CN110005598B

CN110005598B - Hydraulic pressure supply mechanism

Info

Publication number: CN110005598B
Application number: CN201811525035.1A
Authority: CN
Inventors: S.施密特
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2017-12-14
Filing date: 2018-12-13
Publication date: 2023-01-13
Anticipated expiration: 2038-12-13
Also published as: DE102017222761A1; CN110005598A

Abstract

The invention relates to a hydraulic supply device for supplying or actuating a hydraulic consumer with a hydraulic pressure medium, comprising a hydraulic pump, an electric motor provided for driving the pump, and a converter provided for actuating the electric motor at a predefinable rotational speed. According to the invention, the converter is provided with an electronic process control, which is set up to: the temporal or event-controlled behavior of the hydraulic pressure and/or of the quantity of pressure medium supplied by the hydraulic pump as a result of the actuation of the electric motor is predefined.

Description

Hydraulic pressure supply mechanism

Technical Field

The present invention relates to a hydraulic supply mechanism for supplying or controlling a hydraulic load.

Background

Conventional feeding devices, also referred to as aircrews, are known. The applicant has provided under the name ABPAC, cytroPac or DFE or Sytronix a hydraulic unit which supplies a hydraulic load with pressure medium or even directly actuates the hydraulic load.

The german patent application DE 10 2015 219 091 A1 of the applicant describes a so-called compact assembly in which the oil reservoir, the electric motor which is controlled in a variable speed manner by means of a converter, and the hydraulic pump form a structural unit. The conveying capacity of the assembly can be controlled by means of the converter.

DE 10 2008 019 501 A1 describes a device which is composed of a variable-speed motor, a pump which can be set with regard to its delivery rate, and a control unit which is assigned to this device. Here, the pressure value and the feed flow rate value of the motor/pump device are predetermined as target values by the control means at the upper stage. A control unit associated with the motor/pump unit controls the flow rate control element of the pump as a function of these predefined target values and controls the rotational speed of the electric motor by means of a so-called rotational speed predefining element. Of course, the delivery flow of the hydraulic pressure to be output and the pressure at the output of the motor/pump unit are always determined by target values that are predefined outside the motor/pump unit. In the control unit associated with the motor/pump unit, an optimization unit for adjusting a predefined target value is operated by means of the control variables of the rotational speed and the delivery rate of the variable displacement pump.

In such assemblies or devices, the desired operating characteristics of the motor/pump device, including the characteristics in the event of a fault, have hitherto been described to a large extent by higher-level control systems and therefore lead to considerable complexity in design and implementation.

Disclosure of Invention

The object of the invention is to make it possible to integrate a hydraulic supply into a production plant or machine more easily.

This object is achieved by a hydraulic supply device.

According to the invention, a hydraulic supply device for supplying or actuating a hydraulic consumer with a hydraulic pressure medium is specified, comprising a hydraulic pump, an electric motor provided for driving the pump, and an inverter provided for actuating the electric motor at a predefinable rotational speed. The converter is provided with an electronic process control, which is designed to: the time-dependent or event-dependent behavior of the hydraulic pressure and/or of the quantity of pressure medium supplied by the hydraulic pump as a result of the actuation of the electric motor is predefined. In this way, a simple and also relatively complex operating process of the hydraulic supply device can be provided in the hydraulic supply device, already pre-configured, and more precisely in the control device of the converter, which is now designed as a process control device according to the invention. The preconfigured pressure and/or delivery flow rate profile, which is also referred to in this application as a pressure/profile/delivery flow rate profile or as a P/Q profile or a P/Q profile and is provided for example as a process program, is intended for the case of a fault or as a reaction to an external influence acting on the hydraulic supply. The end user can trigger these P/Q trends, for example, by means of specific trigger signals, or they can be operated automatically, without the end user having to define and implement the characteristics of the supply means himself for this purpose.

The hydraulic supply means thus equipped can therefore be integrated into a production plant or machine with little design effort and independently perform a preconfigured temporal or event-controlled behavior with regard to the delivery flow or pressure during operation. The effort for designing and adjusting the production plant or machine can therefore be significantly reduced, since the predefined program for the typical process of the hydraulic supply can be used. A simple process can be carried out by the hydraulic supply unit even in stand-alone operation by means of the P/Q course stored in the process control unit.

