Method for the automated, measurement data-based design of an electronic controller for a hydraulic system

Abstract

The present invention relates to a method for the automated, measurement-data-based design of an electronic controller for a hydraulic system 100. For this purpose, a predetermined measurement routine is performed on the hydraulic system 100, during which measurement data of measurement parameters of the hydraulic system 100 are automatically acquired. Based on this measurement data, a computer-based model structure is trained, i.e., the behavior of the hydraulic system 100 is automatically identified. Based on system equations automatically extracted from the computer-based model structure, an electronic controller is automatically synthesized and subsequently automatically embedded in a control unit 12 of the hydraulic system 100 in order to control at least one controlled variable, such as a pressure, a volume flow, a position, or a path, in the hydraulic system 100.The automated steps of the method can be performed by an external device 30 which is connected to the hydraulic system 100 via a data communication interface for this purpose.

Description

The present invention relates to a method for the automated, measurement data-based configuration of an electronic controller for a hydraulic system, to a device for the automated, measurement data-based configuration of an electronic controller for a hydraulic system, to a method for controlling at least one controlled variable in a hydraulic system, and to a hydraulic system.Hydraulic systems are used in the most varied technical fields and comprise at least one hydraulic consumer which is supplied with pressurized hydraulic fluid from a pressure source, for example a pump element or an accumulator, in order to carry out work. Such a hydraulic consumer is regularly controlled via a valve or a plurality of valves in order to regulate the fluid flow conducted to the hydraulic consumer and / or the fluid flow conducted from the hydraulic consumer to a reservoir. Conventionally, translatory or rotatory hydraulic consumers are used as hydraulic consumers. Depending on the complexity of the hydraulic system or on requirements for the accuracy of the hydraulic system, it may be necessary or desirable to control one or more control variables in the hydraulic system during operation of the hydraulic system. Control variables which are considered in classical terms are parameters of the hydraulic system, such as pressures, volume flows, paths, positions or temperatures. The paths and positions can be, for example, on the one hand paths and positions of a valve element, such as a valve piston, for example, or also axial or radial paths and (angular) positions of a translatory or rotatory hydraulic consumer, such as a piston rod of a hydraulic cylinder, for example.As regulators for hydraulic systems, both mechanical regulators and electronic regulators are known in the prior art, wherein PID regulators are most frequently used as electronic regulators. Both mechanical and electronic regulators present problems in practice. Mechanical regulators suffer from problems caused by wear, for example, are not very flexible, are subject to inaccuracies due to series scattering and are prone to oscillations. In addition, in the case of mechanical regulators, individual adaptation to an overall system is not possible. Electronic controllers, such as PID controllers, suffer, for example, from the fact that their design and thus the control quality is strongly dependent on the person setting and the conditions actually prevailing in the hydraulic system, they are usually truly performant only at a few working points and an adaptation of the controller to changing conditions is not possible.In addition, in practical application, there are frequently other problems with the controller design. As a rule, predefined mathematical or simulative models of the hydraulic system to be regulated are inaccurate, for example, on the basis of incomplete or information that is difficult to determine. Moreover, for cost reasons, it is frequently to be assumed that there is only a few sensor systems in the hydraulic system to be regulated, which makes precise regulation of the hydraulic system based on incomplete measurement data more difficult. The available capabilities of an electronic control unit of the hydraulic system to be controlled, such as computing power or storage space, are frequently a limiting factor, especially in the case of mobile hydraulic systems. Non-linearities characteristic of hydraulic systems, which are caused, for example, by hysteresis or friction effects, likewise frequently lead to an impairment in the controller design.In the prior art, for example, U.S. Pat. No. 2021 / 0 173 376 A1 discloses a method for monitoring a hydraulic device on the basis of methods of machine learning for the purpose of predictive maintenance (predictive maintenance).For example, CN 113 006 188 B describes a method for automatically adapting the power of a hydraulically operated excavator as a function of its working stages on the basis of machine learning methods.For example, CN 114 462 459 A discloses a method for the automated diagnosis of fault conditions of a hydraulic press on the basis of methods of machine learning.Against this background, it is an object of the present invention to provide an electronic regulator for a hydraulic system which has a control quality which is improved compared to the known regulators, in order, for example, to increase the throughput, the performance or else the energy efficiency of the hydraulic system, and which is capable of adjusting to non-linearities, dynamics and to a multiplicity of different operating points which prevail in the hydraulic system to be regulated.The object is achieved first of all by a method for the automated, measurement data-based design of an electronic controller for a hydraulic system according to Claim 1.The method according to the invention