Elevator operation and electrical parking control system and method based on multi-modal switching

Abstract

The application belongs to the technical field of mine equipment, and specifically discloses a hoist operation and electrical parking control system and method based on multi-modal switching, which performs modal judgment and division on the current operation state of the hoist, switches the variable structure speed regulator to a fast response structure at the start, simultaneously inputs a rotor position identification, a load observer module and the like to speed up the system response speed, and realizes rapid establishment of torque; at the acceleration and deceleration stages of the hoist, the variable structure speed regulator is switched to a conventional structure, and a rotational inertia torque compensation module is added to enhance the system anti-disturbance ability and improve the transmission performance; at the parking brake stage, the variable structure speed regulator is switched to a high-precision structure, and a position closed-loop control module is added to improve the parking accuracy and static stability; after hydraulic holding brake, the data lines of all modules are linearly cleared to realize smooth parking, so that the system high-precision, impact-free start and stop are realized according to different working conditions, and the optimal control of the whole hoisting and transportation cycle of the hoist is ensured.

Description

Technical Field

[0001] This invention belongs to the field of mining equipment technology, and specifically discloses a hoist operation and electrical parking control system and method based on multi-modal switching. Background Technology

[0002] As mineral resources enter the deep mining stage, the drive power of mine hoists also increases. Traditional high-speed asynchronous motors with reducers have low transmission efficiency, and their operating power is limited by the reducer, making them unsuitable for high-power hoist systems. To improve transmission efficiency, a low-speed direct-drive structure without a reducer is adopted, using an AC synchronous motor. Low-speed direct-drive synchronous hoists differ significantly from high-speed asynchronous hoists in their transmission characteristics. First, they have higher operating power, typically exceeding 3MW per unit. Second, due to the absence of a reducer, the operating speed and frequency are lower, requiring higher precision in low-speed control. Third, the system has a larger moment of inertia, resulting in greater start-stop shocks and higher requirements for dynamic torque response.

[0003] Hoists typically employ a pre-set torque scheme during the start-up and opening phase to prevent slippage, and a speed-operated brake-based parking scheme during the stopping phase to achieve precise, fixed-point stopping. This start-stop scheme exhibits minimal mechanical shock in small-to-medium power hoists, but its application in high-power, low-speed direct-drive hoists results in significant start-stop shock. During startup, the mismatch between the pre-set torque and the actual load torque causes fluctuations in startup speed, especially during the lowering of heavy loads, leading to substantial speed overshoot. During stopping, the creeping speed is approximately 5% of the rated speed, and forced braking causes significant mechanical shock. Furthermore, different operating states of the hoist require different transmission performance, necessitating the classification of hoist operating modes and the design of different control schemes for each mode. Finally, a combination of electric parking brake and hydraulic brake is employed to achieve shock-free start-stop. Summary of the Invention

[0004] To address the problems in the background art, this invention discloses a hoist operation and electric parking control system and method based on multi-mode switching. An electric parking controller is added between the hoist control system and the frequency conversion drive system to divide the hoist operation modes, design different control schemes under different operation modes, and use electric parking and hydraulic brake in combination to achieve shock-free start and stop.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0006] The hoist operation and electric parking control system based on multi-modal switching includes a hoist control system, a variable frequency drive system, and an electric parking controller located between the two. The electric parking controller includes a variable structure speed regulator module, a moment of inertia torque compensation module, a rotor position identification module, a load observer module, and a position closed-loop control module. The electric parking controller communicates with the hoist control system via digital and analog signals, and with the variable frequency drive system via fiber optic communication. The electric parking controller collects real-time data on the hoist cage position, brake status, and creep distance. The system extracts and integrates key information such as departure and speed commands to identify and classify the hoist's operating characteristics. It also performs modal judgment and classification of the hoist's current operating state. Based on the operating characteristics of different modes, it quantifies the mode switching variables λ1 to λ7. Among them, λ1 to λ4 are switching variables, responsible for switching the operation of different functional modules under each mode, while λ5 to λ7 are continuous variables, responsible for controlling the proportion of each part of the variable structure speed regulator. By adjusting the variables λ1 to λ7, the system can adopt different control schemes under different modes to ensure that the hoist operates in the optimal state at each stage of start-up, shutdown, and operation.

[0007] Furthermore, in the multi-modal switching-based hoist operation and electrical parking control system, λ1 controls the engagement and disengagement of the rotor position identification module; λ2 controls the engagement and disengagement of the moment of inertia torque compensation module; λ3 controls the engagement and disengagement of the load observer module; λ4 controls the engagement and disengagement of the position closed-loop control module; and λ5, λ6, and λ7 respectively control the weights of the proportional, integral, and derivative components in the variable structure speed regulator.

