signs of faults and executes corresponding levels of intervention actions based on the reasoning results.

[0007] According to a third aspect of this application, an electronic device is provided, comprising: At least one processor; and memory that is communicatively connected to at least one processor; The memory stores instructions that can be executed by at least one processor, which enables the at least one processor to perform the PLC-based generator control method of the first aspect described above.

[0008] According to a fourth aspect of this application, a non-transitory computer-readable storage medium storing computer instructions is provided, wherein the computer instructions are used to cause a computer to execute the PLC-based generator control method of the first aspect described above.

[0009] According to a fifth aspect of this application, a computer program product is provided, including a computer program that, when executed by a processor, implements the PLC-based generator control method as described in the first aspect above.

[0010] This application addresses several key issues in related technologies. By employing a startup control method based on real-time speed-based startup phase division and differentiated control strategies, a smooth handover mechanism with pre-synchronization control and switching condition determination, a fault-tolerant scheme with continuous post-switching status monitoring and automatic rollback for anomalies, and multi-parameter trend analysis and hierarchical intervention logic implemented using PLC built-in comparison instructions and bit logic instructions. These solutions address problems such as large mechanical shocks and low startup success rates due to coarse startup control, speed instability or even shutdowns caused by a lack of fault-tolerant recovery mechanisms during mode switching, and passive fault protection with predictive protection algorithms that are difficult to implement in real-time on low-cost PLC platforms. The goal is to improve generator startup success rate and operational stability, reduce mechanical shocks during equipment startup, ensure the reliability and fault tolerance of mode switching, implement predictive active protection on low-cost PLC platforms, and reduce the risk of unplanned shutdowns.

[0011] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0012] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments 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.

[0013] Figure 1 A schematic flowchart illustrating a PLC-based generator control method provided in an embodiment of this application; Figure 2 This is a schematic diagram of a PLC-based generator control device provided in an embodiment of this application. Detailed Implementation

[0014] The following description, in conjunction with the accompanying drawings, illustrates exemplary embodiments of this application, including various details to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0015] The following description, with reference to the accompanying drawings, describes a PLC-based generator control method, apparatus, device, and storage medium according to embodiments of this application.

[0016] Taking the diesel generator of Siemens CPU226CN PLC as an example, the technical implementation scheme is described in detail below with reference to specific embodiments.

[0017] Figure 1 This is a schematic flowchart of a PLC-based generator control method provided in an embodiment of this application.

[0018] like Figure 1 As shown, the method includes the following steps: Step 101: After receiving the start command, the PLC controller divides the start process into multiple stages based on the real-time speed obtained from the speed sensor, and executes different control strategies on the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage to assist the engine in reaching the ignition speed.

[0019] In some embodiments, the PLC controller uses a Siemens CPU226CN as its core control unit, and a matching magnetoelectric speed sensor is installed on the generator shaft. The output pulse signal is directly connected to the input terminal of the PLC's built-in HSC0 high-speed counter. The PLC uses a high-speed counter with a counting frequency of up to 30kHz to acquire the real-time engine speed using the M / T method. The speed measurement accuracy can reach ±1RPM, providing a reliable speed basis for the stage division and precise control of the startup process.

[0020] After receiving the start command, the PLC controller first performs multi-dimensional logical verification of the pre-start conditions. Only after all verification conditions are met can the start control process begin. The verification conditions include no 86G interlock signal, lubricating oil pressure not lower than 27 PSI, coolant temperature not higher than 96.1℃, no overspeed shutdown signal, fewer than 4 historical start failures, and normal air box status.

[0021] After completing the pre-verification, the PLC divides the starting process into three consecutive characteristic stages based on the real-time collected engine speed. Each stage is matched with a different control strategy, which coordinates the power supply voltage of the starter motor and the injection pulse width of the fuel injection valve to gradually assist the engine in reaching a stable ignition speed.

[0022] The first stage is the static friction overcoming stage, corresponding to the speed range of 0 to 250 RPM. During this stage, the PLC, through its built-in PWM pulse width modulation output, applies a strong excitation voltage of 120% to 130% of the rated voltage to the starter motor within 0.3 to 0.5 seconds, generating peak torque to overcome the static friction resistance of the engine crankshaft. Simultaneously, the PLC controls the fuel injection valve to perform enriched fuel injection with a pulse width of 1.5 to 2 times the idle speed, providing auxiliary power for crankshaft rotation. When the PLC detects that the real-time engine speed first exceeds 10 RPM, it determines that the crankshaft has passed the static friction dead point, immediately ends the strong excitation control, and restores the starter motor supply voltage to 100% of the rated voltage.

[0023] The second stage is the resonance avoidance and acceleration stage, corresponding to the speed range of 250 RPM to 500 RPM. The resonance speed range of this diesel generator set was pre-calibrated to 350 RPM to 400 RPM through bench testing. When the PLC detects that the real-time speed reaches 340 RPM, it executes active torque reduction control, linearly reducing the starter motor supply voltage from 100% to 65%. At the same time, the PLC synchronously adjusts the fuel injection pulse width of the fuel injection valve, linearly increasing it from 1.8 times the idle pulse width to 2.2 times the idle pulse width. By gradually replacing the motor output torque with combustion torque, the engine is driven to quickly pass through the resonance range. During this process, the shaft vibration amplitude is reduced by about 40% compared to the traditional constant pressure starting method.

[0024] The third stage is the ignition assistance stage, corresponding to the speed range of 500 RPM to 700 RPM. When the real-time speed exceeds 500 RPM, the PLC starts the ignition assistance subroutine. Using the crankshaft position sensor, it identifies the top dead center (TDC) of each cylinder's compression stroke. When the piston reaches TDC at a crankshaft angle of 15° to 20°, it outputs a short-duration fuel injection pulse with a pulse width of 30% to 50% of the conventional injection, achieving precise ignition assistance. During this stage, the PLC further reduces the starter motor supply voltage to 30% to 40% of its rated value, providing only auxiliary inertial support. When the engine speed is detected to be consistently above 700 RPM for 2 seconds with a fluctuation rate of less than ±5%, the engine is deemed to have reached a stable ignition speed, completing the start-up control process.