for automatically designing an electronic controller for a hydraulic system based on measurement data comprises the following steps: defining measurement parameters of the hydraulic system, carrying out a predefined measurement routine on the hydraulic system, automatically acquiring measurement data, in particular time series data, of the measurement parameters of the hydraulic system during the predefined measurement routine, automatically identifying the behavior of the hydraulic system on the basis of the acquired measurement data on the basis of at least one computer-based model structure, automatically extracting system equations of the hydraulic system from the at least one computer-based model structure, automatically synthesizing the electronic controller on the basis of the extracted system equations, and automatically embedding the synthesized electronic controller in an electronic control unit of the hydraulic system for controlling at least one control variable in the hydraulic system.The method according to the invention makes it possible to automatically provide an electronic controller optimized for this specific hydraulic system for any hydraulic system. The method according to the invention links methods of machine learning and (nonlinear) control technology to hydraulic systems for this purpose and is also applicable in particular to already existing hydraulic systems. In addition, the method offers the advantage that it can be repeated at any time in order to adapt the at least one computer-based model structure and thus the synthesized electronic controller to modified boundary conditions, such as modified environmental conditions or wear phenomena, for example, on the basis of newly acquired measurement data. The method according to the invention is thus a concept of hybrid learning, since the electronic controller, once synthesized, initially remains unchanged during the ongoing operation of the hydraulic system, but can be updated again and again subsequently by repeating the method according to the invention.A predefined measurement routine is to be understood in particular as a signal profile which is impressed on at least one actuator in the hydraulic system over a predefined period of time. For example, at least one electrically actuated valve of the hydraulic system (actuator) can be impressed with a signal profile as actuation current. An electrically actuated valve is understood in the present case in particular to mean an electromagnetically actuated valve. However, another form of electrically actuating such a valve is naturally also conceivable, for example via one or more electrically actuated stepping motors. An actuation current of an electrically actuated valve is therefore in particular an actuation current of an electromagnetically actuated valve or an actuation current of a stepper motor for actuating a valve. This actuation current profile must of course be adapted to the respective hydraulic system in order to take into account the boundary conditions and limit values of the respective hydraulic system, such as, for example, a maximum valve energization, a maximum deflection of a consumer or the like. Such an actuation current profile can take the form of a sweep, for example. Alternatively, the actuating current profile can also be used to approach different (random) switching positions of an electrically actuated valve in a step-like manner. Additionally or alternatively, it is of course also possible to change further boundary conditions within the scope of the predefined measurement routine, such as, for example, an external load on the hydraulic system.In particular, the synthesized electronic controller is an algorithm, a formula or a look-up table. Thus, depending on the application, an optimized electronic controller can be provided for the hydraulic system to be controlled.If, for example, particularly little computing capacity is available to the electronic control unit of the hydraulic system to be controlled, the synthesized electronic controller is implemented as a formula or look-up table. In this case, the usual operating points of the hydraulic system to be regulated are sampled as part of the execution of the predefined measurement routine and the ideal regulator parameters are approximated as part of the automated synthesis of the electronic regulator.If sufficient computing capacity of the electronic control unit of the hydraulic system to be controlled is available, the synthesized electronic controller is an algorithm which is evaluated during operation by the electronic control unit for changing operating points. More accurate results and thus a higher control quality can thereby be achieved.In particular, the automated identification of the behavior of the hydraulic system preferably comprises an automated identification of the behavior of each hydraulic consumer of the hydraulic system on the basis of the acquired measurement data on the basis of a computer-based model structure. In other words, a computer-based model structure is identified for each hydraulic consumer of the hydraulic system. Thus, the synthesized electronic controller is specifically designed and optimized for each hydraulic consumer present. This is of course only possible if corresponding sensor systems for capturing the relevant measurement data are present in the hydraulic system to be regulated.Preferably, the step of performing the predetermined measurement routine is an automated performing. By also carrying out the predefined measurement routine in an automated manner, an even higher degree of automation and error minimization is achieved.Advantageously, the computer-based model structure comprises at least one artificial neural network for function approximation. As a result, the system behavior of the hydraulic system to be regulated can be identified particularly efficiently on the basis of the recorded measurement data. Alternatively or additionally, the computer-based model structure can comprise