Device, control method and parameter setting method of switchgear motor operating mechanism

Abstract

The invention discloses a switch equipment motor operating mechanism device, a control method and a parameter setting method. The switch equipment motor operating mechanism comprises a motor, a transmission mechanism, a controller, an inversion unit, a driving unit, a detection unit, a power supply circuit and an upper computer. The controller is a DSP processor, processes data collected by the detection unit, executes a three-ring PI control algorithm, and outputs a PWM signal to the driving unit. The driving unit controls the inversion unit, and the inversion unit converts direct current of the power supply circuit into three-phase alternating current to drive a motor; the upper computer is in communication connection with the controller, monitors the state of the motor in real time, adjusts control parameters and displays real-time data. Through the three-ring control algorithm and the particle swarm optimization, the control precision, the intelligent level and the debugging efficiency of the high-voltage circuit breaker operating mechanism are remarkably improved, the workload of debugging personnel is effectively reduced, and the problems of insufficient dynamic adjustment, parameter solidification, manual dependence and the like in the prior art are solved.

Description

Technical Field

[0001] The present invention relates to a switching device in a power system, and particularly to a device, a control method, and a parameter setting method for a motor operating mechanism of a switching device. Background Art

[0002] With the development of smart grid technology, the power system has higher and higher requirements for the stability, reliability, and intelligence of high-voltage switching devices. Among them, high-voltage three-position switches and circuit breakers are important switching devices in the power system, which play the functions of protecting and controlling circuits.

[0003] The opening and closing operations of the switching device are completed by the operating mechanism driving the moving contact. The transmission mechanism of the motor operating mechanism is simple, and the controllability of the motor is relatively strong. It can move according to the set motion curve through the control algorithm, reduce the collision force of the contact, and increase the mechanical life of the switching device.

[0004] The invention with the application number CN201710817179.3 discloses a control system and a control method for a motor operating mechanism of a high-voltage circuit breaker. The control system for the motor operating mechanism of the high-voltage circuit breaker of this invention includes an energy storage capacitor module, an IGBT module, a detection circuit module, an isolation drive module, a control circuit module, and a monitoring module; the control method for the motor operating mechanism of the high-voltage circuit breaker of this invention divides the control of the motor into three stages, including a starting stage, a constant speed stage, and a buffering stage, and realizes segmented control by modifying the displacement given value in different stages. The control system and the control method for the motor operating mechanism of the high-voltage circuit breaker of this invention adopt a segmented control logic (starting / constant speed / buffering stage), rely on simple displacement given adjustment, cannot track the motor motion state in real time, resulting in insufficient control accuracy, large contact collision force, and short mechanical life. The parameter adjustment of this invention depends on manual experience, there are many parameters of the motor controller, and it takes a lot of time for manual debugging of parameters, with low debugging efficiency and limited accuracy. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a device for a motor operating mechanism of a switching device with good control accuracy and fast response speed.

[0006] Another technical problem to be solved by the present invention is to provide a control method for a motor operating mechanism of a switching device with good control accuracy and fast response speed.

[0007] Another technical problem to be solved by the present invention is to provide a parameter setting method with high debugging efficiency and capable of improving the control accuracy of a motor operating mechanism of a switching device.

[0008] To solve the above technical problems, the technical solution adopted by the present invention is a device for a motor operating mechanism of a switching device, comprising a motor, a transmission mechanism, a controller, an inverter unit, a drive unit, a detection unit, a power supply circuit and a host computer; The motor is a permanent magnet synchronous motor, and its rotor main shaft is connected to the transmission mechanism. When the motor rotates, it drives the transmission mechanism to move, and the transmission mechanism pushes the moving end of the switching device to realize opening and closing actions; The controller is a DSP processor, which processes the data collected by the detection unit, executes a three-loop PI control algorithm, and outputs a PWM signal to the drive unit; The inverter unit converts the direct current of the power supply circuit into three-phase alternating current to drive the motor; The drive unit controls the inverter unit; The detection unit collects the current, position and rotation angle signals of the motor; The host computer is communicatively connected to the controller, monitors the motor state in real time, adjusts the control parameters, and displays the real-time data; The power supply circuit supplies power to the controller, the drive unit and the detection unit.

