Method, system and computer device for controlling elevator brake using genetic PID

Abstract

This article relates to a method, system and computer device for controlling elevator brakes using genetic PID. The method includes: providing a PID controller with a real-time measured current value in the brake coil of each brake caliper; using the PID controller to generate a control signal for adjusting the current supply of the brake coil of the corresponding brake caliper according to the measured current value and a preset target current value; obtaining the actual required braking force of each brake caliper during the braking process; optimizing the PID parameters of the PID controller using a genetic algorithm according to the actual required braking force of each brake caliper; and adjusting the control signal using the optimized PID parameters through the PID controller. The real-time current of the brake coil is adjusted to adjust the pull-in force of the brake caliper, and the pull-in force is intelligently adjusted by controlling the pull-in force to avoid the problem of brake overload or failure, so as to achieve the best braking effect, ensure the safe operation of the elevator, and improve the real-time performance and reliability of the entire elevator control system.

Description

Technical Field

[0001] The present invention relates to the field of elevators, and more particularly, to a method, system and computer device for controlling elevator brakes using genetic PID. Background Art

[0002] The elevator electromagnetic brake is a key component for the safe operation of the elevator, and the control method of its braking current is crucial. The working principle of the elevator electromagnetic brake is based on the electromagnetic effect. When the brake is powered on, the electromagnet generates suction, which overcomes the spring pressure to make the brake shoe separate from the traction wheel or brake wheel, thus releasing the brake and allowing the elevator to operate. When the power is cut off, the electromagnet loses suction, and the brake shoe holds the traction wheel or brake wheel tightly under the spring pressure to achieve braking.

[0003] However, the existing brake control method cannot adjust the brake current of the brake according to the operating state of the elevator brake and as needed, thereby failing to achieve real-time control of the brake. Summary of the invention

[0004] The embodiment of the present invention provides an intelligent control method for controlling the braking force of an elevator brake by using a genetic PID (Proportional Integral Derivative) method, which adjusts the braking current of the brake according to the operating state of the elevator brake and as required to achieve real-time control of the brake.

[0005] In one aspect, an embodiment of the present invention relates to a method for controlling an elevator brake using a genetic PID, wherein the elevator brake comprises at least two brake calipers, for example, the elevator brake is a multi-caliper disc elevator brake, the method comprising:

[0006] Providing the PID controller with the current value in the brake coil of each brake caliper measured in real time;

[0007] generating, using the PID controller, a control signal for adjusting the current supply to the brake coil of the corresponding brake caliper according to the measured current value and a preset target current value;

[0008] Obtain the actual required braking force of each brake caliper during braking;

[0009] For each brake caliper, according to the actual required braking force of the corresponding brake caliper, a PID parameter of the PID controller is optimized using a genetic algorithm;

[0010] The control signal is adjusted by the PID controller using optimized PID parameters.

[0011] In some embodiments of the present invention, the current value in the brake coil is measured in real time by a current sensor, and the current value is provided to the PID controller at a frequency of milliseconds.

[0012] In some embodiments of the present invention, the generation of the control signal includes:

[0013] Calculate the error between the measured current and the target current;

[0014] According to the current error, the control signal is generated using formula (1):

[0015] (1)

[0016] in, represents the control signal, are the gain coefficients of the proportional, integral and differential links of the PID controller, Indicates the error between the current and the target current.

[0017] In some embodiments of the present invention, obtaining the actual required braking force of each brake caliper during the braking process includes:

[0018] Obtaining observation parameters of each brake caliper, wherein the observation parameters include brake response time, brake disc temperature, wear and braking distance;

[0019] According to the obtained observation parameters, the actual required braking force of each brake caliper is obtained.

