Method for controlling a drive motor

Abstract

The invention relates to a method for controlling a drive motor. In the method for controlling a drive, in particular an electric drive, of an industrial device, a drive controller controls the drive motor, and the drive motor drives a mechanical device having one or more coupled components. The method is characterized in that the drive controller simulates the mechanical device of the device with the aid of a simulation model and pre-controls the drive motor based on the simulation.

Description

Technical Field

[0001] The invention relates to a method for controlling a drive motor, in particular an electric drive motor, of an industrial system, wherein a drive controller controls the drive motor and the drive motor drives a mechanical device of the system having one or more coupled components. Background Art

[0002] In industrial plants, electric drive motors are usually used, which drive various shafts of the plant. The shafts in turn drive components of the mechanical device, so that the plant performs its tasks during operation.

[0003] During operation of the device, correspondingly different rotational speeds and torques of the drive motor may be required. For example, different torques may be established in response to an acceleration of one of the components of the mechanical device or a temporarily occurring high friction. After such an event occurs, the drive controller reacts and, for example, adjusts the motor current or motor power accordingly. However, such an event may affect the synchronization and smooth running of the motor, whereby undesirable forces may occur in the mechanical device. Summary of the invention

[0004] The object of the present invention is to specify a method for controlling a drive motor which reduces or prevents the occurrence of synchronization disturbances and / or additional forces in the mechanical device.

[0005] The above technical problem is solved by the method according to the present invention.

[0006] In particular, the above technical problem is solved in that the drive controller simulates the mechanical device of the device by means of a simulation model and pre-controls the drive motor based on the simulation.

[0007] The invention is based on the knowledge that the movement of a mechanical device can be simulated in advance by means of a simulation model of the mechanical device. In the simulation, for example, an increased torque requirement can then be determined in advance. If such an increased torque requirement is detected, the drive motor can be pre-controlled so that this increased torque requirement does not have a negative impact on the smooth running of the motor or does not generate undesirable additional forces in the mechanical device, which, for example, increase the wear of the mechanical device.

[0008] In particular, the drive controller can perform precontrol with the aid of (theoretical) values ​​calculated in the simulation. Theoretically determined values ​​can be adjusted / improved by comparison with (real) values ​​actually measured on the device. In particular, trends can be determined by repeated comparison of theoretical values ​​with real values, which allow conclusions to be drawn about mechanical changes with respect to the service life of the industrial device. This allows models to be developed which make it possible to predict which mechanical components may be more susceptible to failure and / or wear in the future.

[0009] According to the invention, the simulation is performed by the drive controller itself (ie not by an external system), so that no additional components are required. Another advantage of performing the simulation in the drive controller itself is that the drive controller can directly further process the data obtained in the simulation and use it for pre-controlling the drive motor.

[0010] The drive controller can in particular include a computing device, such as a programmable controller (SPS), which performs the simulation and, for example, stores the simulation model. In addition, the drive controller can include power components, in particular power transistors, which electrically control the drive motor. The drive controller can preferably be directly connected to the drive motor, for example, by means of electrical connection lines. In particular, the components of the drive controller can be accommodated in a single housing.

[0011] The drive controller can be installed in an industrial device. In the device, the drive motor drives a mechanical device, wherein the mechanical device includes one or more coupled components. In this case, coupling is to be understood as coupling mechanically and / or in an effectively driving manner. The drive motor can be one of the components of the mechanical device. For example, the drive motor can drive a drive shaft, wherein the drive shaft can in turn be coupled to a plurality of other components, such as a transmission rod, a transmission device, etc. Now, the components of the mechanical device, i.e., for example, the drive shaft, the transmission rod, the transmission device, etc., can be stored and / or simulated in the simulation model by means of data.

[0012] The drive controller may also control multiple drive motors, which in turn drive separate drive shafts. The multiple drive motors and shafts may be included in one simulation model, or mapped into separate simulation models.

[0013] Advantageous embodiments of the invention emerge from the following description and the drawings.

[0014] According to an advantageous first embodiment, the simulation model includes information about the structure of the mechanical device. The information about the structure of the mechanical device is used in the simulation. The information may include, for example, the number of components, the mass, moment of inertia, position, etc. of at least one or all components.