[0009] The above-mentioned device for the motor operating mechanism of the switching device includes a communication unit. The power supply circuit includes a rectification unit, an energy storage capacitor and a power supply unit. The power supply unit includes a low-voltage DC power supply and an AC power supply. The low-voltage DC power supply supplies power to the controller, the drive unit and the detection unit. The AC power supply is converted into direct current through the rectification unit to charge the energy storage capacitor; the inverter unit adopts a three-phase bridge inverter circuit, and each bridge arm includes an IGBT and a buffer circuit; the detection unit includes a current sensor, a position sensor, an encoder and a signal processing circuit. The current sensor is installed in the three-phase coils of the permanent magnet synchronous motor to detect the three-phase current of the permanent magnet synchronous motor; the position sensor is installed at the moving contact position of the switching device to detect the displacement of the moving contact; the encoder detects the mechanical rotation angle of the motor, and the signal processing circuit limits the output voltage of the sensor and the encoder to the acceptance voltage range of the controller; the host computer displays the settings of the current motor displacement, speed and stroke curve through a human-machine interface, and establishes communication with the controller through the communication unit. The host computer sends instructions to the controller to control the rotation of the motor; the controller transmits sampling data, motor parameters and controller parameters to the host computer. The host computer optimizes the obtained data and the set stroke data to obtain an optimized trajectory and PI parameters, and transmits the optimized trajectory and PI parameters to the controller; the communication unit establishes communication between the controller and the host computer.

[0010] A control method for the above-mentioned motor operating mechanism of the switching device includes the following steps: 301) Obtain a preset optimal speed curve and PI parameters; 302) Collect the three-phase current values, rotor position, and speed signals of the permanent magnet synchronous motor; 303) The processor calculates the d-axis and q-axis control voltages according to the collected data through the PI three-loop control algorithm, and generates PWM signals through coordinate transformation and SVPWM algorithm; in the PI three-loop control algorithm, the position loop is P control, and the speed loop and current loop are PI control; 304) Control the inverter unit through the drive unit to drive the permanent magnet synchronous motor to move according to the set curve.

[0011] The control method of the motor operating mechanism of the switchgear described above, Step 303 includes the following steps: 401) Angle loop control: Obtain the preset target angle of the motor and the actual angle collected by the detection unit, and calculate the angle deviation; adjust the angle deviation through the position loop P controller to output the reference speed; 402) Speed loop control: Obtain the reference speed and the actual rotor speed collected by the detection unit, and calculate the speed deviation; adjust the speed deviation through the speed loop PI controller to output the reference d-axis current and reference q-axis current; 403) Current loop control: Collect the three-phase current, and convert it into the d-axis current and q-axis current in the rotating coordinate system through Clark transformation and Park transformation; calculate the d-axis and q-axis current deviations, and generate the reference d-axis voltage and reference q-axis voltage through the current loop PI controller; 404) Voltage transformation and PWM generation: Convert the reference d-axis voltage and reference q-axis voltage into the α-axis and β-axis voltages in the stationary coordinate system through Park inverse transformation; use the space vector pulse width modulation (SVPWM) algorithm to generate 6-way PWM signals; In the motor drive control of step 304, the inverter unit is controlled through the 6-way PWM signals to drive the permanent magnet synchronous motor to move according to the set trajectory.

[0012] For the control method of the motor operating mechanism of the switchgear described above, the control increment of the position loop P controller is:

[0013] Wherein, is the control increment of the position loop P controller in the current control cycle, is the position deviation in the current control cycle, is the position deviation in the previous control cycle, is the proportional coefficient difference of the position loop P controller.

[0014] For the control method of the motor operating mechanism of the switchgear described above, the control increment of the speed loop PI controller is:

[0015] Among them, is the control increment of the speed-loop PI controller in the current control cycle, is the speed deviation in the current control cycle, is the speed deviation in the previous control cycle, is the proportional coefficient of the speed-loop PI controller, is the integral coefficient of the speed-loop PI controller.

[0016] For the control method of the motor operating mechanism of the switchgear described above, the control increment of the current-loop PI controller is:

[0017] Among them, is the control increment of the current-loop P controller in the current control cycle, is the current deviation in the current control cycle, is the current deviation in the previous control cycle, is the proportional coefficient of the current-loop P controller, is the integral coefficient of the current-loop PI controller.