polynomials for function approximation.It is expedient if the computer-based model structure comprises an ANARX structure (additive nonlinear autoregressive exogenous model), an LSTM structure (long short-term memory), an ARMA structure (autoregressive-moving-average) and / or an RNN structure (recurrent neural network). On the basis of these fundamentally known computer-based model structures, preferably on the basis of an ANARX structure, the acquired measurement data can be automatically transferred into a model for predicting the system behavior of the hydraulic system to be regulated. In this case, in particular the ANARX structure offers the advantage that it can be reformulated particularly easily into system equations. However, this is also possible in principle for all other computer-based model structures mentioned.Preferably, the synthesized electronic controller is a robust controller. Deviations of the behavior of the hydraulic system during operation from the behavior identified by the measurement routine can be compensated particularly well by a robust controller. The robust regulator is preferably an H-infinity regulator, an H2 regulator, a back-tapping regulator or a model predictive control regulator.Expediently, the measurement parameters comprise at least one hydraulic parameter of the hydraulic system and at least one actuation current of an electrically actuated valve, in particular an electromagnetically actuated valve or a valve actuated by means of a stepper motor, and the step of automatically acquiring measurement data comprises: automatically acquiring measurement data of at least one hydraulic sensor of the hydraulic system and automatically acquiring measurement data of at least one actuation current of an electrically actuated valve of the hydraulic system. In particular, a control variable of the synthesized electronic controller comprises the at least one actuating current of an electrically actuated valve. In particular, the hydraulic system comprises at least one electrically actuated valve for controlling a hydraulic consumer in each case, and the automated acquisition of measurement data comprises the automated acquisition of all actuating currents of electrically actuated valves of the hydraulic system which are used for controlling the hydraulic consumer.The at least one hydraulic parameter is preferably a pressure and / or a volume flow and the at least one hydraulic sensor is preferably a pressure sensor and / or a volume flow sensor. Alternatively or additionally, the at least one hydraulic parameter can also be a derived value, for example a volume flow derived from the measured travel speed of an electrically actuated valve. Thus, the synthesized electronic controller can be optimized depending on the sensor system present in the hydraulic system to be controlled and the desired controlled variable.It can be expedient if the measurement parameters comprise at least one path and / or one position, in particular of a valve element and / or of a hydraulic consumer, and the step of automatically acquiring measurement data comprises automatically acquiring measurement data of at least one path sensor and / or of a position sensor. If the controlled variable to be controlled comprises a path and / or a position of a valve element and / or of a hydraulic consumer, it is necessary, both for the design of the electronic controller and during the operation of the hydraulic system using the synthesized electronic controller, to record the actual values of this controlled variable via a corresponding path and / or position sensor.Preferably, the measurement parameters comprise all parameters that are metrologically available in the hydraulic system. This comprises in particular all parameters detected by hydraulic sensors in the hydraulic system, all actuating currents of electrically actuated valves in the hydraulic system and all detected travel and / or position parameters of optionally available travel and / or position sensors. By including all parameters of the hydraulic system to be regulated that are available by measurement technology, the accuracy of the synthesized controller can be maximized. In principle, it is also conceivable not to include all parameters of the hydraulic system to be regulated that are available by measurement technology. This can be useful, for example, when a specific, clearly defined control task is to be solved, for which not all parameters available by measurement are required, or when the available capabilities of the electronic control unit of the hydraulic system are particularly limited.It is expedient if the automated steps of the method are carried out by an external device which is connected to the hydraulic system for this purpose via an electronic data communication interface. As a result, the computing-intensive steps of the method can be swapped out and only the actual control during operation can take place via the electronic control unit of the hydraulic system, the capabilities of which are limited.Alternatively, the automated steps of the method can be carried out by the electronic control unit of the hydraulic system. This is possible if the capabilities of the electronic control unit of the hydraulic system are sufficient for carrying out the arithmetic-intensive automated steps.It can also be advantageous if the execution of the predefined measurement routine and the acquisition of measurement data are carried out virtually on the basis of a simulation model of the hydraulic system. In particular in the case of hydraulic systems which are particularly critical in safety, it can thereby be ensured that critical situations do not occur as a result of the execution of the predefined measurement routine, such as uncontrolled movements of a boom, in which, in the worst case, the respective machine is damaged or even users are endangered. In such a case, the method according to the invention is preferably repeated and a reduced predefined measurement routine is carried out