[0015] According to another advantageous embodiment, the simulation model comprises at least one transfer function, which describes the characteristics of at least a part of the components of the mechanical device. More precisely, the transfer function can describe the movement of the first component in relation to the movement of the second component coupled to the first component. Based on the transfer function, for example, the movement of the component directly or indirectly coupled to the drive motor can be inferred from the known rotation / movement of the motor using the simulation model example, and the movement of the component coupled to the drive motor can be calculated. For example, the drive motor can move the slider back and forth via a connecting rod. For this purpose, the simulation model can include corresponding transfer functions, so that, for example, the current position, velocity and acceleration of the slider can be determined / calculated based on the angular position, angular velocity and / or angular acceleration of the motor (or motor shaft).

[0016] Furthermore, the simulation model may also include further transfer functions which give the movement of further components. In particular, a chain of transfer functions for describing the movement of all components of the mechanical device may be included in the simulation model. In particular, all components of the mechanical device may be coupled to one another at least indirectly, so that the movement of a component of the mechanical device causes (all) further components of the mechanical device to move.

[0017] According to another advantageous embodiment, the simulation model comprises a particularly respectively individual, particularly virtual (via data) representation of the components of the mechanical device (or all components of the mechanical device), wherein the representation is preferably recalculated repeatedly. The representation of the component in the simulation model can, for example, comprise one or more values ​​of the component describing physical variables such as: velocity v, acceleration a, position s, mass m, moment of inertia J, angular acceleration α, angular velocity ω and / or friction R of the component. In particular, during the simulation based on the simulation model, the movement of at least one or more components can preferably be calculated based on one of the aforementioned values. In this case, the movement and / or the representation of the movement in the simulation model can be recalculated repeatedly, for example, every 0.5 seconds, every 0.1 seconds, every 0.01 seconds or every 0.001 seconds.

[0018] According to another advantageous embodiment, the simulation model is established based on the secondary simulation model and / or the simulation model is provided with data by the secondary simulation model. The secondary simulation model can be generated and implemented outside the drive controller. In particular, the secondary simulation model is more extensive and more accurate than the simulation model in the drive controller. For example, the secondary simulation model can be established and / or implemented using software such as industrialPhysics.

[0019] According to another advantageous embodiment, the simulation model or the secondary simulation model comprises a digital twin of the device. For example, a digital twin ("digital Twin") can be established based on the design of the device with the aid of software such as industrialPhysics. A digital twin can be a digital model of a device that can be used during the entire life cycle of the device. A digital twin or a simulation model and / or a secondary simulation model can be generated based on the device design (Maschinen-Projekt), so that the establishment is associated with only a small cost. The device design can be the design of the device according to design software (e.g. CAD software). In the design software, the functions and arrangements of the components can be determined and displayed accordingly.

[0020] In particular, when performing a simulation, the drive controller performs mathematical calculations based on the simulation model.

[0021] According to another advantageous embodiment, as already mentioned above, the simulation model and / or the secondary simulation model is created based on the CAD model of the device. This simplifies and speeds up the creation of the simulation model, since many or all data about the device are already present in the CAD model, and only these data need to be transferred to the simulation model. The transfer to the simulation model can be carried out by a predefined transformation algorithm. The CAD model can in particular be a three-dimensional model of the device.

[0022] According to another advantageous embodiment, the simulation is preferably performed in real time during operation of the device. In this context, real time means that the simulation is at least as fast as the actual operation of the device. In particular, the simulation can simulate the state of the device accordingly, since each mechanical state is known to the simulation. Thus, the required pre-control of the drive motor can be determined and carried out in real time. For example, it may be recognized in the simulation that an increased load will be applied to the drive motor within a short period of time. In the course of the pre-control, the torque output from the drive motor to the mechanical device can then be increased in a timely manner.

[0023] In particular, the simulation can calculate the actual state of the device in real time and / or before the actual state, in particular at least 10 ms or at least 5 ms or at least 1 ms, for example 100 ms before the actual state. In addition, the simulation can be synchronized with the actual state of the device, in particular by measuring the actual torque demand of the drive motor. With the help of the transfer function of the mechanical device, for example, the speed v, acceleration a, position s, angular acceleration α, angular velocity ω and / or angular position x of one or more components can be determined. In addition, mechanical parameters of one or all components of the mechanical device, such as mechanical moment of inertia, speed-dependent friction and / or static friction, can be determined here by the measured torque demand, as described in EP 19180500.1.