[0018] A parameter tuning method for the motor operating mechanism of the switchgear described above includes the following steps: 801) Motor operation control: Select the manual or automatic operation mode through the upper computer interface, and control the motor to run at a low speed; Monitor the motor current in real time, and stop running when the blocked-rotor state is detected, and record the starting position and the ending position; 802) Stroke setting: Configure the stroke parameters on the upper computer interface, including the stroke name, type, stage, time, starting position, and ending position; 803) Parameter optimization: Based on the motor operation data uploaded by the controller, generate the optimal stroke curve and the corresponding PI parameters through the particle swarm algorithm; 804) Stroke curve execution: Bind the optimal stroke curve to the input port, and execute the curve when the motor position is consistent with the curve starting point.

[0019] For the parameter tuning method of the motor operating mechanism of the switchgear described above, 901) In step 801, in the manual mode, control the motor to run by continuously triggering the jog button; In the automatic mode, start the motor by clicking the continuous operation button and stop automatically when blocked-rotor occurs; The determination condition for the blocked-rotor state is that the motor current exceeds 150% of the rated current continuously for 500 ms; The setting range of the low speed is 0 - 100 rpm; 902) In step 804, set the input port of the travel curve through the interface of the host computer, control the input port to execute the corresponding travel curve. When the position of the motor to be controlled is not at the starting point of the travel curve, this action cannot be executed, and a warning is issued on the host computer interface.

[0020] For the above-mentioned method for parameter setting of the motor operating mechanism of the switchgear, in step 803, the steps of parameter optimization include: 1001) Construct a motor dynamic equation through least squares fitting, including moment of inertia, damping coefficient, and torque parameters; 1002) Use the particle swarm optimization algorithm for multi-objective optimization, and the objective function is:

[0021] In the formula, is the absolute value of the error of the motor position, is the absolute value of the error of the motor speed, is the absolute value of the error of the motor current; 1003) Generate an optimal travel curve under the constraint conditions that the peak current ≤ 3 times the rated value and the total travel time ≤ the set threshold.

[0022] Through the three-loop control algorithm and particle swarm optimization, the present invention significantly improves the control accuracy, intelligent level, and debugging efficiency of the operating mechanism of the high-voltage circuit breaker, effectively reduces the workload of debugging personnel, and solves the problems of insufficient dynamic regulation, parameter solidification, and manual dependence existing in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0024] Figure 1 is the system structure block diagram of the motor operating mechanism of the switchgear in the embodiment of the present invention; Figure 2 is the control method principle block diagram of the motor operating mechanism of the switchgear in the embodiment of the present invention; Figure 3 is the flowchart of the debugging method of the motor operating mechanism of the switchgear in the embodiment of the present invention; Figure 4 is the flowchart of the online parameter setting method of the motor operating mechanism of the switchgear in the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The motor operating mechanism of the switchgear in the embodiment of the present invention is as Figure 1 shown, and includes a permanent magnet synchronous motor, a transmission mechanism, a DSP controller, an inverter unit, a drive unit, a detection unit, a communication unit, and a power supply circuit. The power supply circuit includes a rectification unit, an energy storage capacitor, and a power supply unit.

[0026] The input of the power supply unit is the mains AC220V, and the outputs are DC15V, DC12V and DC3.3V. The output terminals of the power supply unit are correspondingly connected to the power supply ports of the drive unit, the detection unit and the controller, and supply power to the drive unit, the detection unit and the controller respectively.

[0027] The input of the rectification unit is the mains AC220V, and the output voltage is an adjustable DC voltage. The rectification unit uses a rectifier bridge structure, which contains 4 diodes to convert the mains 220V into direct current; the energy storage capacitor is connected to the output terminal of the rectification unit and the input terminal of the inversion unit. The output terminal of the energy storage capacitor is connected to the inversion unit.

[0028] The inversion unit consists of a three-phase bridge IGBT inversion circuit. Each bridge arm has a resistor-capacitor buffer circuit, which is used to suppress the change rate of the IGBT voltage and current, reduce the damage of the spike voltage to the IGBT, and absorb the residual charge of the capacitor. The selection of the IGBT, resistor and capacitor is determined by the parameters of the motor; the drive unit is selected according to the parameters of the IGBT of the inversion unit to control the conduction of the IGBT.