on the real hydraulic system during the repetition in order to adapt the electronic controller synthesized on the basis of the simulation model to the real hydraulic system.Furthermore, the object is achieved with a device for the automated, measurement data-based design of an electronic controller for a hydraulic system according to claim 14.The device according to the invention for the automated, measurement data-based design of an electronic controller for a hydraulic system comprises an electronic data communication interface for establishing a mutual data connection with the hydraulic system and an electronic computing unit. The electronic computing unit is designed to carry out the automated steps of the method according to the invention for the automated, measurement data-based design of an electronic controller for a hydraulic system. In particular, the data communication interface is a wireless or a wired, in particular a serial, communication interface.By means of the device according to the invention for the automated, measurement data-based design of an electronic controller for a hydraulic system, the computing-intensive steps of the method according to the invention for the automated, measurement data-based design of an electronic controller for a hydraulic system can be transferred from the electronic control unit of the hydraulic system to the electronic computing unit of the device. Preferably, the device comprises the hydraulic system.Furthermore, the object is achieved with a method for regulating at least one controlled variable in a hydraulic system according to Claim 16.The method according to the invention for regulating at least one controlled variable in a hydraulic system comprises an automated, measurement data-based design of an electronic regulator for the hydraulic system using the method described above for automated, measurement data-based design of an electronic regulator for a hydraulic system and a regulation of the at least one controlled variable in the hydraulic system by the synthesized electronic regulator.By means of the method according to the invention for regulating at least one controlled variable in a hydraulic system, the synthesized regulator optimized with respect to its control quality is able to be set to non-linearities, dynamics prevailing in the hydraulic system and to a multiplicity of different operating points.The at least one controlled variable preferably comprises a pressure, a volume flow, a path and / or a position. These controlled variables represent classical parameters to be controlled in a hydraulic system.Finally, the object is achieved with a hydraulic system according to claim 18.The hydraulic system according to the invention comprises at least one hydraulic consumer, at least one electrically actuated valve, in particular an electromagnetically actuated valve or a valve actuated by means of a stepper motor, for actuating the at least one hydraulic consumer, at least one hydraulic sensor and an electronic control unit. The electronic control unit is designed to carry out the automated steps of the method according to the invention for controlling at least one controlled variable in a hydraulic system.The at least one hydraulic consumer is in particular a translatory or a rotatory hydraulic consumer. As an electrically actuated valve, for example, a 2 / 2-proportional directional control valve, a 3 / 3-proportional directional control valve, a 4 / 3-proportional directional control valve or a 3 / 2-proportional directional control valve can be used. Corresponding switching valves or seat valves can also be used. A black-and-white or binary valve is referred to here as a switching valve, which only has the positions "on" and "on".By using the at least one electrically actuated valve, the actuating current of the at least one electrically actuated valve can be used as the actuating variable of the synthesized controller, i.e. in particular the actuating current of an electromagnetically actuated valve or the actuating current of a valve actuated by means of a stepper motor. Thus, in modern hydraulic systems, electrically actuated valves which are widely used can be used as control elements of the control circuit.Preferably, each hydraulic consumer of the hydraulic system is actuated via at least one electrically actuated valve of the hydraulic system. As a result, one or more controlled variables for each hydraulic consumer of the hydraulic system can be controlled by the synthesized controller. Preferably, during the method according to the invention for the automated, measurement data-based design of the electronic controller for the hydraulic system, a computer-based model structure is identified for each hydraulic consumer of the hydraulic system. Thus, the synthesized electronic controller is specifically designed and optimized for each hydraulic consumer present.Expediently, each electrically actuated valve of the hydraulic system is assigned at least one hydraulic sensor. As a result, the relevant hydraulic parameters of the hydraulic system, such as pressures or volume flows, can be detected in the direct vicinity of the electrically actuated valve (manipulated variable), can be used for the synthesis of the electronic controller and for regulating the at least one controlled variable. For each electrically actuated valve, viewed in the direction of flow to the hydraulic consumer, a pressure before and a pressure after the electrically actuated valve are preferably detected by hydraulic sensors designed as pressure sensors.The invention is explained in more detail below with reference to embodiments shown in the figures. The following are shown schematically: FIG. 1 shows a hydraulic system according to the invention according to a first embodiment; FIG. 2 shows a hydraulic system according to the invention according to a second embodiment; FIG. 3 is a simplified block diagram of the methods according to the invention; and FIG. 4 shows a simplified example of a computer-based