[0024] That is, in the simulation, the future force and / or torque requirements of the drive motor or the force and / or torque requirements expected in real time can be calculated. Then, the precontrol can be performed corresponding to the calculated force and / or torque requirements.

[0025] According to another advantageous embodiment, the simulation is performed using the program code of the drive controller. This means that the simulation is performed by a code that is also used for conventional control of the drive motor by the drive controller. For example, the simulation model can be stored in a library of the code of the drive controller. Thus, no separate software is required to simulate the device. In addition, the data generated in the simulation can be further processed in the same program code and used for pre-controlling the device. Thus, pre-control can be realized very simply and only suffers from small delays, because no data transmission, etc. is required between different control units.

[0026] According to another advantageous embodiment, the drive controller is divided into a head controller and a motor controller, wherein the simulation and precontrol are performed by the head controller. The head controller can be formed, for example, by the aforementioned SPS, while the motor controller can be formed by a power part (with the aforementioned power transistor) of the drive controller. The motor controller can, for example, receive position and / or speed and / or torque requirements from the head controller and implement these requirements. For this purpose, the motor controller can, for example, include a PID regulator.

[0027] According to another advantageous embodiment, the motor can be designed and / or selected using simulation, wherein the simulation is performed in the drive controller, in particular before the device is put into operation. By means of the simulation, for example, the torque requirement for the drive motor can be determined for each possible operating state of the device before the device is put into operation, or even before the device is built. Thus, the drive train (a combination of drive controller, motor and transmission) can be appropriately designed and / or selected. That is, it is advantageous that, based on the simulation, the effective power or size of the required drive train can be selected based on loadable data, in particular in devices with complex mechanical devices. This avoids the drive train or the drive motor being designed to be too large and therefore too expensive.

[0028] The computing device for equipment design can be a computer, on which CAD software for equipment design is implemented. Then, a simulation model and / or a secondary simulation model can be generated according to the CAD software for equipment design, for example, using industrialPhysics software. To this end, the CAD software, for example, transmits its CAD data to industrialPhysics. Accordingly, the simulation of the secondary simulation model can be implemented based on the CAD data, thereby simulating the industrial equipment. The simulation of the secondary simulation model can be implemented by the computing device for equipment design or another computing device. Then, before the industrial equipment is put into operation, the data of the secondary simulation model can be partially or completely transmitted to the drive controller.

[0029] Then, with the help of secondary simulation models, further simulations can be performed to design and / or select motors before the industrial equipment is put into operation.

[0030] More precisely, in particular before or during the commissioning of the device (i.e. in an initialization phase), a computing device of the device design and a drive controller can be coupled by means of a data connection. The drive controller can then simulate the course of the movement of the drive motor (or multiple drive motors) by means of a kinematic setpoint value generator, for example. For this purpose, the drive controller can execute a sequence program (Ablaufprogramm) for controlling the subsequent operation of the device, process it, and output the corresponding angular position, angular velocity and / or angular acceleration of the drive motor or multiple drive motors at multiple points in time by means of the kinematic setpoint value generator. In this way, for example, a motion profile can be adjusted by means of a kinematic setpoint value generator without actually controlling the drive motor.

[0031] The data on the angular position, angular velocity and / or angular acceleration determined at a plurality of points in time by means of the kinematic setpoint value generator are then fed into the secondary simulation model. The secondary simulation model thus contains not only the CAD data but also the kinematics to be expected during operation of the device. The device is then preferably completely simulated using the secondary simulation model.

[0032] In particular, the movement of components of the mechanical device is simulated with the aid of the secondary simulation model, wherein the movement parameters and / or the mechanical parameters obtained in the simulation can be transmitted to the drive controller.

[0033] Preferably, the drive controller generates one or more transfer functions of the mechanical device of the device according to the motion parameters. In other words, the simulation model of the drive controller is improved or generated based on the simulation data of the secondary simulation model.

