ARRANGEMENT AND METHOD FOR AN AUTOMATIC CONFIGURATION OF A MAGNETIC DRIVE

Description

[0001] The invention relates to an arrangement for an automatic configuration of a magnetic drive according to the preamble of claim 1 and a method for an automatic configuration of a magnetic drive according to the preamble of claim 8.

[0002] The operating instructions "3TM Vacuum Contactor 7.2 kV - 15 kV, 3-pole, 4.15 kV - 6.9 kV, 1-pole", Order No.: 9229 0106 100 0, Siemens AG 2020, describe a medium-voltage switching device that features a vacuum switching device with an electromagnetic actuator. The magnetic actuator can exert a magnetic force on a so-called armature plate and attract it. The movement of the armature plate is mechanically translated into a movement for pressing the movable contact against the fixed contact within the vacuum switching device. As with magnetic actuators in switches and contactors, this device often uses two magnetic coils, which, depending on the input voltage, must be connected either in parallel (e.g., for AC / DC in countries with 115 V mains voltage) or in series (e.g., for AC / DC in countries with 230 V mains voltage).Even if the customer's nominal line voltage is known, the choice of power supply for the contactor (AC, DC, nominal voltage) is often not yet decided in the early stages of system planning. The customer often only makes a power supply selection once the total power requirements of all system components are known and the control devices for controlling the contactors have been selected.

[0003] When wiring the coils, the correct polarity of the coil connections must be observed. As shown on pages 27 and 28 of the operating instructions, the control electronics contains four connectors (X5, X6, X7, and X8), each with two plugs, into which the 2 x 2 coil connections must be plugged. This means there are a total of 24 different connection options, of which only 12 (parallel or serial) are correctly wired. Manual wiring, which is preconfigured at the factory for the respective delivery country, is therefore prone to errors.

[0004] In addition, the control electronics must also be configured according to the input voltage used. This is done either through jumpers or switches on the electronics, or, if a microcontroller is used, through appropriate parameter configuration. This step is also preconfigured at the factory. Configuring the control electronics is necessary because different inrush and holding currents must be regulated depending on the coil configuration (parallel, series, nominal voltage).

[0005] To enable customers to subsequently reconfigure the switching device to a different voltage than the factory default, the terminals are accessible behind a screwed cover plate. The contactor configuration is included with the product as a drawing and text in all required languages ​​in a customer-friendly format, e.g., in the form of a device manual or separate installation instructions. The descriptions are therefore very extensive. If the description is not available on-site, correct configuration is difficult or even impossible.

[0006] Another problem is the customer's spare parts inventory. A quick replacement of a defective contactor requires either individual configuration, including rewiring an existing spare contactor, or stocking all necessary variants.

[0007] Furthermore, the documents US 7 483 254 B1, DE 43 04 921 C1 and FR 2 943 840 A1 are known.

[0008] Based on the known contactor, the object of the invention is to provide an arrangement with which the magnetic drive can be converted to a different input voltage simply, quickly and safely.

[0009] The invention solves this problem by means of an arrangement for an automatic configuration of a magnetic drive according to claim 1.

[0010] To minimize downtime in the power distribution system, the simplest possible replacement without complex and error-prone wiring of the coils creates added value for the customer. Short downtimes in the event of faults are now a decisive economic factor when selecting a contactor, since in the area of ​​power distribution, downtime is included in the electricity price. A key advantage of the invention is that it eliminates the need for manual configuration, which is less error-prone and faster than before. Furthermore, despite the somewhat higher manufacturing costs (including routine testing costs and configuration costs), an arrangement according to the invention achieves manufacturing savings because manual configuration effort and verification of correct wiring, possibly even according to the dual control principle, are eliminated.

[0011] The advantage of automatic detection of the input voltage level and the associated automatic coil wiring and configuration of the control electronics is that, on the one hand, errors in manual wiring and configuration are avoided and, on the other hand, fewer variants have to be manufactured.

[0012] Customer documentation can be significantly reduced in volume and is no longer required on-site when replacing a contactor. Customer spare parts inventory is significantly simplified because the number of variants in spare parts inventory is reduced.