[0029] The input terminal of the inversion unit is the energy storage capacitor, the control terminal is the output of the drive unit, and the output terminal is connected to the permanent magnet synchronous motor. The input terminal of the drive unit is the PWM output port of the controller, and the output terminal is connected to the control terminal of the inversion unit.

[0030] The rotor spindle of the permanent magnet synchronous motor is connected to the transmission mechanism. When the motor rotates, it drives the transmission mechanism to move, and the transmission mechanism pushes the moving end of the switching device to realize the opening and closing actions. The parameters of the permanent magnet synchronous motor should meet the switching action index, and the motor power, speed and torque are determined according to the switching action speed. The input terminal of the permanent magnet synchronous motor is connected to the output terminal of the inversion unit, the motor is connected to the transmission mechanism, and kinetic energy is provided to the moving end of the switch to make the moving end of the switch complete the action.

[0031] The detection unit detects the position of the moving end of the switch, the motor speed, the rotation angle and the current. The detection unit includes a current sensor, a position sensor, an encoder and a signal processing circuit. The input terminal of the signal processing circuit is connected to the current sensor, the position sensor and the optical encoder, and the output terminal is connected to the controller (DSP). The signal processing circuit limits the output voltage of the sensor and the encoder to the acceptable voltage range of the controller. After the collected data is processed by the signal processing, it is transmitted to the DSP controller. The current sensor is installed in the three-phase coil of the permanent magnet synchronous motor to detect the three-phase current of the permanent magnet synchronous motor; the position sensor is installed at the moving contact position of the switching device to detect the displacement of the moving contact; the encoder detects the mechanical rotation angle of the motor, and the signal processing circuit limits the output voltage of the sensor and the encoder to the acceptable voltage range of the controller.

[0032] The model of the DSP controller is TMS320F28335. The DSP controller receives and processes the acquisition data of the detection unit, performs the three-loop PI control algorithm, transmits the PWM waveform obtained by the algorithm to the drive unit to complete the rotational motion control of the motor, and transmits the data to the upper computer through the communication unit.

[0033] The communication unit is the communication bridge between the upper computer and the controller. It uses the RS485 communication interface and the IEC61850 communication protocol to upload and download data.

[0034] The upper computer displays the settings of the current motor displacement, speed, and stroke curve through the human-machine interaction interface, establishes communication with the controller through the communication unit, sends instructions to the DSP controller to control the motor rotation; the DSP controller transmits the sampling data, motor parameters, and controller parameters to the upper computer. The upper computer optimizes the obtained data and the set stroke data to obtain the optimized trajectory and PI parameters, and transmits the optimized trajectory and PI parameters to the controller.

[0035] When the motor operating mechanism of the switchgear in the embodiment of the present invention works, the three-loop control algorithm (position loop P control, speed loop PI control, and current loop PI control) is executed by the DSP controller. First, the three-phase current of the motor, the rotor position, and the speed signal are collected. After Clark and Park coordinate transformations, the actual value is compared with the set value to obtain the deviation, and the control quantity is calculated through the incremental control algorithm. Then, after the Park inverse transformation and SVPWM modulation, 6-way PWM signals are generated to drive the IGBT inverter unit to output three-phase alternating current, so that the permanent magnet synchronous motor operates according to the set trajectory, thereby driving the transmission mechanism to accurately control the opening and closing actions of the switch moving contact.

[0036] The advantages of the motor operating mechanism of the switchgear in the embodiment of the present invention are as follows: 1) The DSP controller adopts the three-loop closed-loop control combined with the coordinate transformation algorithm, which can significantly improve the control accuracy and dynamic response speed; 2) The integrated communication unit supports the IEC61850 protocol, realizing the standardized interconnection with the smart grid; 3) The upper computer can monitor and optimize the parameters in real time, greatly improving the debugging efficiency and the system intelligence level.

