Method for operating drive system, computer program product, control unit and industrial application

Abstract

The invention relates to a method (100) for operating a drive system (50) with a control unit (70) having at least one first regulator (10). The drive system (50) forms an adjustment path (30) belonging to the first adjuster (10). The method (100) comprises a first step (110) in which the first regulator (10) is operated in an active operating state, at least one first regulation input variable (12) being fed and at least one first regulator output variable (14) being output. Furthermore, the method (100) comprises a second step (120) in which a path model (40) is operated, which replicates the behavior of the adjustment path (30) when the disturbance function is transmitted. Furthermore, a third step (130) pertaining to the method (100), in which a first path model output signal (42) is determined, which is combined with the first regulator output variable (14) in order to form the regulated path input variable (16), is carried out. The invention likewise relates to a computer program product (60) and a control unit (70), which is equipped with such a computer program product, wherein such a method (100) can be carried out. The invention further relates to a correspondingly designed industrial application (80).

Description

Technical Field

[0001] The invention relates to a method for operating a drive system and a computer program product, by means of which such a method can be put into practice. The invention also relates to a control unit, which is designed to execute such a computer program product. The invention also relates to an industrial application, which is equipped with such a control unit. Background Art

[0002] Publication US 2002 / 0177909 A1 shows a control system for multivariable control which can be used in industrial processes, in particular in papermaking. A method is implemented using the control system, wherein a prediction model is used which predicts the process state and takes into account the model loop delay.

[0003] Patent US 6,219,196 B1 discloses a control system for a computer hard disk which is designed to suppress mechanical resonances. For this purpose, the frequency characteristic of the control loop is determined and filtered through two band-stop filters. Summary of the invention

[0004] Drive systems are used in many industrial applications which require precise control. In particular, efforts are made to achieve increased positioning accuracy, increased running smoothness and reduced wear. For this purpose, interference influences are compensated which act on the drive system during operation. The object of the present invention is to provide a possibility for operating a drive system in such a way that interference influences are effectively suppressed.

[0005] This object is achieved by a method for operating a drive system according to the present invention, which has a control unit. The control unit has at least one first regulator, which can be designed as a proportional regulator, an integral regulator, a differential regulator or a combination thereof, for example. The drive system forms an affected regulation path assigned to the first regulator. The method includes a first step, in which the first regulator is operated in an activated operating state. The activated operating state includes the operation of the drive system. The first regulator input variable is basically usually delivered to the first regulator in the activated operating state. Similarly, the first regulator output variable is basically usually output by the first regulator at the same time. The regulator output variable is output to the regulation path, that is, the drive system, in order to control the drive system.

[0006] In addition, the method includes a second step, in which a path model is run, by which the behavior of the control path is replicated. For this purpose, the path model can include, for example, a calculation model or a so-called digital twin of the control path. The path model is run in the second step while supplying a disturbance function. The disturbance function adjusts external disturbances, which influence the control path during the activated operation. The disturbance function essentially shows the difference between the actual operation and the idealized operation of the control path. Basically, the disturbance function is usually supplied to the path model.

[0007] Furthermore, the method has a third step in which a first path model output signal is determined. The path model output signal is combined with the first regulator output variable in order to thereby form a control path input variable. The control path input variable is thus an input signal with which the control path, i.e. the drive system, is controlled. The combination of the first path model output signal and the first regulator output variable as the control path input variable is understood, for example, to be an addition or a multiplication of these signals.

[0008] According to the present invention, the path model is designed to minimize the rated-actual deviation of the control path, that is, the control path of the drive system. For this purpose, the path model includes the modeling of the interference function, which, together with at least the first regulator, leads to the minimization of the intervention effect of at least the first regulator on the control path. The rated-actual deviation can be, for example, the deviation between the actual position of the drive system and the rated position. In addition, according to the present invention, the path model is suitable for being operated independently of the state of the control path. The interference function can be constructed as a deterministic description, for example, as a periodic function, in particular a simple harmonic oscillation. In addition, the present invention is based on the surprising recognition that the interference function of the deterministic description is suitable for providing a path model output parameter, that is, at least one first path model output signal, with which the working mode of the first regulator can be supported. This support can also be understood as a relief of the first regulator. Thus, the operation of the drive system is designed to be robust and interference-resistant in a simple manner. The path model with the conveyed interference function can basically be operated separately, so that the control loop belonging to the first regulator can be simply maintained. The path model and the interference function can be configured in a manner that is independent of at least the first regulator, so that simple matching of different control paths, that is, the drive system is feasible. Furthermore, the interference function can be adjusted in a surprisingly simple manner, such as being able to be mapped with reduced computational effort. Accordingly, the method according to the invention has increased adaptability and furthermore supports precise real-time operation of the control path, i.e. the drive system. Thus, the method according to the invention also increases the real-time performance of the control unit.