[0025] This step, through multi-stage refined collaborative control based on real-time rotational speed, increases the starting success rate of a single starter motor to over 99% without adding starting hardware. The maximum torque impact during the starting process is reduced by about 35% compared to the traditional constant pressure starting method, and the shaft vibration amplitude is reduced by about 40%. While ensuring starting reliability, it significantly reduces mechanical damage to the engine shaft system during the starting process.

[0026] Step 102: After the real-time speed reaches the preset switching threshold range, the PLC controller performs pre-synchronization control on the speed governor, and when it is determined that the preset switching conditions are met, the engine control is transferred from the PLC controller to the speed governor.

[0027] In some embodiments, the PLC controller continuously collects the real-time engine speed through a built-in high-speed counter. The preset switching threshold range is divided into a pre-synchronization trigger range and a switching execution window. The pre-synchronization trigger range is set to 650 RPM to 690 RPM, and the switching execution window is set to 695 RPM to 705 RPM. When the PLC detects that the engine's real-time speed enters the pre-synchronization trigger range and this speed state remains stable for 2 seconds, it initiates the pre-synchronization control process for the speed governor. The speed governor used in this solution is a 2301A electronic speed governor, a dedicated closed-loop speed control device for diesel generators. It can receive control commands via a 4-20mA analog signal to achieve precise adjustment of the fuel supply.

[0028] During the pre-synchronization control phase, the PLC outputs a 4mA enable signal to the governor via the analog output channel. This signal corresponds to the zero fuel command, causing the governor to enter standby mode. The governor's internal PID controller then starts, tracking the engine's target speed in real time. Simultaneously, the PLC linearly decreases its own fuel control command with a fixed slope, synchronously controlling the governor's internal tracking value to rise linearly. This ensures a smooth transition between the governor's output command and the PLC's fuel control command, eliminating command step differences during subsequent control handover and preventing sudden changes in fuel supply during the switching process.

[0029] During the pre-synchronization control execution process, the PLC continuously monitors the engine's operating status in real time, calculating and verifying the preset switching conditions. The PLC calculates the sliding average speed, instantaneous fluctuation rate, and speed acceleration in real time. The instantaneous fluctuation rate is the ratio of the difference between the maximum and minimum speed values ​​within one second to the average speed value, and the speed acceleration is the change in speed per unit time. The preset switching conditions include three items: the engine's real-time speed enters the switching execution window of 695 RPM to 705 RPM, the instantaneous speed fluctuation rate is less than 3%, and the speed acceleration is less than 20 RPM / s². Only when all three conditions are met simultaneously will the PLC determine that the switching timing is qualified and initiate the control handover process; meeting only one condition will not trigger the switching action.

[0030] The control handover process employs a step-by-step timing control to ensure stability and reliability. First, the PLC instantaneously changes the governor's enable signal from 4mA to the current value corresponding to the current PLC output fuel command. This instantaneous update of the command is achieved through a D / A converter, ensuring the governor's output command perfectly matches the current engine operating requirements. Second, a fixed 20ms delay is set to wait for the governor's actuator to complete its command response and action. Third, the PLC cuts off the starter motor relay's control output and simultaneously sets its own fuel output channel to a high-resistance state, ceasing direct control of the fuel injection valve. Fourth, the PLC sends a mode-switching command to the governor, switching its control mode from tracking mode to automatic control mode, completing the full handover of engine control from the PLC controller to the governor.

[0031] This step achieves smooth pre-synchronization control to smoothly connect the PLC and speed governor control commands, ensures the accuracy of switching timing through joint determination of multi-dimensional switching conditions, and completes the seamless handover of control through step-by-step timing control. Actual testing shows that this solution can control engine speed fluctuation within ±1.5% during switching, with a mode switching success rate of 99.5%. It effectively avoids problems such as sudden speed drops, overshoot, and stalling during switching, significantly improving the smoothness and reliability of diesel generator startup to operating mode switching.

[0032] Step 103: During the preset monitoring period after the switch is completed, the PLC controller continuously monitors the real-time speed. If a speed fluctuation or speed drop is detected that exceeds the preset allowable range, the switch is determined to have failed, and a rollback operation is immediately performed, and the PLC controller takes over engine control again.

[0033] In some embodiments, after the PLC controller completes the handover of engine control to the speed governor, it immediately starts a preset monitoring process. The preset monitoring period is 5 consecutive seconds after the switch is completed. This period is the critical period for initial stability after the speed governor takes over control, and it is also the period when switchover anomalies are most likely to occur.

[0034] During the monitoring period, the PLC continuously collects the pulse signals output by the magnetoelectric speed sensor at a sampling frequency of 30kHz using its built-in HSC0 high-speed counter. It calculates the engine's real-time speed using the M / T method, with the sampling interval synchronized with the PLC's typical 10ms scan cycle to ensure the real-time and continuous nature of the speed data, with no monitoring interruptions. The PLC performs real-time verification of the speed data collected in each scan cycle during the monitoring period. The preset allowable range for speed anomalies is divided into two parts: a speed drop of no more than 50 RPM compared to the stable speed at the time of switching, and a momentary fluctuation rate of no more than 5% within 1 second.

[0035] If the PLC detects that the speed drop exceeds the allowable range, or the speed fluctuation rate exceeds the allowable range, and either condition is met, it immediately determines that the mode switch has failed, terminates the normal monitoring process, and triggers the highest priority interrupt rollback operation. This operation can be executed without waiting for the current scan cycle to end, ensuring the real-time response of the action.

[0036] The rollback operation is executed sequentially according to a fixed timeline. First, the PLC immediately reconnects the control output of the starter motor relay, restoring control authority of the PWM pulse width modulation output channel to provide auxiliary power to the starter motor matching the current speed. Second, the PLC simultaneously restores its direct control authority over the fuel injection valve, taking over the adjustment control of the fuel injection pulse width to ensure that the fuel supply is perfectly matched with the engine's current operating state. Then, the PLC immediately disconnects the governor's automatic control mode, resetting the governor to standby mode and stopping the governor's fuel command output to avoid conflicts between the two sets of control commands. Finally, the PLC drives the horn to emit three short and one long alarm sounds through the horn alarm output channel, simultaneously recording fault data of the switching failure, including the speed, fluctuation rate, and trigger time at the time of the fault, and storing this information in the PLC's register. After the rollback operation is completed, the PLC fully regains control of the engine, and the engine returns to its stable control state before the switchover.

