36 results about "Smith predictor" patented technology

The invention discloses a high-robustness deadbeat predictive current control method which is suitable for current control of a dual three-phase permanent magnet motor driving system, and belongs to the technical field of permanent magnet motor control. The method mainly comprises the following steps: reconstructing a motor mathematical model by adopting a space vector decoupling matrix and Park transformation to obtain a motor voltage equation under a dqxy axis; designing a linear expansion state observer; a reference value of an output voltage vector is obtained in combination with deadbeat predictive current control; time delay in the digital control system is calculated, and angle delay is compensated; and designing a closed-loop Smith predictor for compensating a time delay link to complete high-robustness dead-beat predictive current control of the dual three-phase permanent magnet motor. The current loop design in the method does not depend on motor parameters, and the method has high parameter change robustness. By introducing the closed-loop Smith predictor, large delay of the system can be effectively compensated, and high-precision current tracking is realized under low switching frequency.

The invention discloses a precise temperature controller and a dynamic control method thereof.The precise temperature controller comprises a refrigerating unit, a precise temperature control unit and a multi-parameter decoupling controller, and a cooling water outlet of an evaporator in the refrigerating unit, the precise temperature control unit and a cooling water inlet of the evaporator are connected in a circulating mode; the precise temperature control unit comprises an auxiliary water tank, a main water tank, a constant-temperature water tank, an electromagnetic valve, an electric heater, a first temperature sensor, a second temperature sensor, a third temperature sensor, a fourth temperature sensor and a refrigerating unit. The electric heater of the precise temperature control unit, the control end of the electromagnetic valve, the first temperature sensor, the second temperature sensor, the third temperature sensor and the fourth temperature sensor are all connected with the parameter decoupling controller. The Smith predictor and the fuzzy PID are coupled for control, the rotating speed of the compressor and the opening degree of the electronic expansion valve are adjusted and corrected, condensation temperature dynamic optimization and water temperature fine adjustment control are combined, and the method has the advantages of being high in precision, quick in response and high in robustness.

The invention belongs to the technical field of internal combustion engine electronic control, and discloses a Smith-augmented reduced-order ESO common rail pressure control method based on online parameter identification, which comprises the following steps: step 1, data acquisition and preprocessing, step 2, high-pressure common rail system modeling and discretization to obtain a high-pressure common rail system discretization model, and step 3, high-pressure common rail system control. The method comprises the following steps of: 1, constructing an online parameter identification module based on a recursive least square method with a forgetting factor to solve a system pole parameter, a control gain parameter and a constant bias parameter, 3, calculating a time-delay-free virtual prediction rail pressure by a Smith predictor, 4, observing a total disturbance estimated value and a change rate estimated value of a system by an augmented reduced-order expansion state observer, and 5, calculating a total disturbance estimated value and a change rate estimated value of the system by the augmented reduced-order expansion state observer. And combining with the composite anti-interference control law, and controlling the output control quantity to act on a high-pressure oil pump actuator.

The invention relates to the technical field of automatic control of road construction equipment, in particular to a paving thickness control method and system for a paver, and the method comprises the steps: constructing a historical window, and constructing a mapping function of an average driving speed and a target lag parameter based on the historical window; constructing a current window, calculating a target lag parameter and a peak confidence coefficient of the current window, obtaining a current fitting lag value according to the mapping function, when the peak confidence coefficient is greater than a preset threshold value, updating the old residual error, and taking the sum of the fitting lag value and the updated residual error as an adaptive lag value; when the peak confidence coefficient is smaller than or equal to a preset threshold value, taking the sum of the fitting lag value and the old residual error as an adaptive lag value; and applying the adaptive lag value to a Smith predictor and a PID controller, and outputting a control quantity. According to the invention, self-adaptive adjustment can be realized, so that a control system can more accurately compensate control delay caused by lagging, and the control precision of the thickness of the laying layer is improved.

