Switching device with drive system and method for safely operating a switching device

Abstract

A switching device (1) comprises a switch (17) and a servo drive system (2) for the switch (17). The servo drive system (2) has a motor (14) for driving the on-load tap changer (17), a power component (11) for energizing the motor (12), and a control unit (10) for operating the power component (11) in accordance with at least one setpoint value. The control unit (10) is designed to recognize the presence of at least one safety-relevant event and, if the safety-relevant event is present, to generate and transmit at least one control signal to the power component (11). The power component (11) is designed to introduce or implement at least one safety measure in accordance with the control signal.

Description

Technical Field

[0001] The present invention relates to a switching device having a switch and a drive system for the switch, and a method for safely operating the switching device. Background Technology

[0002] In a substation, there are multiple switches used for different tasks and with different requirements. To operate the corresponding switches, a drive system must be used to operate them. These switches include, in particular, on-load tap changers, load switching switches, selectors, double commutators, commutators, preselectors, power switches, load switches, or circuit breakers.

[0003] Therefore, on-load tap changers are used, for example, for uninterrupted switching between different winding taps of an electrical operating device (such as a power transformer or an adjustable choke). This can, for example, change the transmission ratio of the transformer or the inductance of the choke coil. Dual commutators are used to change the polarity of the windings during power transformer operation.

[0004] All these switches are high-level safety-related components of electrical operating devices because the switching occurs during the operation of the device and is correspondingly connected to the power grid, for example. In extreme cases, disturbances during operation can have serious technical and economic consequences. Summary of the Invention

[0005] Therefore, the objective of this invention is to provide an improved concept for driving switches, particularly on-load tap changers, load switching switches, selectors, double commutators, commutators, preselectors, power switches, load switches, or circuit breakers, thereby improving operational safety.

[0006] The improved concept is based on the idea that the drive system is designed as a servo drive system and equipped with a power component that introduces or implements safety measures in the event of a safety-related incident.

[0007] Typically, safety measures are implemented through a separate safety module (e.g., a contactor with hardwire) located outside the power components.

[0008] According to the improved concept, a switching device is provided, comprising a switch and a servo drive system for the switch. The servo drive system has a motor for driving the switch, a power component for supplying energy to the motor, particularly for controlled or regulated supplying energy to the motor, and a control unit for operating the power component according to at least one rated value. The control unit is designed to identify the presence of at least one safety-related event, and if a safety-related event exists, to generate at least one control signal and transmit it to the power component. The power component is designed to introduce or implement at least one safety measure according to the control signal.

[0009] An electronically adjustable motor drive system is referred to as a servo drive system, wherein the adjustment may include: position, angle, or condition adjustment; speed or rotational speed adjustment; acceleration adjustment; and / or torque adjustment. Therefore, the term "servo drive system" implies that the drive system has means for detecting one or more of the adjusted variables and for feeding back corresponding feedback signals to a control unit, and that the adjustment is performed using these feedback signals.

[0010] Operating the power component according to the at least one rated value is equivalent to regulation in this sense.

[0011] The operational safety of switching devices is improved by introducing safety measures in the event of safety-related incidents.

[0012] According to at least one embodiment, a motor for driving a switch is coupled to the switch shaft or other components via one or more transmission devices.

[0013] According to at least one embodiment, the switch can be configured as an on-load tap changer or load switching switch or selector or double commutator or commutator or preselector or power switch or load switch or circuit breaker.

[0014] According to at least one embodiment, the power component is designed as a converter, especially a servo converter, or as an equivalent electronic unit, especially a fully electronic unit, for driving a machine.

[0015] According to at least one embodiment, the power component is designed to stop the motor, particularly to safely stop it, via a first safety measure among the at least one safety measure. Here, stopping the motor may also include movement within defined tolerances.

[0016] According to at least one embodiment, safely stopping the motor includes a safety function corresponding to the stopping category according to industry standard EN602041:2006, the contents of which are hereby incorporated herein by reference.

[0017] According to at least one embodiment, safely stopping the motor includes a Safe Torque Off (STO) safety function, a Level 1 Safe Stop (SS1) safety function, a Level 2 Safe Stop (SS2) safety function, or a Safe Operation Stop (SOS) safety function.

[0018] According to at least one embodiment, the safety measures include monitoring the movement or position of the motor, particularly the motor shaft.

[0019] According to at least one implementation, monitoring the movement of the motor includes a safety speed limit (SLS) safety function, a safety speed monitoring (SSM) safety function, a safety speed range (SSR) safety function, a safety position limit (SLP) safety function, a safety position (SP) safety function, or a safety direction (SDI) safety function.

[0020] According to at least one embodiment, the first safety measure includes uncontrollably stopping the motor.

[0021] According to at least one embodiment, the power component is designed to completely interrupt the energy supply to the motor based on the control signal. In particular, the first safety measure includes immediately or instantly cutting off the energy supply. Here, the energy supply remains interrupted even when the motor stops operating, so that the motor is no longer able to provide torque (corresponding to STO).