[0034] Preferably, the transfer function is stored in the drive controller, in particular in the library mentioned, in the form of a value table of value pairs. The value pairs respectively give the motion parameters of the drive component and the motion parameters of the associated driven component. The value table of the value pairs of the mechanical component represents the transfer function of the component. Based on the value pairs / transfer function, the required motion parameters can be quickly determined in operation. In addition, the value table uses a small amount of storage space in the drive controller. For example, the value table can include at least 20 value pairs or up to 36 value pairs, or up to 500 or 2600 value pairs.

[0035] Alternatively, the secondary simulation model may be completely transmitted to the drive controller, and then the drive controller performs simulation using the secondary simulation model.

[0036] In the operating phase after the initialization phase, there is preferably no data connection between the drive controller and the computing device of the device design and / or the computing device implementing the secondary simulation model. The simulation model of the drive controller and the secondary simulation model do not exchange data accordingly. In the operating phase, the device can perform its control operation and, for example, actually execute the mentioned sequence program.

[0037] During the operation phase, the drive controller simulates the device with the aid of the simulation model and pre-controls the drive motor based on the simulation results, as described herein.

[0038] According to another advantageous embodiment, when the device is put into operation and / or during the operation of the device (i.e. in the operating phase), the parameters of the components of the mechanical device are measured, and the simulation model and / or the secondary simulation model are then preferably updated using the measured parameters. The determined or measured parameters are to be understood as, for example, the motion parameters and / or mechanical parameters of the components of the mechanical device mentioned above. The motion parameters give, for example, the speed, acceleration or position of the components of the mechanical device. The mechanical parameters are to be understood in particular as torques, forces and / or constants for calculating torques or forces, for example based on acceleration or speed.

[0039] In particular, the torque output by the drive motor to the mechanical device is measured, and the corresponding angular position of the drive motor is additionally determined and / or measured. Then, the angular acceleration and angular velocity of the drive motor can be calculated based on the angular position. In addition, the corresponding position, speed and acceleration of the remaining components of the mechanical device can be calculated based on the angular position of the drive motor by means of the transfer function of the mechanical component. In addition, the force and / or torque generated by each component can be determined by measuring the torque output by the drive motor to the mechanical device based on such known speed, acceleration and position of the component. For this purpose, in particular, the measurement can be repeated. Then, under the condition of noting the transfer function of the mechanical component, a system of equations is established based on the physical relationship between the motion parameter and the mechanical parameter, and the system of equations, for example, includes one equation for each measurement. The system of equations preferably includes as many or more equations as compared to the unknown number, so that the system of equations can be solved. This is described in detail in the European patent application EP 19180500.1 of the same applicant. The disclosure of the European patent application EP 19180500.1 is fully included here, especially in the calculation of the mechanical parameters of the mechanical device, and is included in the present disclosure by reference.

[0040] More precisely, the drive controller can continuously measure the parameters during the operation phase. The measured parameters can be stored in the drive controller. After a predetermined time interval, in the case of maintenance, and / or when the change of at least one measured parameter exceeds the tolerance value, it is possible to return to the initialization phase, that is, the drive controller can be coupled to the computing device again, and the secondary simulation can be run on the computing device. Then, the measured and stored parameters can be transmitted to the device design, and then the secondary simulation model can be updated and / or improved based on the measured parameters. Subsequently, as described above, the simulation of the updated secondary simulation model can be re-executed, wherein the transfer function in the drive controller is updated. That is to say, the simulation model in the drive controller is also updated in this way. Afterwards, it can be transferred to the operation phase again, in which, as already mentioned, the drive controller is decoupled from the secondary simulation model.

[0041] According to another advantageous embodiment, the simulation model is updated after predetermined time intervals and / or after predetermined events. As already implied above, the simulation model can be updated after a predetermined number of operating hours, wherein, for example, the device is measured after a predetermined number of operating hours in order to update the simulation model. In particular, before the update, the parameter values ​​according to the simulation model can be compared with the corresponding real measured values ​​and mechanical changes can be detected in this way. In addition, a certain set of parameters can be stored accordingly and, based on its time course, future mechanical properties can be inferred, for example with regard to wear.