[0008] Furthermore, the control schemes for the hoist operation and electric parking control system based on multi-mode switching are as follows:

[0009] During the start-up and opening of the electrical parking brake, the rotor position identification and load observer modules are activated, and the expression for the variable structure speed regulator at this time is: In the formula, The speed regulator P adjustment coefficient, To add a P adjustment coefficient, For speed deviation, To control the maximum speed deviation, The integral control coefficient of the speed regulator. The differential adjustment coefficient of the speed regulator. Add an adjustment coefficient to the derivative of the speed regulator. This represents the change in speed deviation. This is the maximum control value for speed deviation variation;

[0010] During the normal transport phase, a traditional synchronous motor vector control scheme is used. In the acceleration / deceleration phase, a moment of inertia torque compensation module is implemented to improve speed tracking accuracy. The expression for moment of inertia torque is as follows: In the formula, To the moment of inertia of the hoist system, The acceleration or deceleration of the hoist is zero during uniform operation, and the additional torque automatically disengages.

[0011] During the crawling electric parking phase, a position closed-loop control module is added before the speed regulator to achieve precise stopping. The expression for the variable structure speed regulator at this time is: In the formula, Add an integral coefficient to the speed regulator;

[0012] After stopping and during the brake engagement phase, the closed-loop control module for the brake engagement position exits, and all modules of the system remain in their final operating state. At this time, the data of each module is linearly cleared to zero, thereby achieving a smooth stop of the hoist system.

[0013] The method for hoist operation and electric parking control based on multi-modal switching utilizes the aforementioned hoist operation and electric parking control system to achieve multi-modal switching of the hoist operation and electric parking control system, specifically including the following steps:

[0014] Step 1: Extraction of hoist operation characteristics: Collect hoist cage position, brake status, creep distance, and speed command information through the electrical parking controller, and extract the hoist operation characteristics such as operation stage, speed trend, braking time point, stopping point distance, and acceleration / deceleration change law.

[0015] Step 2: Perform integrated analysis and modal classification of the hoist's operating characteristics: Based on the hoist's operating characteristics, the hoist's operating cycle is divided into four operating modes: start-up with electric parking brake, hoisting, crawling with electric parking brake, and hydraulic brake after stopping;

[0016] Step 3: Position Closed-Loop Control Calculation and Frequency Setting: Before parking braking, the hoist control system provides the position control value. The electric parking controller performs position closed-loop calculation based on the position control value and outputs the frequency control additional value through the position closed-loop calculation. At this time, the inverter frequency setpoint is ,in, It is the command value given by the control system to the frequency converter, and the activation and deactivation of the λ4 control position closed-loop control module;

[0017] Step 4: Speed ​​Regulator Calculation: The output torque control value of the speed regulator is... ,in, , , Divide into different modes , , Perform quantitative calculations;

[0018] Step 5: Torque control value calculation: The load torque observation value is calculated by the load observer module. The moment of inertia torque is calculated based on the system's moment of inertia and acceleration / deceleration. The torque adjustment value is output by the speed regulator. The torque control value can be calculated. ,in and The input and exit are determined by and control;

[0019] Step Six: Synchronous Motor Rotor Position Calculation: Rotor position calculation includes rotor initial position identification and rotor position change value calculation. Rotor initial position identification uses excitation step response excitation to extract rotor initial position information from the stator induced voltage. Rotor initial position identification is only performed once before startup. Determine whether it is in operation; use an encoder to calculate the real-time position change of the rotor, then the expression for the real-time rotor position is: ,in This is the initial position of the rotor. The real-time change value of the rotor position calculated by the encoder;

[0020] Step 7: Mode switching calculation: Switch the control scheme under different operating modes;

[0021] Step 8: Control mode reconfiguration based on mode switching calculation results: After reconfiguration, the control mode is executed by the controller in the frequency converter and drives the motor. The speed command and feedback value are processed by the variable structure speed regulator to obtain the torque adjustment value. The torque adjustment value and other torque compensation values ​​are used to calculate the torque setpoint. At the same time, magnetic field orientation and active and reactive power decoupling calculations are performed based on the rotor position. Finally, the output voltage is adjusted by torque current and reactive current to drive the motor.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] This invention relates to a multi-modal switching hoist operation and electrical parking control system and method. An electrical parking controller is added between the hoist control system and the variable frequency drive system. Based on the variable frequency drive's operating status, control system commands, container position, and brake status, the electrical parking controller performs modal judgment and classification of the hoist's current operating state and implements a multi-modal control scheme. During startup, the variable structure speed regulator switches to a fast-response structure, and rotor position identification and load observer modules are activated to accelerate system response and achieve rapid torque establishment. During acceleration and deceleration, the variable structure speed regulator switches to a conventional structure, and a rotational inertia torque compensation module is added to enhance the system's anti-disturbance capability and improve transmission performance. During parking and braking, the variable structure speed regulator switches to a high-precision structure, and a position closed-loop control module is added to improve parking accuracy and static stability. After hydraulic braking, the data from each module is linearly cleared to achieve smooth parking. Thus, multi-modal switching according to different operating conditions enables high-precision, shock-free start-stop of the system, ensuring optimal control of the hoist throughout its entire lifting cycle. Attached Figure Description