[0020] In some embodiments of the present invention, for any j-th brake caliper ( An integer, n represents the number of brake calipers), the optimization of the PID parameters of the PID controller includes the following processing:

[0021] S1: Set the parameters of the genetic algorithm, including population size, crossover probability, mutation probability and maximum number of iterations, and initialize the parameter ranges of the PID controller;

[0022] S2: Randomly generate a set of PID parameters as the initial population;

[0023] S3: For each individual in the population, its PID parameters are applied to the PID controller and the response of the brake is simulated to obtain the current value corresponding to the corresponding brake caliper;

[0024] S4: calculating the fitness value of each individual according to the actual required braking force of the brake caliper and the current value corresponding to the brake caliper;

[0025] S5: Determine whether the termination condition is met. If so, proceed to process S6; otherwise, proceed to process S7;

[0026] S6: Stop iteration and output optimized PID parameters;

[0027] S7: Selecting a portion of individuals as parents of the next generation according to the fitness value;

[0028] S8: Perform a crossover operation on the selected parent generation to generate new offspring individuals;

[0029] S9: Perform mutation operation on the newly generated offspring individuals;

[0030] S10: Combine the offspring individuals generated after the crossover and mutation operations into a new population, replace the original population, and return to process S3.

[0031] In some embodiments of the present invention, in process S3, the individual variable is represented as: ,in, represents the i-th individual variable, i is an integer greater than 1 and less than or equal to the number of populations, a ij is the weight coefficient of the jth brake caliper, wherein, initially, the weight coefficients of the n brake calipers are equal and sum to 1; applying the individual variables to the PID controller, according to formula (1), K p , K i and K d The change in value affects The change of will affect the current change of the corresponding brake coil, so the corresponding braking force is expressed as:

[0032] , is the input control force of the jth brake caliper, I ij is the current size corresponding to the brake caliper.

[0033] In some embodiments of the present invention, in process S4, the objective function is applied , and through the fitness function To calculate the fitness value ;

[0034] Among them, the objective function is:

[0035]

[0036] Constraints:

[0037]

[0038] is the actual braking force required by the j-th brake caliper, and F is the total force required for braking.

[0039] In some embodiments of the present invention, in process S5, when a predetermined number of iterations is reached or the fitness value of the current optimal individual is the smallest, it is determined that the termination condition is met.

[0040] In another aspect, an embodiment of the present invention relates to a system for controlling an elevator brake using a genetic PID, comprising:

[0041] A power supply module, which provides working current for the brake;

[0042] A brake coil configured to generate an electromagnetic force when current flows therethrough to control each brake caliper of the brake;

[0043] a current control module configured to generate a control signal for controlling the current supply of the brake coil using a genetic PID controller, and receive a feedback current signal of the brake coil;

[0044] a current regulating module, configured to receive a control signal from the current control module to regulate the current output by the power module, and output the regulated current to the brake coil;

[0045] The host computer is configured to execute the method described in any embodiment of the present invention to obtain optimized PID parameters, and provide the parameters to the current control module.

[0046] In addition, an embodiment of the present invention relates to a computer device, comprising:

[0047] a memory storing computer-readable instructions and data;

[0048] A processor, which performs at least a portion of the operations of the method described in any embodiment of the present invention according to the computer-readable instructions and data to obtain optimized PID parameters;

[0049] A communication module is configured to send the optimized PID parameters to a current control module.

[0050] The embodiments of the present invention can collect the operating status parameters of the brake caliper in real time, such as the braking response time, the temperature of the brake disc, the degree of wear and the braking distance, adjust the real-time current of the brake coil of a single brake caliper, and then control the suction force of the brake caliper. By controlling the suction force, the braking force can be intelligently adjusted to avoid the problem of brake overload or failure, so as to achieve the best braking effect, ensure the safe operation of the elevator, and improve the real-time performance and reliability of the entire elevator control system.

[0051] Various aspects, features, advantages, etc. of the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 Detailed Description of the Invention It is a block diagram showing a system for controlling any brake caliper of a multi-caliper disc elevator brake using a genetic PID according to an embodiment of the present invention.

[0053] Figure 2 : is a block diagram showing an example of a system for controlling any brake caliper of a multi-caliper disc elevator brake using a genetic PID according to an embodiment of the present invention.