An example of a procedure for the pre-configuration can be, for example, an emergency operation with a predefined pressure/delivery flow profile, which is executed when the user actuates the emergency stop button. Or a pressure/delivery flow profile, which is provided in the control unit of the converter, can be operated independently of the hydraulic supply unit after a start signal is received from a higher-level control unit. In this case, even boundary conditions, such as the arrival of a specific position of the hydraulic consumer, can be checked and thus the progression of a predefined trend, which has, for example, a pressure value or a delivery flow value, which is predefined in a stepwise manner, from, for example, a first movement phase to a second movement phase, can be controlled. Furthermore, environmental or usage-related boundary conditions can be detected and used for self-control of the hydraulic supply unit or for adjustment of stored processes or for adjustment of external control presets. For example, for cold temperatures of the pressure medium or for increased contamination of the filter, different process sequences can therefore be selected than under standard operating conditions. In this context, for example, the operation of a predetermined ramp for reaching the target value is also taken into account as a process program. The slope of the ramp or the amplitude-time profile of such a ramp can be changed depending on the mentioned external conditions.

Furthermore, a heat engine program can be considered in which the pump first conveys the pressure medium back into the tank with a predetermined delivery quantity via a bypass or via a filter, as well as a reservoir loading program in which the filling level or pressure on the reservoir is measured and a specific pressure and/or delivery flow rate trend is set or set as a result. Furthermore, an emergency operating program as already mentioned can be considered, as well as a process program for the movement of the hydraulic consumer, which emergency operating program and process program are provided in a decentralized manner in a process control of the hydraulic supply device to the converter of the hydraulic supply device.

The process control unit can also take into account the thermal budget of the components of the hydraulic supply unit, i.e. the power components of the converter, the electric motor, the pump, the tank, and, if appropriate, the cooler, and thus adjust the ramp or the delivery volume and the pressure, i.e. the supplied power of the hydraulic supply unit, within a predefined process or starting from externally predefined target values.

Advantageous refinements of the invention are the subject of the preferred embodiments. It is particularly advantageous if the electronic circuit of the converter and the electronic process control are arranged in the same housing, and in particular if the converter has a microcontroller which represents the electronic process control by means of a program which can be executed on it in addition to a conventional converter control module which controls the power components of the converter by means of target value specification. In this way, the resources of the microcontroller which are present per se in accordance with the conventional art are optimally used for the purposes of the invention. The electronic process control unit is preferably designed as a freely programmable process control unit with NC and/or SPS functionality. The temporal or event-controlled process can thus be described and programmed in a simple manner, and the boundary conditions can be checked and the predefined process can be modified as a function of the boundary conditions.

The electronic process control unit preferably has a first interface to the bus system, and in particular a higher-level control unit can be connected via the bus system in order to configure the process control unit and to respond it in a simple manner.

Preferably, a process program for specifying the aforementioned temporal profile is provided in the electronic process control, and the electronic process control is also preferably set up in such a way that the process program itself and/or parameters of the process program can be input and/or read and/or changed via the first interface.

It is also advantageous if the electronic process control unit has a second interface and is set up to: the mentioned process program or a predefined part of the process program is executed after the trigger signal is received on the second interface. The temporal or event-controlled pressure profile and/or delivery flow profile can then be triggered by the user or automatically by a higher-level control unit according to the process program. This second interface, as well as the interfaces described below, can of course be part of the first bus interface. The process of the one-off triggering with the temporal or event-controlled pressure and/or delivery flow rate profile is often no longer monitored at all, but is rather, according to the process program, independently predefined by the process control as a P and/or Q target value or a P/Q target value profile and executed by the converter by means of the converter control module and the power component. Only in the event of a fault, the higher-level control unit receives information from the converter and, if necessary, must perform a protective intervention. An example of a trigger signal generated by the user can be a switching signal of a key by which a process program, for example, for an emergency stop of the hydraulic supply or of the hydraulic consumer is initiated or by which a predefined process program is started, which has a predefined pressure profile/delivery flow profile or a sequence of successively operating, if necessary event-controlled, continuously switched pressure/delivery flow profile phases.