[0024] Figure 1 This is a block diagram of the hoist operation and electrical parking control system based on multi-modal switching of the present invention;

[0025] Figure 2 This is a block diagram of the control scheme for the start-up and opening of the electrical parking brake in this invention;

[0026] Figure 3 This is a block diagram of the control scheme for the crawling electric parking stage in this invention. Detailed Implementation

[0027] To better understand the present invention, the following embodiments further illustrate the content of the invention, but the scope of protection of the present invention is not limited to the following embodiments. Numerous specific details are set forth in the following description to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details.

[0028] Combined with appendix Figures 1-3 This paper details the hoist operation and electrical parking control method based on multi-modal switching of the present invention, with the specific steps as follows:

[0029] Step 1: Extraction of hoist operating features, such as Figure 1As shown, a dedicated electrical parking controller is added between the hoist control system and the frequency converter. This controller uses a DSP28335 controller and communicates with the hoist control system in both digital and analog quantities, and with the frequency converter drive system in fiber optic communication. The electrical parking controller includes a variable structure speed regulator module, a moment of inertia torque compensation module, a rotor position identification module, a load observer module, and a position closed-loop control module. The electrical parking controller collects information such as the hoist cage position, brake status, creep distance, and speed command, and extracts features such as the hoist operation stage, speed trend, braking time point, stopping point distance, and acceleration / deceleration variation law.

[0030] Step Two: Perform integrated analysis and modal classification of the operating characteristics. The hoist's operating modes are divided into four types: start-up with electric parking, lifting, crawling with electric parking, and hydraulic brake after stopping. Analyze the characteristics of each operating mode. Start-up with electric parking requires a rapid torque response to establish torque balance at the moment of opening the gate. The lifting mode is divided into three stages: acceleration, constant speed, and deceleration. The acceleration and deceleration stages require overcoming the moment of inertia torque, requiring the system to have rapid speed tracking capability. The crawling with electric parking stage requires high-precision speed and position control. The hydraulic brake after stopping requires the electric drive system to smoothly disengage.

[0031] The electric parking controller outputs seven adjustment variables λ1, λ2, λ3, λ4, λ5, λ6, and λ7. λ1 controls the engagement and disengagement of the rotor position identification module; λ2 controls the engagement and disengagement of the moment of inertia torque compensation module; λ3 controls the engagement and disengagement of the load observer module; λ4 controls the engagement and disengagement of the position closed-loop control module; and λ5, λ6, and λ7 control the weights of the proportional, integral, and derivative functions in the variable structure speed regulator. The values ​​of the adjustment variables under each mode are shown in Table 1. The adjustment variables are calculated by the electric parking controller based on the current operating status of the hoist, and the engagement and disengagement of the corresponding functional modules under different modes are achieved through changes in the data from λ1 to λ7.

[0032] Table 1. Modal Switching Variable Data Table

[0033] Control schemes for each mode:

[0034] During the start-up and opening of the electrical parking phase, a high dynamic response control mode for motor torque is formed by the rotor position identification module, the variable structure speed regulator module, and the load observer module. This allows for the rapid establishment of a torque that matches the load after the brake is opened. The rotor position identification and load observer modules are engaged, and at this time, the expression for the variable structure speed regulator is: In the formula, The speed regulator P adjustment coefficient, To add a P adjustment coefficient, For speed deviation, To control the maximum speed deviation, The integral control coefficient of the speed regulator. The differential adjustment coefficient of the speed regulator. Add an adjustment coefficient to the derivative of the speed regulator. This represents the change in speed deviation. The maximum control value for speed deviation variation is shown in the block diagram of the specific control scheme. Figure 2 As shown;

[0035] During the lifting operation, the variable structure speed regulator module reverts to conventional PI speed regulation, improving the system's anti-disturbance capability. Simultaneously, a rotational inertia torque compensation module is activated during acceleration / deceleration to enhance speed tracking accuracy. In the normal lifting phase, a traditional synchronous motor vector control scheme is used. During acceleration / deceleration, the rotational inertia torque compensation module is activated to improve speed tracking accuracy. The expression for rotational inertia torque is as follows: In the formula, To the moment of inertia of the hoist system, The acceleration or deceleration of the hoist is zero during uniform operation, and the additional torque automatically disengages.

