An emulsion pump loading valve speed control system and working method thereof

Abstract

The application discloses an emulsion pump loading valve speed regulation control system and a working method thereof. The emulsion pump loading valve speed regulation control system comprises a servo motor, a servo driver and an upper computer. The working method comprises the following steps: S1, inputting a pressure setting value of the emulsion pump loading valve; S2, the upper computer calculating the inputted pressure setting value of the emulsion pump loading valve through a PID controller, obtaining a required rotating state and a required rotating speed of the servo motor and transmitting the required rotating state and the required rotating speed to the servo driver; S3, the servo driver controlling the servo motor, so that the servo motor drives the emulsion pump loading valve to work; S4, a pressure sensor feeding back the pressure collection value to the upper computer; S5, the upper computer comparing and calculating the pressure parameter of the emulsion pump loading valve through the PID controller; and S6, the servo driver adjusting and controlling the servo motor according to the comparison and calculation result, so that the pressure of the emulsion pump loading valve is accurately controlled.

Description

Technical Field

[0001] This invention relates to the field of emulsion pumps, and more particularly to a speed control system for an emulsion pump loading valve and its operating method. Background Technology

[0002] Coal, as a vital energy resource, plays a crucial role in the national energy structure and has a profound impact on the economy and people's lives. Although the proportion of coal in energy production is gradually decreasing, it still dominates industrial production and residential consumption. With the continuous development of coal mining technology, emulsion pumps for thick coal seam fully mechanized mining faces are constantly evolving towards higher pressure and larger flow rates, making the demand for design pressure and flow rates of domestically produced emulsion pumps increasingly urgent.

[0003] The commonly used automated control solutions for emulsion pumps on the market mainly include the following:

[0004] PLC Control System: Many emulsion pump systems are controlled using programmable logic controllers (PLCs). This approach typically combines sensors and actuators, using programming to control and monitor the loading valve. While PLC systems can achieve a certain degree of automation, their response speed and control accuracy are often inferior to servo motor systems based on a host computer.

[0005] PID control scheme: Some existing technologies use PID (proportional-integral-derivative) control algorithms to adjust the opening of the loading valve. This scheme adjusts the valve by monitoring pressure and flow in real time, but when faced with complex working conditions, there may be problems of adjustment lag and insufficient accuracy, and the PID parameters are not accurate enough.

[0006] Industrial robot control system: Some emulsion pump systems use industrial robots to operate valves precisely. Although this solution has high flexibility, its application is limited due to its complexity and cost.

[0007] Control schemes based on embedded systems: Some schemes use embedded controllers to monitor and control the loading valve. These systems typically have low cost and power consumption, but their ability to handle complex control logic and data analysis is relatively limited.

[0008] LabVIEW-based software control scheme: Some research and industrial applications use software platforms such as LabVIEW to control loading valves. Although this scheme has advantages in data acquisition and processing, it may not be able to achieve the level of real-time control accuracy and response speed as the host computer controlling the servo motor.

[0009] In summary, the existing solutions described above have achieved control of the loading valve of the emulsion pump to varying degrees, but they still have certain limitations in terms of control accuracy, dynamic response, and safety, and it is necessary to improve them. Summary of the Invention

[0010] The purpose of this invention is to address the above-mentioned problems by providing an emulsion pump loading valve speed control system and its operating method that achieves automated control and reduces human error rate.

[0011] To achieve the above objectives, the technical solution of the present invention is as follows:

[0012] A speed control system for an emulsion pump loading valve includes a servo motor for powering the emulsion pump loading valve, a servo driver for monitoring and controlling the rotation state and speed of the servo motor, and a host computer for transmitting control signals to the servo driver and receiving servo motor status feedback information. The host computer and the servo driver are connected via a 485 communication interface for data transmission. The servo driver is connected to the servo motor via wiring to enable the servo motor to rotate. The servo motor is driven by the emulsion pump loading valve to achieve the pumping loading effect of the emulsion pump loading valve. A pressure sensor for collecting the outlet pressure is fixedly connected to the outlet position of the emulsion pump loading valve, and the pressure sensor is connected to the host computer to transmit pressure data.

[0013] Furthermore, an encoder is provided between the servo driver and the servo motor, and the servo motor is controlled by the encoder signal.