[0022] According to at least one embodiment, the power component is designed to controllably brake or controllably stop the motor based on the control signal. Simultaneously, it maintains the energy supply to the motor.

[0023] According to at least one embodiment, the power component is designed to completely interrupt the energy supply to the motor after controlled braking or stopping operation according to the control signal, so that the motor is no longer able to provide torque (corresponding to SS1).

[0024] According to at least one embodiment, the power component is designed to maintain the energy supply to the motor after controlled braking or stopping operation according to the control signal and to adjust the position of the motor, especially the motor shaft, to a rated position (corresponding to SS2).

[0025] According to at least one embodiment, the power component is designed to introduce additional safety measures, particularly including STO or SS1 safety functions, in the event of a breach of tolerances regarding the rated position.

[0026] According to at least one embodiment, the power component is designed to limit the speed or rotational speed of the motor shaft by a second safety measure among the at least one safety measures.

[0027] According to at least one embodiment, the power component is designed to limit the speed such that the speed is less than or equal to a predetermined maximum speed (corresponding to SLS or SSR).

[0028] According to at least one embodiment, the power component is designed to limit the speed such that the speed is greater than or equal to a predetermined minimum speed (corresponding to SSM or SSR).

[0029] According to at least one embodiment, the power component is designed to introduce additional safety measures when exceeding the maximum speed or falling below the minimum speed, particularly including STO or SS1 safety functions.

[0030] According to at least one embodiment, the at least one safety-related event includes a deviation (corresponding to SDI) in the direction of rotation of a motor, motor shaft, or other shaft of a switching device from a predetermined rated direction of rotation.

[0031] According to at least one embodiment, the rotation direction is detected by an encoder device.

[0032] According to at least one embodiment, the servo drive system has an absolute encoder disposed on the servo drive system or a switch, particularly an on-load tap changer, load switching switch, selector, dual commutator, commutator, preselector, power switch, load switch, or circuit breaker, to detect the absolute position of the motor shaft or another shaft of the switching device. The control unit is designed to generate control signals based on the feedback signal from the absolute encoder.

[0033] According to at least one embodiment, the at least one safety-related event (corresponding to SLP) occurs when the absolute position of the motor shaft or another shaft is lower than a predetermined minimum position or higher than a predetermined maximum position.

[0034] According to the improved concept, a method for safely operating a switching device is also provided. According to the method, the power component of the switching device is operated according to at least one rated value. The existence of at least one safety-related event is identified, and in the event of a safety-related event, at least one control signal is transmitted to the power component. Based on the control signal, at least one safety measure is introduced or implemented through the power component.

[0035] Other design forms and implementations of this method are directly derived from different design forms of the switching device. In particular, one or more components described with respect to the switching device and / or means for implementing the method can be implemented accordingly. Attached Figure Description

[0036] The invention will now be explained in detail with reference to the accompanying drawings and exemplary embodiments. Identical, functionally identical, or effect-equivalent components may be provided with the same reference numerals. Identical or functionally identical components may be explained with reference only to the first drawing in which they appear. Explanations are not necessarily repeated in subsequent drawings.

[0037] In the attached diagram:

[0038] Figure 1 A schematic diagram showing an exemplary embodiment of the switching device according to the improved concept; and

[0039] Figure 2 A schematic diagram illustrating another exemplary embodiment of the switching device according to the improved concept is shown. Detailed Implementation

[0040] Figure 1 A schematic diagram of an exemplary embodiment of a switching device according to the improved concept is shown, comprising a switch 17 and a servo drive system 2 connected to the switch 17 via a drive shaft 16. The servo drive system 2 includes a motor 12 that can drive the drive shaft 16 via a motor shaft 14 and optionally via a transmission 15. A control unit 3 for the servo drive system 2 includes a power component 11 for controlled or regulated energy supply to the motor 12 and a control unit 10 for operating the power component 11, for example via a bus 18. The power component includes, for example, a servo converter.

[0041] The servo drive system 2 may have an encoder system 13, which serves as a feedback system or is part of a feedback system and is connected to the power unit 11. Furthermore, the encoder system 13 is directly or indirectly coupled to the drive shaft 16.

[0042] The encoder system 13 is designed to detect the position of the drive shaft 16, particularly its angular position, such as an absolute angular position, and to generate a feedback signal based thereon. For this purpose, the encoder system 13 may include, for example, an absolute encoder, particularly a multi-turn absolute encoder, fixed to the drive shaft 16, the motor shaft 14, or another shaft whose position is explicitly associated with the absolute position of the drive shaft 16. For example, the position of the drive shaft 16 may be explicitly determined by the position of the motor shaft 14, for example, through the transmission ratio of the transmission 15. The control device 3, particularly the control unit 10 and / or the power component 11, is designed to control or regulate the motor 12 based on the feedback signal.

[0043] The fixing of an absolute encoder can be achieved by implementing a combination of form-locking connections and force-locking or material-locking connections.

[0044] Control unit 10 can identify the presence of safety-related events, such as interference or malfunction of switch 17 or drive system. If a safety-related event exists, control unit 10 transmits a control signal to power component 11, which then introduces or implements safety measures.