[0036] During the crawling electric parking phase, a position closed-loop control module is added. Simultaneously, the P-regulation in the variable structure speed regulator module is reduced, while the I-regulation is enhanced to improve parking accuracy and stability. During the crawling electric parking phase, a position closed-loop control module is added before the speed regulator to achieve precise parking. The expression for the variable structure speed regulator at this time is: In the formula, The integral coefficient is added to the speed regulator. The specific control scheme block diagram is as follows: Figure 3 As shown;

[0037] During the braking phase after stopping, the closed-loop control module for the post-brake position exits, and all modules of the system remain in their final operating state. At this time, the data of each module is linearly cleared to achieve a smooth stop of the hoist system.

[0038] Step 3: Position Closed-Loop Control Calculation and Frequency Setting. Before parking braking, the hoist control system provides the position control value. The electric parking controller performs position closed-loop calculation based on the position control value, and outputs the frequency control additional value. At this time, the inverter frequency setpoint is ,in The λ4 control position closed-loop control module is activated and deactivated to provide the command value from the control system to the frequency converter.

[0039] Step 4: Speed ​​regulator calculation, the speed regulator output torque control value is ,in, ; ; Based on different modes, λ is divided 5、 λ 6、 λ7 is used for quantization calculation;

[0040] Step 5: Torque control value calculation. The load torque observation value is calculated by the load observer. The moment of inertia torque is calculated based on the system's moment of inertia and acceleration / deceleration. The torque adjustment value is output by the speed regulator. The torque control value can be calculated. ,in and The input and exit are determined by and control.

[0041] Step Six: Synchronous Motor Rotor Position Calculation. Rotor position calculation includes initial rotor position identification and calculation of rotor position change values. Initial rotor position identification uses excitation step response to extract initial rotor position information from the stator induced voltage. This initial rotor position identification is performed only once before startup. Determine whether it is in operation; use an encoder to calculate the real-time position change value, then the expression for the rotor's real-time position is: ,in This is the initial rotor position. The real-time change value of the rotor position calculated by the encoder.

[0042] Step 7: Mode switching calculation. Switch the control scheme according to Table 1 under different operating modes.

[0043] Step 8: Based on the mode switching calculation results, the control mode is recombined. After recombination, the control mode is executed by the controller in the frequency converter to drive the motor. The speed command and feedback value are processed by the variable structure speed regulator to obtain the torque adjustment value. The torque adjustment value, together with other torque compensation values, is used to calculate the torque setpoint. At the same time, field orientation and active and reactive power decoupling calculations are performed based on the rotor position. Finally, the output voltage is adjusted by torque current and reactive current to drive the motor.

[0044] This invention addresses the problems of large mechanical impact during start-up and shutdown and multiple operating condition switching in traditional variable frequency drive systems for hoists. It adopts a combination of electric parking brake and hydraulic brake. When starting, the brake is first opened, the hoist is parked at 0 speed, and then it starts running according to the speed command. When stopping, the electric parking brake is first opened at 0 speed, and then the mechanical brake is applied, so as to achieve high-precision and shock-free start-up and shutdown of the system.

Claims

1. A hoist operation and electrical parking control system based on multi-modal switching, characterized in that, The system includes a hoist control system, a variable frequency drive system, and an electrical parking controller located between the two. The electrical parking controller includes a variable structure speed regulator module, a moment of inertia torque compensation module, a rotor position identification module, a load observer module, and a position closed-loop control module. The electrical parking controller communicates with the hoist control system via digital and analog signals, and with the variable frequency drive system via fiber optic communication. The electrical parking controller collects key information such as the hoist cage position, brake status, creep distance, and speed command in real time, extracts and integrates the hoist's operating characteristics, and performs modal judgment and classification of the hoist's current operating state. Based on the different modal operating characteristics, the modal switching variables λ1 to λ7 are quantified. Among them, λ1 to λ4 are switching variables, responsible for switching the operation of different functional modules under each mode, and λ5 to λ7 are continuous variables, responsible for controlling the proportion of each part of the variable structure speed regulator. By adjusting the variables λ1 to λ7, the system can adopt different control schemes under different modes, ensuring that the hoist operates in an optimal state at each stage of start-up, shutdown, and operation.