[0037] This step fills the engineering blind spot of existing technologies that only focus on the switching process and lack confirmation of the effect after the switch by setting a fixed monitoring window after the switch. Through clear over-limit judgment logic and millisecond-level response rollback mechanism, automatic recovery can be completed within 1 second after the switch anomaly occurs. The fault tolerance capability of mode switching is improved from zero to full closed-loop coverage. Actual tests have shown that it can reduce the risk of unplanned downtime caused by switching failure to zero, effectively ensuring the stability and reliability of the diesel generator from start-up to operation.

[0038] Step 104: During operation, the PLC controller collects multiple operating parameters in real time, including cooling water temperature, lubricating oil pressure, and fuel pressure. Based on its internally preset deterministic reasoning rules composed of comparison instructions and bit logic instructions, it performs trend analysis on the rate of change of operating parameters to identify fault precursors and executes corresponding level intervention actions according to the reasoning results.

[0039] In some embodiments, the PLC controller uses a Siemens CPU226CN as the core control unit. During the stable operation of the diesel generator, it continuously collects key operating parameters such as cooling water temperature, lubricating oil pressure, and fuel pressure through a matching PT100 temperature sensor and a 4-20mA output pressure sensor, with a fixed sampling period of 1 second. The PLC maintains a cyclic queue with a length of 10 sampling points for each collected parameter, storing real-time parameter data for 10 consecutive seconds. Based on the data from adjacent sampling points, it calculates the instantaneous rate of change of the parameters in real time, providing a stable data foundation for trend analysis and fault identification.

[0040] The PLC has multiple pre-built deterministic inference rules, all built entirely on the PLC's native comparison and bit logic instructions, requiring no complex algorithm models or additional computing units. Each rule produces no more than 50 ladder diagram instructions, with a single rule execution time of less than 0.5ms and a total execution time of less than 3ms. These rules can be executed completely within a single 10ms scan cycle of the PLC. In actual operation, the CPU utilization rate was approximately 65%, leaving ample runtime. The rule base employs multi-parameter joint judgment logic. Specifically, when the coolant temperature rise rate exceeds 0.3℃ / s and the lubricating oil temperature rises synchronously at a rate exceeding 0.2℃ / s, while the ambient temperature is within the normal range of 15℃ to 35℃, it is determined that the radiator efficiency has decreased; when the lubricating oil pressure drop rate exceeds 0.5PSI / s and the oil temperature is within the normal range of 80℃ to 95℃, while the speed fluctuation rate is less than 2%, it is determined that the lubricating oil filter is clogged; when the fuel pressure fluctuation rate exceeds 10% / s and the exhaust temperature fluctuates synchronously, while the speed fluctuation rate exceeds 5%, it is determined that the fuel system is experiencing air intake.

[0041] Within each scan cycle, the PLC cyclically executes preset inference rules based on real-time calculated parameter change rates. Through multi-parameter joint trend comparison, it identifies early signs of equipment failure before parameters reach traditional fault shutdown thresholds, achieving an upgrade from passive threshold protection to proactive trend warning. Based on the fault diagnosis results derived from rule inference, the PLC matches and executes corresponding levels of intervention actions, which are divided into four levels. The first level is the alert level: when the parameter change rate exceeds 70% but does not reach 100% of the threshold, only the fault trend is recorded in the internal register, without triggering an external alarm. The second level is the warning level: upon triggering, an alarm sound is emitted through the output channel, the corresponding fault indicator flashes synchronously, and a command is automatically sent to the speed governor to reduce the engine load by 20%, or a load reduction request is sent to the load distribution control unit. For fuel system intake faults, an exhaust operation is also automatically performed, increasing the fuel supply pressure to 1.2 times and maintaining it for 2 seconds. The third level is the protection level, which executes a controlled shutdown procedure. First, a 200ms trip signal is sent to the generator switch to unload all loads. After a 0.5-second delay, fuel injection is cut off and the intake air damper is closed, completing a smooth shutdown. The fourth level is the emergency level. When overspeed, knocking, or fire signals are detected, all delays are skipped, and tripping, fuel cut-off, and intake air damper closure actions are executed instantaneously. At the same time, the fault state is latched, and any restart attempts are prohibited.

[0042] This solution utilizes lightweight deterministic reasoning rules to achieve early fault detection and tiered proactive intervention on a low-cost PLC platform. It requires no additional high-performance computing equipment, and the hardware cost is only 1 / 5 to 1 / 3 of that of high-end industrial PC solutions. Real-world testing shows that approximately 70% of potential major faults can be proactively intervened for within 30 seconds of occurrence, reducing unplanned engine downtime by 65%. Furthermore, the tiered intervention mechanism minimizes unnecessary shutdowns while ensuring equipment safety, significantly improving the safety and stability of diesel generator operation.

[0043] Compared with related technologies, in this embodiment, after receiving the start command, the PLC controller divides the start-up process into multiple stages based on the real-time speed obtained from the speed sensor. Different control strategies are implemented for the starter motor's power supply voltage and / or the fuel injection valve's injection pulse width in each stage to assist the engine in reaching the ignition speed. Once the real-time speed reaches a preset switching threshold range, the PLC controller performs pre-synchronization control on the governor. When the preset switching conditions are met, engine control is transferred from the PLC controller to the governor. During the preset monitoring period after the switching is completed, the PLC controller continuously monitors the real-time speed. If speed fluctuations or speed drops exceed the preset allowable range, the switching is deemed a failure, and a rollback operation is immediately performed, allowing the PLC controller to regain control of the engine. During operation, the PLC controller collects multiple operating parameters in real-time, including coolant temperature, lubricating oil pressure, and fuel pressure. Based on its internally preset deterministic reasoning rules, composed of comparison instructions and bit logic instructions, it performs trend analysis on the rate of change of operating parameters to identify fault precursors and executes corresponding levels of intervention based on the reasoning results. It can solve the problems in related technologies, such as large mechanical shock and low start-up success rate due to rough start-up control, speed instability or even shutdown due to lack of fault-tolerant recovery mechanism during mode switching, passive fault protection and difficulty in implementing predictive protection algorithms in real time on low-cost PLC platforms. It can achieve the technical effects of improving generator start-up success rate and operational stability, reducing mechanical shock during equipment start-up, ensuring reliability and fault tolerance during mode switching, realizing predictive active protection on low-cost PLC platforms, and reducing the risk of unplanned shutdowns.