The application belongs to the technical field of magnetic shielding and active magnetic field compensation, and discloses a magnetic field interference suppression system and method based on full-parameter adaptive time delay compensation, which comprises the following steps: collecting the output signal of a magnetic field sensor by using an ADC module, wherein the signal has a time delay due to the characteristics of the sensor; calculating and updating the parameters of a Smith predictor reference model and a time delay by using a full-parameter adaptive module, performing time delay compensation on the signal containing the time delay by using a Smith predictor; and calculating a control amount by using a controller, and applying a current to a magnetic compensation coil after passing through a DAC module and a high-precision current source, so as to realize the suppression of magnetic field interference. The technical scheme of the application can adaptively update the reference model and the time delay of the Smith predictor, improve the time delay compensation accuracy and the system stability, thereby reducing the influence of the modeling error of the controlled object on the magnetic field interference suppression performance, and being suitable for the magnetic field stability control inside a magnetic shielding device.

This invention discloses a time-delay-resistant and energy-saving motion control method and system for a flat-type all-wheel-drive AUV. The invention includes: constructing a six-degree-of-freedom hydrodynamic model of the AUV based on submarine maneuverability theory; identifying the setpoint pure time delay and rotational acceleration characteristics of the propeller through multi-condition testing, and constructing a nonlinear propeller dynamic model including a pure time delay element and a nonlinear rotational speed dynamic response model; constructing a composite control architecture integrating a dual-loop PID controller, a Smith predictor, and a model reference adaptive controller (MRAC); using the Smith predictor to perform explicit time delay compensation for the vertical plane motion subsystem, and using MRAC to update the adaptive gain online to compensate for model mismatch. This invention effectively suppresses high-frequency pitch angle jitter, reduces ineffective commutation movements and energy consumption of the propeller, and significantly improves the high-speed operational stability and endurance of the flat-type AUV.

The invention discloses a self-tuning delay method and system for suspension load vibration control, and relates to the field of mechanical structure vibration control. According to the method, a parameter observation function is introduced into a self-tuning delay control algorithm, so that the delay parameter can be adaptively adjusted in real time according to the changing rope length, and the control algorithm can still keep robust and effective vibration suppression performance under the condition that the system parameter (such as the rope length) is continuously changed; the problem of performance degradation of a traditional control method in a time-varying system is solved; in the core time lag parameter design of the self-tuning time lag control algorithm, the inherent closed-loop time lag of the system is directly integrated, and the use of a traditional time lag compensator (such as a Smith predictor and model predictive control) which is complicated and depends on a high-precision model is avoided, so that a control loop is basically not influenced by the system feedback time lag, and the control precision is improved. And an effective and simple solution is provided.

The present application relates to the technical field of irradiance measurement, and more particularly to a radiation meter absorption cavity temperature bistable control method based on adaptive Smith predictor, which combines feedforward control, PI control and adaptive Smith predictor: feedforward control is performed on the absorption cavity temperature interference source in the measurement process, an adaptive Smith predictor is used to predict the behavior of the radiation meter absorption cavity, PI control is used to complete the electric heating output of the radiation meter absorption cavity, the output of the temperature controller and the controlled cavity temperature are quickly adjusted, and the stable state is simultaneously entered, and high-precision radiation meter absorption cavity temperature and stable electric heating output meeting the measurement accuracy requirement are obtained.

The invention relates to the technical field of horizontal continuous casting temperature control, in particular to a continuous casting control method for isothermal quenching ductile iron production, which comprises the following steps: acquiring the temperature of each preset position in a heating furnace in real time, and acquiring the heating power of the heating furnace and the temperature of a casting in real time; for the Smith predictor used for temperature control in the heat preservation stage in the austenitizing process and the isothermal quenching process, the time constant of a reference model in the Smith predictor is adjusted, and the temperature is controlled based on the adjusted Smith predictor; the process of adjusting the time constant comprises the following steps of: obtaining a temperature distribution factor, thermal response lag time and a power influence factor at each acquisition moment; and further obtaining a heat transfer compensation coefficient at each acquisition moment, and adjusting a time constant of a reference model in the Smith predictor. The invention aims to improve the accuracy of temperature control and avoid temperature fluctuation in the heat preservation stage.

The application discloses a heavy haul train control method and system based on vehicle dynamic response identification, and relates to the technical field of train control.The method comprises the following steps: dividing the carriages of the heavy haul train into multiple blocks according to the differences in the dynamic responses of different carriages of the heavy haul train; taking the tractive force or braking force of each block as input and the train speed as output to establish a vehicle operation model for each block; using a Smith predictor to compensate for the time delay characteristics of the speed of the heavy haul train under complex line conditions; when the speed variation of the heavy haul train or the acceleration variation under stepless speed regulation exceeds the set range, using a fuzzy PID-Smith time delay controller to control the output speed of the vehicle operation model; and when the speed tracking accuracy of the heavy haul train exceeds the set range, using an improved particle swarm algorithm to dynamically adjust the parameters of the fuzzy PID-Smith time delay controller.The application improves the parameter setting accuracy and the reliability of the control under the time delay characteristics of the heavy haul train.

