Control unit with integrated energy processing and integrated energy management

Abstract

A control unit (1) with integrated energy conditioning and integrated energy management for controlling an electrically operated and / or controlled actuator (2) is proposed, comprising: a controller unit (4) for generating a control signal for the actuator (2); a connection (AC) for connecting the control unit (1) to an external electrical power supply providing a mains voltage (VAC0); a circuit arrangement (8) for conditioning, rectifying, and converting the mains voltage (VAC0) into a first DC link voltage (VCC1), wherein the level of the first DC link voltage (VCC1) is independent of the level of the mains voltage (VAC0);at least one electrical intermediate storage device (7) for the first DC link voltage (VCC1) to buffer a necessary power for maintaining at least one further voltage derived from the first DC link voltage (VCC2, VCC3) to supply the controller unit (4) in the event of failure of the external electrical power supply and for transferring the actuator (2) into a safe state, for example in the event of failure of the external electrical power supply.

Description

[0001] The invention relates to a control unit with integrated energy processing and integrated energy management for controlling an electrically operated and / or controlled actuator.

[0002] The applicant's products, which are typically hydraulically or pneumatically operated, enable the clamping, securing, braking, holding, fixing, and even emergency braking of axially moving loads throughout the entire field of mechanical engineering. There is growing market demand not only to electrify these products and safety concepts, but also to equip them with additional functions and interfaces or to digitize them. The electrification of existing products and the corresponding development of additional (innovative) products is intended to be enabled, among other things, by the development outlined in this patent application.

[0003] The following terms can be listed (as examples) to illustrate the necessity of the desired product electrification: Industry 4.0, condition monitoring (predictive maintenance), communication and data exchange, miniaturization, costs of current actuators and media generation (compressed air, hydraulic pressure) as well as the service life of corresponding moving cables, decentralized systems and higher-level control.

[0004] The present invention addresses a core problem of electrical products, namely the safe and transparent control of actuators used therein, e.g. solenoids, independent of the supply input voltage and possible power failures.

[0005] EP 2 845 072 B1 discloses a so-called compact control unit designed for the fail-safe control of an electrical actuator. However, it disadvantageously lacks consideration of energy management, specifically the system behavior in the event of a power or energy failure, as well as consideration of the shutdown behavior.

[0006] Safe switching off is desirable as a combination of "the switching off itself" and the "time until a safe state is reached" of a connected actuator (hereinafter also referred to synonymously as actuator technology). The cited prior art does not address the need for a (passive) short-circuit path to more quickly dissipate the electrical power stored in an actuator (magnetic field, induction), nor any other type of active demagnetization of the actuator to enable switching off and transferring a clamping unit to a safe (clamped) state. In the cited prior art, energy dissipation in the actuator technology occurs only via heat or power loss, which makes the switching behavior in the event of a fault too slow, especially for safety-relevant applications.

[0007] The invention is based on the object of specifying a control device which overcomes the above-mentioned disadvantages and, in particular, takes into account the system behavior in the event of a power or energy failure and enables a safe switch-off behavior.

[0008] The object is achieved according to the invention by a control device having the features of claim 1. Advantageous further developments are defined in the subclaims.

[0009] A control unit according to the invention with integrated energy conditioning and integrated energy management for controlling an electrically operated and / or controlled actuator comprises a controller unit (microcontroller) for generating a control signal for the actuator. It further comprises a connection for connecting the control unit to an external electrical power supply that provides a mains voltage. Also present is a circuit arrangement for conditioning, rectifying, and converting the mains voltage into a first intermediate circuit DC voltage, wherein the level of the first intermediate circuit DC voltage is independent of the level of the (external) mains voltage.Furthermore, the control unit comprises at least one electrical buffer for the first intermediate circuit DC voltage for buffering a necessary power for maintaining at least one further voltage derived from the first intermediate circuit DC voltage for supplying the controller unit in the event of failure of the external electrical power supply and for transferring the actuator to a safe state, for example in the event of failures of the external electrical power supply.