Furthermore, it is preferred that the electronic process control unit has a third interface, which is set up to: receiving a position signal and/or a speed signal from a hydraulic consumer, and the electronic process control unit being designed to: the temporal profile of the mentioned, for example, indicated as a process program is predefined in accordance with predefined regulation or decision criteria taking into account the position signal and/or the speed signal. A further changeover from the first pressure/delivery flow trend phase to the second pressure/delivery flow trend phase can thus be effected, for example, in a process sequence depending on the position of the load. For example, a position-dependent speed reduction of the load can be carried out analogously to a stop buffer, which is facilitated by a corresponding reduction in the delivery flow rate of the hydraulic pump. Alternatively, for example, when the clamping cylinder is actuated, the feed movement, i.e., the removal of the cylinder at a predetermined delivery rate, is converted into a clamping phase with a predetermined pressure. The worker can then specify the end of the clamping phase by means of a key or a higher-level control by means of a trigger, followed by a return movement, i.e. a displacement of the cylinder at a specified delivery rate, until the open position is reached.

Furthermore, it is advantageous if the electronic process control unit has a fourth interface, which is set up for: receiving status signals of the hydraulic pump and/or electric motor and/or inverter, and the electronic process control unit being designed to: the temporal or event-controlled behavior is predefined in accordance with predefined decision criteria taking into account the status signal received at the fourth interface. For example, the acceleration process in the pressure and/or delivery flow profile can be designed to be more gradual, or the slope which is operated to achieve a target value predefined from the higher-level control unit or from the process control unit can be designed to be steeper or less steep. For example, sensors for the temperature of the electric motor, pump, converter can be present, which accordingly generate a status signal and supply it to the fifth interface. The converter itself can generate a signal relating to the thermal load of the motor, which should also be understood as a condition signal. A vibration sensor can be present on the pump, which vibration sensor indicates a cavitation state or can detect the pressure at the suction connection of the pump or at the pressure medium outlet of the pump by means of a sensor and transmits this as a state signal to the fourth interface.

Furthermore, it is preferred that, in the hydraulic supply unit with a tank for hydraulic pressure medium, the following sensors are provided, which are provided to generate status signals of the tank, the hydraulic pressure medium located in the tank, or a cooling or filtering unit associated with the tank, wherein the electronic process control unit has a fifth interface, which is connected to the sensors, and wherein the electronic process control unit is set up to: the temporal or event-controlled behavior is predefined in accordance with predefined decision criteria taking into account the status signal received at the fifth interface. In this way, similar to the situation described in conjunction with the state signals of the hydraulic pump and/or the electric motor and/or the converter, it is possible to operate either an economical pressure and/or delivery flow behavior or a pressure and/or delivery flow behavior which makes full use of the power specification of the hydraulic supply means under nominal conditions. For example, sensors for oil temperature, filling level, gas load in the pressure medium in the container, vibrations, cooler temperature, filter dynamic head, filter contamination level, etc. can be present, which accordingly generate a status signal and supply it to the fifth connection. The signals of these sensors or the sensors mentioned in the preceding paragraph can of course also be used to control a predefined process program or to select and execute specific subroutines of a process program.

All of the aforementioned sensors can of course also be coupled to and communicate with the process control unit via the bus by means of a bus coupler. The corresponding sensor interface is then a component of the bus interface of the process control means.

Drawings

Fig. 1 shows an exemplary embodiment of the hydraulic supply according to the invention.

Detailed Description

According to fig. 1, a hydraulic supply 1, which is designed as a unit or a compact unit or as a controllable pressure medium source, is provided with a hydraulic pump 12, which delivers a pressure medium via a hydraulic line to a hydraulic line 3, which is symbolically represented here by a valve 36, or directly to a hydraulic consumer, to a cylinder 10. Furthermore, the hydraulic supply device can have a reservoir 54, which supplies a pressure medium. The pump 12 is driven by an electric motor 14. The electric motor 14 is supplied with electric current from an inverter 16. For this purpose, the converter 16 is connected to the electric motor 14 by means of a 3-phase ac connection. The converter 16 has a power component 17 and an electronic control unit, which is designed according to the invention as a process control unit 18 or which comprises a module for implementing the process control unit 18.