[0054] Figure 3 Detailed Description of the Invention is a block diagram showing an example of a computer device that can be used to control any brake caliper of a multi-caliper disc elevator brake according to an embodiment of the present invention.

[0055] Figure 4 Detailed description is a flow chart showing an example process for optimizing PID parameters of an arbitrary brake caliper of a multi-caliper disc elevator brake according to an embodiment of the present invention.

[0056] In the figure: 100-power module, 200-brake coil, 300-current control module, 400-current regulation module, 500-indicator light, 600-brake electromagnetic attraction device, 700-host computer, 301-control core, 302-EEPROM, 303-Flash (flash memory), 304-communication module, 305-power input module, 401-pulse width adjustment module, 402-comparator, 701-processor, 702-memory, 704-display, 705-speaker, 706-communication module, 707-I / O module, 801-acquisition module, 802-current acquisition chip. DETAILED DESCRIPTION

[0057] Herein, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. It should be understood that the present invention can be embodied in a variety of different forms and should not be construed as being limited to the embodiments described herein. Instead, these embodiments are provided as examples so that the disclosure herein will be thorough and comprehensive, and fully convey the various aspects and features of the present invention to those skilled in the art. In the description, operations, processes, elements, units, etc. that are not necessary for those of ordinary skill in the art to fully understand the various aspects and features of the present invention may not be described.

[0058] In this article, unless the context clearly indicates, the terms "first", "second" and other similar words are only used to distinguish different objects and do not mean order or sequence. It should also be understood that the words "comprise", "include" and "have" etc. specify the existence of stated features, processes, steps, operations, elements and / or parts when used in this article, but do not exclude the existence or addition of one or more other features, processes, steps, operations, elements, parts and / or their collections. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Expressions such as "at least one of..." modify the entire list of elements when they are before the list of elements, rather than modifying the individual elements of the list.

[0059]

[0013] In this document, the terms "substantially," "about," and similar terms are used as terms of approximation rather than terms of degree, and are intended to take into account errors or variations in measurements or calculations that would be recognized by one of ordinary skill in the art.

[0060] Furthermore, unless otherwise defined, all terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

[0061] This article discloses an intelligent control scheme for the braking force of an elevator electromagnetic brake. By real-time acquisition of the operating status parameters of the brake caliper, the real-time current of a single electromagnetic brake is adjusted to control the pull-in force. By controlling the pull-in force, the braking force is intelligently adjusted to avoid brake overload or failure problems, thereby achieving the best braking effect, ensuring the safe operation of the elevator, and improving the real-time performance and reliability of the entire elevator control system.

[0062] like Figure 1 As shown, a system for controlling a multi-caliper disc elevator brake using genetic PID is illustrated in accordance with the present invention. The system can be used for any brake caliper of a multi-caliper disc elevator brake and comprises at least a power supply module 100, a brake coil 200, a current control module 300, a current regulation module 400 and a host computer 700.

[0063] The power module 100 provides the working current of the brake. In some embodiments, the power module 100 can convert an AC voltage (eg, 220V) into a stable DC voltage through a rectifier bridge, thereby providing the working current to the brake coil 200 .

[0064] The brake coil 200 is configured to generate electromagnetic force when current passes through it to control the corresponding brake caliper of the brake. When the brake coil 200 receives current, it generates sufficient magnetic force to make the brake electromagnetic attraction device 600 achieve attraction (brake holding) action; when the coil loses current, the magnetic force disappears, and the brake electromagnetic attraction device 600 achieves release (release) action.

[0065] The current control module 300 is configured to use a genetic PID controller to generate a control signal for controlling the current supply of the brake coil 200, and receive the feedback current (or voltage) signal of the brake coil. In some embodiments, the current control module 300 adjusts the braking current of the brake according to the operating state of the elevator brake. For example, the feedback signal is processed in combination with a preset control algorithm and logic, and a control signal is output to the current regulation module 400. The current regulation module 400 adjusts the current of the brake coil according to the control signal. At the same time, the feedback circuit feeds the current signal of the brake back to the current control module 300 to achieve closed-loop control. In some embodiments, after the system of the present invention collects the operating state parameter data of the elevator brake through the sensor, it uses an advanced genetic PID algorithm to analyze and process the data, and outputs an accurate control signal to the current regulation module 400 accordingly.