[0009] In the embodiment of the method claimed, the path model is designed to minimize the output variable of the first regulator. Here, minimization is understood to be basically adjusted to the neutral operation of the regulator, for example, adding zero or multiplying by one. The path model is designed to quantify the direct transmission effect of the interference function on the regulation path and basically compensate it with the path model output signal. The first regulator is shielded from the effect of interference by the path model output signal, and the path model output signal is used to shield the effect of interference for the first regulator, which is copied by the interference function. Therefore, the path model output signal is used for the decoupling of the regulation operation of the first regulator, that is, its idealized operation. Therefore, the structural design of at least the first regulator is simplified. In particular, it is possible to design the first regulator on the idealized operation, that is, on the operation without interference. Again, this situation allows that a particularly precise regulation, in particular a precise position regulation and speed regulation of the drive system, is realized by using the first regulator. In addition, a machine tool drive can be provided by means of the method claimed, which provides increased manufacturing accuracy.

[0010] Furthermore, in the claimed method, in a second step, a control path parameter can be supplied to the path model. The control path parameter can be a physical variable measured in the control path (i.e. on the operating system). The control path parameter can be supplied to the path model as an input periodically, aperiodically or substantially continuously. With the aid of the supplied control path parameter, a misalignment between the control path and the path model, i.e. a bifurcation thereof, can be avoided. Again, this allows it to adjust the first path model output signal more precisely. As a result, the robustness of the drive system (i.e. the control path) against disturbances adjusted using the disturbance function increases.

[0011] Furthermore, the control path (i.e. the drive system) comprises a motor, in particular an electric motor. The control path input variable formed by the first regulator output variable and the first path model output signal can be designed as a motor input variable. The motor input variable can be, for example, a coil current and / or a magnetic field strength or an input voltage. In general, the operation of the motor in the drive system is directly influenced by the motor input variable. The claimed method is suitable for directly influencing the control of the drive system by the path model output signal. Further processing on the motor itself is not necessary.

[0012] In another embodiment of the method claimed, the control unit belonging to the first regulator also has a second regulator. The second regulator is designed to output a second regulator output variable. In addition, the second regulator is connected upstream of the first regulator. Accordingly, the second regulator output variable is used to provide the first regulator input variable for the first regulator. The method claimed is also suitable for use in a regulation system (i.e., a control unit) in which a plurality of regulators act together. Therefore, the method claimed is also suitable for use in complex drive systems and is therefore used in industrial applications.

[0013] In the claimed method, the path model can be designed to output a second path model output signal. The second path model output signal corresponds to the first path model output signal and the first regulator output variable in the third step, and the second path model output signal is combined with the second regulator output variable. Similarly, the combination can be designed as the addition or multiplication of the second regulator output variable and the second path model output signal. In addition, the path model can be designed to minimize the second regulator output variable by means of the second path model output variable (i.e., by means of the second path model output signal), similar to the first regulator output variable. The path model can be matched in a simple manner, that is, by providing the first path model output signal and the second path model output signal, complex control units also use multiple controllers to operate in a compensation manner for interference.

[0014] In addition, in the method claimed, the first regulator output variable can also be determined according to the regulation path parameter. Therefore, in order to determine the first regulator input variable, the second regulator output variable, the second regulator output signal and the regulation path parameter are combined. The regulation path parameter can be a physical variable that is directly measured in the regulation path (i.e., on the drive system) or derived from a physical variable directly measured there. For example, the regulation path parameter can be a motor force. Therefore, the method claimed can be easily adopted on the existing regulation loop constructed as a feedback system. In addition, the surprising cognition based on the present invention that the combination of the existing regulation loop with the path model and the path model output signal further allows the stable operation of the drive system. In particular, the drive system that performs the method claimed shows that the tendency to swing will not be increased. Therefore, in general, for the first regulator and the second regulator, despite the presence of interference, operation is feasible, which basically corresponds to idealized operation.

[0015] In addition, the path model can be designed to output a third path model output signal. The third path model output signal can be combined with the control path parameter to form a first regulator input variable, a second regulator input variable or a regulator input variable of another regulator. Therefore, the path model on which the claimed method is based can be easily extended to even more complex control units, that is, to control units with an increased number of regulators. Therefore, the claimed method can also be applied to complex drive systems. Thus, the path model output signal can be designed for this purpose so that the control path input variable basically operates the associated regulator according to the ideal operation, and the control path input variable minimizes the first regulator input variable and / or the second regulator input variable. Therefore, the design of the control unit is simplified, which again allows the precise operation of the drive system.