This invention discloses a testing device for sensitive components of a linear temperature-sensitive fire detector, belonging to the field of fire detector testing technology. It includes a housing, a heating system, a temperature control system, and a heat dissipation system. The heating system employs a surface-mount heat conduction heating cavity and a matching heating device. The temperature control system is based on a PLC industrial control integrated computer. This invention designs standardized testing methods for both constant-temperature and differential-temperature alarm-type sensitive components. During the heating process, online thermal characteristic identification and predictive temperature control algorithms achieve precise regulation of the temperature rise rate. During the constant-temperature process, a Smith predictor combined with an adaptive PI algorithm achieves stable temperature control. Multiple safety protection functions are also included. This invention solves the problems of low temperature control accuracy, non-standardized testing procedures, inability to realistically simulate the temperature rise process, low testing efficiency, and potential safety hazards in existing testing methods. The testing process closely matches the actual working environment of the component, and the results meet standard testing requirements.

The invention relates to the technical field of fixed-wing unmanned aerial vehicle control, in particular to a fixed-wing unmanned aerial vehicle control surface control method with gust response and hysteresis characteristics. Comprising the following steps: compensating time lag by an inner ring Smith predictor, realizing anti-interference control by an outer ring ADRC controller, and completing integrated operation of the Smith predictor and the ADRC controller; performing joint optimization on the parameters of the Smith predictor and the ADRC controller; and completing control surface control of the unmanned aerial vehicle according to an integrated operation result of the Smith predictor and the ADRC controller. According to the method, the steering engine time lag influence is effectively compensated through the Smith predictor, the anti-interference capability of the system to gust disturbance is enhanced in combination with the ADRC technology, the combination of time lag compensation and the anti-interference capability is completed, and the method is suitable for steering engine control of the unmanned aerial vehicle with the high aspect ratio in the high-dynamic and high-uncertainty environment.

This invention discloses an adaptive control method for an engine exhaust nozzle actuator. The invention improves upon the traditional Smith predictor and combines it with a second-order linear LADRC controller to control the engine exhaust nozzle actuator. The improved Smith predictor includes a traditional Smith predictor and a first-order filter. The output y1 of the system's built-in model of the traditional Smith predictor after a time delay is compared with the output y1 of the controlled object. p The difference dy between the two values ​​is filtered by the first-order filter to compensate for model inaccuracies. The output y of the traditional Smith predictor's built-in model does not go through a time delay element. p The sum of the output signal of the first-order filter and the output signal of the first-order filter is used as the tuned system output y′ of the improved Smith predictor. This invention also discloses an adaptive control device for an engine exhaust nozzle actuator. This invention can maintain high control accuracy even when the exhaust nozzle actuator experiences various degradations such as gain degradation and delay degradation.

A control method for vehicle magnetorheological suspension based on dual-timescale separation includes: establishing an equivalent drive circuit model with time delay; separating the equivalent drive circuit model into two timescales based on singular perturbation theory to construct a fast-changing current subsystem and a slow-changing control subsystem; designing a slow-changing control subsystem controller for the slow-changing control subsystem, calculating the reference current output by the slow-changing control subsystem, and then outputting the reference current to the fast-changing current subsystem; designing a fast-changing current subsystem controller for the fast-changing current subsystem, designing a Smith predictor to compensate for the time delay, and calculating the compensated duty cycle output by the fast-changing current subsystem by combining the reference current and the non-singular reaching law; and outputting the compensated duty cycle to the equivalent drive circuit model to achieve real-time control of the magnetorheological suspension. This invention can effectively handle the multi-source time delay problem of magnetorheological suspension in two timescales, improving vehicle ride comfort and handling stability.