model structure in the form of an ANARX structure.An exemplary example of a hydraulic system 100 according to the present invention, in accordance with a first embodiment, is shown in FIG. 1. The hydraulic system 100 comprises two first electrically actuated valves 10, a hydraulic consumer connection A and a hydraulic consumer connection B, a pressure source P, a hydraulic reservoir R, an electronic control unit 12 and six hydraulic sensors 14. The hydraulic consumer is not shown in detail in FIG. 1, but can be a translatory or rotatory hydraulic consumer in a known manner. In principle, it is of course also conceivable for only one inlet or outlet of different hydraulic consumers to be connected to each hydraulic consumer connection A, B.In this embodiment, the first electrically actuated valves 10 are designed as electromagnetically actuated 3 / 3-proportional directional valves, which are each provided for actuating one of the hydraulic consumer connections A and B. For this purpose, each of the first electrically actuated valves 10 is hydraulically connected to the pressure source P, to the hydraulic reservoir R and to one of the hydraulic consumer connections A and B. By continuously or proportionally displacing a valve piston in the first electrically actuated valve 10, the hydraulic consumer connection A or B can be supplied with pressurized hydraulic fluid from the pressure source P or relieved toward the hydraulic reservoir R. The displacement of the valve piston takes place by two electromagnetic actuating devices 16, the energization of which is controlled by the electronic control unit 12. The electromagnetic actuating devices 16 thus function here as actuators. All electromagnetic actuating devices 16 are connected to the electronic control unit 12, even if this is indicated by a dashed line in FIG. 1 by way of example only for one electromagnetic actuating device 16. In the neutral middle position of the first electrically actuated valve 10, all connections are blocked. Two return springs 18 bring the valve piston of the first electrically actuated valve 10 into the neutral central position when the electromagnetic actuating devices 16 are not energized.In this exemplary embodiment, the hydraulic sensors 14 are designed as pressure sensors which record the pressures at the connections of each first electrically actuated valve 10 and pass on their measurement data to the electronic control unit 12. It is of course also conceivable for one or more of the hydraulic sensors 14 to be designed as volume flow sensors. It is likewise conceivable for a plurality of hydraulic sensors 14 to be assigned to a single connection of the first electrically actuated valve 10. Here too, for the purpose of improving clarity, FIG. 1 shows only the connection of a hydraulic sensor 14 to the electronic control unit 12. However, it is obvious to the person skilled in the art that all other hydraulic sensors 14 are also connected to the electronic control unit 12, for example via corresponding cables or also by radio, NFC or Bluetooth. In the present case, all the pressures before and after the first electrically actuated valves 10 are detected by the hydraulic sensors 14, viewed in the direction of flow from the pressure source P to the respective hydraulic consumer connection A and B. Each first electrically actuated valve 10 of the hydraulic system 100 is therefore assigned three hydraulic sensors 14. It is, however, of course also conceivable for no hydraulic sensors 14 to be provided, for example, in the discharge lines to the hydraulic reservoir R.As also shown in FIG. 1, the hydraulic system 100 is connected to an external device 30, which comprises a data communication interface for establishing a mutual data connection with the hydraulic system 100 and an electronic computing unit 32. More specifically, the electronic control unit 12 of the hydraulic system 100 is connected to the data communication interface of the external device 30 via a dedicated data communication interface, which is illustrated as a dashed line in FIG. 1. The data communication interfaces may enable wireless or wired data communication between the electronic control unit 12 and the external device 30. Thus, for example, a WLAN connection or serial interfaces can be used as data communication interfaces. The external device 30 can in this case comprise, for example, a laptop, a tablet, a smartphone, an industrial PC or else a cloud server.FIG. 2 shows a hydraulic system 200 according to a second embodiment. The hydraulic system 200 is different from the hydraulic system 100 according to the first embodiment only in that it includes four second electrically operated valves 20 instead of the two first electrically operated valves 10. In the hydraulic system 200, the hydraulic consumer connections A and B are thus controlled by two second electrically actuated valves 20, respectively. The second electrically actuated valves 20 are designed in this embodiment as electromagnetically actuated 2 / 2-proportional directional valves. A valve piston of the second electrically actuated valve 20 can therefore be continuously switched between a blocking position and a passage position by the electromagnetic actuating device 16. The return spring 18 of the second electrically actuated valve 20 adjusts the valve piston such that the second electrically actuated valve 20 is in the blocking position when the electromagnetic actuator 16 is not energized.As can be seen in FIG. 2, the hydraulic system 200 also comprises hydraulic sensors 14 in each supply line and discharge line to each of the four second electrically actuated valves 20. In the hydraulic system 200 as well, the hydraulic sensors 14 are designed as pressure sensors. However, it is of course also conceivable for one or more of the hydraulic sensors 14 of the hydraulic system 200 to be designed as volume flow sensors. It is likewise conceivable for a plurality of hydraulic sensors 14 to be assigned to a single connection of the