EP2663985B1 - Device and method for controlling a switch drive of an electric switch - Google Patents

Description

The invention relates to a device having the features according to the preamble of patent claim 1.

The German patent DE 10 2007 041 972 B3 discloses a device for controlling a switch drive of an electrical switch with a control device which is adapted to evaluate an input side applied to a binary input of the device, generated with an external operating voltage input signal and to make the control of the switch drive in response to the input signal applied to the input side.

The invention has for its object to provide a device of the type described, which is particularly universally applicable.

This object is achieved by a device with the features according to claim 1. Advantageous embodiments of the device according to the invention are specified in subclaims.

Thereafter, the invention provides that the device comprises a reference voltage circuit which is suitable for generating an internal reference voltage with the external operating voltage, the device having a preprocessing device which is suitable for generating a binary signal with the input signal present at the binary input, the logic level thereof depends on the height of the input signal and the height of the reference voltage, and the control device of the device is directly or indirectly in communication with the preprocessing device and evaluates the binary signal of the preprocessing device.

A significant advantage of the device according to the invention is the fact that it can be used for very different external operating voltages. In contrast to previously known devices, the device according to the invention is capable of evaluating input signals present on the input side as a function of the operating voltage with which these input signals have been formed. For this purpose, it is provided according to the invention to generate an internal reference voltage dependent on the external voltage and to evaluate the input signals present at the binary input or the binary inputs by using the internal reference voltage. In contrast to the previously known devices, it is thus possible to use the device for a wide variety of input signals, since it is possible to form and use an internal reference voltage which takes into account the expected level of the input signals present on the input side.

wobei Ui die interne Referenzspannung, Uextern die externe Betriebsspannung und Uoffset den etwaigen Offset bezeichnen. Uoffset kann beispielsweise gleich Null sein.The internal reference voltage is preferably smaller than the external operating voltage. Particularly preferably, the internal reference voltage is generated in such a way that, apart from any offset (voltage offset value), it is proportional to the external operating voltage, it therefore preferably applies: $$\mathrm{Ui}~\mathrm{Uextern}-\mathrm{Uoffset}.$$

where Ui denote the internal reference voltage, Uextern the external operating voltage and Uoffset the possible offset. For example, Uoffset can be zero.

According to a preferred embodiment of the device it is provided that the device has a switching element that allows or prevents a current flow from the binary input through the preprocessing device in dependence on the height of the input signal and the height of the reference voltage, and the logic level of the binary signal from the current flow through the Preprocessing device depends.

For example, the switching element can allow a flow of current from the binary input through the preprocessing device, if the difference between the height of the input signal and the height of the reference voltage exceeds or falls below a predetermined minimum value.

It is also considered advantageous if the preprocessing device is connected to an input terminal to the binary input and an output terminal to the switching element.

The preprocessing device preferably has an optocoupler which generates the binary signal on the output side, wherein the logic level of the binary signal depends on the current flow through the preprocessing device. An optocoupler advantageously enables potential separation.

The reference voltage circuit preferably has a voltage divider, for example a resistive voltage divider.

For example, the voltage divider may have a divider terminal to which the reference voltage is applied, and the divider terminal and the output terminal of the pre-processing means may be connected to the switching element.

The switching element is preferably a transistor or at least also has a transistor. The transistor may be a bipolar transistor. The divider terminal is preferably connected to the base terminal of the transistor and the output terminal of the pre-processing unit is preferably connected to the emitter terminal.

The invention also relates to a method for controlling a switch drive of an electrical switch, wherein an input signal applied to a binary input on the input side and generated with an external operating voltage is evaluated and the control of the switch drive in response to the input signal applied to the input side is made.

According to the invention, provision is made in this regard for the external operating voltage to generate an internal reference voltage, with the input signal present at the binary input generating a binary signal whose logic level depends on the level of the input signal and the magnitude of the reference voltage, and the binary signal is evaluated.

With regard to the advantages of the method according to the invention, reference is made to the above statements in connection with the device according to the invention, since the advantages of the method according to the invention essentially correspond to those of the device according to the invention.

