METHOD OF CONTROLLING A DRIVE MOTOR

Abstract

The invention relates to a method of controlling a drive, in particular an electric drive, of an industrial machine, in which method a drive control controls a drive motor and the drive motor drives a mechanical system having one or more coupled components. The method is characterized in that the drive control carries out a simulation of the mechanical system of the machine by means of a simulation model and performs a feedforward control of the drive motor based on the simulation.

Claims

1. A method of controlling a drive motor (12) of an industrial machine (10), in which method a drive control (26) controls the drive motor (12) and the drive motor (12) drives a mechanical system having one or more coupled components (K1, K2), characterized in that the drive control (26) carries out a simulation of the mechanical system of the machine (10) by means of a simulation model (24) and performs a feedforward control of the drive motor (12) based on the simulation.

2. The method in accordance with claim 1, wherein the simulation model (24) comprises information on the structure of the mechanical system.

3. The method in accordance with claim 1, wherein the simulation model (24) comprises at least one transfer function which describes the behavior of at least some of the components (K1, K2) of the mechanical system.

4. The method in accordance with claim 1, wherein the simulation model (24) comprises a representation of the components (K1, K2) of the mechanical system, with the representation preferably being recalculated repeatedly.

5. The method in accordance with claim 1, wherein the simulation model (24) is created on the basis of a secondary simulation model (25) and/or is supplied with data from the secondary simulation model (25).

6. The method in accordance with claim 5, wherein the secondary simulation model (25) is generated and/or executed outside the drive control (26).

7. The method in accordance with claim 1, wherein the simulation model (24) is created from a CAD model of the machine (10).

8. The method in accordance with claim 1, wherein the simulation is carried out in real time during the operation of the machine (10).

9. The method in accordance with claim 1, wherein at least one of a force requirement and a torque requirement of the drive motor (12) expected in real time is calculated in the simulation.

10. The method in accordance with claim 1, wherein the simulation is carried out using the program code of the drive control (26).

11. The method in accordance with claim 1, wherein the drive control (26) is divided into a head control and a motor control, with the simulation and the feedforward control being carried out by the head control.

12. The method in accordance with claim 1, wherein the simulation is used for designing and/or selecting the drive motor (12), with the simulation being executed before the putting into operation of the machine.

13. The method in accordance with claim 12, wherein the simulation is being executed in the drive control.

14. The method in accordance with claim 1, wherein measurements of parameters of the components (K1, K2) of the mechanical system are performed on the putting into operation and/or during the operation of the machine (10), whereupon the simulation model (24) is updated with the measured parameters.

15. The method in accordance with claim 1, wherein the simulation model (24) is in each case updated after a predetermined time interval and/or after a predetermined event.

16. An industrial machine (10) comprising a drive motor, a mechanical system having one or more components (K1, K2), and a drive control (26), wherein the drive control (26) controls the drive motor (12) and the drive motor (12) drives the mechanical system, characterized in that the drive control (26) is configured to execute a simulation of the mechanical system of the machine (10) by means of a simulation model (24) and to perform a feedforward control of the drive motor (12) based on the simulation.

17. The industrial machine of claim 16, wherein the drive motor is an electric drive motor.

Description

[0046] The invention will be described below purely by way of example with reference to the drawings. There are shown:

[0047] FIG. 1: the schematic design of a machine;

[0048] FIG. 2: schematically the creation of a simulation model; and

[0049] FIG. 3: schematically the use of the simulation model during the operation of the machine.

[0050] FIG. 1 shows a machine 10 in which a motor 12 moves a slide 14 to and fro. For this purpose, the motor 12 drives a crank 16 which in turn moves the slide 14 via a connecting rod 18. The motor 12 is controlled by a drive control 26 (see FIG. 2 and FIG. 3).

[0051] In this respect, the motor 12 together with the crank 16 is considered as the first component K1 and the slide 14 together with the connecting rod 18 is considered as the second component K2.

[0052] The design of the machine 10 shown here is purely exemplary and only serves to illustrate the creation of the simulation model. The simulation model can in this respect also be created for considerably more complex machines 10 having a plurality of components.

[0053] FIG. 2 shows the procedure for creating a simulation model, i.e. the initialization phase. For this purpose, a three-dimensional model of the machine 10 is generated by CAD software 20. The three-dimensional model is transferred to a simulation environment 22 (e.g. industrialPhysics).

[0054] In the simulation environment, a secondary simulation model 25 is first generated from the three-dimensional model.

[0055] The simulation environment 22 is linked to the drive control 26 in the initialization phase. In the initialization phase, the drive control 26 executes an execution program 28 by means of a movement setpoint generator (not shown). The movement setpoint generator repeatedly supplies the (simulated) angular position f of the drive axis of the motor 12 to the simulation environment 22. The simulation environment 22 calculates the respective position x of the slide 14 from the angular position f by means of the secondary simulation model 25.

[0056] The position x of the slide 14 is then transmitted to the drive control 26, wherein the drive control 26 generates a transfer function x(f) from the angular position f and from the position x of the slide, said transfer function x(f) then being part of a simulation model 24. The transfer function x(f) is stored as a value table having a large number of value pairs (f and x) in the drive control 26.

[0057] Mechanical parameters of the mechanical system of the machine 10 are additionally provided or calculated in the simulation environment 22. For example, the overall moment of inertia (Jload) to be overcome by the motor 12, 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 in this respect. The drive control 26 forms the simulation model 24 from the transfer function x(f) and from the determined or specified parameters. The data required for this purpose is transferred from the secondary simulation model 25 from the simulation environment 22 by means of a data line, for example.

[0058] The use of the simulation model 24 in operation is shown in FIG. 3. FIG. 3 therefore shows the operating phase. In the operation of the machine 10, there is no connection between the drive control 26 and the simulation environment 22, but the simulation model 24 is rather solely executed by the drive control 26. An execution program 28 accesses the simulation model 24 in this respect and carries out a simulation based on the simulation model 24. Based on the data obtained in the simulation, e.g. a torque to be applied/to be provided by the motor 12, the execution program 28 carries out a feedforward control 30 of the motor 12 to achieve an improved running behavior of the motor 12 in this manner.

[0059] In addition, the simulation model 24 and also the secondary simulation model 25 can still be updated and/or improved by measurements at the machine 10. For this purpose, the simulation environment 22 and the drive control 26 can be coupled to one another again, as shown in FIG. 2. The improvement and/or the update can also be performed in the drive control 26 itself. Alternatively or additionally, the improvement and/or the update can also take place in the simulation environment 22. For this purpose, the measurements can be transferred from the drive control 26 to the simulation environment 22, as shown by an arrow in FIG. 2.

REFERENCE NUMERAL LIST

[0060] 10 machine [0061] 12 motor [0062] 14 slide [0063] 16 crank [0064] 18 connecting rod [0065] 20 CAD software [0066] 22 simulation environment [0067] 24 simulation model [0068] 25 secondary simulation model [0069] 26 drive control [0070] 28 execution program [0071] 30 feedforward control [0072] K1 first component [0073] K2 second component [0074] f motor movement [0075] x(f) transfer function