[0013] In the context of the invention, the term "automatic" refers to the fact that configuration no longer has to be performed manually by a technician, but is performed automatically by a machine. Preferably, this is done using electronics built into the contactor.

[0014] A magnetic actuator is a type of switchgear commonly used in medium-voltage systems, for example. In this type of switchgear, one or more energized coils generate a magnetic field that attracts another ferromagnetic piece of metal, such as a metal plate called an armature plate. This attraction causes a movement that is transferred to a movable contact in the switchgear, pressing this contact against the fixed contact. Typically, two coils are used that can be connected in parallel or series. This has the advantage that the magnetic force can be kept approximately the same, even if the input voltage is different for the coils in different countries due to different nominal voltages of the power supply, as mentioned at the beginning. When energized, the two coils of the magnetic actuator exert an attractive force on the armature.The transmission mechanism translates the movement of the magnetic armature into a movement of the movable contact toward the fixed contact and features a toggle lever, for example. The magnetic drive features controllable switching devices for the coils.

[0015] A control device is, for example, an electronic circuit or processor that can be configured based on a measured input voltage to control the solenoid drive or its coils. The inrush and holding currents for the coils are regulated.

[0016] A vacuum switching device according to the invention comprises, for example, a fluid-tight housing inside which a vacuum exists (or an extremely low gas pressure below 0.1% atmospheric pressure). If a movable contact is quickly pulled away from a fixed contact, e.g., by a spring force, any resulting arc is quickly extinguished, partly because there is hardly any ionizable medium for current flow. Vacuum switching devices are particularly well suited for switching alternating current because an arc always breaks when the voltage crosses zero.

[0017] The configuration device is a core aspect of the invention. It comprises, for example, a voltage measuring device for measuring the input voltage. Furthermore, the configuration device can configure the control device to the measured input voltage, i.e., communicate the measured input voltage to the control device as a digital or analog value. Furthermore, the configuration device can automatically control the controllable switching devices and thus connect the coils in parallel or series depending on the measured input voltage. The configuration device comprises, for example, an electronic circuit or a processor for data processing.

[0018] In a preferred embodiment of the arrangement according to the invention, the configuration device is designed to connect the coils in parallel for a measured input voltage of 90 V to 150 V and in series for a measured input voltage of 180 V to 250 V. This is advantageous because the magnetic force of the coils is regulated to the intended level.

[0019] In a preferred embodiment of the arrangement according to the invention, the configuration device is designed to connect the coils in parallel for a measured input voltage of 20 V to 29 V and in series for a measured input voltage of 40 V to 72 V. This is an advantage because the magnetic force of the coils is regulated to the intended level.

[0020] In a further preferred embodiment of the arrangement according to the invention, the configuration device is designed to measure an alternating voltage as the input voltage.

[0021] In a further preferred embodiment of the arrangement according to the invention, the configuration device is designed to measure a DC voltage as the input voltage.

[0022] In a further preferred embodiment of the arrangement according to the invention, the configuration device is designed to configure the control device to the measured input voltage by setting the switch-on and holding currents. This is advantageous because the magnetic force of the coils is regulated to the intended level.

[0023] In a further preferred embodiment of the arrangement according to the invention, the controllable switching devices comprise at least one of the following switching devices: MOSFET, IGBT, relay. A MOSFET is a metal-oxide-semiconductor field-effect transistor, and an IGBT is a bipolar transistor with an insulated gate electrode. A relay is a remotely operated switch driven by an electric current, typically with two switching positions. The relay is activated via a control circuit and can switch other circuits.

[0024] In a further preferred embodiment of the arrangement according to the invention, the configuration device is designed to measure the input voltage before each switching operation and to configure the control device and connect the coils. The level of the input voltage is detected before each switching operation. This results, for example, in a delay in switching on. With an alternating voltage as the input voltage, for example, a half-wave, i.e. 10 ms at 50 Hz and 8.3 ms at 60 Hz, can be waited for in order to reliably detect the input voltage. With a direct voltage as the input voltage, there is no delay. If the input voltage is detected via an analog-to-digital converter, there is an additional delay due to the conversion and evaluation in the firmware. However, this delay is a few µs up to a maximum of 1 ms, depending on the type of converter. It is therefore negligible.An additional delay, in the range of several ms, would occur when using relays to switch the coil. This delay does not occur when using electronic switches such as MOSFETs and IGBTs. This design has the advantage that no manual intervention is required to adjust the configuration when the input voltage changes during operation.