The invention discloses a pre-estimation-self-adaption-fuzzy coupling type constant-temperature air conditioner control method, and belongs to the technical field of air conditioning. According to the technical scheme, the system comprises an evaporator, a reheater and a fan which are located in an air duct of the air conditioner, an outlet of a compressor is connected with the reheater and a condenser, the reheater and the condenser are connected with the evaporator through an electronic expansion valve and a thermostatic expansion valve, the evaporator is connected with the compressor, the electronic expansion valve is electrically connected with a temperature control module, and the temperature control module is electrically connected with the fan. The temperature control module is electrically connected with an air outlet temperature sensor in an air conditioner air duct. The method has the beneficial effects that a dual compensation mechanism is constructed by introducing the Smith predictor and the tanh self-adaptive compensator, the problem that the control quality of the constant-temperature air conditioning system is reduced due to delay characteristics and model mismatch is effectively solved, and the control precision and robustness of the system under set value change and external disturbance are improved through cooperative work of the Smith predictor and the tanh self-adaptive compensator.

The application discloses a kind of self-regulating reaction kettle temperature control methods based on fuzzy Smith-PID, belong to temperature control technical field, its steps are: first, the first-order inertia model of reaction kettle temperature system is obtained, then the temperature error and error change quantity are fuzzed, fuzzy rule is formulated, then the real-time PID parameter value is obtained by fuzzy rule table, self-regulating control is realized, finally, the Smith predictor model of reaction kettle is obtained by offline test method, and is brought into system to obtain the self-regulating reaction kettle temperature control method based on fuzzy Smith-PID.The method of the application is aimed at the large lag, nonlinearity, strong interference of reaction kettle temperature control system, the self-regulating of controller is realized by the method of fuzzy Smith-PID, and the stability and response speed of system are improved, and the application field of reaction kettle system is widened.

The present application relates to the technical field of automatic control of road construction equipment, and particularly relates to a paving thickness control method and system for a paver, the method comprising: constructing a history window, constructing a mapping function of average driving speed and target lag parameter based on the history window; constructing a current window, calculating a target lag parameter and a peak confidence of the current window, obtaining a current fitting lag value according to the mapping function, when the peak confidence is greater than a preset threshold, updating an old residual error, taking a sum of the fitting lag value and the updated residual error as an adaptive lag value; when the peak confidence is less than or equal to the preset threshold, taking a sum of the fitting lag value and the old residual error as the adaptive lag value; applying the adaptive lag value to a Smith predictor and a PID controller, and outputting a control quantity. The present application can adaptively adjust, so that the control system can more accurately compensate for the control delay caused by lag, and improve the control precision of the paving thickness.

The invention relates to the technical field of irradiance measurement, in particular to a radiometer absorption cavity temperature bistable control method based on self-adaptive Smith estimation, which combines feed-forward control, PI control and a self-adaptive Smith predictor. A self-adaptive Smith predictor is adopted to predict behaviors of a radiometer absorption cavity, electric heating output of the radiometer absorption cavity is completed through PI control, output of a temperature controller and the temperature of a controlled cavity are rapidly adjusted, the radiometer absorption cavity enters a steady state synchronously, and meanwhile the cavity temperature of the high-precision radiometer absorption cavity and stable electric heating output meeting the measurement precision requirement are obtained.

The invention provides a water feeding control method suitable for a grab ship unloader under a low-temperature condition, and belongs to the technical field of water feeding of grab ship unloaders. Real-time position signals of the grab ship unloader are collected and preprocessed; based on the preprocessed signal and the real-time speed of the grab ship unloader, the movement track of the grab ship unloader in the future preset time is predicted; determining driving input of a driving module of the grab ship unloader by taking the minimum distance between the predicted trajectory and the actual trajectory as a target; based on the driving input, the grab ship unloader is controlled to be in butt joint with a ground water supply point; after finishing connection, determining the opening degree of each water feeding valve through fuzzy control, and carrying out water feeding on the grab ship unloader; the Smith predictor outputs compensation temperature based on the water storage equipment heat loss mathematical model; and the heating power of the heat tracing device of each water storage device is determined through the fuzzy controller according to the deviation between the preset temperature and the compensation temperature of each water storage device, so that each water storage device is stabilized in a set range. The grab ship unloader can be in automatic butt joint with a ground water supply point and self-adaptive water feeding is achieved.