The electronic control unit 18 is realized primarily by means of a microcontroller 20. The microcontroller 20 has a microprocessor, a memory for data and programs and its own interface. By means of these interfaces, the microcontroller 20 is connected to digital or analog inputs and outputs of the converter, such as, for example, a bus interface 22 and analog or digital sensor connections 30, 31, 32, 33. Furthermore, the microcontroller 20 controls the power component 17 of the converter 16 by means of its interface in order to achieve a predetermined rotational speed or torque of the electric motor 14.

Providing a program or program modules in the microcontroller 20: the converter control module 19' is used to control the power components 17 using the already mentioned target values for rotational speed or torque. A program module can be provided which implements the controller 19 ″ for the variable of the hydraulic pressure. A pressure target value or a delivery flow target value or both of these variables can be predefined for this regulator 19 ″, and the regulator 19 ″ sends a corresponding rotational speed or torque control value to the converter control module 19' for setting the required hydraulic control variable. The actual values required for this purpose are detected by appropriate sensors, for example by the pressure sensor 12 ″ or by the rotational speed sensor 14 ″ or by the displacement sensor 10', and are transmitted to the controller 19 ″.

Furthermore, program modules are present which implement the process control means 18. The process control unit 18 is set up to: a process program is executed, which for example complies with the standard EN 61131-3 or IEC 61131-3 for NC or SPS programs. The process programs can be coded in programming languages such as instruction lists, function block diagrams, sequential function charts and structured text. Furthermore, it is possible to implement an unblocked execution of the free-running task, as described, for example, in application DE 10 2009 055 752 A1, for generating or interpolating the target value trend, in particular as in the case of a motion control. In particular, by means of the process control unit 18 and by means of a process program executed by the process control unit 18, it is intended to be able to map a target value for a predefined rotational speed, a predefined delivery flow or a predefined pressure over a predefined time, a trend and to deliver it to the controller 19 ″ or the converter control module 19'. The pressure and the delivery flow rate preset values are to be fed to the regulator 19 ″ individually or also together as a value pair (P, Q). Alternatively or additionally, it should be possible to trigger a target value trend of the type just described, to output a P/Q trend predefined in the process sequence, to adjust a predefined trend, or to adjust a target value or a target value trend obtained by a superordinate control unit, by means of the flow control unit 18, in case of event control. The term "target value trend" should also include a target value ramp, which is depicted by the process control unit 18 as a result of the target values from the higher-level control unit.