[0044] As a specific embodiment of this application, based on the basic scheme, the starting process is further divided into multiple stages according to the real-time speed obtained from the speed sensor, and different control strategies are implemented for the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage, including: When the real-time speed is lower than the first preset threshold, the PLC controller controls the starter motor to run at a strong excitation voltage higher than the rated voltage within the first preset time, and controls the fuel injection valve to inject fuel at a rich pulse width higher than the idle pulse width. When the real-time speed enters the second preset threshold before the preset resonance speed range, the PLC controller controls the power supply voltage of the starter motor to decrease linearly to the first percentage of the rated voltage, and simultaneously controls the fuel injection valve to increase the injection pulse width linearly to the second multiple of the idle pulse width. After the real-time speed exceeds the third preset threshold, the PLC controller controls the power supply voltage of the starter motor to be further reduced to the second percentage of the rated voltage, and when the preset crankshaft angle before the top dead center of the compression stroke is detected, the fuel injection valve is controlled to output a short-term fuel injection pulse.

[0045] Specifically, the PLC controller uses a built-in high-speed counter to collect the pulse signal output by the magnetoelectric speed sensor in real time at a sampling frequency of 30kHz, accurately obtaining the real-time engine speed. Based on the real-time speed, the starting process is divided into three continuous control stages. Each stage is matched with the corresponding starter motor power supply voltage and fuel injection valve injection pulse width coordinated control strategy. All control parameters have been pre-calibrated through diesel generator set bench tests, fully adapting to the mechanical and combustion characteristics of the unit.

[0046] When the real-time speed is lower than the first preset threshold, the PLC controller executes the control strategy for overcoming static friction. The first preset threshold is set at 250 RPM. During this stage, the PLC, through its built-in PWM output channel, controls the starter motor to operate at a strong excitation voltage of 120% to 130% of the rated voltage for a first preset time of 0.3 to 0.5 seconds, generating peak torque to overcome the static friction resistance of the engine crankshaft. Simultaneously, the fuel injection valve is controlled to continuously inject fuel at a enriched pulse width of 1.5 to 2 times the idle pulse width, providing auxiliary power for crankshaft rotation. When the speed is detected to exceed 10 RPM for the first time, it is determined that the crankshaft has passed the static friction dead point, and the strong excitation control is immediately terminated, restoring the starter motor supply voltage to 100% of the rated voltage.

[0047] When the real-time engine speed enters the second preset threshold before the preset resonance speed range, the PLC controller executes the control strategy for the resonance avoidance and acceleration phase. The second preset threshold is calibrated to 340 RPM, and the preset resonance speed range is pre-calibrated to 350 RPM to 400 RPM through bench testing. During this phase, the PLC controller linearly reduces the power supply voltage of the starter motor from 100% of the rated voltage to 65% of the rated voltage, and simultaneously controls the fuel injection pulse width of the fuel injection valve to linearly increase from 1.8 times the idle pulse width to 2.2 times the idle pulse width. By gradually replacing the motor output torque with the combustion torque, the engine is driven to quickly pass through the resonance range.

[0048] When the real-time speed exceeds the third preset threshold, the PLC controller executes the control strategy for the ignition assist and motor disengagement phase. The third preset threshold is set at 500 RPM. During this phase, the PLC controller further reduces the power supply voltage of the starter motor to 30% to 40% of the rated voltage, providing only auxiliary inertial support for the engine. Simultaneously, the crankshaft position sensor identifies the top dead center of each cylinder's compression stroke. When the piston reaches a preset crankshaft rotation angle of 15° to 20° before reaching top dead center, the fuel injection valve is controlled to output a short-duration fuel injection pulse. The pulse width is 30% to 50% of the conventional injection pulse width, achieving precise ignition assist.

[0049] The beneficial effects of this embodiment are that, through phased and precise parameter calibration and coordinated control of the motor-fuel system, the starting success rate of a single starter motor is increased to over 99% without adding any starting hardware. During the starting process, the vibration amplitude of the unit's resonance zone is reduced by about 40% compared to traditional constant pressure starting, and the maximum torque impact is reduced by about 35%, effectively reducing mechanical damage to the engine shaft system during the starting process. At the same time, it avoids the problems of increased hardware costs and system complexity caused by multiple starting source solutions.

[0050] As a specific embodiment of this application, based on the basic scheme, the starting process is further divided into multiple stages according to the real-time speed obtained from the speed sensor, and different control strategies are implemented for the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage, and the method further includes: If the real-time speed does not reach the ignition success threshold within the preset total startup time, the PLC controller determines the cause of the startup failure based on the time consumption and speed change rate of each startup stage, and adjusts the amplitude and duration of the excitation voltage and the pulse width of the short-time fuel injection pulse in the next startup process according to the cause.

[0051] Specifically, while executing the segmented start-up control strategy, the PLC controller simultaneously starts a preset total start-up timer, which is 15 seconds long. The timer begins when the start-up conditions pass multi-dimensional verification and the system officially enters the first stage of control. During the timer, the PLC continuously collects the engine's real-time speed using its built-in high-speed counter. If the real-time speed has not reached the ignition success threshold by the end of the total start-up timer, the start-up is considered a failure. The ignition success threshold is set at 700 RPM, and requires the engine speed to exceed this value for 2 consecutive seconds with a fluctuation rate of less than ±5%. A single instantaneous speed exceeding the threshold is not considered a successful ignition.

[0052] Upon determining a startup failure, the PLC immediately retrieves the time consumption data for each stage of the startup process and the real-time calculated speed change rate data. Through internally preset comparison logic, it accurately pinpoints the specific cause of the startup failure. The failure reasons are categorized into three types, corresponding to the three control stages of startup. The first type is Stage I stall, determined by the engine's real-time speed remaining below 100 RPM within 10 seconds after the end of the forced excitation control. The trigger point for the end of the forced excitation control is the moment the real-time speed first exceeds 10 RPM. The second type is Stage II prolonged resonance, determined by the engine's real-time speed remaining within the preset resonance speed range of 350 RPM to 400 RPM for more than 3 seconds. The third type is Stage III no ignition, determined by the engine's real-time speed fluctuating between 500 RPM and 700 RPM for a sustained fluctuation rate greater than 10% and an acceleration less than 5 RPM / s².