[0066] The current regulating module 400 is configured to receive a control signal from the current control module 300 to regulate the current output by the power module and output the regulated current to the brake coil 400 .

[0067] The host computer 700 is configured to execute the method described in any embodiment of the present invention to obtain optimized PID parameters, and provide the parameters to the current control module 300. The method includes providing the current value in the brake coil of each brake caliper measured in real time to the PID controller; using the PID controller to generate a control signal for adjusting the current supply of the brake coil of the corresponding brake caliper according to the measured current value and a preset target current value; obtaining the actual required braking force of each brake caliper during the braking process; for each brake caliper, according to the actual required braking force of the corresponding brake caliper, using a genetic algorithm to optimize the PID parameters of the PID controller.

[0068] In some embodiments, the host computer 700 includes a control host, a control mainboard, etc., which are arranged in an elevator control room or a control cabinet. Optionally, the host computer 700 may be a touch device such as a mobile phone, a tablet or a PC, so that the user can conveniently set and adjust system parameters through the touch device to realize data monitoring, history viewing and intelligent control.

[0069] In some embodiments, the system further includes a protection circuit that monitors the working state of the entire system and takes measures to protect the system when an abnormality is detected. In addition, the system also has a powerful data communication function, supporting multiple wired and wireless transmission methods including RS485, RS232, LoRa (Long Range Radio), Bluetooth, Zigbee (a low-speed short-distance transmission wireless network protocol), etc., and can transmit the current set by the host computer 700 and the optimized PID parameters to the current control module 300, and can upload historical data to the host computer.

[0070] In addition, in some embodiments, the current control module 300 can also output a level signal to the indicator light 500 to intuitively indicate whether the control signal is being output. The indicator light 500 can reflect the output state of the current control module 300 in real time. When the current control module 300 outputs a control signal, the indicator light 500 lights up; when the control signal stops being output, the indicator light 500 goes out.

[0071] In an exemplary embodiment, if Figure 2 As shown, the power module 100 provides 220V raw power input through an AC power source, and converts the AC power into stable DC power (24V) through a rectifier bridge, thereby providing continuous power supply for the entire system.

[0072] like Figure 2 As shown, a feedback circuit including an acquisition module 801 and a current acquisition chip 802 is used to obtain feedback signals. The acquisition module 801 directly obtains the operating status of the elevator brake and the current signal in the brake coil 200, providing an information basis for subsequent data processing. The current acquisition chip 802 can receive analog signals from the acquisition module 801, and convert these signals into digital signals through analog-to-digital conversion, and transmit the converted digital signals to the control core 301 of the current control module 300 through the digital interface SPI (serial peripheral interface).

[0073] In some embodiments, the control core 301 may be a single-chip microcomputer, etc., which is responsible for receiving and processing digital signals from the current acquisition chip 802, wherein the digital signals include the observed parameters of the corresponding brake caliper of the brake and the current value of the brake coil, etc. The observed parameters include the braking response time, the temperature of the brake disc, the wear degree and the braking distance, etc. The control core 301 also has a data storage function, for example, the control parameters are saved in the EEPROM (Electrically Erasable Programmable Read-Only Memory) 302 via I / O (input / output), and the process data is stored in the Flash (flash memory) 303 via SPI, which is convenient for subsequent data analysis and troubleshooting. In addition, the current control module 300 also has a built-in communication module 304, which supports real-time communication with the host computer 700, so as to realize monitoring, parameter adjustment and historical data viewing through the host computer 700. For example, the communication module 304 communicates with the host computer 700 through the RS485 interface and communicates with the control core 301 through the UART (Universal Asynchronous Receiver Transmitter). In this way, the control core 301 can send the observed parameters of the brake caliper and the current value of the brake coil to the host computer 700, so that the host computer 700 can optimize the PID parameters using a genetic algorithm. The optimization will be described in detail below. In some embodiments, the host computer 700 can actively obtain the feedback signal and corresponding information, data, etc. through the control core 301.