Before the function of the process control unit 18 is discussed in detail, the further elements of the hydraulic circuit in fig. 1 are explained first. As described, the pump 12 delivers pressure medium into a hydraulic circuit, which can comprise a hydraulic reservoir 54 and a multiplicity of hydraulic valves, which are only indicated symbolically by the valve 36. Furthermore, there is a hydraulic load, here a cylinder 10, which is driven by means of a pressure medium delivered by the pump 12. The pressure medium returned by the cylinder 10 can be conducted through a return filter 52 and, if necessary, through a cooler 50 before it is returned to the hydraulic reservoir 40. The converter 16 with its process control unit 18 and its microcontroller 20 are connected to a field bus 24 via a field bus interface 22. Furthermore, a higher-order control unit 26 is present, which can control the converter 16 via the field bus 24. According to this embodiment, different sensors are provided, either simultaneously or as an alternative, which are connected to the respective interfaces 30, 31, 32, 33. Of course, the sensors can also be connected to the field bus 24 by means of a field bus coupler. The just mentioned interfaces 30-33 are then implemented as part of the field interface 22. A suction pressure sensor 12' can be provided on the pump 12, which measures the pressure in the suction connection. Furthermore, a pressure sensor 12 ″ can be present at the output, which pressure sensor measures the pressure of the pressure medium delivered by the pump 12. Furthermore, a temperature sensor 12'″ and a vibration sensor 12' ″ can be attached to the pump. A temperature sensor 14' and a rotational speed sensor 14 ″ can be provided on the electric motor. The power components 17 of the converter 16 can themselves be provided with a temperature sensor (not shown). The cooler 50 can be provided with a temperature sensor 50'. The filter 52 can have a sensor 52' for detecting the degree of contamination of the filter 52. This sensor 52' is capable of measuring the degree of contamination from the dynamic head loaded on the filter 52. The container 40 can be equipped with a temperature sensor 42, a filling level sensor 44 and a sensor 46 for detecting the pressure medium quality. This sensor 46 can be designed, for example, such that it measures the water content or the gas content of a pressure medium, typically mineral oil. A pressure sensor 54', if necessary a fill level sensor or a leak sensor, can be provided on the hydraulic accumulator 54. As already mentioned, the cylinder 10 can be provided with a displacement sensor 10'. A key 38 can also be provided and can be connected to the converter for the purpose of manually generating a trigger signal or a control signal by a user. As mentioned, these sensors, if present, are connected in terms of signals to the inputs 30 to 33 of the converter 16 or the process control unit 18. In fig. 1, this is shown by a connecting line or is outlined by a line ending in a dotted line. The measured values of the sensors can be supplied to the controller 19 ″ as actual values for the respective control variables. The measured values of these sensors can likewise be fed to the process control unit 18 and then used to preset the target values generated by the process control unit 18, or the measured values are used to select a profile of the target values at specific preset times in the process program and are output by the process control unit 18 to the controller 19 ″ or the converter control module 19'. Likewise, the trigger signal generated by the key 38 can be used to select and output a particular temporal profile of the P-, Q-, or (P, Q) -target value in the process program. The measured values of some sensors can also be regarded as status signals which indicate the status of components, such as the power unit 17, the motor 14, the pump 12, the filter 52, the reservoir 54, the container 40 or the pressure medium present therein. Furthermore, measured values for environmental conditions, such as local temperature or vibrations, can be detected and transmitted via the sensors to the converter 16 or the process control unit 18.

Said upper stageThe control unit 26 can predetermine a target value Q for the pressure medium delivery flow to be provided by the hydraulic supply unit 1 for the converter 16 via the field bus 24 _Target Or a target value P for said pressure _Target . In addition, a process program can be entered into the memory of the microcontroller 20 in this way. It is also possible to adjust the process program, select and start, delete or edit portions thereof.

The function of the hydraulic supply unit 1 with the process control unit 18 will be explained below by way of an example.

A program is provided and executed in the microcontroller 20 of the converter 16, which program implements the process control means 18. A first process program for the movement cycle of the hydraulic cylinder 10 is stored in the memory of the microcontroller 20, which first process program has a list of path points and speeds with which these path points should be reached. Furthermore, the hydraulic pressure in the cylinder is predefined for a specific path point. Such a movement cycle can be used, for example, in a hydraulic clamping device.

The user presses the key 38 and thereby generates a trigger signal that is received by the process control mechanism 18 at the interface 30. In response to the trigger signal, the process program is started in the process control means 18. Subsequently, a delivery flow rate target value Q is generated _Target And outputs it to the controller 19 ″, so that the converter control module 19' receives the corresponding speed control value and the pump 12 supplies the cylinder 10 with pressure medium and moves it in the direction of the first path point. In this case, the displacement sensor 10 continuously transmits the current position of the cylinder to the process control unit 18. If the position of the first path point is reached, the process program switches into a second movement phase and generates a delivery flow target value for reaching the second path point in this way, for example, at a reduced speed. If the second path point is reached, in a third phase, for example, a pressure is predefined-a target value P _Target . Subsequently, the controller 19 ″ uses the speed control value to actuate the converter control module 19' in order to set a predefined pressure at the output of the pump 12, measured with the sensor 12 ″ or measured at the hydraulic cylinder 10. After a specific time predefined in the process program or after a continuation signal is received from the higher-level control unit 26, the process program is used to cause the following results: in a fourth phase, a third path point is reached for carrying out the return movement of the cylinder 10, by: in turn, generates a corresponding delivery flow-target value. If the direction of rotation of the pump 12 can be changed, a delivery flow rate target value which is negative for the return movement of the cylinder 10 can be generated. However, a switching signal for a directional valve, for example valve 36, can also be generated by the process control 18 for reversing the direction of movement of the cylinder 10 in the same delivery direction of the pump 12.