[0053] After identifying the cause of the failure, the PLC will automatically adjust the corresponding control parameters during the next startup process without manual intervention. For stage I stalling, the PLC will increase the amplitude of the forced excitation voltage for the next startup from the upper limit of the range of 120% to 130% of the rated voltage or the current value to 140% of the rated voltage. Simultaneously, the duration of the forced excitation voltage will be extended from the upper limit of the range of 0.3 to 0.5 seconds or the current value to 0.6 seconds to generate greater peak torque and more efficiently overcome potentially increased static friction resistance. For stage III ignition failure, the PLC will increase the pulse width of the short-duration fuel injection pulse in the next startup from the upper limit of the range of 30% to 50% of the conventional injection pulse width or the current value to 60% to 80% to provide a more sufficient amount of ignition fuel and improve the ignition success rate.

[0054] The PLC is configured with four retry opportunities for a failed start-up, with a fixed interval of 10 seconds between each retry. During the interval, the PLC will disconnect the control output of the starter motor and fuel injection valve, waiting for the unit's status to stabilize before re-executing the multi-dimensional verification of start-up conditions and the segmented start-up control process. If all four starts fail, the PLC will issue an alarm signal through the start-up failure output channel and simultaneously latch historical start-up failure data, including the cause of each failure, adjusted control parameters, and speed curves for each stage, for subsequent manual troubleshooting.

[0055] The beneficial effects of this implementation are that by automatically and accurately locating the cause of start-up failure and adaptively adjusting the corresponding control parameters, the next start-up strategy can be optimized in a targeted manner without human experience intervention. Combined with the 4-retry mechanism, the start-up success rate of a single starter motor can be further improved to nearly 100%, which greatly reduces the start-up failure problem caused by mismatch of single start-up parameters and improves the reliability and intelligence level of diesel generator start-up.

[0056] As a specific implementation of this application, based on the basic solution, it further specifies that a rollback operation should be performed immediately, and the PLC controller should take over engine control again, including: Reconnect the starter motor control circuit, restore the PLC controller's control output to the fuel injection valve, and disconnect the governor's automatic control mode to return it to standby mode.

[0057] Specifically, after the PLC controller determines that the mode switching has failed, it immediately triggers an interrupt-type rollback operation with higher priority than the regular cyclic scan task. All control actions can be executed without waiting for the current scan cycle to end, and the total execution time is controlled within 1 second, ensuring millisecond-level response in abnormal engine speed conditions. The rollback operation is executed sequentially according to a preset safety sequence, fundamentally avoiding instruction conflicts between the two control units and preventing further instability of the engine speed.

[0058] The PLC first performs a reconnection operation on the starter motor control circuit. The starter motor control circuit is controlled by the starter motor relay K1 connected to the PLC digital output channel Q0.0. The PLC instantaneously outputs a high-level signal to Q0.0 to reconnect the power supply circuit of relay K1, and simultaneously restores the control authority of the built-in PWM pulse width modulation output channel. Based on the current real-time engine speed, it outputs a duty cycle signal that matches the current speed, providing a power supply voltage of corresponding amplitude to the starter motor, providing stable auxiliary inertial support for the engine, and quickly suppressing the continuous decline in speed.

[0059] Upon reconnecting the starter motor control circuit, the PLC immediately resumes control output to the fuel injection valve. The control terminal of the fuel injection valve is directly connected to the PLC's PWM output channel. The PLC immediately releases the high-resistance setting of the fuel output channel and completely takes over the closed-loop control authority of the fuel injection pulse width. Combining the current engine speed, speed fluctuation rate, and speed acceleration, it outputs a fuel injection pulse width signal that perfectly matches the current operating conditions, ensuring continuous and stable fuel supply and eliminating fuel supply abnormalities caused by governor command mismatch.

[0060] After restoring the above two control permissions, the PLC immediately executes the cut-off and reset operation of the governor control mode. The governor used in this solution is a 2301A electronic governor. The PLC outputs a 4mA basic enable signal to the governor through a 4-20mA analog output channel. This signal corresponds to the zero fuel command. Simultaneously, a mode switching command is sent to the governor, immediately cutting off its automatic control mode, forcibly resetting it to the initial standby state, stopping the governor's independent fuel command output, completely eliminating the risk of conflict between the two sets of control commands from the PLC and the governor, and ensuring the sole ownership of engine control authority.

[0061] The beneficial effects of this implementation are that, through a rigorous three-step rollback operation, it achieves rapid and conflict-free rollback of control authority after a switching failure, filling the engineering blind spot of existing technologies that only focus on the smoothness of the switching process and lack a fault-tolerant recovery mechanism for switching failures. Actual testing shows that this solution can restore the engine to a stable control state within 1 second after a switching anomaly is triggered, completely avoiding speed drops, engine shutdowns, and even unplanned shutdowns caused by mismatched initial governor commands or abnormal actuator responses. It increases the success rate of start-up mode switching from approximately 92% in traditional solutions to 99.5%, significantly improving the reliability and fault tolerance of the entire diesel generator control process.

[0062] As a specific implementation of this application, based on the basic scheme, it further defines a deterministic inference rule based on its internal pre-set deterministic inference rules composed of comparison instructions and bit logic instructions. This rule performs trend analysis on the rate of change of operating parameters to identify early signs of faults, and executes corresponding levels of intervention actions based on the inference results, including: If the rate of increase of cooling water temperature is greater than the first rate threshold and the rate of increase of lubricating oil temperature is greater than the second rate threshold, it is determined that the radiator efficiency has decreased and a load reduction warning intervention is executed. If the rate of decrease in lubricating oil pressure is greater than the pressure drop rate threshold and the oil temperature is normal, it is determined that the lubricating oil filter is clogged, and a replacement prompt intervention is executed. If the detected fuel pressure fluctuation rate is greater than the fluctuation rate threshold and the exhaust temperature fluctuation is synchronized, it is determined that the fuel system is inlet and automatic exhaust intervention is executed.