[0010] According to the invention, the control unit integrates an energy management concept that makes it possible to carry out safety-relevant functions (e.g. switching operations) at any time, especially in the event of a power failure at the power input of the control unit, without being affected by these events, and to transfer connected safety components (e.g. brakes or clamping units) highly dynamically, ie relatively quickly, into their safe state (braked or clamped).

[0011] The energy management concept further decouples the incoming voltage from the supply voltage of an actuator connected or to be connected to the control unit using the aforementioned circuit arrangement, which can, in particular, include an interposed PFC (Power Factor Correction) unit (PFC for short). This decouples globally or country-specific voltage supplies (e.g., 110 V or 230 V) from the actuator voltage supply, eliminating any incorrect activation due to such different mains voltages. This actively prevents a faulty power supply to the system (in the event of the product being switched on in another country with a different mains voltage). The control unit can therefore be used and replaced worldwide without modifications or parameterization.

[0012] The system architecture described here for the construction of fail-safe controllers or control units preferably includes the inclusion of an energy management system with energy conditioning, associated measurement technology and intermediate storage.

[0013] In particular, the integration of energy processing and energy management preferably includes the detection of AC power or voltage failures (power failure) by providing an appropriate sensor device.

[0014] The energy conditioning preferably includes conditioning the supply voltage (mains voltage; alternating current / alternating voltage) to a relatively high DC supply voltage level for controlling the safety components (i.e., the actuators). Higher voltages advantageously enable faster charging and discharging processes in the actuators.

[0015] In general, higher voltages allow faster switching cycles and therefore a so-called high-speed switching behavior, which can be particularly advantageous for safety-relevant applications.

[0016] Preferably, this relatively high DC supply voltage is temporarily stored in a downstream buffer.

[0017] This buffering ensures, in particular, a smoothing of the actuator voltage, i.e., the aforementioned relatively high DC supply voltage. It also provides buffering for the processed power.

[0018] Through network monitoring and the aforementioned buffering, the entire system can be controlled and actively shut down if a power failure or voltage outage is detected on the network side. Essential parameters can be properly stored in the microcontroller, with the last active state being retained in the information system.

[0019] The microcontroller can also preferably actively communicate feedback about the power failure to a higher-level controller (PLC / SPS).

[0020] Preferably, it is further provided that a lower voltage, preferably a 24 V voltage, is derived from the relatively high DC supply voltage.

[0021] Additionally, the aforementioned lower voltage can be read via external connections of the control unit by a higher-level controller (e.g., a PLC), which may be connected to the control unit. This preferably provides feedback to the PLC indicating that the power conditioning in the control unit is functioning.

[0022] The lower voltage can also be provided simultaneously as an external supply via external connections of the control unit.

[0023] A possible external supply to the control unit with the lower voltage as input preferably operates in parallel, meaning it can be connected simultaneously (redundantly). This allows the low voltage to be decoupled from the availability of the mains voltage.

[0024] Furthermore, at least one even lower voltage (e.g., 5 V, possibly 3.3 V) can be derived from the lower voltage. This even lower voltage is preferably used to supply the controller unit (microcontroller) and any logic components present in the controller unit.

[0025] The following embodiments of the control device according to the invention have proven to be particularly advantageous: In one embodiment of the control device according to the invention, the circuit arrangement for conditioning, rectifying and converting the mains voltage comprises a power factor correction filter in the form of a boost converter or a PFC input stage.

[0026] The power factor correction filter advantageously ensures an increased active power component (compared to a reactive power component).

[0027] In one embodiment of the control device according to the invention, the first intermediate circuit DC voltage can in principle be set arbitrarily and independently of a value of the mains voltage, preferably to a value greater than a peak value of the mains voltage, in particular to a value greater than the peak value of a 230 V mains voltage.

[0028] The advantages of such increased voltage have already been mentioned above.

[0029] In one embodiment of the control device according to the invention, it is provided that a size of the buffer for the first intermediate circuit DC voltage in relation to a power buffered or bufferable therein corresponds at least to a power that an actuator that can be connected to the control device in a permissible manner requires at most for transferring to a safe end position (ie to a safe state).