[0074] In some embodiments, the current control module 300 converts the 24V DC voltage into 3V3 (3.3V) through the power input module 305 and inputs it into the control core 301. The control core 301 performs PID control according to the optimized PID parameters received from the host computer 700 to generate a control signal. In some embodiments, the control signal is a PWM (pulse width modulation) signal. The current regulation module 400 includes a pulse width adjustment module 401 and a comparator 402. The pulse width adjustment module 401 is used to receive and process the PWM signal sent by the control core 301, and convert the PWM signal into a smoother and more stable sinusoidal PWM signal (SPWM). The comparator 402 generates a control signal by comparing the sinusoidal PWM signal with a preset reference current, and the control signal is used to control the current of the brake coil 200 to control the braking action. In an optional embodiment, the control signal output by the comparator 402 forms a discontinuous pulse sequence through a chopping operation to adjust the voltage, thereby controlling the current output to the brake coil, so that the coil current can be adjusted and controlled by changing the width of the pulse.

[0075] like Figure 3 As shown, an embodiment of the present invention provides a computer device, such as a host computer 700, which includes:

[0076] Memory 702, which stores computer-readable instructions and data, and may include memory and data storage devices;

[0077] A processor 701, which performs at least a portion of the operations of the method described in any embodiment of the present invention according to the computer-readable instructions and data to obtain optimized PID parameters;

[0078] The communication module 706 , which communicates with the processor 701 via the I / O module 707 , is configured to send the optimized PID parameters to the current control module 300 .

[0079] In an optional embodiment, the host computer 700 further includes a display 704 for monitoring, parameter adjustment and historical data viewing. In an optional embodiment, the host computer 700 may further include a speaker 705 for sounding an alarm when a brake failure or a control system error occurs.

[0080] In some embodiments, the computer device may be a mainboard, a host, a user terminal, etc. that can execute a program to perform data processing.

[0081] According to the above, an embodiment of the present invention relates to a method for controlling an elevator brake using genetic PID, wherein the elevator brake includes at least two brake calipers, and the method includes: providing a PID controller (or a current control module 300) with a current value in a brake coil 200 of each brake caliper measured in real time; using the PID controller to generate a control signal for adjusting the current supply of the brake coil of the corresponding brake caliper according to the measured current value and a preset target current value; obtaining the actual required braking force of each brake caliper during the braking process; for each brake caliper, using a genetic algorithm to optimize the PID parameters of the PID controller according to the actual required braking force of the corresponding brake caliper; and adjusting the control signal by using the optimized PID parameters through the PID controller.

[0082] In some implementations, the current value in the brake coil is measured in real time by a current sensor (eg, a feedback circuit including an acquisition module 801 and a current acquisition chip 802 ), and the current value is provided to the PID controller at a frequency of milliseconds.

[0083] In some embodiments, the generation of the control signal includes: calculating the error between the measured current and the target current; and generating the control signal according to the current error using formula (1):

[0084] (1)

[0085] in, represents the control signal, are the gain coefficients of the proportional, integral and differential links of the PID controller, Indicates the error between the current and the target current.

[0086] In some embodiments, obtaining the actual required braking force of each brake caliper during braking includes: obtaining observed parameters of each brake caliper, wherein the observed parameters include braking response time, brake disc temperature, wear and braking distance; and obtaining the actual required braking force of each brake caliper based on the obtained observed parameters.