2. The hoist operation and electrical parking control system based on multi-mode switching according to claim 1, characterized in that, λ1 controls the activation and deactivation of the rotor position identification module; λ2 controls the activation and deactivation of the moment of inertia torque compensation module; λ3 controls the activation and deactivation of the load observer module; λ4 controls the activation and deactivation of the position closed-loop control module; λ5, λ6, and λ7 respectively control the weights of the proportional, integral, and derivative functions in the variable structure speed regulator.

3. The hoist operation and electrical parking control system based on multi-mode switching according to claim 2, characterized in that, Control schemes for each mode: During the start-up and opening of the electrical parking brake, the rotor position identification and load observer modules are activated, and the expression for the variable structure speed regulator at this time is: In the formula, The speed regulator P adjustment coefficient, To add a P adjustment coefficient, For speed deviation, To control the maximum speed deviation, The integral control coefficient of the speed regulator. The differential adjustment coefficient of the speed regulator. Add an adjustment coefficient to the derivative of the speed regulator. This represents the change in speed deviation. This is the maximum control value for speed deviation variation; During the normal transport phase, a traditional synchronous motor vector control scheme is used. In the acceleration / deceleration phase, a moment of inertia torque compensation module is implemented to improve speed tracking accuracy. The expression for moment of inertia torque is as follows: In the formula, To the moment of inertia of the hoist system, The acceleration or deceleration of the hoist is zero during uniform operation, and the additional torque automatically disengages. During the crawling electric parking phase, a position closed-loop control module is added before the speed regulator to achieve precise stopping. The expression for the variable structure speed regulator at this time is: In the formula, Add an integral coefficient to the speed regulator; After stopping and during the brake engagement phase, the closed-loop control module for the brake engagement position exits, and all modules of the system remain in their final operating state. At this time, the data of each module is linearly cleared to zero, thereby achieving a smooth stop of the hoist system.

4. A hoist operation and electrical parking control method based on multi-modal switching, characterized in that, The multi-mode switching of the hoist operation and electric parking control system based on multi-mode switching as described in claim 3 is achieved by the following steps: Step 1: Extraction of hoist operating characteristics: Collect hoist cage position, brake status, creep distance, and speed command information through the electrical parking controller to extract the hoist operating characteristics; Step 2: Perform integrated analysis and modal classification of the hoist's operating characteristics: Based on the hoist's operating characteristics, the hoist's operating cycle is divided into four operating modes: start-up with electric parking brake, hoisting, crawling with electric parking brake, and hydraulic brake after stopping; Step 3: Position Closed-Loop Control Calculation and Frequency Setting: Before parking braking, the hoist control system provides the position control value. The electric parking controller performs position closed-loop calculation based on the position control value and outputs the frequency control additional value through the position closed-loop calculation. At this time, the inverter frequency setpoint is ,in, It is the command value given to the frequency converter by the control system. Activation and deactivation of the position closed-loop control module; Step 4: Speed ​​Regulator Calculation: The output torque control value of the speed regulator is... ,in, , , Divide into different modes , , Perform quantitative calculations; Step 5: Torque control value calculation: The load torque observation value is calculated by the load observer module. The moment of inertia torque is calculated based on the system's moment of inertia and acceleration / deceleration. The torque adjustment value is output by the speed regulator. The torque control value can be calculated. ,in and The input and exit are determined by and control; Step Six: Synchronous Motor Rotor Position Calculation: Rotor position calculation includes rotor initial position identification and rotor position change value calculation. Rotor initial position identification uses excitation step response excitation to extract rotor initial position information from the stator induced voltage. Rotor initial position identification is only performed once before startup. Determine whether it is in operation; use an encoder to calculate the real-time position change of the rotor, then the expression for the real-time rotor position is: ,in This is the initial position of the rotor. The real-time change value of the rotor position calculated by the encoder; Step 7: Mode switching calculation: Switch the control scheme under different operating modes; Step 8: Control mode reconfiguration based on mode switching calculation results: After reconfiguration, the control mode is executed by the controller in the frequency converter and drives the motor. The speed command and feedback value are processed by the variable structure speed regulator to obtain the torque adjustment value. The torque adjustment value and other torque compensation values ​​are used to calculate the torque setpoint. At the same time, magnetic field orientation and active and reactive power decoupling calculations are performed based on the rotor position. Finally, the output voltage is adjusted by torque current and reactive current to drive the motor.

5. The hoist operation and electrical parking control method based on multi-mode switching according to claim 4, characterized in that, In step one, the operating characteristics of the hoist include the operating stage, speed trend, braking time point, distance to the stopping point, and acceleration / deceleration variation law.

Images