[0037] The principle of the control method of the motor operating mechanism in the embodiment of the present invention is as Figure 2 shown, and the following steps are executed: Parameter acquisition and signal acquisition: Obtain the optimal speed curve and PI parameters of the current working condition; collect the three-phase output current of the current sensor processed by the signal processing unit, obtain the signal output by the photoelectric encoder, and obtain the position and speed of the rotor after being processed by the DSP processor.

[0038] Three-loop control operation: The DSP processor calculates the deviation between the motor rotation angle, angular velocity, three-phase current and the set motor rotation angle, calculated angular velocity and three-phase current, and uses the PI three-loop control algorithm to control the motor rotation angle, thereby controlling the movement of the transmission mechanism and the moving end of the switch. Among them, the position loop uses the P control algorithm, and the speed loop and current loop use the PI control algorithm.

[0039] 1) Position loop control (P control): The position loop calculates an ideal speed set value (output reference speed) based on the deviation (position error) between the actual angle of the motor rotor and the target angle.

[0040] Compare the preset angle with the actual angle collected by the detection unit to obtain the angle deviation, and calculate the control increment through the incremental position loop P controller:

[0041] In the formula, is the control increment of the position loop P controller in the current control cycle, is the position deviation in the current control cycle, is the position deviation in the previous control cycle, is the proportional coefficient of the position loop P controller.

[0042] 2) Speed loop control (PI control): The speed loop calculates the current set value of the motor in the rotating coordinate system (dq axis) based on the deviation (speed error) between the reference speed (from the position loop) and the actual rotational speed, and outputs the reference d-axis current and q-axis current.

[0043] Make a deviation between the reference speed and the detected rotor speed to obtain the speed error, and calculate the control increment through the incremental speed loop PI controller:

[0044] In the formula, is the control increment of the speed loop PI controller in the current control cycle, is the speed deviation in the current control cycle, is the speed deviation in the previous control cycle, is the proportional coefficient of the speed loop PI controller, is the integral coefficient of the speed loop PI controller.

[0045] 3) Current loop control (PI control): The current loop calculates the voltage set value required by the motor based on the deviation between the reference current (from the speed loop) and the actual current (obtained through Clark / Park transformation), and outputs the reference d-axis voltage and q-axis voltage for generating the PWM signal.

[0046] The three-phase current is converted into α-axis and β-axis currents through Clark transformation, and the α-axis and β-axis currents are converted into d-axis and q-axis currents through Park transformation; the d-axis and q-axis reference currents output by the speed loop are subtracted from the measured d-axis and q-axis currents to obtain the current error.

[0047] The control increment is calculated through an incremental current-loop PI controller:

[0048] In the formula, is the control increment of the current-loop P controller in the current control period, is the current deviation in the current control period, is the current deviation in the previous control period, is the proportional coefficient of the current-loop P controller, is the integral coefficient of the current-loop PI controller.

[0049] Coordinate transformation and PWM generation: The reference d-axis and q-axis voltages are transformed inversely through Park transformation to obtain α-axis and β-axis voltages, and the SVPWM algorithm is applied to convert the α-axis and β-axis voltages into 6-channel PWM signals.

[0050] Motor drive control: The 6-channel PWM signals are output to the drive unit, and the conduction of the IGBTs in the inverter unit is controlled through the drive unit; the energy storage capacitor discharges to drive the permanent magnet synchronous motor to rotate, driving the transmission mechanism to make the moving contact move along the set trajectory.

[0051] Control quantity update: The final control quantity in each control period consists of the control quantity in the previous period and the control increment in the current period:

[0052] In the formula, is the control quantity in the current control period, is the control quantity in the previous control period, (k) is the control increment in the current control period.

[0053] The parameters (K_pp, K_ps, K_is, K_pc, K_ic) of each control loop can be optimized through the parameter tuning system.

[0054] When it is detected that the motor current exceeds 150% of the rated current continuously for 500 ms, it is determined to be in the locked-rotor state and the PWM signal output is stopped.

[0055] The control method of the motor operating mechanism of the above switchgear realizes the precise control of the motor rotation angle, speed and current through the three-loop closed-loop control combined with coordinate transformation and SVPWM modulation, ensuring the stability and reliability of the movement of the moving contact of the switchgear.