A second process program can also be considered, which controls the memory loading. To this end, the fill level signal or the pressure signal at the reservoir 54 with the sensor 54' is detected by the process control unit 18 and evaluated by the process program. In principle, such a process program can predetermine the desired reservoir loading pressure. Such a process sequence can additionally specify a delivery flow rate characteristic curve by means of which the desired reservoir loading pressure is reached optimally, i.e., for example, as efficiently as possible or as quickly as possible or as material-saving as possible, in particular without overshooting in the actual pressure value.

A possible third process program can control the characteristics after the actuation of the emergency stop key comparable to said key 38. Such a process program can provide that a predetermined pressure is provided by the pump 12 at a specific time and then the pressure preset and the delivery flow preset are set to 0. Furthermore, the power component 17 can be switched off thereafter.

Possible fourth processThe sequence enables the control of the characteristics of the hydraulic feed mechanism 1 under specific environmental conditions. Thus, for example, the slope of the pressure target value ramp or the delivery flow rate target value ramp can be adjusted as a function of the measured temperature or as a function of the measured oscillation or when the intake pressure is too low. In this case, P can be predetermined for the pressure-target value of the higher-level control means 26 _Target Or delivery flow-target value is given by Q _Target Or the ramp may be generated by the process control mechanism 18 for a target value generated by another process routine of the process control mechanism 18. A possible fifth process sequence can control or adjust the properties of the hydraulic supply unit as a function of the state of the components of the hydraulic supply unit 1, including the pressure medium, or as a function of the state of further components of the hydraulic circuit. Therefore, Q can be predetermined in accordance with the filter contamination signal of the filter 52 or a reduction in the delivery flow rate when the oil level in the container 40 is low _Target Is the maximum allowable value of. The target delivery flow Q can also be set, in particular lowered, as a function of the temperature at the cooler 50 _Target . The increased temperature of the pressure medium in the reservoir 40 on the motor 14, on the pump 12, can also be used for predetermining the delivery flow rate target value and/or the pressure target value P _Target Is used as an incentive to make adjustments. The corresponding sub-routine in the process program then limits the target values obtained from the higher-level control unit 26 or from other process programs according to the maximum value specification. The converter control module 19' can also calculate the thermal load of the electric motor 14 on the basis of a physical model and reduce or limit the predefined setpoint value of the hydraulic variable, i.e. the pressure or the delivery flow, when a thermal load limit value is reached or approached. If the sensor 46 detects an increased gas load or an increased water content in the pressure medium, this process sequence can also switch on a degassing device or a dewatering device (not shown), and limit the pressure target value or the delivery flow target value during this time。

A hydraulic supply device for supplying or actuating a hydraulic consumer with a hydraulic pressure medium comprises a hydraulic pump, an electric motor provided for driving the pump, and an inverter provided for actuating the electric motor at a predefinable rotational speed. According to the invention, the converter is provided with an electronic process control, which is designed to: the temporal or event-controlled behavior of the hydraulic pressure and/or the quantity of pressure medium supplied by the hydraulic pump as a result of the actuation of the electric motor is predefined.

In this way, an easy and also complicated operating process of the hydraulic supply device can be provided in the hydraulic supply device, already pre-configured, and more precisely in the control device of the converter, which is now designed as a process control device according to the invention. The expenditure for designing and adjusting the device or machine can therefore be significantly reduced, since a predefined program for a typical process of the hydraulic supply can be used. A simple process of loading in the machine can be carried out by the hydraulic supply even in stand-alone operation.