second electrically actuated valve 20.It will be apparent to those skilled in the art that the described hydraulic systems 100 and 200 are merely exemplary examples. Thus, for example, only one hydraulic consumer connection A, B can be present in each case or even more than two hydraulic consumer connections A, B. In the hydraulic system 100, the hydraulic consumer connections A, B are actuated by a first electrically actuated valve 10 in each case and in the hydraulic system 200, the hydraulic consumer connections A, B are actuated by two second electrically actuated valves 20 in each case. However, it is also conceivable for only one electrically actuated valve to be provided, which actuates two hydraulic consumer connections A, B. If a hydraulic consumer is thus connected to the two consumer connections A, B, said consumer can be actuated by one, two or four electrically actuated valves. In addition, any further combination of electrically actuated valves for controlling a hydraulic consumer is of course also conceivable, so that a consumer can also be controlled via three, five or more valves.Referring now to Figures 3 and 4, the methods of the present invention will be described.The method according to the invention for automatically designing an electronic controller for the hydraulic system 100, 200 based on measurement data comprises the following steps: defining measurement parameters of the hydraulic system (step S 1 in FIG. 3 ), carrying out a predefined measurement routine on the hydraulic system 100, 200 (step S 2), automatically acquiring measurement data, in particular time series data, of the measurement parameters of the hydraulic system 100, 200 during the predefined measurement routine (step S 3), automatically identifying the behavior of the hydraulic system 100, 200 on the basis of the acquired measurement data on the basis of at least one computer-based model structure (step S 4), automatically extracting system equations of the hydraulic system 100, 200 from the at least one computer-based model structure (step S 5), automatically synthesizing the electronic controller on the basis of the extracted system equations (step S 6), and automated embedding of the synthesized electronic controller in the electronic control unit 12 of the hydraulic system 100, 200 for controlling at least one controlled variable in the hydraulic system 100, 200 (step S 7). Steps S 2 and S 3 take place simultaneously and are also carried out automatically in the present case. It is clear to the person skilled in the art that the carrying out of the measurement routine does not necessarily have to be automated.The defining of the measurement parameters of the hydraulic system 100, 200 comprises a determination of the parameters which are involved in the design of the electronic controller and subsequent to the regulation of at least one controlled variable in the hydraulic system 100, 200. With respect to the hydraulic system 100, the measurement parameters are the detected pressures of the six hydraulic sensors 14 configured as pressure sensors and the operation currents of the two first electrically operated valves 10.In the present case, the consumer of the hydraulic system 100, 200 connected to the hydraulic consumer connections A and B is a hydraulic cylinder. As a measurement routine, the hydraulic cylinder is extended and retracted over a predetermined period of time. For this purpose, the electrically actuated valves 10, 20 which are active in this case are impressed with actuating currents in the form of a sweep. For example, for the extension of the hydraulic cylinder, a sweep is generated in such a way that the flow directions from the pressure source P to the hydraulic consumer connection A and from the hydraulic consumer connection B to the hydraulic reservoir R are always established. For the retraction of the hydraulic cylinder, the sweep is generated in such a way that the flow directions from the pressure source P to the hydraulic consumer connection B and from the hydraulic consumer connection A to the hydraulic reservoir R are always established. The amplitude of the actuating currents of the electrically actuated valves 10, 20 which constantly changes as a result of the sweep generates a continuously changing throughflow, as a result of which the speed of entry and exit of the hydraulic cylinder changes. After each complete cycle (one drive-in, one drive-out), the frequency of the sweep is changed, i.e. increased, for example. Both the starting frequency and the ending frequency and also the number of cycles of the sweep are dependent here on the specific configuration of the hydraulic system 100, 200. The load on the hydraulic system 100, 200 can of course also be changed within the scope of the predetermined measurement routine. For example, a load acting on the hydraulic cylinder from the outside can be applied, changed or removed. In principle, this description of a predetermined measurement routine is only an example and it is obvious to a person skilled in the art that the predetermined measurement routine must be aligned with the specific hydraulic system. In this case, the boundary conditions of the corresponding system, such as, for example, a maximum valve current flow or a maximum deflection of a load, are input into the design of the respective measurement routine.During the execution of the predefined measurement routine on the hydraulic system 100, 200, the measurement parameters of the hydraulic system 100, 200 are acquired as time series data. This means that at discrete points in time a measured value is present for each measurement parameter. This is exemplarily illustrated in FIG. 4, in which a computer-based model structure, in this case an ANARX structure, is illustrated with two measurement parameters for times t- 1 to t-n, by which the behavior of the hydraulic system 100, 200 is automatically identified. In this case, the two measurement parameters are an input variable u, for example the energization of an