[0014] Furthermore, a reduction mechanism and a coupling mechanism are provided between the servo motor and the emulsion pump loading valve, and the servo motor is connected to the emulsion pump loading valve through the reduction mechanism and the coupling mechanism in sequence.

[0015] Furthermore, the reduction mechanism is a planetary gear reducer.

[0016] Furthermore, the coupling mechanism is one of the following: a gear transmission mechanism, a cam transmission mechanism, a coupling transmission mechanism, or a synchronous belt transmission mechanism.

[0017] A method for operating a speed control system for an emulsion pump loading valve includes the following steps:

[0018] S1. The operator inputs the pressure setting value of the emulsion pump loading valve into the user interface of the host computer;

[0019] S2. The host computer calculates the input emulsion pump loading valve pressure setting value through the PID controller, obtains the required rotation state and required speed of the servo motor, and transmits it to the servo driver.

[0020] S3. The servo driver controls the servo motor according to the required rotation state and speed of the servo motor, so that the servo motor drives the emulsion pump loading valve to work.

[0021] S4. The pressure sensor in the emulsion pump loading valve monitors the pressure acquisition value of the emulsion pump loading valve and feeds the pressure acquisition value back to the host computer.

[0022] S5. The host computer compares and adjusts the pressure setpoint and pressure acquisition value of the emulsion pump loading valve through the PID controller, obtains the adjustment rotation state and adjustment speed of the servo motor, and transmits them to the servo driver. At the same time, the data is stored in the TD database for easy PID parameter analysis.

[0023] S6. The servo driver controls the servo motor based on the received servo motor adjustment rotation state and servo motor adjustment speed, so that the servo motor drives the emulsion pump loading valve to work, and finally makes the pressure acquisition value of the emulsion pump loading valve reach the pressure set value of the emulsion pump loading valve, thereby realizing precise pressure control of the emulsion pump loading valve.

[0024] Furthermore, in step S5, the adjustment of the pressure setpoint of the emulsion pump loading valve compared with the pressure acquisition value of the emulsion pump loading valve specifically includes the following steps:

[0025] S51. Compare the pressure setpoint with the pressure acquisition value;

[0026] S52. Determine if there is a pressure setpoint = 0 or a pressure acquisition value > 0; if so, set the servo motor adjustment speed to 1000rpm, perform PID parameter settings, and cause the servo motor to reverse; if not, proceed to the next step.

[0027] S53. Determine whether the pressure setpoint is greater than the pressure acquisition value; if the pressure setpoint is greater than the pressure acquisition value, proceed to the next step; if the pressure setpoint is not greater than the pressure acquisition value, proceed to step S55.

[0028] S54. Set the servo motor's adjustment speed based on the pressure acquisition value; when 45 ≤ pressure acquisition value < 50, set the servo motor's adjustment speed to 400 rpm, perform PID parameter settings, and cause the servo motor to reverse; when 40 ≤ pressure acquisition value < 45, set the servo motor's adjustment speed to 500 rpm, perform PID parameter settings, and cause the servo motor to reverse; when 35 ≤ pressure acquisition value < 40, set the servo motor's adjustment speed to 600 rpm, perform PID parameter settings, and cause the servo motor to reverse; when 30 ≤ pressure acquisition value < 35, set the servo motor's adjustment speed to 700 rpm. At 00 rpm, set the PID parameters to cause the servo motor to reverse; when 20 ≤ pressure acquisition value < 30, set the servo motor's adjustment speed to 800 rpm and set the PID parameters to cause the servo motor to reverse; when 10 ≤ pressure acquisition value < 20, set the servo motor's adjustment speed to 900 rpm and set the PID parameters to cause the servo motor to reverse; when 0 < pressure acquisition value < 10, set the servo motor's adjustment speed to 1000 rpm and set the PID parameters to cause the servo motor to reverse; when the pressure acquisition value = 0, set the servo motor's adjustment speed to 0 rpm.