List of reference numbers:

1. hydraulic pressure supply mechanism

3. Hydraulic circuit

10. Hydraulic load

10' displacement sensor on said hydraulic load

12. Pump

12' suction pressure sensor

12'' output pressure sensor

12' ' ' temperature sensor

12'' '' vibration sensor

14. Electric motor

14' temperature sensor

14'' rotation speed sensor

16. Current transformer

17. Power component

18. Process control mechanism

19' converter control module

19' regulator module

20. Micro-controller

22. Bus interface

24. Fieldbus

26. Control mechanism of upper stage

30. Interface of trigger

31. Interface of cylinder displacement sensor

32. Interface for status signals of a motor or a pump

33. Interface of a status signal and a further signal of a container

36. Valve with a valve body

38. Electric key

40. Container with a lid

42. Temperature sensor

44. Fill level sensor

46. Pressure medium mass sensor

50. Cooling mechanism

50' temperature sensor

52. Filter

52' pollution sensor and dynamic pressure sensor

54. Pressure medium reservoir

54' pressure medium reservoir.

Claims

1. A hydraulic supply device for supplying or actuating a hydraulic consumer (10) with a hydraulic pressure medium, comprising a hydraulic pump (12), an electric motor (14) provided for driving the hydraulic pump (12), and a converter (16) provided for actuating the electric motor (14) at a predefinable rotational speed,

it is characterized in that the preparation method is characterized in that,

the converter (16) is provided with an electronic process control unit (18) which is designed to: a temporal or event-controlled behavior of the hydraulic pressure and/or of the quantity of pressure medium supplied by the hydraulic pump (12) as a result of the actuation of the electric motor (14) is specified.

2. The hydraulic supply device as claimed in claim 1, characterized in that the electronic circuit (17, 19', 19 ") of the converter (16) and the electronic process control device (18) are arranged in the same housing.

3. The hydraulic supply device as claimed in claim 1 or 2, characterized in that the converter (16) has a microcontroller (20) which represents the electronic process control device (18) by means of a program which can be executed thereon.

4. Hydraulic supply device according to claim 1 or 2, characterised in that the electronic process control device (18) is designed as a freely programmable process control device with NC and/or SPS functionality.

5. The hydraulic supply device according to claim 1 or 2, characterized in that the electronic process control device (18) has a first connection (22) to a bus system (24) and can be connected to a higher-level control device (26) via the bus system (24).

6. The hydraulic supply device as claimed in claim 5, characterized in that a predetermined process program for the aforementioned temporal profile is provided in the electronic process control device (18), and the electronic process control device (18) is designed in such a way that the process program itself and/or parameters of the process program can be input and/or read out and/or changed via the first interface (22).

7. The hydraulic supply according to claim 6, characterized in that the electronic process control unit (18) has a second connection (30), and in that the electronic process control unit (18) is designed to: the mentioned process program or a predefined part of the process program is executed after a trigger signal is received at the second interface (30).

8. The hydraulic supply according to claim 1 or 2, characterized in that the electronic process control unit (18) has a third connection (31) which is designed to: receiving a position signal and/or a speed signal from the hydraulic consumer (10), and the electronic process control unit (18) being designed to: the mentioned temporal or event-controlled behavior is predefined in accordance with predefined regulation or decision criteria taking into account the position and/or speed signals.

9. The hydraulic supply according to claim 1 or 2, characterized in that the electronic process control unit (18) has a fourth interface (32) which is designed to: receiving status signals of the hydraulic pump and/or electric motor and/or inverter, and the electronic process control unit being designed to: the temporal or event-controlled behavior is predefined according to predefined decision criteria taking into account the status signal received at the fourth interface (32).

10. The hydraulic supply unit as claimed in claim 1 or 2, further comprising a reservoir (40) for a hydraulic pressure medium, which is connected to a suction connection of the hydraulic pump (12), characterized in that a sensor (42, 44, 46, 50', 52') is provided for generating a status signal of the reservoir (40), of the hydraulic pressure medium present in the reservoir (40) or of a cooling device (50) or a filter device (52) associated with the reservoir (40), in that the electronic process control unit (18) has a fifth interface (33), which is connected to the sensor (42, 44, 46, 50', 52'), and in that the electronic process control unit (18) is designed to: the temporal or event-controlled behavior is predefined according to predefined decision criteria taking into account the status signal received at the fifth interface (33).