[0042] The mentioned events can be, for example, maintenance, replacement of components and / or removal or addition of mechanical components. In this case, for example, the simulation model can be adjusted accordingly without taking measurements. Measurements can also be taken in order to be able to determine the influence of the event more accurately.

[0043] Another subject of the invention is an industrial plant having a drive motor, in particular an electric drive motor, a mechanical device having one or more components, and a drive controller, wherein the drive controller controls the drive motor and the drive motor drives the mechanical device. The industrial plant is characterized in that the drive controller is designed to simulate the mechanical device of the plant with the aid of a simulation model and to pre-control the drive motor based on the simulation.

[0044] Industrial plants may be designed, for example, for processing workpieces and / or for sorting and transporting articles.

[0045] The statements about the method according to the invention apply correspondingly to the industrial plant according to the invention. This applies in particular with regard to advantages and preferred embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention is described below purely by way of example with reference to the accompanying drawings.

[0047] Figure 1 shows the schematic structure of the device;

[0048] Figure 2 The establishment of the simulation model is schematically shown;

[0049] Figure 3 The use of the simulation model during operation of the plant is schematically shown. DETAILED DESCRIPTION

[0050] Figure 1 The device 10 is shown in which a motor 12 moves a slider 14 back and forth. To this end, the motor 12 drives a crank 16, which in turn moves the slider 14 via a push rod 18. The motor 12 is driven by a drive controller 26 (see Figure 2 and Figure 3 )control.

[0051] In this case, the electric motor 12 and the crank 16 are together regarded as a first component K1 , and the slide 14 and the push rod 18 are together regarded as a second component K2 .

[0052] The structure of the device 10 shown here is purely exemplary and serves only to explain the creation of a simulation model. Here, a simulation model can also be created for a significantly more complex device 10 having multiple components.

[0053] Figure 2 The process of building a simulation model, i.e. the initialization phase, is shown. To this end, a three-dimensional model of the device 10 is generated using CAD software 20. The three-dimensional model is transmitted to a simulation environment 22 (eg IndustrialPhysics).

[0054] In the simulation environment, firstly, a secondary simulation model 25 is generated based on the three-dimensional model.

[0055] In the initialization phase, the simulation environment 22 is coupled to the drive controller 26. In the initialization phase, the drive controller 26 executes an execution program 28 with the aid of a kinematic setpoint value generator (not shown). The kinematic setpoint value generator repeatedly supplies the simulation environment 22 with the (simulated) angular position f of the drive shaft of the electric motor 12. The simulation environment 22 calculates the corresponding position x of the slide 14 based on the angular position f with the aid of a secondary simulation model 25.

[0056] The position x of the slide 14 is then transmitted to the drive controller 26, wherein the drive controller 26 generates a transfer function x(f) as a function of the angular position f and the position x of the slide, the transfer function x(f) thus being part of the simulation model 24. The transfer function x(f) is stored in the drive controller 26 as a value table with a plurality of value pairs (f and x).

[0057] Furthermore, mechanical parameters of the mechanical device of the device 10 are provided or calculated in the simulation environment 22. For example, the moment of inertia (JLoad) to be overcome by the motor 12 as a whole, the speed-dependent torque (VISC) to be overcome by the motor 12, and the static torque (STAT) to be overcome by the motor can be determined. The drive controller 26 forms a simulation model 24 based on the transfer function x(f) and the determined or given parameters. The simulation environment 22 transmits the data required for this, for example, by means of a data line based on a secondary simulation model 25.

[0058] Figure 3 The use of the simulation model 24 in operation is shown. That is, Figure 3 The operating phase is shown. When the device 10 is in operation, there is no connection between the drive controller 26 and the simulation environment 22, but only the simulation model 24 is executed by the drive controller 26. In this case, the execution program 28 accesses the simulation model 24 and performs a simulation based on the simulation model 24. The execution program 28 performs a precontrol 30 of the motor 12 based on the data obtained in the simulation, such as the torque to be applied / provided by the motor 12, in order to thereby achieve better operating characteristics of the motor 12.