[0029] S55. Set the servo motor's adjustment speed based on the pressure acquisition value; when 0 < pressure acquisition value ≤ 10, set the servo motor's adjustment speed to 1000 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 10 < pressure acquisition value ≤ 20, set the servo motor's adjustment speed to 900 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 20 < pressure acquisition value ≤ 30, set the servo motor's adjustment speed to 800 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 30 < pressure acquisition value ≤ 35, set the servo motor's adjustment speed to 7... 00rpm, set the PID parameters to make the servo motor rotate forward; when 35 < pressure acquisition value ≤ 40, set the servo motor adjustment speed to 600rpm, set the PID parameters to make the servo motor rotate forward; when 40 < pressure acquisition value ≤ 45, set the servo motor adjustment speed to 500rpm, set the PID parameters to make the servo motor rotate forward; when 45 < pressure acquisition value < 50, set the servo motor adjustment speed to 400rpm, set the PID parameters to make the servo motor rotate forward; when the pressure acquisition value ≥ 50, set the servo motor adjustment speed to 0rpm.

[0030] Furthermore, the PID parameters are optimized using the Ziegler-Nichols method; this specifically includes the following steps:

[0031] S511. Convert the current PID controller to proportional control mode, and adjust the integral gain K. i and differential gain K d Set to zero;

[0032] S512, Gradually increase the proportional gain K p Until it exhibits continuous oscillation, at which point the proportional gain K... p That is, the critical gain K. u ;

[0033] S513, at the proportional gain K p Reaching the critical gain K u At that time, record the oscillation period T. u ;

[0034] S514, Using Critical Gain K u and oscillation period T u The PID parameters of the PID controller are calculated using the following formula:

[0035] P control: K p =K u ;

[0036] PI control: K p =0.45K u ,

[0037] PID control: K p =0.6K u ,

[0038] Based on the analysis of the experimental data, the following conclusions were drawn:

[0039] K u =20,T u =5s.

[0040] Compared with the prior art, the advantages and positive effects of this invention are:

[0041] 1. Simplified wiring complexity: This invention optimizes electrical connections and simplifies the installation process through centralized management and control by a host computer, making system maintenance and expansion more convenient. Users can easily adjust and upgrade the system, ensuring higher system flexibility and reliability.

[0042] 2. Digital storage of experimental data: This invention upgrades experimental data from traditional visual observation to database storage via a host computer. This innovation enables real-time acquisition, storage, and convenient access to all experimental data. Users can review and access historical experimental data at any time, facilitating system performance evaluation and optimization analysis. This digital management ensures the accuracy and integrity of the data, providing a reliable foundation for subsequent data processing.

[0043] 3. PID Parameter Optimization Based on Data Analysis: This invention analyzes experimental data stored in a database and uses scientific methods to automatically extract key features to determine more accurate and adaptable PID parameters. This data analysis-based optimization method significantly improves control accuracy and ensures that the servo motor system can achieve the best control effect in different working environments.

[0044] 4. This invention uses a host computer to control a servo motor, enabling rapid and precise control of the emulsion pump loading valve to adapt to complex and rapidly changing working conditions. At the same time, automated control reduces the risks associated with manual operation, thereby improving the safety and reliability of the entire system. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of the hardware connection of the present invention;

[0047] Figure 2 This is a schematic diagram of the pressure interface of the present invention;

[0048] Figure 3 This is a flowchart of the control logic for the loading valve of the emulsion pump. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art to all other embodiments obtained without creative effort should be included within the protection scope of the present invention.

[0050] This invention discloses a speed control system for an emulsion pump loading valve, the application of which in speed control of the emulsion pump loading valve meets the needs of precise motor control in the field of industrial automation.

[0051] The emulsion pump loading valve speed control system includes a servo motor for powering the emulsion pump loading valve, a servo driver for monitoring and controlling the rotation state and speed of the servo motor, and a host computer for transmitting control signals to the servo driver and receiving servo motor status feedback information.

[0052] The host computer and the servo driver are connected via a 485 communication interface to achieve data transmission; the servo driver is connected to the servo motor circuit via an encoder to enable the servo motor to rotate; the servo motor is connected to the emulsion pump loading valve to achieve the pumping loading effect of the emulsion pump loading valve; a pressure sensor for collecting the outlet pressure is fixedly connected to the outlet position of the emulsion pump loading valve, and the pressure sensor is connected to the host computer to achieve pressure data transmission.

[0053] The working method of the above system is as follows:

[0054] S1. The operator inputs the pressure setting value of the emulsion pump loading valve into the user interface of the host computer;

[0055] S2. The host computer calculates the input emulsion pump loading valve pressure setting value through the PID controller, obtains the required rotation state and required speed of the servo motor, and transmits it to the servo driver.