[0025] In a further preferred embodiment of the arrangement according to the invention, the configuration device is designed to measure the input voltage during initial commissioning and to save the configuration of the control device and the coil wiring as a data set on a data storage device. The input voltage level is determined automatically, for example, only once during initial commissioning at the end customer's site through one or more test circuits. All necessary configurations for the coil wiring and the setting of the inrush and holding currents are stored persistently on the data storage device and can only be changed or overwritten by manual intervention after commissioning.

[0026] An advantage of this embodiment is that there is no delay during switch-on. Furthermore, this embodiment is less sensitive to (smaller) input voltage fluctuations.

[0027] In a further preferred embodiment of the arrangement according to the invention, the data storage device is designed to securely store the data set even when the power is off. The data storage device can be designed, for example, as a so-called non-volatile memory, meaning that the stored information is retained permanently—even while the computer is not in operation or is not supplied with power. Solid-state disks (SSDs), flash memory, or non-volatile random access memory (NVRAM), for example, can be used. Electrically erasable programmable read-only memory (EEPROM) can also be advantageously employed.

[0028] Based on the known contactor, the object of the invention is to provide a method with which the magnetic drive can be converted to a different input voltage in a simple, quick and safe manner.

[0029] The invention solves this problem by a method for automatic configuration of a magnetic drive according to claim 8. Preferred embodiments of the method according to the invention are explained in the dependent claims 9 to 14. The same advantages arise as explained at the beginning for the arrangement according to the invention.

[0030] To better explain the invention, the figure shows a schematic representation of an embodiment of an arrangement 1 according to the invention.

[0031] The arrangement 1 comprises a vacuum switching device 8-14 with a housing 14 that is fluid-tight and evacuated 13. Inside the housing 14, a movable contact 11 is pressed against a fixed contact 12. This shows the closed state of the switch with the magnetic drive 2-4, 16-19 switched on. A switching rod 8 is connected to the movable contact 11 through the housing 14, with a bellows (not shown), for example, ensuring mobility. For mechanically separating the contacts 11, 12, a spring device 10 is provided, which rests on a support plate 9 and is preloaded in the illustrated closed state.

[0032] The switching rod 8 is connected to a toggle lever 5-7, with the first leg 6 and the second leg 5 connected at a rigid angle but mounted for rotation about the joint 7. The second leg 5 is connected to an armature plate 4 made of metal, e.g., iron. This transmission mechanism 5-7 translates a movement of the magnetic armature 4 into a movement of the movable contact 11 toward the fixed contact 12.

[0033] The magnetic drive 2-4, 16-19 has two coils 2, 3, which can be connected either in parallel or in series using controllable switching devices 16-19. In the illustrated switched-on state, the coils 2, 3 exert an attractive force F on the magnetic armature 4, moving it toward the coils 2, 3.

[0034] A control device 15 for the magnetic drive 2-4, 16-19 can be configured by means of a configuration device 20 to an input voltage measured by a voltage measuring device 21 on a power line 22. The control device 15 regulates the inrush and holding currents for the coils 2, 3.

[0035] The magnetic drive 2-4, 16-19 has controllable switching devices 16-19 for the coils 2, 3. The configuration device 20 connects the coils 2, 3 in parallel or series depending on the measured input voltage using the controllable switching devices 16-19.

[0036] The configuration device 20 internally has data communication connections 30 that connect a processor 24 to a data memory 23, as well as to a voltage measuring device 21 and the control device 15. Furthermore, the switching devices 16-19 are connected to the processor 24 and the control device 15 via data communication connections 30.