[0056] The method for online tuning of the parameters of the motor operating mechanism of the present invention is as Figure 3 and Figure 4 shown. Through the collaborative work of the upper computer and the controller, the automatic optimization and debugging of the control parameters are realized, which specifically includes the following contents: The control method for manually operating the motor: By continuously clicking the jogging button on the upper computer interface, the motor rotates at a low speed. When the controller determines that the motor is in a stalled state, this operation ends, or by clicking the end operation button on the upper computer interface, this operation also ends, and the starting and ending positions of this operation are recorded. The control method for manually operating the motor includes the following steps: (1) Operation control step: The jogging button and the end operation button are set on the upper computer interface. When the operator continuously presses the jogging button on the upper computer interface, the controller sends a PWM speed regulation signal to the motor drive module, and the permanent magnet synchronous motor runs at a set low speed of 0 - 100 rpm. The controller monitors the three-phase current in real time (sampling rate 10 kHz).

[0057] (2) Stop control step: Automatic stop includes the following steps: When it is detected that the current value exceeds 150% of the rated current for 500 ms continuously, it is determined as a stalled state, and the PWM signal output is immediately stopped, and the stalled position (encoder value) is recorded.

[0058] Manual stop includes the following steps: The operator clicks the end operation button, and smooth deceleration is performed (deceleration rate 50 rpm / s²).

[0059] (3) Data storage step: Record the parameter values of the starting position (initial value of the optical encoder), the ending position (encoder value at stop), the peak current, and the running duration. Store them in the EEPROM of the controller for cyclic storage and synchronously upload them to the upper computer database.

[0060] The control method for automatically operating the motor: By clicking the automatic operation button on the upper computer interface, the motor rotates at a low speed. When the controller determines that the motor is in a stalled state, this operation ends, and the starting and ending positions of this operation are recorded. The control method for automatically operating the motor includes the following steps: (1) Operation control step: The host computer interface sets a continuous operation button. When the operator clicks the "Continuous Operation" button on the host computer, the controller sends a PWM speed regulation signal to the motor drive module, and the motor starts with a preset acceleration ramp and maintains a constant low speed of 0 - 100 rpm.

[0061] (2) Status monitoring steps: The controller continuously monitors and acquires the current values (A / B / C three - phase), speed values (rpm), and position encoder values (0.1° resolution) of the motor. Sampling period: current: 100 μs, position: 1 ms.

[0062] (3) Stalled rotation determination and handling steps as a protection mechanism: When the controller continuously monitors that the motor current > 150% of the rated value and lasts for 500 ms, it is determined to be in a stalled rotation state, and the PWM signal output is immediately stopped, and the starting position and ending position are output.

[0063] The control method for travel setting: includes adding a new travel on the host computer interface, modifying the travel name, type, stage, setting the travel time, starting and ending positions.

[0064] The travel configuration interface provided by the host computer includes: a travel name edit box (supporting ASCII character input), a travel type drop - down menu (including linear / curve / composite motion options), a stage selector (divided into stage I / II / III), time, position, and speed setting units.

[0065] The control method for parameter optimization: Select the travel type and stage on the host computer interface. According to the motor parameters uploaded by the controller, an optimal travel curve is adaptively optimized, and the optimal PI parameters are obtained based on this optimal curve. The control method for parameter optimization includes the following steps: (1) The host computer receives the real - time operation data set of the motor uploaded by the controller, including the phase current values, speed values, and position encoder values recorded in time series; based on the data set, a dynamic equation characterizing the mechanical characteristics of the motor is constructed by least - squares fitting, and the dynamic equation includes the correlation relationships of the moment of inertia, damping coefficient, and torque parameters.

[0066] (2) The particle swarm algorithm is used for multi - objective iterative optimization. Taking the minimum of the cumulative squared deviation between the actual position, speed, current of the motor and the preset target trajectory as the optimization goal, under the constraint conditions that the peak current does not exceed three times the rated value and the total travel time is less than the set threshold, an optimal travel curve that meets the dynamic performance requirements is generated.

[0067] (3) According to the characteristics of the optimized travel curve, combined with the preset system response time requirement and damping ratio value range, the proportional coefficient and integral coefficient of the proportional - integral controller are dynamically calculated to achieve the adaptive matching of the control parameters and the mechanical characteristics of the motor.