Figur 1

ein Ausführungsbeispiel für eine Vorrichtung zum Steuern eines Schalterantriebs eines elektrischen Schalters,

Figur 2

ein Ausführungsbeispiel für ein Binäreingangsmodul für die Vorrichtung gemäß Figur 1 und

Figur 3

ein weiteres Ausführungsbeispiel für ein Binäreingangsmodul für die Vorrichtung gemäß Figur 1.

The invention will be explained in more detail with reference to embodiments; thereby show by way of example

FIG. 1

An exemplary embodiment of a device for controlling a switch drive of an electrical switch,

FIG. 2

an embodiment of a binary input module for the device according to FIG. 1 and

FIG. 3

a further embodiment of a binary input module for the device according to FIG. 1 ,

For the sake of clarity, the same reference numerals are used in the figures for identical or comparable components.

The FIG. 1 shows an embodiment of a device 4 for controlling a switch drive M of an electrical switch, not shown. The device 4 comprises ports A1 to A5 and one preferably as Semiconductor circuit formed H-bridge circuit 9 and a control device 10 and various preferably designed as semiconductor circuits control modules 11 to 12 for driving and interrogation of analog locks (control module 11) and / or binary feedback (control module 12).

The device 4 also comprises a binary input module 13, which is connected to binary inputs 6a, 6b and 6c of the device 4. The binary inputs 6a, 6b and 6c are acted upon, for example via switches S1, S2 and S3 with an external operating voltage, which is, for example, a control circuit voltage Usk for a control circuit SK of the device 4, a load circuit voltage Ulk for a load circuit LK of the device. 4 or may be another predetermined voltage. In the following example, it is assumed that the external operating voltage is the control circuit voltage Usk for the control circuit SK.

For switching on and off of the control circuit voltage Usk for the control circuit SK and the load circuit voltage Ulk for the load circuit LK switching elements 14 and 15 are provided. The switching elements 14, 15 are preferably relay contacts, which are controlled directly or indirectly by the control device 10.

After switching on the one or more switching elements 14, 15, the associated switching relay is maintained for example via an auxiliary winding (= self-holding). The shutdown then takes place via the control device 10 on the basis of a control signal. For example, the device 4 switches off automatically approx. 1.5 s after the last command has been processed, if no new command is pending.

For monitoring the voltage supply of the H-bridge circuit 9 and the switching elements 14 and 15, a monitoring module 16 may be provided which is connected to the switching elements 14 and 15 is connected. In the event of a malfunction or a malfunction, the supply of the H-bridge circuit 9, in particular the drive elements, and the switching element 14 for the load circuit LK can be switched off by the monitoring module 16.

In addition, 10 further operating and / or safety functions can be realized by means of the control device and used for driving or switching the switch drive M or other elements, such as display elements or control elements. Some examples of freely programmable operating and / or safety functions are described below.

For example, the switch drive M upon reaching an end position of the resources, such. B. the three-position disconnector with the end positions "disconnector on", "OFF", "earthing on" braked. The overrun time of the switch drive M and the braking times are freely programmable. After expiry of the specified braking time and release for manual operation, the motor circuit is automatically opened and released for manual operation. In addition, the device 4 can lock when switching the switch drive to manual mode.

By means of the electronic control can be identified errors, such as wrong direction of rotation of the switch drive M, malfunction of the mechanism of the switch drive, load voltage is missing or no feedback from the auxiliary switch, visualized. For this purpose, 10 display elements can be controlled by means of the control device. Depending on the type of control, the display elements can light permanently or blinking. It can display different levels of interference, the display elements with different clocked flashing light, z. B. with Tf = 0.5 s or Tf = 2 s are controlled.

Furthermore, the feedback and monitoring times of switching operations can be freely programmed. Furthermore, with blocked switch drive M, the motor current can be limited in time. In addition, further suitable control and / or message functions for the operation and safety of the switch drive M can be realized by means of the control device 10.

Depending on the type of power supply, DC or AC voltage, associated voltage transformers 17, 18, in particular AC / DC or DC / DC converters, are provided between the H-bridge circuit 9 and the respective circuit to be supplied - control circuit SK and load circuit LK , For the galvanic isolation of the control circuit SK and the load circuit LK and the internal voltage circuits of the device 4, for example, optocouplers 19 can be used.

In the FIG. 1 It can be seen that the binary input module 13 has a reference voltage circuit 50 which is suitable for generating an internal reference voltage Ui proportional to the external operating voltage. In the embodiment according to FIG. 1 the control circuit voltage Usk is used as the external operating voltage, so that the control circuit voltage Usk is applied to the reference voltage circuit 50 as an external operating voltage.