[0056] S3. The servo driver controls the servo motor according to the required rotation state and speed of the servo motor, so that the servo motor drives the emulsion pump loading valve to work.

[0057] S4. The pressure sensor in the emulsion pump loading valve monitors the pressure acquisition value of the emulsion pump loading valve and feeds the pressure acquisition value back to the host computer.

[0058] S5. The host computer compares and adjusts the pressure setpoint and pressure acquisition value of the emulsion pump loading valve through the PID controller, obtains the adjustment rotation state and adjustment speed of the servo motor, and transmits them to the servo driver. At the same time, the data is stored in the TD database for easy PID parameter analysis.

[0059] S6. The servo driver controls the servo motor based on the received servo motor adjustment rotation state and servo motor adjustment speed, so that the servo motor drives the emulsion pump loading valve to work, and finally makes the pressure acquisition value of the emulsion pump loading valve reach the pressure set value of the emulsion pump loading valve, thereby realizing precise pressure control of the emulsion pump loading valve.

[0060] The system design in this invention mainly involves two key aspects: hardware and software, in order to ensure the high efficiency and stable operation of the motor.

[0061] In terms of hardware design, the construction of the sensor interface circuit is crucial. This circuit can accurately acquire the motor's speed and position information, providing accurate feedback data for the control system. Simultaneously, the design of the control circuit lays a solid foundation for the generation and transmission of motor control signals, ensuring signal reliability and stability.

[0062] In terms of software programming, the implementation of the control algorithm is the core of the system. Commonly used PID control algorithms can dynamically adjust the control output based on actual feedback signals, thereby achieving precise regulation of the motor speed. Furthermore, to enhance the user experience, the system features a user-friendly interface, allowing users to easily set target speeds and monitor the motor status in real time. All data is stored in the TD database for easy analysis of PID parameters. The coordinated design and optimization of the overall system directly impact the motor's performance and stability.

[0063] Hardware connection

[0064] To achieve high-precision positioning control of servo motors by a host computer, a robust hardware connection is crucial. A typical hardware connection scheme should include a reliable interface between the host computer and the servo driver, as well as an effective connection between the servo motor and the controlled object. Optimizing these connections ensures the stability and response speed of the control system, thereby improving overall control accuracy.

[0065] The host computer controls the servo drive via RS-485 communication, using commands such as start and stop. Simultaneously, the motion feedback signals (such as torque, speed, and position) of the servo drive must be connected to the host computer via the RS-485 interface to allow the host computer to monitor the actual operating status of the servo system in real time. This connection method ensures that the host computer accurately obtains motion feedback information, thereby achieving dynamic monitoring and precise control of the servo system. The servo motor is typically connected to the loading valve via a coupling device to achieve effective transmission of control force or motion. The coupling device can be selected from gears, cams, couplings, and synchronous belts, depending on the specific application scenario. In applications requiring high speed control precision, the servo motor typically uses a reduction mechanism (such as a planetary gear reducer) to drive the load, thereby achieving precise motion control. The power supply provides stable and reliable power to the servo drive and other key components, ensuring that these components operate normally under the required voltage and current conditions. For high-power servo motor systems, a dedicated power supply may be required to meet their specific power needs. Meanwhile, as the connecting link between various parts of the servo system, including power cables, control cables, and encoder cables, the selection of cables is also crucial. To ensure the stability and safety of the system, it is essential to select the appropriate cable type and properly handle critical details such as terminal connections and shielding grounding.

[0066] Hardware connection such as Figure 1 As shown, by correctly connecting the hardware, the PLC is organically combined with components such as servo motors, servo drives, and encoders to build a complete closed-loop control system, thus laying a solid hardware foundation for achieving precise position control. In this process, a reasonable hardware topology, reliable electrical connections, and scientific component selection are all important prerequisites for ensuring the efficient and stable operation of the system. These elements complement each other, jointly improving the system's performance and reliability.