The application provides a kind of heat-assisted pair wheel spinning temperature control method based on deep reinforcement learning, belongs to the technical field of temperature control, the present application reconstructs the full-field temperature distribution of blank by fusing infrared array sparse measuring point and heat conduction equation residual through physical information neural network;With the realization of thermal response lag compensation by combining the principle of Smith predictor with the condition variation cycle strategy model of thermal-mechanical dual modal fusion;With the joint training of multi-flame gun strategy network in the framework of centralized training and decentralized execution, the coupled thermal field of multiple guns is optimized collaboratively;With Lyapunov guide safety exploration algorithm to perform gradient projection on each power regulation action, ensure that the system state is continuously in the thermodynamic safety domain;With the isomorphism migration strategy alignment algorithm to match similar working conditions from the historical working condition library and generate target working condition strategy initialization parameters;Solved the technical problem that the coupled thermal field of multiple flame guns is difficult to achieve precise closed-loop temperature control in the process of heat-assisted pair wheel spinning under dynamic spinning conditions.

This application relates to an intelligent environmental collaborative control method and system for plant cultivation in confined spaces. The method includes: collecting multidimensional environmental and plant phenotypic data to generate an input state vector containing the errors and rates of change of each parameter; inputting the input state vector in parallel into a fuzzy controller with a built-in coupled rule base, and outputting a preliminary decision vector through inference; using an improved particle swarm optimization algorithm with time multiplication by the integral of absolute error as the objective to optimize the quantization factor and scaling factor of the fuzzy controller, generating a control decision vector; addressing system feedback delay by connecting Smith predictors in parallel to each loop, utilizing delay-free predictive output to participate in feedback regulation in advance, eliminating lag effects, and obtaining a compensated final control command vector; monitoring photovoltaic power generation and battery status, running a variable-step MPPT algorithm to calculate available power, and if power supply is insufficient, initiating an energy consumption optimization strategy to adjust the load or regenerating and executing commands.

The application relates to a control system and an optimization control method based on a composite controller and relates to the field of advanced control technology. The existing nonlinear time-delay system is generally present in complex industrial control and automation systems, and traditional control strategies are difficult to effectively cope with the problems caused by time delay and nonlinearity. The application eliminates the influence of time delay in the system by designing a Smith predictor, and introduces a fractional order controller to enhance the adaptability of the system to nonlinear behavior. The composite controller formed by combining the Smith predictor and the fractional order controller can significantly improve the dynamic response performance and control accuracy of the system. In order to further optimize the controller parameters, an improved artificial rabbit optimization algorithm is adopted. The algorithm improves the global search ability and convergence speed by introducing a dynamic adjustment factor, a Levy flight strategy and a boundary control strategy.

The application belongs to the field of automation control technology, and particularly relates to a PID control system based on Smith predictor and a parameter setting method, the setting direction of the system parameter method is clear, the setting method is visual and intuitive, has clear debugging rules and physical meaning, can better meet the debugging habits of field control engineers, and avoids the problems of unclear parameter meaning and unclear debugging process caused by experience setting formula; the application is widely applicable to the field of industrial process automation control, and is particularly applicable to the fields of process control of thermal power plants, petroleum chemical industry, steel metallurgy and the like.

The application discloses a kind of based on urban road's intelligent cleaning path planning method of sanitation vehicle, and the road edge and obstacle profile in the working environment of sanitation vehicle are identified by laser radar sensor and binocular camera sensor, and the positioning deviation is corrected using extended Kalman filter fusion IMU data, obtain high-precision map and dynamic traffic data, and energy consumption hot spot area is marked in road topology diagram;Using LPV-MPC control model, the load change and brake delay of vehicle when working in the first working path of sanitation vehicle are compensated by fusing Smith predictor, the yaw angle is adjusted based on adaptive PID algorithm, and the path tracking error model is fed back to MPC controller;If it can be passed, output uniform speed travel instruction, otherwise generate steering instruction.The accurate control of vehicle driving direction and speed is realized.The sanitation vehicle can stably travel under various working conditions, accurately track the planned path, and improve the quality and effect of cleaning operation.

The application discloses a kind of crystallizer liquid level control methods based on improved Smith prediction compensation, by setting Smith prediction compensation link in liquid level control system, the pre-estimation and compensation to control process dynamic response are established, so that the leading reaction of the time delay time in system is advanced to liquid level regulator, the advance action of liquid level regulator is realized, including steps:1: according to the signal of the liquid level control system of the time delay time of bar impact is determined;2: with the form of decoupling of set response and disturbance response, the structure setting of Smith predictor is completed, the Smith predictor structure with double controller of tracking controller and disturbance controller is formed3: respectively complete the determination of each parameter in tracking controller and disturbance controller, and according to the determination, the Smith-based prediction compensation is completed.The application can realize the determination of time delay time and the elimination control of system steady-state error.