[0045] Figure 2 A schematic diagram illustrating another exemplary embodiment of the switching device 1 according to the improved concept is shown, which is based on... Figure 1 The implementation method.

[0046] The switching device 1 may optionally include a switch cabinet 21, inside which a control unit 10, a power unit 11, and an optional human-machine interface 19 are housed. The human-machine interface 19 is connected to the control unit 10 and may be used, for example, for control, maintenance, or configuration purposes.

[0047] The motor 12, motor shaft 14, encoder system 13 and / or transmission device 15 can be installed inside or outside the switch cabinet 21.

[0048] The switching device 1, especially the control unit 10, is coupled to the safety device 20, which includes, for example, a power switch or a circuit breaker, to disconnect the switching device or the electrical operating devices associated with the switching device from the power grid in the event of a fault or interference with the switching device.

[0049] The improved switching device according to the aforementioned concept enhances the operational safety of the servo drive system, switches, and operating devices. This is achieved, in particular, by introducing safety measures via power components.

[0050] Figure Labels

[0051] 1 Switching device

[0052] 2 Servo Drive System

[0053] 3. Control device

[0054] 10 Control Unit

[0055] 11 Power Components

[0056] 12 motors

[0057] 13 Encoder System

[0058] 14 Motor Shaft

[0059] 15. Transmission device

[0060] 16 drive shafts

[0061] 17 Switches

[0062] 18 bus

[0063] 19 Human-Machine Interface

[0064] 20 Safety devices

[0065] 21 Switchgear

Claims

1. Switchgear (1) comprising a switch (17) configured as an on-load tap changer and a servo drive system (2) for the switch (17), the servo drive system (2) comprising: a motor (12) for driving the switch (17); a power component (11) for supplying the motor (12) with energy; and a control unit (10) for manipulating the power component (11) in accordance with at least one setpoint value; wherein: the control unit (10) is designed to identify the presence of at least one safety-relevant event and to transmit at least one control signal to the power component (11) in the event of said safety-relevant event; the power component (11) is designed to - introduce or implement at least one safety measure, - cause the motor (12) to be controlled to brake or to be controlled to stop, - completely interrupt the supply of energy to the motor (12) after said controlled braking or controlled stopping. the power component (11) is designed to cause the motor (12) to stop by means of a first safety measure of said at least one safety measure.

2. The switching device (1) according to claim 1, wherein said first safety measure comprises causing the motor (12) to uncontrolled stop.

3. The switching device (1) according to claim 2, wherein the power component (11) is designed to completely interrupt the supply of energy to the motor (12) in accordance with said control signal.

4. The switching device (1) according to claim 2 or 3, wherein said power component is designed to maintain the supply of energy to the motor (12) after said controlled braking or stopping in accordance with said control signal and to adjust the position of the motor (12) to a setpoint position.

5. The switching device (1) according to claim 1, wherein the power component (11) is designed to limit the speed of a motor shaft (14) of the motor (12) by means of a second safety measure of said at least one safety measure.

6. The switching device (1) according to any one of claims 1 to 3, wherein the power component (11) is designed to limit the speed such that the speed is less than or equal to a predetermined maximum speed.

7. The switching device (1) according to claim 6, wherein the power component (11) is designed to limit the speed such that the speed is greater than or equal to a predetermined minimum speed.

8. The switching device (1) according to claim 6, wherein said at least one safety-relevant event comprises a deviation of the direction of rotation of the motor (12), of a motor shaft (14) of the motor (12) or of a further shaft of the switchgear from a predetermined setpoint direction of rotation.

9. The switching device (1) according to any one of claims 1 to 3, wherein 10. Switchgear (1) according to any one of claims 1 to 3, wherein the servo drive system (2) has an absolute value encoder which is arranged on the servo drive system or on the switch (17) in order to detect the absolute position of a motor shaft (14) of the motor (12) or of a further shaft of the switchgear; and the control unit (10) is designed to generate said control signal in accordance with a feedback signal of said absolute value encoder. said at least one safety-relevant event is present when the absolute position of the motor shaft (14) or of said further shaft is below a predetermined minimum position or exceeds a predetermined maximum position.

11. The switching device (1) according to claim 10, wherein ​ 12. Method for safely operating a switching device (1), wherein The switching device (1) comprises a switch (17) configured as an on-load tap changer and a servo drive system (2) for the switch (17), and the servo drive system (2) comprises a motor (12) for driving the switch (17), a power component (11) for energizing the motor (12), and a control unit (10) for operating the power component (11) in accordance with at least one setpoint value, the method comprising: operating the power component (11) of the switching device (1) in accordance with at least one setpoint value by means of the control unit (10), identifying the presence of at least one safety-relevant event, and transmitting at least one control signal to the power component (11) in the event of said safety-relevant event; introducing or implementing at least one safety measure by means of the power component (11) in accordance with said control signal, causing the motor (12) to be controlled to brake or to be controlled to stop, and completely interrupting the energization of the motor (12) after said controlled braking or controlled stopping.

Images