[0087] Figure 4 An example of using a genetic algorithm to optimize the PID parameters of a PID controller is shown. In the genetic algorithm, the "initial population", i.e., the randomly generated PID parameter combination, may be far from the optimal solution, resulting in a large current error, making the braking force of each brake caliper inaccurate and unreliable; the "fitness evaluation", i.e., the actual braking force obtained by real-time monitoring of each observed parameter, can accurately evaluate whether the input control force corresponding to each individual is close to the actual braking force, so that the objective function The value of is the smallest; "selection operation" means that excellent individuals (i.e. PID parameter combinations with smaller errors) have a greater probability of being selected, thereby retaining their excellent genes; "crossover and mutation operation" means that through crossover and mutation operations, new PID parameter combinations can be generated to increase the diversity of the population and may find a better solution; "iterative optimization" means that as the number of iterations increases, the individuals in the population gradually approach the optimal solution, The value keeps decreasing; the optimal PID parameter combination finally found by "Optimization Result" can accurately control the current of the brake coil and achieve the best braking effect.

[0088] In some embodiments, Figure 4 As shown, for any j-th brake caliper of the brake ( The optimization of PID parameters of PID controller using genetic algorithm includes the following processing:

[0089] S1: Set the parameters of the genetic algorithm, including population size, crossover probability, mutation probability and maximum number of iterations, and initialize the parameter ranges of the PID controller;

[0090] S2: Randomly generate a set of PID parameters as the initial population;

[0091] S3: For each individual in the population, its PID parameters are applied to the PID controller and the response of the brake is simulated to obtain the current value corresponding to the corresponding brake caliper;

[0092] S4: Calculating the fitness value of each individual according to the actual required braking force of the brake caliper and the corresponding current value;

[0093] S5: Determine whether the termination condition is met. If so, proceed to process S6; otherwise, proceed to process S7;

[0094] S6: Stop iteration and output optimized PID parameters;

[0095] S7: Selecting a portion of individuals as parents of the next generation according to the fitness value;

[0096] S8: Perform a crossover operation on the selected parent generation to generate new offspring individuals;

[0097] S9: Perform mutation operation on the newly generated offspring individuals;

[0098] S10: Combine the offspring individuals generated after the crossover and mutation operations into a new population, replace the original population, and return to process S3.

[0099] In some embodiments of the present invention, in process S3, the individual variable is represented as: ,in, represents the i-th individual variable, i is an integer greater than 1 and less than or equal to the number of populations, a ij is the weight coefficient of the j-th brake caliper, wherein, initially, the weight coefficients of the n brake calipers are equal and the sum is 1;

[0100] Applying the individual variables to the PID controller, according to formula (1), K p , K i and K d The change in value affects The change of , in turn, affects the current change of the corresponding brake coil, and the current change affects the corresponding braking force change, so the corresponding braking force can be expressed as:

[0101] , is the input control force of the jth brake caliper, I ij is the current size corresponding to the brake caliper.

[0102] In some embodiments of the present invention, in process S4, the objective function is applied , and through the fitness function To calculate the fitness value ;

[0103] Among them, the objective function is:

[0104]

[0105] Constraints:

[0106]

[0107] is the actual braking force required by the j-th brake caliper, and F is the total force required for braking.

[0108] In some embodiments of the present invention, in process S5, when a predetermined maximum number of iterations is reached or the fitness value of the current optimal individual is the smallest, it is determined that the termination condition is met.

[0109] Through the above processing, the optimal PID parameters can be obtained, and the parameters can be provided to the current control module 300 so that its PID controller generates a control signal according to formula (1), and the real-time current of the brake coil is adjusted by the control signal, thereby adjusting the braking force to achieve the desired braking effect.

[0110] In some embodiments, the processor 701 of the host computer 700 can be configured to perform processing S1-S10 according to the computer-readable instructions and data to obtain optimized PID parameters. In an optional embodiment, the processor 701 can be configured to perform all the processing in the method of controlling a multi-caliper disc elevator brake using genetic PID according to the computer-readable instructions and data.

[0111] For ease of understanding, it is assumed that the brake current of the brake system needs to be precisely controlled at 2A to ensure the best braking effect. A current sensor is set to monitor the current in the brake coil in real time, and the target current value is set to 2A.