The invention provides a precise environment temperature control method, which belongs to the technical field of precise environment temperature control, and comprises the following steps of: arranging a temperature sensing dot matrix by adopting a high-symmetry bridge temperature measurement circuit to acquire temperature data to construct a three-dimensional temperature field snapshot matrix; inputting the three-dimensional temperature field snapshot matrix into a temperature field reduced order prediction model constructed by a dynamic convolution-based adaptive filter generation algorithm, outputting a dominant spatial modal coefficient and a time coefficient reconstruction sequence, and calculating a temperature uniformity deviation index according to the time coefficient reconstruction sequence to control a spiral airflow guide structure; a cascade control architecture is combined with a current pre-compensation algorithm and a Smith predictor to perform temperature adjustment, transfer function parameters are identified on line through a recursive least square algorithm to dynamically adjust an advanced correction coefficient, and the problem that a precise temperature control system cannot realize rapid and accurate prediction and response of a temperature field when facing external thermal disturbance is solved.

The invention discloses a deep learning-based remote control system for mechanical equipment in a closed space, and the system comprises a data collection module which collects and completes the alignment of an image, an environment distance and motion state data; the data fusion module is used for extracting space-time fusion features through image enhancement and an image convolutional network; the cooperative compensation module is used for realizing delay compensation and prediction state output by utilizing a Smith predictor and a multi-layer long and short time memory network coupling residual structure; the hybrid control network module is used for generating control parameters through adaptive fusion based on model prediction control and H-infinity robust control; the instruction issuing and feedback module is responsible for driving instruction issuing and feedback acquisition; and the on-line self-adaptive updating module is used for carrying out on-line fine adjustment on the compensation network based on the feedback error. According to the invention, the precision, the real-time performance and the robustness of remote control in the closed space are improved.

The invention discloses a commercial vehicle double-motor electric drive axle synchronous control method considering a time lag influence, and the method comprises the steps: improving the speed tracking robustness and synchronization precision of double motors of an electric drive axle under the influence of time lag and external disturbance through designing an explicit model prediction controller; meanwhile, a cross coupling control structure is adopted to generate a compensation signal for synchronous control of the two motors, the compensation signal is fused into a combined control framework composed of an explicit model prediction controller and an enhanced Smith predictor, the stability of the dual-motor system is enhanced, meanwhile, the online calculation complexity is remarkably reduced, and the system performance is improved. And the synchronous control capability of the commercial vehicle double-motor electric drive axle influenced by the time lag is improved.

The application discloses a full-link temperature control method and system for breath alcohol detector testing, and belongs to the technical field of temperature control, comprising: acquiring the temperature of each temperature zone and the gas flow; constructing a series lag model and calculating feedforward compensation by using a Smith predictor; dividing three modes of full-speed temperature rise, approaching constraint and steady-state fine adjustment based on deviation, enabling anti-integral saturation PID control in the steady state; correcting the gas set value based on sensor thermal balance backstepping; adopting segmented Hermite interpolation for nonlinear compensation, and updating the compensation parameters online by using a variable forgetting factor RLS algorithm. The application effectively improves the testing temperature control precision, response speed and environmental adaptability, and ensures the accuracy and reliability of the testing results.

The invention provides a temperature control method, device and system. The method is used for controlling steel to be cooled to a target temperature within a preset time after intermediate rolling treatment. The method comprises the following steps: receiving a first temperature signal and a second temperature signal; predicting a first predicted temperature corresponding to a finish rolling starting section based on the first temperature signal and predicting a second predicted temperature corresponding to a finish rolling discharging section based on the second temperature signal by using a gray prediction controller; judging whether a temperature difference value between the second predicted temperature and the target temperature is greater than a temperature threshold value or not; and if the temperature difference value is greater than the temperature threshold value, determining a first cooling parameter and a second cooling parameter by using a Smith predictor based on the first predicted temperature, the second predicted temperature and the target temperature. In this way, the steel can be accurately controlled to be cooled to the target temperature within the preset time, and the prepared steel meets the grain refinement requirement.