[0068] Among them, the objective function is:

[0069] In the formula, is the absolute value of the error of the motor position, is the absolute value of the error of the motor speed, is the absolute value of the error of the motor current.

[0070] After obtaining the PI parameter combination corresponding to the minimum value of the objective function J, write it into the register of the controller, and adjust the three-loop control algorithm in real time to make the actual motion trajectory of the motor optimally track the preset curve, and at the same time automatically adapt to the change of mechanical characteristics.

[0071] Control method for the motor stroke curve execution: Set the input port of the stroke curve on the upper computer interface, and execute the corresponding motor stroke curve by controlling the input port. When the motor position is not at the starting point of the stroke curve, the corresponding motor stroke curve cannot be executed, and a warning is issued on the upper computer interface.

[0072] The device, control method and parameter on-line tuning method of the switchgear motor operating mechanism provided by the present invention are convenient to debug, have high precision and small error, effectively reduce the workload of debuggers, and can complete precise control with the cooperation of sensors and control. According to the parameters and stroke settings of the motor, the optimal stroke curve is obtained, the collision of the contacts is reduced, and the general IEC61850 protocol is used in the communication protocol to provide a standardized communication protocol for the monitoring background, and the real-time state of the contact action can be displayed on-line.

Claims

1. A device for a switchgear motor operating mechanism, characterized in that: It includes a motor, a transmission mechanism, a controller, an inverter unit, a drive unit, a detection unit, a power supply circuit and a host computer; The motor is a permanent magnet synchronous motor, and its rotor main shaft is connected to the transmission mechanism. When the motor rotates, it drives the transmission mechanism to move, and the transmission mechanism pushes the moving end of the switch device to realize the opening and closing action; The controller is a DSP processor that processes the data collected by the detection unit, executes the three-loop PI control algorithm, and outputs a PWM signal to the drive unit; The inverter unit converts the DC power of the power circuit into three-phase AC power to drive the motor; The driving unit controls the inverter unit; The detection unit collects current, position and rotation angle signals of the motor; The host computer is connected to the controller for real-time monitoring of the motor status, adjustment of control parameters, and display of real-time data; The power supply circuit supplies power to the controller, the driving unit and the detection unit.

2. The device of the switchgear motor operating mechanism according to claim 1, characterized in that: It includes a communication unit, the power supply circuit includes a rectifier unit, an energy storage capacitor and a power supply unit, the power supply unit includes a low-voltage DC power supply and an AC power supply, wherein the low-voltage DC power supply supplies power to the controller, the drive unit and the detection unit, and the AC power supply is converted into DC power by the rectifier unit to charge the energy storage capacitor; the inverter unit adopts a three-phase bridge inverter circuit, and each bridge arm includes an IGBT and a buffer circuit; the detection unit includes a current sensor, a position sensor, an encoder and a signal processing circuit, the current sensor is installed in the three-phase coil of the permanent magnet synchronous motor to detect the three-phase current of the permanent magnet synchronous motor; the position sensor is installed at the moving contact position of the switch device to detect the moving contact The encoder detects the mechanical angle of the motor, and the signal processing circuit limits the output voltage of the sensor and the encoder to the acceptable voltage range of the controller; the host computer displays the current displacement, speed, and stroke curve settings of the motor through the human-computer interaction interface, and establishes communication with the controller through the communication unit. The host computer sends instructions to the controller to control the rotation of the motor; the controller transmits sampling data, motor parameters, and controller parameters to the host computer, and the host computer optimizes the obtained data and the set stroke data to obtain the optimized trajectory and PI parameters, and transmits the optimized trajectory and PI parameters to the controller; the communication unit establishes communication between the controller and the host computer.

3. A control method for a switchgear motor operating mechanism according to claim 1, characterized in that: The following steps are involved: 301) Obtaining the preset optimal speed curve and PI parameters; 302) Collect the three-phase current value, rotor position and speed signal of the permanent magnet synchronous motor; 303) The processor calculates the d-axis and q-axis control voltages through the PI three-loop control algorithm based on the collected data, and generates a PWM signal through coordinate transformation and SVPWM algorithm; in the PI three-loop control algorithm, the position loop is P control, and the speed loop and current loop are PI control; 304) The inverter unit is controlled by the drive unit to drive the permanent magnet synchronous motor to move according to the set curve.