electrically actuated valve 10 or 20, and a controlled variable y, for example a detected pressure of a hydraulic sensor 14 designed as a pressure sensor.If a position or a path, for example of a valve element of the electrically actuated valves 10, 20 or of a consumer connected to the hydraulic consumer connections A, B, is to be regulated in the hydraulic system 100, 200, a corresponding position or path sensor must be provided in the hydraulic system 100, 200. The measurement data acquired by this position or path sensor are then likewise defined in step S 1 as measurement parameters of the hydraulic system 100, 200.It is clear to the person skilled in the art that not all parameters of the hydraulic system 100, 200 that are available by measurement technology need to find input as measurement parameters in the method according to the invention. However, it is desirable to use as many measurement parameters as possible for the automated, measurement data-based design of the electronic controller in order to achieve the highest possible control quality of the synthesized electronic controller.For the hydraulic systems 100, 200 described above, in step S 4 the behavior of the hydraulic consumer connected to the two hydraulic consumer connections A and B is identified automatically on the basis of a computer-based model structure. In general, for each hydraulic consumer in a hydraulic system to be regulated, the behavior of this hydraulic consumer will be identified automatically on the basis of a dedicated computer-based model structure. If, for example, two hydraulic consumers are present in such a hydraulic system, their behavior will also be identified automatically on the basis of two computer-based model structures. The automated identification of the behavior of the hydraulic system 100, 200 may also be referred to as training the computer-based model structure.In step S 5, system equations of the hydraulic system 100, 200 are automatically extracted from the computer-based model structure. In the present case, a state space model is therefore extracted from the computer-based model structure, for example. This state space model can be, in particular, a non-linear state space model.In step S 6, the electronic controller is synthesized automatically on the basis of the extracted system equations. In the present case, for example, a linear parameter varying (LPV) system is generated from the nonlinear state space model. Jacobi matrices may also be generated from the state space model. The synthesized controller is presently an H-infinity controller. Alternatively, other types of controllers, such as H2, back-locking or model predictive control, can of course also be used.In step S 7, the synthesized electronic controller is embedded in the electronic control unit 12 of the hydraulic system 100, 200 in an automated manner. This means that the once synthesized electronic controller is no longer changed during the ongoing operation of the hydraulic system 100, 200. However, it is naturally possible to repeat the method according to the invention for the automated, measurement data-based design of the electronic controller for the hydraulic system 100, 200 in order to adapt the synthesized electronic controller to changed environmental conditions.As indicated by the dashed line in FIG. 3, the automated steps S 2 to S 7 of the method according to the invention are carried out by the external device 30 in the present case. For this purpose, the external device 30 is connected to the hydraulic system 100, 200 via the data communication interface, and the electronic computing unit 32 performs the automated steps S 2 to S 7.It is of course also possible for the external device 30 to be omitted and the automated steps S 2 to S 7 to be carried out by the electronic control unit 12 of the hydraulic system 100, 200. This is possible in particular when the electronic control unit 12 has sufficient computing power and storage space available for carrying out steps S 2 to S 7. This is often not the case in particular in existing mobile hydraulic systems, which is why it is expedient in this case to offload the computation-intensive steps S 4 to S 6 to the external device 30 in particular.After the electronic controller has been synthesized and embedded in the electronic control unit 12, according to the method according to the invention for controlling at least one controlled variable in the hydraulic system 100, 200, the control of the at least one controlled variable in the hydraulic system 100, 200 is carried out by the synthesized electronic controller (step 8). As already mentioned, for the at least one controlled variable in the hydraulic system 100, 200, conventionally pressures, volume flows, paths or positions are considered. The actuating currents of the electrically actuated valves 10, 20 function as actuating variables in the hydraulic system 100, 200.With the method according to the invention, the device 30 according to the invention and the hydraulic system 100, 200 according to the invention, electronic controllers can be designed and used automatically and on a data basis. As a result, an individually adapted electronic controller can be provided in an automated manner for each hydraulic system 100, 200 and for each control task conceivable for the respective hydraulic system 100, 200, which electronic controller is optimally adapted to the actual conditions in the hydraulic system 100, 200. By removing the computing-intensive method steps from the external device 30, the methods according to the invention can also be used in hydraulic systems in which only little computing power or storage space is available in the electronic control unit 12.REFERENCE NUMERALS10 first electrically actuated valve 12 electronic control unit 14 hydraulic sensor 16 electromagnetic actuating device 18 restoring spring 20 second electrically actuated valve 100, 200 hydraulic system A, B hydraulic consumer connection P pressure source R hydraulic reservoir S 1 to S 8 method steps