[0063] Specifically, during the stable operation of the diesel generator, the PLC controller continuously collects operating parameters such as coolant temperature, lubricating oil temperature, lubricating oil pressure, fuel pressure, exhaust temperature, ambient temperature, and engine speed at a fixed sampling period of 1 second. A cyclic queue of 10 sampling points is maintained for each parameter, and the rate of change and volatility of parameters are calculated in real time based on adjacent sampled data. All fault identification logic is built upon the native comparison instructions and bit logic instructions of the Siemens CPU226CNPLC. A single rule, after compilation, has no more than 50 ladder diagram instructions, with an execution time of less than 0.5ms. All rules can be fully executed within a single 10ms scan cycle of the PLC, requiring no additional high-performance computing units and perfectly adapting to the operating performance of low-cost PLCs.

[0064] When the PLC detects a cooling water temperature rise rate exceeding a first threshold of 0.3℃ / s via a comparison instruction, and simultaneously determines through bitwise AND operation that the lubricating oil temperature rise rate exceeds a second threshold of 0.2℃ / s, and the ambient temperature is within the normal range of 15℃ to 35℃, it definitively identifies this as a precursor to a radiator efficiency decline fault and immediately executes a load reduction warning intervention. This intervention is a level two warning action. The PLC drives the horn to issue an audible and visual alarm via its output channel, and the corresponding fault indicator light flashes synchronously. Simultaneously, it sends a command to the speed controller to automatically reduce the engine load by 20%, or sends a load reduction request to the load distribution control unit to alleviate the radiator's heat exchange pressure and prevent further deterioration of the fault.

[0065] When the PLC detects a lubricating oil pressure drop rate exceeding the threshold of 0.5 PSI / s via a comparison instruction, and simultaneously determines through bitwise AND operations that the oil temperature is within the normal range of 80℃ to 95℃, and the engine speed fluctuation rate is less than 2%, it definitively identifies this as a precursor to a lubricating oil filter blockage and immediately initiates a replacement prompt intervention. The PLC records the fault trend information in registers and simultaneously issues a filter replacement prompt through the alarm output channel, driving the corresponding indicator light to flash, reminding maintenance personnel to perform maintenance work in advance and avoid lubricating oil supply interruptions caused by complete filter blockage.

[0066] When the PLC detects a fuel pressure fluctuation rate exceeding the 10% / s threshold via a comparison instruction, and simultaneously determines that the exhaust temperature is fluctuating synchronously and the engine speed fluctuation rate is greater than 5% through bitwise AND operations, it deterministically identifies this as a precursor to a fuel system intake fault and immediately executes automatic exhaust intervention. The PLC automatically controls the fuel supply system to perform the exhaust operation, increasing the fuel supply pressure to 1.2 times the normal value and maintaining it for 2 seconds to expel air from the fuel lines. Simultaneously, it triggers audible and visual warnings and records fault data.

[0067] The beneficial effects of this implementation are that, through multi-parameter joint deterministic reasoning rules, accurate identification of fault precursors and targeted proactive intervention are achieved on a low-cost PLC platform. Without the need for complex algorithm models, approximately 70% of potential major faults can be intervened in advance 30 seconds before they occur, reducing the unplanned engine downtime rate by 65%. While ensuring the safe operation of equipment, unnecessary shutdown actions are significantly reduced, improving the stability of diesel generator operation and maintenance efficiency.

[0068] As a specific implementation of this application, based on the basic scheme, the corresponding levels of intervention actions are further defined, including early warning intervention, protection intervention, and emergency intervention: Early warning level intervention is used to trigger audible and visual alarms and / or send load reduction commands to the governor to automatically reduce engine load; The protection-level intervention is used to first send a generator switch trip signal to unload all the load, and then perform a shutdown action after a delay; Emergency intervention is used to instantly trip the circuit breaker, disconnect the starter motor, and close the damper when an overspeed or knock signal is detected.

[0069] Specifically, the PLC controller, based on the fault diagnosis results output by deterministic reasoning rules and the fault trigger signals collected in real time during engine operation, matches and executes graded three-level intervention actions. The execution logic of all intervention actions is implemented based on the native bit logic instructions and timer instructions of the Siemens CPU226CN, ensuring precise and controllable execution timing. It is fully adapted to the typical 10ms scan cycle characteristic of the PLC and can achieve differentiated safety management based on the severity and development trend of the fault.

[0070] The early warning intervention is a level-two control action, primarily targeting early signs of faults that can be mitigated by load reduction. Upon triggering the early warning intervention, the PLC first drives the horn to issue an audible and visual alarm via the Q1.4 digital output channel, simultaneously illuminating the indicator light on the corresponding faulty channel, which flashes continuously at a 5Hz frequency. At the same time, the PLC sends a load reduction command to the 2301A electronic speed governor via the 4-20mA analog output channel, automatically reducing the engine operating load by 20%. It can also send a load reduction request to the AGLC load distribution control unit via the Q2.2 digital output channel, alleviating equipment operating load and suppressing further development of the fault trend without interrupting normal unit operation.

[0071] The protection-level intervention is a level 3 control action, which is used to execute a controlled shutdown procedure for serious faults that have been confirmed to be developing and cannot be mitigated by load reduction. After the PLC triggers the protection-level intervention, it first sends a 200ms pulse width trip signal to the generator 52G switch through the Q2.5 digital output channel to prioritize unloading all loads of the unit; then it starts an internal timer with a fixed delay of 0.5 seconds, waits for the load to be completely unloaded and the unit to enter a stable no-load state, and then executes the complete shutdown action, sequentially cutting off the starter motor control circuit, closing the fuel injection valve control output, and de-energizing the Q2.7 damper control channel to close the intake damper, ensuring that the unit shuts down smoothly under no-load conditions.

[0072] Emergency intervention is the highest priority safety control action, triggered when the PLC detects an overspeed signal, a knock signal, or a fire signal. This action has higher priority than all regular control tasks, skipping all timer delays upon triggering and instantly executing the entire safety action chain. The PLC simultaneously completes the generator switch tripping, starter motor control circuit disconnection, and damper control channel de-energization closure at the moment of triggering, while also latching the current fault state and prohibiting any restart attempts. Actual testing shows that the entire emergency intervention action takes no more than 10ms to execute, fully meeting the millisecond-level safety response requirements of diesel generators.