[0112] The current in the brake coil is measured in real time by a current sensor, and the data is fed back to a PID controller (which may be included in or implemented by the current control module 300) at a frequency of milliseconds. The PID controller calculates and outputs a control signal to adjust the current of the brake coil based on the data fed back by the current sensor and the preset target current value (2A). Specifically, the relationship between the parameters (Kp, Ki, Kd) of the PID controller and the output current can be reflected by formula (1).

[0113] The actual braking force required by each brake caliper is obtained by real-time monitoring of observed parameters (such as brake response time, brake disc temperature, wear and braking distance). represents the actual required braking force of the jth brake caliper.

[0114] Using genetic algorithm, for the jth brake caliper, the parameters (Kp, Ki, Kd) and weight coefficient a of the PID controller are optimized by iteration. ij , obtain the required control current I ij , so that the corresponding brake caliper can achieve accurate and reliable braking.

[0115] Among them, the optimization process using genetic algorithm includes:

[0116] 1. Initialize the population:

[0117] • Randomly generate a set of PID parameters as the initial population, for example: Kp=1.0, Ki=0.1, Kd=0.01 (these values ​​are only examples and may differ in practice).

[0118] • The population size is set to 20 individuals, each of which represents a set of potential PID parameter combinations.

[0119] 2. Fitness evaluation:

[0120] • Apply each individual in the current population (i.e. each set of PID parameters) to the PID controller.

[0121] • Monitor and record the current value in the brake coil in real time through the current sensor.

[0122] • Calculate the fitness value of each individual. The fitness function can be defined as , the smaller its value is, the better the population obtained is.

[0123] 3. Select an action:

[0124] • Select excellent individuals for reproduction based on fitness values.

[0125] 4. Crossover operation:

[0126] • The selected individuals generate new offspring through crossover operation. For example, using the single-point crossover method, a crossover point is randomly selected, and then the genes (i.e. PID parameters) of the two parent individuals after the crossover point are exchanged.

[0127] 5. Mutation operation:

[0128] • Perform random mutations on the newly generated offspring to increase the diversity of the population. For example, randomly change the value of a gene (i.e., PID parameter) of the offspring individual with a certain probability (such as 0.01).

[0129] 6. Formation of a new generation of population:

[0130] • Combine the individuals after selection, crossover and mutation into a new population.

[0131] 7. Iterative optimization:

[0132] • Repeat steps 2 to 6 for multiple iterations. After each iteration, record the individual with the highest fitness in the current population (i.e., the optimal PID parameter combination) and its corresponding current error.

[0133] 8. Termination Conditions:

[0134] • The iteration is terminated when the predetermined number of iterations (such as 100) is reached or the fitness value of the current optimal individual is the smallest.

[0135] Optimization results and analysis: After multiple iterations, the genetic algorithm found an optimal PID parameter combination, for example: Kp = 1.5, Ki = 0.2, Kd = 0.02. At this time, the current in the brake coil is accurately controlled at about 2A, the current error is very small (less than 0.01A), and the system has good stability and response speed, and each brake caliper achieves accurate and reliable braking.

[0136] Through this example, genetic algorithm can be used as an effective optimization tool to improve the control performance and stability of elevator braking system.

[0137] It should be noted that the methods and steps, processing or operations described in each embodiment of the present invention can be programmed and stored on a computer-readable storage medium. Therefore, the embodiments of the present invention also relate to a computer program product and a computer-readable storage medium thereof. The computer-readable storage medium stores computer-readable instructions or programs of the computer program product, which are executed by one or more processors to perform the processing, operation or steps of the method described in any embodiment or example of the present invention, for example, all or any part of the operations in S1-S10 can be performed.

[0138] Those skilled in the art should understand that what is disclosed above is only an implementation mode of the present invention, and it certainly cannot be used to limit the scope of rights for patent protection requested by the present invention. Equivalent changes made according to the implementation mode of the present invention are still within the scope covered by the claims of the present invention.