Claims

Method for automatically designing an electronic controller for a hydraulic system (100, 200) on the basis of measurement data, the method comprising the following steps: - defining measurement parameters of the hydraulic system (100, 200), - carrying out a predefined measurement routine on the hydraulic system (100, 200), - automatically acquiring measurement data of the measurement parameters of the hydraulic system (100, 200) during the predefined measurement routine, - automatically identifying the behavior of the hydraulic system (100, 200) on the basis of the acquired measurement data on the basis of a computer-based model structure, - automatically extracting system equations of the hydraulic system (100, 200) from the computer-based model structure, - automatically synthesizing the electronic controller on the basis of the extracted system equations, and - automatically embedding the synthesized electronic controller in an electronic control unit (12) of the hydraulic system (100, 200) for controlling at least one controlled variable in the hydraulic system (100, 200).Method according to Claim 1, characterized in that the execution of the predefined measurement routine is automated execution.Method according to one of the preceding claims, characterized in that the computer-based model structure comprises at least one artificial neural network for function approximation.Method according to claim 3, characterized in that the computer-based model structure comprises an ANARX structure, an LSTM structure, an ARMA structure and / or an RNN structure.Method according to one of the preceding claims, characterized in that the synthesized electronic controller is a robust controller.Method according to claim 5, characterised in that the robust regulator is an H-infinity regulator, an H2 regulator, a back-tapping regulator or a model predictive control regulator.Method according to one of the preceding claims, characterized in that the measurement parameters comprise at least one hydraulic parameter of the hydraulic system (100, 200) and at least one actuation current of an electrically actuated valve (10, 20), and the step of automatically acquiring measurement data comprises: - automatically acquiring measurement data of at least one hydraulic sensor (14) of the hydraulic system (100, 200), and - automatically acquiring measurement data of at least one actuation current of an electrically actuated valve (10, 20) of the hydraulic system (100, 200).Method according to Claim 7, characterized in that the at least one hydraulic parameter is a pressure and / or a volume flow and the at least one hydraulic sensor (14) is a pressure sensor and / or a volume flow sensor.Method according to one of Claims 7 or 8, characterized in that the measurement parameters comprise at least one path and / or one position, and the step of automatically acquiring measurement data comprises: - automatically acquiring measurement data of at least one path sensor and / or of one position sensor.Method according to one of the preceding claims, characterized in that the measurement parameters comprise all parameters which are available by measurement technology in the hydraulic system (100, 200).Method according to any one of the preceding claims, characterized in that the automated steps of the method are carried out by an external device (30) connected to the hydraulic system (100, 200) via an electronic data communication interface for this purpose.Method according to one of Claims 1 to 10, characterized in that the automated steps of the method are carried out by the electronic control unit (12) of the hydraulic system (100, 200).Method according to one of the preceding claims, characterized in that the execution of the predefined measurement routine and the acquisition of measurement data are carried out virtually on the basis of a simulation model of the hydraulic system (100, 200).Device (30) for the automated, measurement data-based design of an electronic controller for a hydraulic system (100, 200), wherein the device (30) comprises an electronic data communication interface for establishing a mutual data connection with the hydraulic system (100, 200) and an electronic computing unit (32), and the electronic computing unit (32) is designed to carry out the automated steps of the method according to one of Claims 1 to 11.The apparatus (30) according to claim 14, characterized in that the apparatus (30) comprises the hydraulic system (100, 200).Method for regulating at least one controlled variable in a hydraulic system (100, 200), the method comprising the following steps: - automated, measurement data-based configuring of an electronic regulator for the hydraulic system (100, 200) using the method according to one of Claims 1 to 13, - regulating the at least one controlled variable in the hydraulic system (100, 200) by the synthesized electronic regulator.Method according to Claim 16, characterized in that the at least one controlled variable comprises a pressure, a volume flow, a path and / or a position.Hydraulic system (100, 200) having at least one hydraulic consumer, at least one electrically actuated valve (10, 20) for actuating the at least one hydraulic consumer, at least one hydraulic sensor (14) and an electronic control unit (12), wherein the electronic control unit (12) is designed to carry out the automated steps of the method for controlling at least one controlled variable in the hydraulic system (100, 200) according to one of Claims 16 or 17.Hydraulic system (100, 200) according to claim 18, characterised in that each hydraulic consumer of the hydraulic system (100, 200) is actuated via at least one electrically actuated valve (10, 20) of the hydraulic system (100, 200).Hydraulic system (100, 200) according to one of claims 18 or 19, characterised in that each electrically actuated valve (10, 20) of the hydraulic system (100, 200) is assigned at least one hydraulic sensor (14).

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