[0059] In addition, the simulation model 24 and the secondary simulation model 25 can be updated and / or improved by measuring the device 10. For this purpose, the simulation environment 22 and the drive controller 26 can be coupled to each other, such as Figure 2 As shown. Improvements and / or updates can also be made in the drive controller 26 itself. Alternatively or additionally, improvements and / or updates can also be made in the simulation environment 22, for which purpose the drive controller 26 can transmit the measured values ​​to the simulation environment 22, such as in Figure 2 Indicated by arrows.

[0060] Reference numerals list

[0061] 10 Equipment

[0062] 12 Motor

[0063] 14 Sliders

[0064] 16 Crank

[0065] 18 Putter

[0066] 20CAD software

[0067] 22Simulation Environment

[0068] 24 simulation models

[0069] 25 Secondary Simulation Model

[0070] 26 drive controller

[0071] 28 Execution Program

[0072] 30 Pre-control

[0073] K1 first component

[0074] K2 Second Component

[0075] fMotor movement

[0076] x(f) transfer function

Claims

1. A method for controlling an industrial device (10) having an electric drive motor (12), wherein: A drive controller (26) controls the drive motor (12), and the drive motor (12) drives a mechanical device having one or more coupled components (K1, K2), wherein the method comprises: The drive controller (26) simulates the mechanical device of the device (10) by means of a transfer function as part of the simulation model (24) and pre-controls the drive motor (12) based on the simulation results. wherein the transfer function describes the properties of at least some of the coupled components (K1, K2) of the mechanical device, and Therein, the transfer function is a table relating the value of a first parameter describing the movement of a first component of the components of the mechanical device to the value of a second parameter describing the movement of a second component of the components of the mechanical device, the second component being coupled to the first component.

2. The method according to claim 1, in, The simulation model (24) includes information about the structure of the mechanical device.

3. The method according to claim 1, in, The simulation model (24) includes representations of components (K1, K2) of a mechanical device.

4. The method according to claim 1, in, The simulation model (24) includes a representation of components (K1, K2) of a mechanical arrangement, wherein the representation is recalculated repeatedly.

5. The method according to claim 1, in, The simulation model (24) is established based on a secondary simulation model (25), and / or the secondary simulation model (25) provides data to the simulation model (24).

6. The method according to claim 5, in, The secondary simulation model (25) is generated and / or executed outside the drive controller (26).

7. The method according to claim 1, in, The simulation model (24) is established based on the CAD model of the device (10).

8. The method according to claim 1, in, The simulation is performed in real time during operation of the device (10).

9. The method according to claim 1, in, When performing the simulation, the force and / or torque requirements of the drive motor (12) that are expected in real time are calculated.

10. The method according to claim 1, in, The simulation is performed using the program code of the drive controller (26).

11. The method according to claim 1, in, The drive controller (26) is divided into a head controller and a motor controller, wherein the simulation and pre-control are performed by the head controller.

12. The method according to claim 1, in, The simulation is used to design and / or select a drive motor (12).

13. The method according to claim 1, in, A drive motor (12) is designed and / or selected using simulation, wherein the simulation is performed in the drive controller (26) before the device is put into operation.

14. The method according to claim 1, in, When the device (10) is put into operation and / or during the operation of the device, parameters of the components (K1, K2) of the mechanical device are measured, and the simulation model (24) is then updated using the measured parameters.

15. The method according to claim 1, in, Accordingly, the simulation model (24) is updated after predetermined time intervals and / or after predetermined events.

16. The method according to claim 1, wherein: The transfer function relates one of a translational velocity and a translational position of the first component to one of a rotational position and a rotational velocity of the second component.

17. An industrial plant (10) comprising an electric drive motor (12), a mechanical device having one or more coupled components (K1, K2) and a drive control (26), wherein: The drive controller (26) is configured to control the drive motor (12), and wherein the drive motor (12) drives the mechanical device. The drive controller (26) is configured to simulate a mechanical device of the device (10) using a transfer function as part of a simulation model (24) and to pre-control the drive motor (12) based on the simulation result. wherein the transfer function describes the properties of at least some of the coupled components (K1, K2) of the mechanical device, and Therein, the transfer function is a table relating the value of a first variable describing the movement of a first component of the mechanical device to the value of a second variable describing the movement of a second component of the mechanical device, the second component being coupled to the first component (K1).

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