4. The control method of the switchgear motor operating mechanism according to claim 3, characterized in that: Step 303 includes the following steps: 401) Angle loop control: obtain the preset motor target angle and the actual angle collected by the detection unit, calculate the angle deviation; adjust the angle deviation through the position loop P controller and output the reference speed; 402) Speed ​​loop control: obtain the reference speed and the actual rotor speed collected by the detection unit, calculate the speed deviation; adjust the speed deviation through the speed loop PI controller, and output the reference d-axis current and the reference q-axis current; 403) Current loop control: Collect three-phase currents and convert them into d-axis current and q-axis current in the rotating coordinate system through Clark transformation and Park transformation; calculate the d-axis and q-axis current deviations, and generate reference d-axis voltage and reference q-axis voltage through the current loop PI controller; 404) Voltage conversion and PWM generation: convert the reference d-axis voltage and the reference q-axis voltage into the α-axis and β-axis voltages in the stationary coordinate system through Park inverse transformation; use the space vector pulse width modulation (SVPWM) algorithm to generate 6-channel PWM signals; Step 304 is motor drive control, controlling the inverter unit through the six PWM signals to drive the permanent magnet synchronous motor to move along a set trajectory.

5. The control method of the switch device motor operating mechanism according to claim 3, characterized in that: The control increment of the position loop P controller is: ； in, is the control increment of the position loop P controller in the current control cycle, is the position deviation of the current control cycle, is the position deviation of the previous control cycle, is the proportional coefficient difference of the position loop P controller.

6. The control method of the switch device motor operating mechanism according to claim 3, characterized in that: The control increment of the speed loop PI controller is: ； in, is the control increment of the speed loop PI controller in the current control cycle, is the speed deviation of the current control cycle, is the speed deviation of the previous control cycle, is the proportional coefficient of the speed loop PI controller, It is the integral coefficient of the speed loop PI controller.

7. The control method of the switch device motor operating mechanism according to claim 3, characterized in that: The control increment of the current loop PI controller is: ； in, is the control increment of the current loop P controller in the current control cycle, is the current deviation of the current control cycle, is the current deviation of the previous control cycle, is the proportional coefficient of the current loop P controller, is the integral coefficient of the current loop PI controller.

8. A method for setting parameters of a switchgear motor operating mechanism according to claim 1, characterized in that: The following steps are involved: 801) Motor operation control: select manual or automatic operation mode through the host computer interface to control the motor to run at a low speed; monitor the motor current in real time, stop running when a stall state is detected, and record the starting and ending positions; 802) Trip setting: configure the trip parameters on the host computer interface, including trip name, type, stage, time, start position and end position; 803) Parameter optimization: Based on the motor operation data uploaded by the controller, the optimal travel curve and corresponding PI parameters are generated through the particle swarm algorithm; 804) Stroke curve execution: Bind the optimal stroke curve to the input port, and execute the curve when the motor position is consistent with the starting point of the curve.

9. The parameter setting method of the switchgear motor operating mechanism according to claim 8, characterized in that: 901) In step 801, in manual mode, the motor is controlled to run by continuously triggering the jog button; in automatic mode, the motor is started by clicking the continuous run button, and stops automatically when it is stalled; the stall state is determined by: the motor current exceeds 150% of the rated current for 500ms continuously; the low speed setting range is 0-100rpm; 902) In step 804, the input port of the stroke curve is set through the interface of the host computer, and the input port is controlled to execute the corresponding stroke curve. When the position of the controlled motor is not at the starting point of the stroke curve, the action cannot be executed and a warning is issued on the host computer interface.

10. The parameter setting method of the switchgear motor operating mechanism according to claim 8, characterized in that: In step 803, the parameter optimization step includes: 1001) Construct the motor dynamic equation by least squares fitting, including the moment of inertia, damping coefficient and torque parameters; 1002) Particle swarm algorithm is used for multi-objective optimization, and the objective function is: ； In the formula, is the absolute value of the motor position error, is the absolute value of the motor speed error, is the absolute value of the motor current error; 1003) Generate an optimal travel curve under the constraints of peak current ≤ 3 times the rated value and total travel time ≤ the set threshold.

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