[0030] It can be particularly advantageous if the size of the buffer for the first intermediate circuit DC voltage is selected such that safe shutdown of the largest actuator that can still be connected to the control unit according to the control unit's data sheet is reliably ensured. This means that the size of the buffer, in terms of the power stored therein, corresponds at least to the maximum power required by an actuator that can be connected to the control unit according to the data sheet for safe shutdown, i.e., moving it into a permanently maintainable position (e.g., clamped or braked).

[0031] In one embodiment of the control unit according to the invention, the at least one further derived voltage is derived from the first intermediate circuit DC voltage, wherein the at least one further derived voltage and optionally additional derived voltages provide a sequential energy supply in order to supply one or more further components of the control unit, namely at least the controller unit and / or internal and external communication interfaces, with electrical power.

[0032] The advantages of such a design have already been mentioned above. In particular, it enables at least temporary continued operation of all or at least some components, independent of the state of an external power supply (mains voltage).

[0033] In one embodiment of the control device according to the invention, the at least one further derived voltage and optionally additionally derived voltages are smaller in magnitude than the first intermediate circuit DC voltage, wherein preferably the mains voltage is 110-230 V AC (alternating voltage), the intermediate circuit DC voltage is 380 V DC, the at least one further derived voltage is 24 V DC and the optionally additionally derived voltages are 5 V DC or 3.3 V DC.

[0034] These values ​​have proven particularly advantageous in practice and according to studies conducted by the applicant, especially in the context of safety-relevant applications, e.g. for brakes or clamping units.

[0035] In one embodiment of the control device according to the invention, the at least one further derived voltage or optionally additional derived voltages are DC voltages, while the mains voltage is preferably an AC voltage.

[0036] This has already been pointed out above.

[0037] In one embodiment of the control unit according to the invention, the control unit has at least one external connection, wherein the at least one further derived voltage or at least one optionally additionally derived voltage is applied to the external connection of the control unit.

[0038] This is used to detect this voltage by an external, higher-level control (in particular as a type of status signal indicating that the power supply and processing in the control unit is functioning correctly).

[0039] Alternatively, the external connection is used to supply electrical power to external components, e.g. external sensors (especially position sensors for the actuator).

[0040] Alternatively, the external connection can serve as an external voltage input to supply the control unit with this voltage externally, e.g., via a higher-level control unit (PLC). This voltage can then be converted within the control unit to supply specific components of the control unit.

[0041] This functionality enables particularly flexible use of the control unit.

[0042] In one embodiment of the control device according to the invention, the controller unit is supplied or can be supplied in terms of power by the at least one further derived voltage or by an optionally additionally derived voltage or, with a corresponding embodiment, by an external supply at the external connection, if appropriate after prior conversion of an externally provided voltage, as already mentioned above.

[0043] This functionality also enables particularly flexible use of the control unit.

[0044] In one embodiment of the control device according to the invention, it has at least one sensor means for detecting the mains voltage and for detecting failures of the external electrical power supply and for transmitting corresponding signals to the controller unit so that the controller unit can initiate or cause a safe shutdown, as explained above.

[0045] Further features and advantages of the invention will become apparent from the following description of embodiments with reference to the drawings.

[0046] The only Fig. 1 shows a possible embodiment of the control device according to the invention.

[0047] In the Fig. 1, reference numeral 1 denotes the control unit according to the invention. Reference numeral 2 denotes an actuator connected to the control unit (in this case, an electric motor). Reference numeral 3 represents a higher-level control unit in the form of a PLC. Reference numerals A to O represent inputs / outputs (or corresponding connections) of the control unit 1; the corresponding arrows symbolize input or output signals (depending on the direction of the arrow). Reference numeral 4 denotes a microcontroller (µC), and reference numeral 5 represents a PFC, i.e., a power factor correction filter in the form of a boost converter or a PFC input stage.