The binary input module 13 also has a switching element 60 to which the internal reference voltage Ui of the reference voltage circuit 50 is applied.

To the switching element 60 three preprocessing devices are connected, which in the FIG. 1 are denoted by the reference numerals 70, 71 and 72. The three preprocessing devices 70, 71 and 72 are connected to the three binary inputs 6a, 6b and 6c of the device 4 and are thus connected via the switches S1, S2 and S3 to the control circuit voltage Usk.

In addition, in the FIG. 1 recognize that the three preprocessing devices 70, 71 and 72 are connected via binary lines to the control device 10 of the device 4.

In the FIG. 2 is a first embodiment of the binary input module 13 according to FIG. 1 shown in more detail in detail. It can be seen that the control circuit voltage Usk is applied to the reference voltage circuit 50 of the binary input module 13. The reference voltage circuit 50 comprises a diode 51, a capacitor 52 and a voltage divider 53, which forms a divider terminal 54. At the divider terminal 54 drops the internal reference voltage Ui, which is proportional to the control circuit voltage Usk (neglecting the voltage drop across the diode 51). The voltage divider 53 is formed by two ohmic resistors R1 and R2.

Subordinate to the reference voltage circuit 50 is a switching element SE, which is formed by a bipolar pnp transistor. The switching element SE is connected with its base terminal to the divider terminal 54 of the voltage divider 53 of the reference voltage circuit 50.

In the FIG. 2 can be seen that a series resistor Rv is connected to the emitter terminal of the switching element SE, which is acted upon by the control circuit voltage Usk and forms a current limit for the emitter collector path of the switching element SE.

To the emitter terminal of the switching element SE, the three preprocessing devices 70, 71 and 72 are connected, which may for example be of identical design. Subsequently, therefore, only in the FIG. 2 left pre-processing device 70 described in more detail. The two other preprocessing devices 71 and 72 are identical.

One recognizes in the FIG. 2 in that the preprocessing device 70 has an input connection 70e which is connected to the binary input 6a of the device 4 and thus to the switch S1. The input terminal 70e is connected to a diode 100 to which a constant current source 105 is connected. The constant current source 105 is connected via an optocoupler 110 to an output terminal 70 a of the preprocessing device 70. This output terminal 70a is connected to the emitter terminal of the switching element SE in connection.

In the FIG. 2 In addition, it can be seen that the optocoupler 110 forms a signal output 70s of the preprocessing device 70, to which a binary line 701 is connected and which transmits a binary signal B70 to the control device 10 via this binary line 701.

The two other preprocessing devices 71 and 72 are - as already mentioned - designed identically. They also each have a diode 100, a constant current source 105 and an optocoupler 110. Moreover, they are respectively provided with an input terminal 71e and 72e and an output terminal 71a and 72a connected to the emitter terminal of the switching element SE.

The binary signals generated by the two preprocessing devices 71 and 72 are shown in FIG FIG. 2 marked with the reference symbols B71 and B72. These binary signals B71 and B72 reach the control device 10 via binary lines 711 and 721.

• Ist der Schalter S1 - wie in der Figur 2 gezeigt - geöffnet, so liegt an dem Eingangsanschluss 70e der Vorverarbeitungseinrichtung 70 keine Spannung an. In diesem Fall wird kein Strom durch den Optokoppler 110 fließen können, so dass der Optokoppler 110 als Binärsignal B70 eine logische "0" über die Binärleitung 701 zu der Steuereinrichtung 10 schicken wird.

The mode of operation of the binary input module 13 will now be explained in greater detail by way of example with reference to the preprocessing device 70:

• Is the switch S1 - as in the FIG. 2 shown - open, so is applied to the input terminal 70e of the preprocessing device 70 no voltage. In this case, no Current can flow through the optocoupler 110, so that the optocoupler 110 as a binary signal B70 will send a logical "0" via the binary line 701 to the controller 10.