Claims

1. Arrangement (1) for automatically configuring a magnetic drive (2-4, 16-19), said arrangement comprising: a vacuum switching device (8-14) having a movable contact (11) and a fixed contact (12), and a magnetic drive (2-4, 16-19) having two coils (2, 3) which can be connected in parallel or in series, wherein the magnetic drive (2-4, 16-19) is designed, in the switched-on state, to exert an attractive force (F) on a magnet armature (4) and to move said magnet armature, and a transfer mechanism (5-7) which is designed to translate a movement of the magnet armature (4) into a movement of the movable contact (11) toward the fixed contact (12), and an actuating device (15) for the magnetic drive (2-4, 16-19), which actuating device can be configured for an input voltage, characterized in that the magnetic drive (2-4, 16-19) has controllable switching devices (16-19) for the coils (2, 3), and in that a configuration device (20) is designed to measure the input voltage and to configure the actuating device (15) for the measured input voltage, and to interconnect the coils (2, 3) in parallel or in series depending on the measured input voltage by means of the controllable switching devices (16-19).

2. Arrangement according to Claim 1, characterized in that the configuration device (20) is designed to connect the coils (2, 3) in parallel for a measured input voltage of 90 V to 150 V and to connect them in series for a measured input voltage of 180 V to 250 V.

3. Arrangement according to Claim 1 or 2, characterized in that the configuration device (20) is designed to configure the actuating device (15) for the measured input voltage by virtue of switch-on and holding currents being set.

4. Arrangement according to any one of the preceding claims, characterized in that the controllable switching devices (16-19) comprise at least one of the following switching devices: MOSFET, IGBT, relay.

5. Arrangement according to any one of the preceding claims, characterized in that the configuration device (20) is designed to measure the input voltage and to configure the actuating device (15) and to interconnect the coils (2, 3) before each switching process.

6. Arrangement according to any one of the preceding claims, characterized in that the configuration device (20) is designed to measure the input voltage upon initial start-up and to save the configuration of the actuating device (15) and the interconnection of the coils (2, 3) as a data set in a data memory (23).

7. Arrangement according to Claim 6, characterized in that the data memory (23) is designed to be able to reliably store the data set in the zero-voltage state as well.

8. Method for automatically configuring a magnetic drive (2-4, 16-19), comprising the following steps: providing a vacuum switching device (8-14) having a movable contact and a fixed contact, and providing a magnetic drive (2-4, 16-19) having two coils (2, 3) which can be connected in parallel or in series, wherein the magnetic drive (2-4, 16-19), in the switched-on state, exerts an attractive force (F) on a magnet armature (4) and moves said magnet armature, and transferring a movement of the magnet armature (4) into a movement of the movable contact (11) toward the fixed contact (12) by means of a transfer mechanism (5-7), and measuring an input voltage by means of a measuring device (21), characterized by the following steps: configuring an actuating device (15) for the magnetic drive (2-4, 16-19) for the input voltage by means of a configuration device (20), and interconnecting the coils (2, 3) in parallel or in series depending on the measured input voltage by means of controllable switching devices (16-19) of the magnetic drive (2-4, 16-19) by means of the configuration device (20).

9. Method according to Claim 8, characterized in that the coils (2, 3) are connected in parallel for a measured input voltage of 90 V to 150 V and are connected in series for a measured input voltage of 180 V to 250 V.

10. Method according to Claim 8 or 9, characterized in that the actuating device (15) is configured for the measured input voltage by virtue of switch-on and holding currents being set.

11. Method according to any one of Claims 8 to 10, characterized in that at least one of the following switching devices is used for the controllable switching devices (16-19): MOSFET, IGBT, relay.

12. Method according to any one of Claims 8 to 11, characterized in that the input voltage is measured and the actuating device (15) is configured and the coils (2, 3) are interconnected before each switching process.

13. Method according to any one of Claims 8 to 12, characterized in that the input voltage is measured upon initial start-up and the configuration of the actuating device (15) and the interconnection of the coils (2, 3) are saved as a data set in a data memory (23).

14. Method according to Claim 13, characterized in that a data memory (23) is used to reliably store the data set in the zero-voltage state as well.