[0048] A mains voltage is applied to the PFC 5 (between N and L1 or at terminals B and C), which is, without limitation, 230 V alternating voltage (AC), referred to herein as VAC0. The terminals at least at B and C thus represent a connection for connecting the control unit 1 to an external electrical power supply that provides a mains voltage. A sensor means 6 in the form of a voltmeter is connected between the terminals B, C and parallel to the PFC 5, which measures or monitors the mains voltage. A corresponding measurement / monitoring signal S1 is provided to the microcontroller 4 for further use, e.g., condition monitoring or error analysis (dashed arrow in Fig. 1). The microcontroller 4 can, in turn, generate a corresponding signal S2 and provide it at terminal M for use by the PLC / SPS 3.

[0049] The PFC 5 generates from the mains voltage VAC0 a (in terms of amount, especially related to a peak value VAC0^ the mains voltage VAC0) higher (DC) voltage VCC1 of e.g. 380 V, here referred to as the first intermediate circuit DC voltage VCC1. For this purpose, the mains voltage VAC0 is conditioned, rectified, converted and converted into the first intermediate circuit DC voltage, ie the already mentioned voltage VCC1,VCC1>>VAC0^, , whereby the level of the first intermediate circuit DC voltage VCC1 is preferably independent of the level of the (external) mains voltage. As is well known, the following applies: VAC0=VAC0^2.

[0050] Behind the PFC 5 and parallel to it is an electrical buffer in the form of a capacitor 7, which will be discussed in more detail below.

[0051] Downstream of the capacitor 7 are further components of a circuit arrangement 8. This circuit arrangement 8 comprises, in the present case and without limitation, in addition to the PFC 5 and downstream of the capacitor 7, two DC / DC voltage converters 8a, 8b, which successively derive and provide (DC) voltages VCC2 and VCC3 from the first intermediate circuit DC voltage VCC1, as shown. Without limitation, VCC1 = 380 V DC, VCC2 is 24 V DC, and VCC3 is 5 V DC. Further voltages can also be provided (derived) through appropriate further development, e.g., 3.3 V DC. GND stands for the ground potential. The voltage VCC1 is also referred to here as the first intermediate circuit DC voltage, as already mentioned.

[0052] The voltage or intermediate circuit DC voltage VCC1 is according to Fig. 1 to a safety circuit 9, which is described in a parallel patent application of the applicant, and is provided via this to the terminals J and K for operating the actuator 2. Preferably, the safety circuit 9 is configured to change the polarity of the voltage at the output J / K to the actuator 2, which enables advantageous high-speed control.

[0053] The voltage VCC2 is output, among other things, at terminal O. However, this terminal can also advantageously be used to provide a corresponding voltage externally for the control unit 1, e.g., via the PLC 3. Terminal N is connected to ground potential GND. A voltage VCC2 provided externally at N, O can be converted by the converter 8b to the voltage VCC3 before being used, for example, to supply the microcontroller 4.

[0054] Voltage VCC2 also supplies two position sensors 10, 11 ("Sensor 1", "Sensor 2"), which are designed to detect a position of actuator 2, via terminals H1 and H2 (ground potential GND at I1 and I2). Signals supplied by position sensors 10, 11 are applied at D and F for use by microcontroller 4, and they are provided (after appropriate duplication) at E and G for PLC 3.

[0055] In the present embodiment, the voltage VCC3 is used specifically to supply the microcontroller 4, as already mentioned.

[0056] The electrical buffer (capacitor) 7 for the first intermediate circuit DC voltage VCC1 serves to buffer a necessary power for maintaining at least the voltage derived from the first intermediate circuit DC voltage VCC1, here specifically the voltage VCC3 for supplying the microcontroller 4 in the event of failure of the external electrical power supply and for transferring the actuator 2 into a safe state, for example in the event of failures of the external electrical power supply.

[0057] Terminals A and L are used to connect protective conductors for the safe detection and discharge of any fault currents. The external terminal Q can be used to supply electrical power to at least microcontroller 4 and / or corresponding communication interfaces.