[0073] The beneficial effects of this implementation are that, through a tiered three-level intervention mechanism, a closed-loop safety management system for diesel generator faults is achieved, encompassing early warning, controlled shutdown, and emergency protection against extreme faults. Specifically, the unloading-then-shutting sequence of the protection-level intervention can reduce shaft impact caused by sudden stops under load by more than 80%, extending the unit's overhaul cycle by approximately 20%. The instantaneous response mechanism of the emergency-level intervention can completely avoid the risk of equipment damage caused by extreme faults such as overspeeding and knocking. The early warning-level intervention, while ensuring equipment safety, minimizes unnecessary shutdown actions, significantly improving the safety, stability, and service life of the diesel generator.

[0074] Figure 2 This is a schematic diagram of the structure of a PLC-based generator control device provided in an embodiment of this application, as shown below. Figure 2 As shown, it includes: control module 201, handover module 202, monitoring module 203, and analysis module 204.

[0075] The control module 201 is configured such that after receiving the start command, the PLC controller divides the start process into multiple stages based on the real-time speed obtained from the speed sensor, and executes different control strategies on the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage to assist the engine in reaching the ignition speed. The handover module 202 is configured to, after the real-time speed reaches the preset switching threshold range, the PLC controller performs pre-synchronization control on the speed governor, and when it is determined that the preset switching conditions are met, the engine control is handed over from the PLC controller to the speed governor. The monitoring module 203 is configured to continuously monitor the real-time speed of the PLC controller during a preset monitoring period after the switch is completed. If the speed fluctuation or speed drop exceeds the preset allowable range, the switch is determined to have failed and a rollback operation is immediately performed, and the PLC controller takes over the engine control again. The analysis module 204 is configured to collect multiple operating parameters, including cooling water temperature, lubricating oil pressure, and fuel pressure, in real time during the operation of the PLC controller. Based on its internally preset deterministic reasoning rules consisting of comparison instructions and bit logic instructions, it performs trend analysis on the rate of change of operating parameters to identify fault precursors and executes corresponding levels of intervention actions according to the reasoning results.

[0076] In some examples of this embodiment, the control module 201 is specifically configured such that when the real-time speed is lower than a first preset threshold, the PLC controller controls the starter motor to operate with a strong excitation voltage higher than the rated voltage for a first preset time period, and controls the fuel injection valve to inject fuel with a rich pulse width higher than the idle pulse width; when the real-time speed enters a second preset threshold before the preset resonance speed range, the PLC controller controls the supply voltage of the starter motor to decrease linearly to a first percentage of the rated voltage, and simultaneously controls the fuel injection valve to increase the injection pulse width linearly to a second multiple of the idle pulse width; after the real-time speed exceeds a third preset threshold, the PLC controller controls the supply voltage of the starter motor to decrease further to a second percentage of the rated voltage, and when a preset crankshaft angle before the top dead center of the compression stroke is detected, controls the fuel injection valve to output a short-duration fuel injection pulse.

[0077] In some examples of this embodiment, the control module 201 is specifically configured such that if the real-time speed does not reach the ignition success threshold within the preset total startup time, the PLC controller determines the cause of the startup failure based on the time consumption and speed change rate of each startup stage, and adjusts the amplitude and duration of the excitation voltage and the pulse width of the short-time fuel injection pulse in the next startup process according to the cause.

[0078] In some examples of this embodiment, the monitoring module 203 is specifically configured to reconnect the control circuit of the starter motor, restore the control output of the PLC controller to the fuel injection valve, and cut off the automatic control mode of the governor so that it returns to the standby mode.

[0079] In some examples of this embodiment, the analysis module 204 is specifically configured to determine that the radiator efficiency has decreased and to perform a load reduction warning intervention if the cooling water temperature rise rate is greater than a first rate threshold and the lubricating oil temperature rise rate is simultaneously greater than a second rate threshold; if the lubricating oil pressure drop rate is greater than the pressure drop rate threshold and the oil temperature is normal, it is determined that the lubricating oil filter is clogged and to perform a replacement reminder intervention; if the fuel pressure fluctuation rate is greater than the fluctuation rate threshold and the exhaust temperature fluctuation is synchronous, it is determined that the fuel system is intake air and to perform automatic exhaust intervention.

[0080] In some examples of this embodiment, the analysis module 204 is specifically configured to perform intervention actions at corresponding levels, including warning-level intervention, protection-level intervention, and emergency-level intervention: warning-level intervention is used to trigger an audible and visual alarm and / or send a load reduction command to the speed governor to automatically reduce the engine load; protection-level intervention is used to first send a generator switch trip signal to unload all loads, and then perform a shutdown action after a delay; emergency-level intervention is used to instantly perform tripping, disconnecting the starter motor, and closing the damper when an overspeed or knock signal is detected.

[0081] It should be noted that other corresponding descriptions of the functional units involved in the PLC-based generator control device provided in this embodiment can be found in [reference needed]. Figure 1 The corresponding descriptions in [the document] will not be repeated here.

[0082] Based on the above, Figure 1 The embodiment illustrates a PLC-based generator control method. Correspondingly, this embodiment also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-described method. Figure 1 This illustrates a PLC-based generator control method.

[0083] Based on the above, Figure 1 The embodiment illustrates a PLC-based generator control method. Correspondingly, this embodiment also provides a computer program product storing a computer program that, when executed by a processor, implements the above-described... Figure 1 This illustrates a PLC-based generator control method.

[0084] Based on this understanding, the technical solution of this application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as CD-ROM, USB flash drive, mobile hard drive, etc.) and includes several instructions to cause a computer device (such as personal computer, server, or network device, etc.) to execute the methods of various implementation scenarios of this application.

[0085] Based on the above, Figure 1 The diagram illustrates a PLC-based generator control method, and... Figure 2 To achieve the above objectives, the present application also provides an electronic device, such as a personal computer or a server, in the illustrated virtual device embodiment. This device includes a storage medium and a processor; the storage medium stores a computer program; the processor executes the computer program to implement the above-described virtual device. Figure 1 This illustrates a PLC-based generator control method.

[0086] In some embodiments, the aforementioned physical device may further include a user interface, a network interface, a camera, radio frequency (RF) circuitry, sensors, audio circuitry, a Wi-Fi module, etc. The user interface may include a display screen, an input unit such as a keyboard, etc., and optionally, a USB interface, a card reader interface, etc. In some embodiments, the network interface may include a standard wired interface, a wireless interface (such as a Wi-Fi interface), etc.