If, however, the switch S1 is closed, the control circuit voltage Usk is applied to the input terminal 70e of the preprocessing device 70 so that the switching element SE will be switched through and the optocoupler will send a logic "1" as a binary signal B70 to the control device 10 via the binary line 701 ,

wobei Umin den Mindestwert, Ui die interne Referenzspannung, Ueb die Emitterbasisspannung des Schaltelements SE und U70 den Spannungsabfall über der Vorverarbeitungseinrichtung 70 bezeichnen.Switching through of the switching element SE is only considered when the emitter base line of the switching element SE is acted upon by a sufficiently high forward voltage. This is always the case when the voltage Ue applied to the emitter of the switching element SE will be approximately 0.7 V greater than the internal reference voltage Ui which is applied to the divider terminal 54 of the voltage divider 53. In other words, there will be a current flow from the binary input 6a of the device 4 by the preprocessing device 70 and a switching of the switching element SE only if the difference between the height of the voltage applied to the input terminal 70e voltage signal and the height of the internal reference voltage Ui a predetermined Exceeds minimum value, which approximates as follows: $$\mathrm{Umin}=\mathrm{Ui}+\mathrm{Ueb}+\mathrm{U}\mathrm{70}.$$

where Umin denotes the minimum value, Ui the internal reference voltage, Ueb the emitter base voltage of the switching element SE and U70 the voltage drop across the preprocessing device 70.

The binary input module 13 processes an input signal applied to the binary inputs 6a, 6b and 6c, that is to say as a function of the internal reference voltage Ui, which leads to an external operating voltage - in this case the control circuit voltage Usk - is approximately proportional, with which in turn the input signal applied to the input side has been formed. This allows the binary input module 13 to correctly process control circuit voltages within a relatively large voltage interval: Thus, in the FIG. 2 Binary input module 13 correctly process input signals that have been formed with an external operating voltage between 20 V and 200 V. For example, if a large external operating voltage is applied, the internal reference voltage Ui relevant for the formation of the binary signal B70 is correspondingly high, whereas if a small external operating voltage or a small control circuit voltage Usk is used, the internal reference voltage Ui will be correspondingly small. The internal reference voltage Ui used to form the binary signal B70 to B72 is always approximately proportional to the external operating voltage, which is used to form the input signals present on the input side.

The device according to FIG. 2 is "high active", which means that when a positive voltage is present at the binary inputs 6a, 6b and 6c, a binary signal B70, B71 or B72 will always be generated with a logical "1".

1. (a) Als externe Betriebsspannung für die drei Schalter S1, S2 und S3 wird nicht der Plusanschluss der Steuerkreisspannung Usk, sondern der Minusanschluss der Steuerkreisspannung Usk verwendet.
2. (b) Die Dioden 100 sowie die Optokoppler 110 in den Vorverarbeitungseinrichtungen 70, 71 und 72 sind mit inverser Verpolung angeschlossen.
3. (c) Anstelle eines pnp-Transistors wird ein npn-Transistor verwendet, dessen Emitteranschluss über einen Vorwiderstand Rv mit dem Minusanschluss der Steuerkreisspannung Usk verbunden ist.

The FIG. 3 shows an exemplary embodiment of a binary input module 13, which is "low active". This means that when the switches S1, S2 and S3 are open, that is to say when there is no current flow through the corresponding preprocessing device 70, 71 and 72, a binary signal B70, B71 or B72 with a logical "1" will be generated. The structure according to FIG. 3 corresponds essentially to the structure according to FIG. 2 , the following changes have been made:

1. (a) As the external operating voltage for the three switches S1, S2 and S3 is not the positive terminal of the control circuit voltage Usk, but the negative terminal of the control circuit voltage Usk used.
2. (b) The diodes 100 and the optocouplers 110 in the preprocessing devices 70, 71 and 72 are connected with inverse reverse polarity.
3. (c) Instead of a pnp transistor, an npn transistor is used whose emitter terminal is connected via a series resistor Rv to the negative terminal of the control circuit voltage Usk.