[0058] Through the Fig. In the arrangement shown in Figure 1, the supply voltage (mains voltage) at terminals B and C is first converted to VCC1. In other words, the AC supply voltage at terminals AC or B and C is transformed by the PFC 5 into a DC voltage with VCC1. VCC1>>VAC0^ Higher, mains-voltage-independent voltages VCC1 are available for safety-relevant actuators (e.g., actuator 2). The PFC 5 preferably processes all common mains voltages between 100 V and 230 V or 240 V. VAC0 denotes the mains voltage, for example, 230 V. In electrical engineering terms, this is an "effective value." The peak value is larger and, in the example mentioned, amounts to 230V⋅2=230V⋅1.414≈325V. This peak value is the one we will compare with here. Peak values ​​are usually indicated in the literature with a "roof" above the corresponding symbol: VAC0^=VAC0⋅2=230V⋅1.414≈325V,VCC1>>VAC0^

[0059] The N and O terminals function either as inputs or outputs for the derived voltage VCC2. The derived or conditioned voltage VCC2 is output, for example, to a higher-level controller (PLC / SPS 3) for monitoring. Furthermore, these terminals serve as inputs or as an information source for the PLC / SPS 3 to determine whether the power conditioning in control unit 1 is functioning correctly.

[0060] In particular, the higher-level PLC / SPS 3 can itself provide the voltage VCC2 of, for example, 24 V and thus "overwrite" the 24 V generated in the control unit 1 itself in order to independently supply the control unit 1 with the relevant voltage of 24 V. This enables the VCC2 voltage to be decoupled from the availability of a mains voltage. The microcontroller 4 continues to operate on the logic side even in the event of a power failure at the AC connections, as long as the PLC / SPS 3 provides the required voltage. The sensors, in particular the position sensors 10 and 11 and the mains voltage sensors 6, also continue to operate fully and continue to provide status information about the state of the actuator 2 or in particular a clamping system (or another connected system that includes the actuator 2) and the mains voltage.

[0061] The described derivation of a 24 V voltage VCC2 from the intermediate circuit DC voltage VCC1 shows the advantage of a sequential power supply behind the PFC 5 and the energy storage device (intermediate storage or capacitor) 7: A power failure can be detected by sensors (sensor means 6) and reported to the microcontroller 4. If the power supply fails, at least the voltages VCC2 and VCC3 are generated via the power in the energy storage device 7, so that the µC 4 and the entire logic / sensor system (e.g., the position sensors 10 and 11) continue to be supplied with voltage. The µC 4 thus continues to operate unaffected despite the power failure for a certain time t (t > 0). During this time t, the actuator 2 and, accordingly, a clamping system or the like operated by it can thus be controlled and powered with equivalent power (i.e., with the nominally required power, ie(without compromising functionality), which corresponds to a transition to a safe state, e.g. "clamped". During this time t, status messages are also generated and output (at output M) to or for the higher-level controller (PLC 3) in a preferably controlled manner. During this time t, system-relevant information is also preferably saved in a non-volatile memory area (EEPROM) of the µC 4 so that it is available after the power supply is restored. This memory area is defined in . Fig. 1 is designated by reference numeral 4a. It can, without limitation, also be formed separately from the µC 4 or even from the control unit 1.

[0062] The described integration of controlled, fast (high-speed) switching behavior enables short switching cycles via the high voltage supply provided by the PFC 5 with VCC1 ≥ 380 V, which is (far) above the peak voltages VAC0^ the (worldwide) supply voltages VAC0 of 110 V or 230 V. High voltages ensure rapid charging and discharging of the actuators and thus short response times (safety for humans and machines).

[0063] When actuator 2 is switched off, the polarity of the voltage can be reversed. This allows a magnetic field regularly present in the actuator to be dissipated as quickly as possible, in order to transfer actuator 2 or a clamping element or the like moved by it into a safe (clamped) state. Generally, this enables bilateral overexcitation of the actuator (actuator 2 or a safety component) by a semiconductor relay 9a, preferably present in the safety circuit 9, both when releasing and releasing the actuator.