[0016] In an embodiment of the method claimed, the path model can be designed to adjust for periodic, fixed-position disturbances on the adjustment path. Such periodic, fixed-position disturbances can be caused, for example, by the vibration behavior of the meshing portion. Accordingly, the path model is designed to contain corresponding interference functions and is determined according to at least the first path model output signal of the path model. Periodic, fixed-position disturbances can be modeled in a simple manner so that the path model can be operated independently of the adjustment path, and the path model takes into account such disturbances in the form of corresponding interference functions. The drift between the adjustment path and the path model (i.e., its bifurcation) is minimized in the case of periodic, fixed-position disturbances. At the same time, multiple extended disturbances can be mapped sufficiently accurately to periodic, fixed-position disturbances. Therefore, in the method claimed, the path model can match multiple disturbances in many aspects.

[0017] Furthermore, in the claimed method, the first controller, the second controller and / or the third controller can be designed as a position controller or a speed controller. The claimed method is used to achieve an increased robustness against interference in the position controller and the speed controller. As a result, the claimed method can be performed at an increased speed, and the claimed method is used to increase the real-time performance for a plurality of industrial applications.

[0018] In other embodiments, the first path model output signal, the second path model output signal and / or the other path model output signal can be designed to be independent of the parameterization of the first regulator, the second regulator and / or the other regulator. Thus, feedback between the regulator and the path model is avoided, which can cause oscillation. For this, the path model can be designed as a dual-mass oscillation system, in which the motor and the load moved by the motor form the oscillating mass. The moving load can be, for example, a tool in a machine tool, in which the drive system moves the tool to a preset position. In the dual-mass oscillation system, the masses can be coupled to each other via elastic elements. Optionally, a damping element can be additionally arranged between the two masses. In such a dual-mass oscillation system, at least one mass can be excited by an interference function. Such a path model does not require knowledge of the regulator, but it takes into account the operating behavior of the drive system. The path model can be operated without an input signal, which characterizes the operating state of the adjustment path in more detail. In addition, the present invention is based on the recognition that the effect of interference can be observed separately from the remaining operating states, and the compensated path model output signal can be determined separately. Alternatively or additionally, the path model can have any other structure that can be described with the aid of Lagrangian mechanics or Hamiltonian mechanics.

[0019] In the claimed method, at least one control path parameter can be a position specification, a speed specification or a motor state variable. In particular, the position specification can be an angular position specification for a drive shaft in the motor, which is to be started. The speed specification can, for example, specify the angular velocity and therefore also the rotational speed, which is achieved with the drive system. The motor state variable can be a coil current, by which a heat release in the motor is preset. Alternatively or additionally, the current temperature in the motor can be used as the motor state variable.

[0020] Furthermore, the path model in the claimed method can include a transfer function from a multi-body system model of the control path. The behavior of the control path (i.e., the drive system) is mapped as a transfer function and can thus be processed by the first controller, the second controller, and / or the further controller as a component of a control loop. The claimed method can be quickly adapted to different application situations, in particular other industrial applications, by virtue of this simplified computability.

[0021] This object is also achieved by a computer program product according to the present invention. The computer program product is designed to receive and process at least one regulator input variable and at least one regulator output variable. According to a path model that also belongs to the computer program product, the receiving and processing of the variables are used to determine at least one regulating path input variable. According to the present invention, the regulating path input variable is determined by means of one of the above-mentioned methods. By means of the claimed method, the computer program product according to the present invention can be executed with reduced computing costs and provide an increased speed. As a result, the computer program product is designed to control the drive system essentially in real time. Here, the concept of real time is understood in the sense of this application, in particular this industrial application. With the help of the computer program product according to the present invention, the claimed method can be applied in a simple manner in an existing drive system, for example, during a retrofit process.

[0022] Furthermore, the above-described objects are achieved by a control unit according to the invention, which is designed to control a drive system. Furthermore, the control unit is designed to output a control signal to the drive system. The control signal is designed as a control path input variable, by which the control path input variable can intervene in the operation of the drive system. According to the invention, the control signal and thereby the control path input variable are determined by means of a computer program product, which is designed according to one of the above-described embodiments. Alternatively or additionally, the control unit is designed to implement at least one of the methods shown above.