Incidentally, in particular with regard to the mode of operation, the circuit corresponds to FIG. 3 the circuit according to FIG. 2 ,

LIST OF REFERENCE NUMBERS

4

contraption

6a-6c

binary

9

H-bridge circuit

10

control device

11

control module

12

control module

13

Binary

14

switching element

15

switching element

16

monitoring module

17

DC converter

18

DC converter

19

optocoupler

50

Reference voltage circuit

51

diode

52

capacity

53

voltage divider

54

divider connection

60

switching element

70-72

preprocessing

70a-72a

output port

70e-72e

input port

701-721

Binärleitung

70s

signal output

100

diode

105

Constant current source

110

optocoupler

A1-A5

connection

B70-B72

binary signals

LK

load circuit

M

switch drive

R1, R2

Ohmic resistances

Rv

dropping resistor

SE

switching element

SK

control circuit

S1-S3

switch

Ue

tension

Ui

reference voltage

spoof

Load circuit voltage

Usk

Control circuit voltage

Claims (10)

1. Device (4) for controlling a switch drive (M) of an electric switch with a control apparatus (10) which evaluates an input signal, which is present at a binary input (6a, 6b, 6c) of the device (4) on the input side and which is produced by means of an external operating voltage (Usk), and which effects control over the switch drive (M) as a function of the input signal present on the input side,
   characterised in that

   - the device (4) has a reference voltage circuit (50) which produces an internal reference voltage (Ui) by means of the external operating voltage (Usk),

   - the device has a pre-processing apparatus (70, 71, 72) which produces a binary signal (B70, B71, B72) by means of the input signal present at the binary input (6a, 6b, 6c), the logical level of said binary signal being a function of the level of the input signal and the level of the reference voltage (Ui), and

   - the control apparatus (10) of the device (4) is connected indirectly or directly to the pre-processing apparatus (70, 71, 72) and evaluates the binary signal (B70, B71, B72) of the pre-processing apparatus (70, 71, 72).
2. Device according to claim 1,
   characterised in that

   - the device (4) has a switching element (SE) which allows or prohibits a current flow from the binary input (6a, 6b, 6c) through the pre-processing apparatus (70, 71, 72) as a function of the level of the input signal and the level of the reference voltage (Ui), and

   - the logical level of the binary signal (B70, B71, B72) is a function of the current flow through the pre-processing apparatus (70, 71, 72).
3. Device according to claim 2,
   characterised in that
   the switching element (SE) permits a current flow from the binary input (6a, 6b, 6c) through the pre-processing apparatus (70, 71, 72) if the difference between the level of the input signal and the level of the reference voltage (Ui) exceeds a predetermined minimum value (Umin).
4. Device according to one of the preceding claims 2-3,
   characterised in that
   the pre-processing apparatus (70, 71, 72) is connected by means of an input terminal (70e, 71e, 72e) to the binary input (6a, 6b, 6c) and by means of an output terminal (70a, 71a, 72a) to the switching element (SE).
5. Device according to one of the preceding claims,
   characterised in that
   the pre-processing apparatus (70, 71, 72) has an opto-coupler (110) which on the output side produces the binary signal (B70, B71, B72), wherein the logical level of the binary signal (B70, B71, B72) is a function of the current flow through the pre-processing apparatus (70, 71, 72).
6. Device according to one of the preceding claims,
   characterised in that
   the reference voltage circuit (50) has a voltage divider (53).
7. Device according to claim 6,
   characterised in that
   the voltage divider (53) has a divider terminal (54) to which the reference voltage (Ui) is applied and the divider terminal (54) and the output terminal (70a, 71a, 72a) of the pre-processing apparatus (70, 71, 72) are connected to the switching element (SE).
8. Device according to one of the preceding claims 2-7,
   characterised in that
   the switching element (SE) is a transistor or has a transistor.
9. Device according to claim 8,
   characterised in that
   the transistor is a bipolar transistor and the divider terminal (54) is connected to the basic terminal of the transistor and the output terminal (70a, 71a, 72a) of the pre-processing apparatus (70, 71, 72) is connected to the emitter terminal.
10. Method for controlling a switch drive (M) of an electric switch, wherein an input signal, which is present at a binary input (6a, 6b, 6c) on the input side and which is produced by means of an external operating voltage (Usk), is evaluated, and the control of the switch drive (M) is effected as a function of the input signal present on the input side, characterised in that

    - an internal reference voltage (Ui) is produced by means of the external operating voltage (Usk),

    - a binary signal (B70, B71, B72) is produced by means of the input signal present at the binary input (6a, 6b, 6c), the logical level of said binary signal being a function of the level of the input signal and the level of the reference voltage (Ui), and

    - the binary signal (B70, B71, B72) is evaluated.

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