[0067] Host computer programming

[0068] (1) Control algorithm optimization

[0069] In its implementation, this invention focuses on the experimental verification and optimization of the control algorithm to ensure stable and accurate speed regulation. First, a classic PID control algorithm was implemented and applied to a servo motor speed regulation system. By adjusting the PID parameters, the impact of different parameter combinations on system performance was explored, and the stability and accuracy of the control algorithm were evaluated by comparing the deviation between the actual speed and the target speed. Next, parameter adjustment experiments were conducted to further optimize the control algorithm. Through system performance testing and analysis of experimental data, the proportional, integral, and derivative gains were gradually adjusted to achieve a more ideal speed regulation effect. Experimental results show that after parameter optimization, overshoot and oscillation phenomena were effectively suppressed, and the speed regulation performance of the motor was significantly improved. Finally, by comparing the PID control algorithm with other advanced control methods, such as fuzzy control and adaptive control, the impact of different control algorithms on system performance was evaluated, as shown in Table 1.

[0070] Table 1 Speed ​​Regulation Performance of Different Algorithms

[0071] Algorithm Name Performance indicators Speed ​​adjustment effect Adjusting PID parameters for control Overshoot reduced, stability improved Improved stability and accuracy Fuzzy control Smaller error, slower response time Stable speed regulation, slow response Adaptive control Small overshoot and fast response speed Fast response and stable speed adjustment

[0072] (2) Host computer code writing

[0073] In speed control systems, the code structure is divided into two main parts: device agents and user interfaces. Device agents act as the interaction bridge between the system and hardware devices, while the user interface provides the operator with intuitive control and monitoring functions. The following is a detailed description of these two parts:

[0074] The core function of the device agent is to communicate with the servo drive via the MODBUS RTU protocol. MODBUS RTU is a widely used serial communication protocol suitable for data transmission between devices in industrial automation. It performs read and write operations on specific register addresses of the servo drive. These registers are typically used to store control commands and status data. Through precise register addresses, the system can perform the following operations:

[0075] Start and Stop: Send the corresponding signal to the driver to start or stop the servo motor.

[0076] Forward and reverse rotation control: By setting specific control positions, the rotation direction of the servo motor can be changed to meet different process requirements.

[0077] Speed ​​setting: Write the target speed value into the driver register to adjust the motor running speed.

[0078] Fault information monitoring: Periodically read the driver's status register to obtain fault information and address potential problems in a timely manner.

[0079] Parameter settings: PID parameter settings.

[0080] The user interface serves as the interaction layer between the operator and the control system, designed to provide convenient operation and real-time status feedback. The interface allows users to directly input the desired pressure value. The system compares this input pressure with the real-time collected pressure values, automatically calculates the corresponding servo motor operating parameters, and sets the pressure interface as shown below. Figure 2 As shown.

[0081] In summary, the device agent and user interface complement each other, together forming an efficient and reliable servo control system. The device agent is responsible for low-level hardware control of the servo driver via the MODBUS RTU protocol, while the user interface provides a user-friendly operating environment, ensuring that users can easily set parameters, monitor status, and troubleshoot problems. This architecture not only improves the system's flexibility and operability but also enhances the overall security and stability of the servo control system.

[0082] The logic flowchart of the code-controlled loading valve is as follows: Figure 3 As shown, it mainly includes the following steps:

[0083] 1. Compare the pressure setpoint of the emulsion pump loading valve with the pressure collected value of the emulsion pump loading valve;

[0084] 2. Determine if there is a pressure setpoint of 0 or a pressure acquisition value greater than 0; if so, set the servo motor's adjustment speed to 1000 rpm, perform PID parameter settings, and cause the servo motor to reverse; if not, proceed to the next step.

[0085] 3. Determine if the pressure setpoint is greater than the pressure acquisition value; if the pressure setpoint is greater than the pressure acquisition value, proceed to the next step; if the pressure setpoint is not greater than the pressure acquisition value, proceed to step 5.