[0023] The described objects are also achieved by an industrial application according to the invention, which has a drive system, which is mechanically coupled directly or indirectly to a drive unit. The drive system comprises at least one motor, which can be driven via a control unit. According to the invention, the control unit is designed according to one of the embodiments shown above. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In the following, the present invention is described in more detail according to the embodiments of the accompanying drawings. The embodiments shown in the accompanying drawings can be combined with the above-mentioned features. It is shown in detail:

[0025] FIG. 1 shows a schematic first embodiment of the claimed method. DETAILED DESCRIPTION

[0026] FIG1 schematically shows a first embodiment of the claimed method 100. The method 100 is used to operate a drive system 50, which includes an electric motor 82, which is driven by a control unit 70. The control unit 70 has a first regulator 10 and a second regulator 20, which are connected one after another and can be set by a first regulator parameter 13 or a second regulator parameter 23, respectively. The drive system 50 shows a control path 30, which is characterized by a plurality of control path parameters 33. Accordingly, the control path 30 is shown in FIG1 by a plurality of cells 32, which each map a control path parameter 33. In the continuous operation of the control path 30, a setpoint-actual deviation 36 between an actual variable and a setpoint variable of the control path 30 is adjusted, for example, a setpoint-actual deviation between an actual position and a setpoint position of the drive system 50. The control unit 70 and the regulators 10, 20 act together and form a control path input variable 16, which is used to influence the control path 30 (ie, the drive system 50). The control path input variable 16 shows a control signal 71, with which the control unit 70 influences the drive system 50 and thereby influences the control path 30. The motor input variable for the motor 82 is influenced by the control signal 71. The drive system 50 is connected to a transmission 84 in a torque-transmitting manner, so that a drive power 85 is transmitted to the transmission 84. The transmission 84 and the drive system 50 belong to an industrial application 80, which is driven by the drive system 50. The transmission 84 includes at least one meshing part, not shown in detail, through which a disturbance 86 influences the electric motor 82 (ie, the drive system 50) and thereby influences the control path 30. The disturbance 86 is designed as a periodic, fixed-position disturbance. The method 100 starts from a first step 110, in which the drive system 50 is provided using the control unit 70 in an activated operating state. In this case, the first regulator input variable 12 is supplied to the first regulator 10, which is processed by the first regulator 10. In a first step 110 , first regulator 10 outputs first regulator output variable 14 substantially continuously.

[0027] The method 100 also includes a second step 120, in which a path model 40 is run, by which the behavior of the control path 30 is adjusted. The path model 40 can be designed as a so-called digital twin. During operation, a disturbance function 41 is basically continuously fed to the path model 40, by which the effect of the disturbance 86 caused by the transmission mechanism 84 is adjusted. The delivery of the disturbance function 41 is symbolically represented by an arrow 43. The path model 40 and the disturbance function 41 can be run independently of the control path 30. The mutual behavior between the disturbance function 86 and the path model 40 is described by a dual mass oscillation system. The first path model output signal 42 is determined by the path model 40, and the combination 15 of the first path model output signal and the first regulator output variable 14 is delivered. The first path model output signal 42 is determined from the path model 40 so that the setpoint-actual deviation 36 is minimized, wherein the first regulator output variable 14 is minimized. In this case, minimization is understood to mean that there is essentially a neutral operation of the first regulator 10 between the first regulator input variable 12 and the first regulator output variable 14, for example, adding zero or multiplying by one. For this purpose, the path model 40 includes at least one transfer function 45, which is independent of the regulator parameters 13, 23 and is essentially or exclusively based on the description via the control path 30. The influence of the disturbance 86 on the control path 30 is shown by means of the at least one transfer function 45. For this purpose, the path model 40 is designed to determine at least one path model output signal 42, 44, 46, which essentially corresponds to the inverse of the disturbance function 41. As a result, a compensation of the disturbance 86 in the control path 40 (i.e., in the drive system 50) is obtained at least in part.

[0028] Furthermore, the method 100 comprises a third step 130, in which the first controller output variable 14 is combined with the first path model output signal 42. The combination 15 in the third step 130 can be designed as an addition or a multiplication of the first controller output variable 14 and the first path model output signal 42. The combination 15 forms a control path input variable 16, by which the control path 30 is directly influenced.

[0029] Furthermore, in the claimed method 100, a second path model output signal 44 is determined by the path model 40. The second path model output signal 44 is combined with the second regulator output variable 24 and the control path parameter 33. The first regulator output variable 12 is determined by the combination 25, which can be designed as an addition or multiplication. The regulator parameter 33 is indirectly or directly acquired by a corresponding acquisition device in the control path 30. The second path model output signal 44 is designed for this purpose in such a way that the setpoint-actual deviation 36 is minimized, wherein the second regulator output variable 24 is also minimized. Similar to the minimization of the first regulator output variable 14, the minimization of the second regulator output variable 24 includes that the second regulator 20 essentially uses the associated second regulator output variable 22 to perform a neutral operation.