[0064] The described high-speed shutdown behavior is possible in this case even in the event of a power failure due to the intermediate energy storage in capacitor 7. The power failure is detected by sensors (here, sensor 6). When a power failure is detected, sufficient power is available in capacitor 7 at PFC level (e.g., at 380 V) that actuator 2 or a connected safety component can be transferred to its safe state in a controlled manner, at full power and full speed. In this way, the connected safety component never "sees" a power failure. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2 845 072 B1

[0005]

Claims

[1] Control unit (1) with integrated energy processing and integrated energy management for controlling an electrically operated and / or controlled actuator (2), comprising: a controller unit (4) for generating a control signal for the actuator (2); a connection (AC) for connecting the control unit (1) to an external electrical power supply which provides a mains voltage (VAC0); a circuit arrangement (8) for conditioning, rectifying and converting the mains voltage (VAC0) into a first intermediate circuit DC voltage (VCC1), wherein a level of the first intermediate circuit DC voltage (VCC1) is independent of a level of the mains voltage (VAC0); at least one electrical buffer (7) for the first intermediate circuit DC voltage (VCC1) for buffering a necessary power for maintaining at least one further voltage (VCC2, VCC3) derived from the first intermediate circuit DC voltage for supplying the controller unit (4) in the event of failure of the external electrical energy supply and for transferring the actuator (2) to a safe state, for example in the event of failures of the external electrical energy supply. [2] Control device (1) according to claim 1, wherein the circuit arrangement (8) for conditioning, rectifying and converting the mains voltage comprises a power factor correction filter in the form of a boost converter or a PFC input stage (5). [3] Control device (1) according to claim 1 or 2, in which the first intermediate circuit DC voltage (VCC1) can be set in principle as desired and independently of a value of the mains voltage (VAC0), preferably to a value greater than a peak value VAC0^ the mains voltage (VAC0), in particular to a value greater than the peak value VAC0^ a 230 V mains voltage (VAC0). [4] Control unit (1) according to one of claims 1 to 3, wherein a size of the buffer (7) for the first intermediate circuit DC voltage (VCC1) in relation to a power buffered or bufferable therein corresponds at least to a power that an actuator (2) that can be legally connected to the control unit (1) requires at most for a transfer to a safe end position. [5] Control unit (1) according to one of claims 1 to 4, wherein the at least one further derived voltage (VCC2, VCC3) is derived from the first intermediate circuit DC voltage (VCC1), wherein the at least one further derived voltage (VCC2) and optionally additional derived voltages (VCC3) provide a sequential energy supply in order to supply one or more further components of the control unit (1), namely at least the controller unit (4) and / or internal and external communication interfaces, with electrical power. [6] Control device (1) according to one of claims 1 to 5, in which the at least one further derived voltage (VCC2) and optionally additionally derived voltages (VCC3) are smaller in magnitude than the first intermediate circuit DC voltage (VCC1), wherein preferably the mains voltage is 110-230 V AC, the intermediate circuit DC voltage (VCC1) is 380 V DC, the at least one further derived voltage (VCC2) is 24 V DC and the optionally additionally derived voltages (VCC3) are 5 V DC and 3.3 V DC. [7] Control device (1) according to one of claims 1 to 6, wherein the at least one further derived voltage (VCC2) and optionally additional derived voltages (VCC3) are DC voltages, while the mains voltage (VAC0) is preferably an AC voltage. [8] Control device (1) according to one of claims 1 to 7, with at least one external connection (N, O), in which the at least one further derived voltage (VCC2) or at least one optionally additionally derived voltage (VCC2) is applied to the external terminal (N, O) for detecting this voltage by an external, higher-level control (3) or for supplying electrical energy to external components, e.g. external sensor means (10, 11); or in which the external connection (N, O) serves as an external voltage input for the external supply of the control unit (1) with this voltage (VCC2). [9] Control device (1) according to one of claims 1 to 8, in which the controller unit (4) is or can be supplied with power by the at least one further derived voltage or by an optionally additionally derived voltage (VCC3) or, with reference to claim 8, by external supply at the external terminal (N, O). [10] Control device (1) according to one of claims 1 to 9 with at least one sensor means (6) for detecting the mains voltage (VAC0) and for detecting failures of the external electrical power supply and for transmitting corresponding signals (S1) to the controller unit (4).

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