[0086] 4. Set the servo motor's adjustment speed based on the pressure acquisition value; when 45 ≤ pressure acquisition value < 50, set the servo motor's adjustment speed to 400 rpm and configure the PID parameters to reverse the servo motor; when 40 ≤ pressure acquisition value < 45, set the servo motor's adjustment speed to 500 rpm and configure the PID parameters to reverse the servo motor; when 35 ≤ pressure acquisition value < 40, set the servo motor's adjustment speed to 600 rpm and configure the PID parameters to reverse the servo motor; when 30 ≤ pressure acquisition value < 35, set the servo motor's adjustment speed to 70 rpm. At 0 rpm, set the PID parameters to cause the servo motor to reverse; when 20 ≤ pressure acquisition value < 30, set the servo motor's adjustment speed to 800 rpm and set the PID parameters to cause the servo motor to reverse; when 10 ≤ pressure acquisition value < 20, set the servo motor's adjustment speed to 900 rpm and set the PID parameters to cause the servo motor to reverse; when 0 < pressure acquisition value < 10, set the servo motor's adjustment speed to 1000 rpm and set the PID parameters to cause the servo motor to reverse; when the pressure acquisition value = 0, set the servo motor's adjustment speed to 0 rpm.

[0087] 5. Set the servo motor's adjustment speed based on the pressure acquisition value; when 0 < pressure acquisition value ≤ 10, set the servo motor's adjustment speed to 1000 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 10 < pressure acquisition value ≤ 20, set the servo motor's adjustment speed to 900 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 20 < pressure acquisition value ≤ 30, set the servo motor's adjustment speed to 800 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 30 < pressure acquisition value ≤ 35, set the servo motor's adjustment speed to 70... Set the PID parameters to 0 rpm to make the servo motor rotate forward; when 35 < pressure acquisition value ≤ 40, set the servo motor adjustment speed to 600 rpm and set the PID parameters to make the servo motor rotate forward; when 40 < pressure acquisition value ≤ 45, set the servo motor adjustment speed to 500 rpm and set the PID parameters to make the servo motor rotate forward; when 45 < pressure acquisition value < 50, set the servo motor adjustment speed to 400 rpm and set the PID parameters to make the servo motor rotate forward; when the pressure acquisition value ≥ 50, set the servo motor adjustment speed to 0 rpm.

[0088] Data storage and PID parameter calculation

[0089] In modern control systems, especially in servo motor speed control applications, real-time acquisition and storage of system operating data is of great significance. By storing the actual rotational speed and the corresponding response time during execution in a database, the parameter settings of the PID control algorithm can be analyzed more comprehensively and in-depth, and system performance can be further optimized.

[0090] Analyzing the deviation between the actual and target speeds allows for a more intuitive evaluation of the algorithm's control effectiveness. For example, if significant overshoot, oscillation, or steady-state error is found under certain PID parameter settings, engineers can adjust the proportional, integral, and derivative gain values ​​accordingly to optimize control performance. Measuring response time helps researchers analyze the system's dynamic characteristics. By comparing the response times under different PID parameter settings, it's possible to determine which set of parameters can bring the system to the target state within the target time, thereby improving the overall system efficiency. Pay particular attention to the experimental results of the PID parameters shown in Table 2.

[0091] Table 2. PID Parameter Settings and Effects

[0092]

[0093] Experimental results show that the PID parameters of Group 1 can quickly and accurately adjust the actual speed to near or reach the target speed. Next, the parameters of Group 1 will be further refined and optimized using the Ziegler-Nichols method, as follows:

[0094] 1. Set the feedback controller to P control mode;

[0095] Convert the current PID controller to proportional (P) control mode, and set K... i and K d Set it to zero. The purpose of this step is to find the critical gain K of the system. u and critical period T u .

[0096] 2. Adjust the proportional gain (K) p );

[0097] Gradually increase the proportional gain (K) p The gain value is calculated until the system exhibits continuous oscillation (i.e., the system fluctuates back and forth after reaching the set point). This gain value is the critical gain K. u .

[0098] 3. Measure the period of oscillation;

[0099] In K p Reaching K u At that time, record the oscillation period T of the system. u .

[0100] 4. Calculate the PID parameters;

[0101] Based on the Ziegler-Nichols empirical formula, using the recorded K... u and T u To calculate the PID parameters, the classic Ziegler-Nichols method uses the following formula:

[0102] P control: K p =K u

[0103] PI control: K p =0.45K u ,

[0104] PID control: K p =0.6K u ,

[0105] After analyzing data from multiple experiments, the following conclusions were drawn:

[0106] K u =20,T u =5s

[0107] Based on the above calculations, the optimized parameters for Group 1 are shown in Table 3:

[0108] Table 3 Optimized Parameters

[0109] PID type proportional gain Integral gain Differential gain P 20 0 0 PI 9 4.8 0 PID 12 8 12.5

[0110] The Ziegler-Nichols method effectively refines and optimizes initial PID parameters, resulting in parameter settings more suitable for specific applications. During optimization, continuous testing and adjustments are necessary to ensure the system always operates at its optimal state.