[0030] A third path model output signal 46 is also transmitted via the path model 40 and is combined with the path parameter 33. The combination 35 can be designed as an addition or multiplication of the path parameter 33 and the third path model output signal 46. The combination 35 forms the second regulator output variable 22.

[0031] By means of the path model 40, the substantial inversion of the disturbance function 41 is formed at an increased speed via the path model output signals 42, 44, 46, thereby providing real-time performance. In this case, the term real-time is understood in conjunction with an industrial application 80, in which a drive system 50 is used. During the method 100, selectable control path parameters 33 are at least partially fed to the path model 40. With the aid of the control path parameters 33 fed back in this way, the plausibility of the state of the control path 40 mapped in the path model 40 can be checked and / or the path model 40 can be updated. The claimed method 100 is implemented with the aid of a computer program product 60, not shown in detail, which can be implemented on a control unit 70.

Claims

1. A method (100) for operating a drive system (50) using a control unit (70), the control unit having at least one first regulator (10) and the drive system (50) being a control path (30) belonging to the first regulator (10), the method comprising the steps of: a) operating the first controller (10) in an activated operating state by supplying at least one first controller input variable (12) and outputting at least one first controller output variable (14); b) running a path model (40) which replicates the behavior of the control path (30) by feeding a deterministically described disturbance function (41); c) determining a first path model output signal (42), which is combined with the first regulator output variable (14) to form a regulation path input variable (16), wherein: The path model (40) is designed to minimize a setpoint-actual deviation (36) of the control path (30) and to provide a first path model output signal (42), an operating mode of the first controller (10) being supported by means of the first path model output signal, characterized in that the path model (40) is designed to minimize the first controller output variable (14) and, for this purpose, is designed to quantify the effect of the disturbance function (41) on the control path (30) which is directly transmitted to the control path (30) and to compensate for it by means of the first path model output signal (42).

2. The method (100) according to claim 1, characterized in that: In step b), a control path parameter (33) is supplied to the path model (40).

3. The method (100) according to claim 1 or 2, characterized in that: The control path (30) comprises a motor (82) and the control path input variable (16) is designed as a motor input variable.

4. The method (100) according to any one of claims 1 to 3, characterized in that: The control unit (70) has a second regulator (20), which is designed to output a second regulator output variable (24) and is connected upstream of the first regulator (10).

5. The method (100) according to claim 4, characterized in that: The path model (40) is designed to output a second path model output signal (44), which is combined with the second regulator output variable (24) to form the first regulator input variable (12).

6. The method (100) according to claim 5, characterized in that: The first controller input variable (12) is also determined with the aid of a control path parameter (33).

7. The method (100) according to any one of claims 1 to 6, characterized in that The path model (40) is designed to output a third path model output signal (46), which is combined with a control path parameter (33) as a controller input variable (12, 22) of the first controller (10), a controller input variable of the second controller (20) or a controller input variable of another controller.

8. The method (100) according to any one of claims 1 to 7, characterized in that The path model (40) is designed to adjust periodic, stationary disturbances (86) of the adjustment path (30), such as, for example, the vibration behavior of a toothing.

9. The method (100) according to any one of claims 1 to 8, characterized in that The first controller, the second controller and / or the further controller (10, 20) are designed as position controllers or as speed controllers.

10. The method (100) according to any one of claims 1 to 9, characterized in that: The first path model output signal, the second path model output signal and / or the further path model output signal (42, 44, 46) are independent of parameterization (13, 23) of the first controller, the second controller and / or the further controller (10, 20).

11. The method (100) according to any one of claims 1 to 10, characterized in that At least one of the control path parameters (33) is in each case a position parameter, a speed parameter or a motor state variable.

12. The method (100) according to any one of claims 1 to 11, characterized in that The path model (40) includes a transfer function (45) according to a multi-body system model of the regulation path (30).

13. A computer program product (60) for receiving and processing a regulator input variable (12, 22), at least one regulator output variable (14, 24), and for determining at least one control path input variable (16) by means of a path model (40), characterized in that: The control path input variable (16) is determined by means of a method (100) according to any one of claims 1 to 12.

14. A control unit (70) for controlling at least one drive system (50), the control unit being configured to output a control signal (71) to the drive system (50), wherein: The control signal (71) is designed as a control path input variable (16), which is determined by a computer program product (60) according to claim 13 and / or by a method (100) according to any one of claims 1 to 12.

15. An industrial application (80), comprising a drive system (50) having a motor (82), the motor being coupled to a control unit (70), characterized in that: The control unit (70) Designed according to claim 14.

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