[0087] The storage medium may also include an operating system and a network communication module. The operating system is a program that manages the hardware and software resources of the aforementioned physical device, supporting the operation of information processing programs and other software and / or programs. The network communication module is used to enable communication between the various components within the storage medium, as well as communication with other hardware and software in the information processing physical device.

[0088] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0089] The above are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to these embodiments, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A PLC-based generator control method, characterized in that, include: After receiving the start command, the PLC controller divides the start process into multiple stages based on the real-time speed obtained from the speed sensor, and executes different control strategies on the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage to assist the engine in reaching the ignition speed. After the real-time speed reaches the preset switching threshold range, the PLC controller performs pre-synchronization control on the speed governor, and when it is determined that the preset switching conditions are met, the engine control is transferred from the PLC controller to the speed governor. During the preset monitoring period after the switch is completed, the PLC controller continuously monitors the real-time speed. If a speed fluctuation or speed drop is detected that exceeds the preset allowable range, the switch is determined to have failed, and a rollback operation is immediately performed, and the PLC controller takes over engine control again. During operation, the PLC controller collects multiple operating parameters in real time, including cooling water temperature, lubricating oil pressure, and fuel pressure. Based on its internally preset deterministic reasoning rules composed of comparison instructions and bit logic instructions, it performs trend analysis on the rate of change of the operating parameters to identify early signs of faults and executes corresponding levels of intervention actions according to the reasoning results.

2. The PLC-based generator control method according to claim 1, characterized in that, The starting process is divided into multiple stages based on the real-time rotational speed obtained from the speed sensor, and different control strategies are implemented for the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage, including: When the real-time speed is lower than the first preset threshold, the PLC controller controls the starter motor to operate with a strong excitation voltage higher than the rated voltage for a first preset time, and controls the fuel injection valve to inject fuel with a rich pulse width higher than the idle pulse width. When the real-time speed enters the second preset threshold before the preset resonance speed range, the PLC controller controls the power supply voltage of the starter motor to decrease linearly to the first percentage of the rated voltage, and simultaneously controls the fuel injection valve to increase the injection pulse width linearly to the second multiple of the idle pulse width. After the real-time rotational speed exceeds the third preset threshold, the PLC controller controls the power supply voltage of the starter motor to be further reduced to the second percentage of the rated voltage, and when the preset crankshaft angle before the top dead center of the compression stroke is detected, the PLC controller controls the fuel injection valve to output a short-duration fuel injection pulse.

3. The PLC-based generator control method according to claim 2, characterized in that, The method of dividing the starting process into multiple stages based on the real-time speed obtained from the speed sensor, and implementing different control strategies for the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage, further includes: If the real-time speed does not reach the ignition success threshold within the preset total startup time, the PLC controller determines the cause of the startup failure based on the time consumption and speed change rate of each startup stage, and adjusts the amplitude and duration of the excitation voltage and the pulse width of the short-time fuel injection pulse in the next startup process based on the cause.

4. The PLC-based generator control method according to claim 1, characterized in that, The immediate rollback operation, which restores engine control to the PLC controller, includes: Reconnect the control circuit of the starter motor, restore the control output of the PLC controller to the fuel injection valve, and disconnect the automatic control mode of the governor to return it to standby mode.

5. The PLC-based generator control method according to claim 1, characterized in that, The deterministic inference rules, based on its internally pre-defined rules consisting of comparison instructions and bit logic instructions, perform trend analysis on the rate of change of the operating parameters to identify early signs of faults, and execute corresponding levels of intervention actions based on the inference results, including: If the rate of increase of cooling water temperature is greater than the first rate threshold and the rate of increase of lubricating oil temperature is greater than the second rate threshold, it is determined that the radiator efficiency has decreased and a load reduction warning intervention is executed. If the rate of decrease in lubricating oil pressure is greater than the pressure drop rate threshold and the oil temperature is normal, it is determined that the lubricating oil filter is clogged, and a replacement prompt intervention is executed. If the detected fuel pressure fluctuation rate is greater than the fluctuation rate threshold and the exhaust temperature fluctuation is synchronized, it is determined that the fuel system is inlet and automatic exhaust intervention is executed.

6. The PLC-based generator control method according to claim 1, characterized in that, The corresponding levels of intervention include early warning intervention, protection intervention, and emergency intervention: Early warning level intervention is used to trigger audible and visual alarms and / or send a load reduction command to the speed governor to automatically reduce the engine load; The protection-level intervention is used to first send a generator switch trip signal to unload all the load, and then perform a shutdown action after a delay; Emergency intervention is used to instantly trip the circuit breaker, disconnect the starter motor, and close the damper when an overspeed or knock signal is detected.

7. A PLC-based generator control device, characterized in that, include: The control module is configured such that after receiving the start command, the PLC controller divides the start process into multiple stages based on the real-time speed obtained from the speed sensor, and executes different control strategies on the power supply voltage of the starter motor and / or the injection pulse width of the fuel injection valve in each stage to assist the engine in reaching the ignition speed. The handover module is configured such that after the real-time speed reaches a preset switching threshold range, the PLC controller performs pre-synchronization control on the speed governor, and when it is determined that the preset switching conditions are met, the engine control is handed over from the PLC controller to the speed governor. The monitoring module is configured to continuously monitor the real-time speed of the PLC controller during a preset monitoring period after the switch is completed. If the speed fluctuation or speed drop exceeds the preset allowable range, the switch is determined to have failed, and a rollback operation is immediately performed, and the PLC controller takes over the engine control again. The analysis module is configured to collect multiple operating parameters, including cooling water temperature, lubricating oil pressure, and fuel pressure, in real time during the operation of the PLC controller. Based on its internally preset deterministic reasoning rules composed of comparison instructions and bit logic instructions, it performs trend analysis on the rate of change of the operating parameters to identify early signs of faults and executes corresponding levels of intervention actions according to the reasoning results.

8. An electronic device, characterized in that, include: At least one processor; and a memory communicatively connected to the at least one processor; The memory stores instructions that can be executed by the at least one processor, which are executed by the at least one processor to enable the at least one processor to perform the PLC-based generator control method according to any one of claims 1-6.

9. A non-transitory computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to cause the computer to execute the PLC-based generator control method according to any one of claims 1-6.

10. A computer program product, characterized in that, It includes a computer program that, when executed by a processor, implements the PLC-based generator control method according to any one of claims 1-6.

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