[0111] The present invention has the following advantages:

[0112] 1. Precise control: This invention constructs an efficient feedback system. By installing a pressure sensor at the outlet of the loading valve, the position and status of the control valve are monitored in real time, ensuring that the control strategy can be adjusted quickly, thereby achieving precise control.

[0113] 2. Dynamic response: This invention improves the speed at which the servo motor responds to changes in the control loading valve at different pressure stages (0-10MPa, 10-20MPa, 20-30MPa, 30-35MPa, 35-40MPa, 40-45MPa, 45-50MPa) to adapt to rapidly changing working conditions.

[0114] 3. Data Storage: Accurate monitoring of actual speed and response time is fundamental to evaluating control effectiveness during servo motor speed regulation. Actual speed reflects the motor's operating state, while response time is the system's reaction speed to changes in control input. By storing speed and response time in the TD database, analyzing the comparison between actual and target speeds and the response time allows for better derivation of PID parameters to meet customer needs.

[0115] 4. Human-Machine Interface: This invention optimizes the user interface of the host computer, making operation simpler and more intuitive, while providing necessary monitoring and control functions to enhance the user experience.

[0116] Through the above-described operations, this invention can significantly improve the working efficiency and stability of the emulsion pump loading valve, effectively reduce the potential risks brought about by manual control of the loading valve, and thus improve the safety of the entire working process. It can better meet the needs of high efficiency, safety and precision, has significant technical advantages, and provides important technical support for applications in related industries.