Claims

1. A method for controlling an elevator brake using genetic PID, the elevator brake comprising at least two brake calipers, the method comprising: Providing the PID controller with the current value in the brake coil of each brake caliper measured in real time; generating, using the PID controller, a control signal for adjusting the current supply to the brake coil of the corresponding brake caliper according to the measured current value and a preset target current value; Obtain the actual required braking force of each brake caliper during braking; For each brake caliper, according to the actual required braking force of the corresponding brake caliper, a PID parameter of the PID controller is optimized using a genetic algorithm; adjusting the control signal using optimized PID parameters by the PID controller; Wherein, the generation of the control signal includes: Calculate the error between the measured current and the target current; According to the current error, the control signal is generated using formula (1): （1） in, represents the control signal, are the gain coefficients of the proportional, integral and differential links of the PID controller, Indicates the error between the current and the target current; Wherein, the elevator brake comprises n brake calipers, where n is an integer greater than 1; For any j-th brake caliper, the optimization of the PID parameters of the PID controller includes the following processing: S1: Set the parameters of the genetic algorithm, including population size, crossover probability, mutation probability and maximum number of iterations, and initialize the parameter ranges of the PID controller; S2: Randomly generate a set of PID parameters as the initial population; S3: for each individual in the population, applying its PID parameter to the PID controller and simulating the response of the brake to obtain the current value corresponding to the j-th brake caliper; S4: Calculate the fitness value of each individual according to the actual required braking force of the j-th brake caliper and the corresponding current value; S5: Determine whether the termination condition is met. If so, proceed to process S6; otherwise, proceed to process S7; S6: Stop iteration and output optimized PID parameters; S7: Selecting a portion of individuals as parents of the next generation according to the fitness value; S8: Perform a crossover operation on the selected parent generation to generate new offspring individuals; S9: Perform mutation operation on the newly generated offspring individuals; S10: Combine the offspring individuals generated after the crossover and mutation operations into a new population, replace the original population, and return to process S3; In treatment S3, individual variables are represented as: ,in, represents the i-th individual variable, i is an integer greater than 1 and less than or equal to the number of populations, a ij is the weight coefficient of the j-th brake caliper, wherein, initially, the weight coefficients of the n brake calipers are equal and the sum is 1; Applying the individual variables to the PID controller, according to formula (1), K p , K i and K d The change in value affects The change of will affect the current change of the corresponding brake coil, so the corresponding braking force is expressed as: , is the input control force of the jth brake caliper, I ij is the current size corresponding to the brake caliper.

2. The method of claim 1, wherein: The current value in the brake coil is measured in real time by a current sensor, and the current value is provided to the PID controller at a frequency of milliseconds.

3. The method of claim 1, wherein: The actual required braking force of each brake caliper during the braking process is obtained by: Obtaining observation parameters of each brake caliper, wherein the observation parameters include brake response time, brake disc temperature, wear and braking distance; According to the obtained observation parameters, the actual required braking force of each brake caliper is obtained.

4. The method of claim 1, wherein: In process S4, the objective function is applied , and through the fitness function To calculate the fitness value ; Among them, the objective function is: Constraints: is the actual braking force required by the j-th brake caliper, and F is the total force required for braking.

5. The method of claim 1, wherein: In process S5, when the predetermined number of iterations is reached or the fitness value of the current optimal individual is the smallest, it is determined that the termination condition is met.

6. A system for controlling an elevator brake using genetic PID, comprising: A power supply module, which provides working current for the brake; A brake coil configured to generate an electromagnetic force when current flows therethrough to control each brake caliper of the brake; a current control module configured to generate a control signal for controlling the current supply of the brake coil using a genetic PID controller, and receive a current signal of the brake coil fed back; a current regulating module, configured to receive a control signal from the current control module to regulate the current output by the power module, and output the regulated current to the brake coil; A host computer is configured to execute the method described in any one of claims 1 to 5 to obtain optimized PID parameters, and provide the parameters to the current control module.

7. A computer device comprising: a memory storing computer-readable instructions and data; A processor, which executes at least a portion of the operations of the method described in any one of claims 1 to 5 according to the computer-readable instructions and data to obtain optimized PID parameters; A communication module is configured to send the optimized PID parameters to a current control module.

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