Claims

1. A method for operating a speed control system for an emulsion pump loading valve, characterized in that: The emulsion pump loading valve speed control system includes a servo motor for powering the emulsion pump loading valve, a servo driver for monitoring and controlling the rotation state and speed of the servo motor, and a host computer for transmitting control signals to the servo driver and receiving servo motor status feedback information. The host computer and the servo driver are connected via a 485 communication interface for data transmission. The servo driver is connected to the servo motor via wiring to enable the servo motor to rotate. The servo motor is connected to the emulsion pump loading valve to achieve the pumping loading effect. A pressure sensor for collecting the outlet pressure is fixedly connected to the outlet position of the emulsion pump loading valve, and the pressure sensor is connected to the host computer to transmit pressure data. The working method of the emulsion pump loading valve speed control system includes the following steps: S1. The operator inputs the pressure setting value of the emulsion pump loading valve into the user interface of the host computer; S2. The host computer calculates the input emulsion pump loading valve pressure setting value through the PID controller, obtains the required rotation state and required speed of the servo motor, and transmits it to the servo driver. S3. The servo driver controls the servo motor according to the required rotation state and speed of the servo motor, so that the servo motor drives the emulsion pump loading valve to work. S4. The pressure sensor in the emulsion pump loading valve monitors the pressure acquisition value of the emulsion pump loading valve and feeds the pressure acquisition value back to the host computer. S5. The host computer compares and adjusts the pressure setpoint and pressure acquisition value of the emulsion pump loading valve through the PID controller, obtains the adjustment rotation state and adjustment speed of the servo motor, and transmits them to the servo driver. At the same time, the data is stored in the TD database for easy PID parameter analysis. S6. The servo driver controls the servo motor according to the received servo motor adjustment rotation state and servo motor adjustment speed, so that the servo motor drives the emulsion pump loading valve to work, and finally makes the pressure acquisition value of the emulsion pump loading valve reach the pressure set value of the emulsion pump loading valve, thereby realizing precise pressure control of the emulsion pump loading valve. In step S5, the adjustment of the pressure setpoint of the emulsion pump loading valve compared with the pressure acquisition value of the emulsion pump loading valve specifically includes the following steps: S51. Compare the pressure setpoint with the pressure acquisition value; S52. Determine if there is a pressure setpoint = 0 or a pressure acquisition value > 0; if so, set the servo motor adjustment speed to 1000rpm, perform PID parameter settings, and cause the servo motor to reverse; if not, proceed to the next step. S53. Determine whether the pressure setpoint is greater than the pressure acquisition value; if the pressure setpoint is greater than the pressure acquisition value, proceed to the next step; if the pressure setpoint is not greater than the pressure acquisition value, proceed to step S55. S54. Set the servo motor's adjustment speed based on the pressure acquisition value; when 45 ≤ pressure acquisition value < 50, set the servo motor's adjustment speed to 400 rpm, perform PID parameter settings, and cause the servo motor to reverse; when 40 ≤ pressure acquisition value < 45, set the servo motor's adjustment speed to 500 rpm, perform PID parameter settings, and cause the servo motor to reverse; when 35 ≤ pressure acquisition value < 40, set the servo motor's adjustment speed to 600 rpm, perform PID parameter settings, and cause the servo motor to reverse; when 30 ≤ pressure acquisition value < 35, set the servo motor's adjustment speed to 700 rpm. At 00 rpm, set the PID parameters to cause the servo motor to reverse; when 20 ≤ pressure acquisition value < 30, set the servo motor's adjustment speed to 800 rpm and set the PID parameters to cause the servo motor to reverse; when 10 ≤ pressure acquisition value < 20, set the servo motor's adjustment speed to 900 rpm and set the PID parameters to cause the servo motor to reverse; when 0 < pressure acquisition value < 10, set the servo motor's adjustment speed to 1000 rpm and set the PID parameters to cause the servo motor to reverse; when the pressure acquisition value = 0, set the servo motor's adjustment speed to 0 rpm. S55. Set the servo motor's adjustment speed based on the pressure acquisition value; when 0 < pressure acquisition value ≤ 10, set the servo motor's adjustment speed to 1000 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 10 < pressure acquisition value ≤ 20, set the servo motor's adjustment speed to 900 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 20 < pressure acquisition value ≤ 30, set the servo motor's adjustment speed to 800 rpm, perform PID parameter settings, and make the servo motor rotate forward; when 30 < pressure acquisition value ≤ 35, set the servo motor's adjustment speed to 7... 00rpm, set the PID parameters to make the servo motor rotate forward; when 35 < pressure acquisition value ≤ 40, set the servo motor adjustment speed to 600rpm, set the PID parameters to make the servo motor rotate forward; when 40 < pressure acquisition value ≤ 45, set the servo motor adjustment speed to 500rpm, set the PID parameters to make the servo motor rotate forward; when 45 < pressure acquisition value < 50, set the servo motor adjustment speed to 400rpm, set the PID parameters to make the servo motor rotate forward; when the pressure acquisition value ≥ 50, set the servo motor adjustment speed to 0rpm.

2. The working method as described in claim 1, characterized in that: PID parameters are optimized using the Ziegler-Nichols method; this involves the following steps: S511. Convert the current PID controller to proportional control mode, and adjust the integral gain K. i and differential gain K d Set to zero; S512, Gradually increase the proportional gain K p Until it exhibits continuous oscillation, at which point the proportional gain K... p That is, the critical gain K. u ; S513, at the proportional gain K p Reaching the critical gain K u At that time, record the oscillation period T. u ; S514, Using Critical Gain K u and oscillation period T u The PID parameters of the PID controller are calculated using the following formula: P control: K p =K u ; PI control: PID control: K p =0.6K u , Based on the analysis of the experimental data, the following conclusions were drawn: K u =20,T u =5s。 3. The emulsion pump loading valve speed control system operating according to the working method described in claim 1 or 2, characterized in that: An encoder is installed between the servo driver and the servo motor, and the servo motor is controlled by the signal from the encoder.

4. The emulsion pump loading valve speed control system as described in claim 3, characterized in that: A speed reduction mechanism and a coupling mechanism are provided between the servo motor and the emulsion pump loading valve. The servo motor is connected to the emulsion pump loading valve through the speed reduction mechanism and the coupling mechanism in sequence.

5. The emulsion pump loading valve speed control system as described in claim 4, characterized in that: The reduction mechanism is a planetary gear reducer.

6. The emulsion pump loading valve speed control system as described in claim 5, characterized in that: The coupling mechanism is one of the following: gear transmission mechanism, cam transmission mechanism, coupling transmission mechanism, and synchronous belt transmission mechanism.

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