DE102006053797B4 - AC power controller for electromagnetic switching devices - Google Patents

Abstract

Circuit arrangement for operating an electromagnetic drive (110, 310) of a switching device, wherein the electromagnetic drive (110, 310) is operated with an alternating current controller (120, 220, 320), and the circuit arrangement (240, 340) for actuating the alternating current controller ( 120, 220, 320) having a time function, wherein the time function represents an exponential function, and wherein the means (240, 340) for driving the AC-adjuster (120, 220, 320) comprise an RC element (R5, C2), and the alternating current controller (120, 220, 320) has two anti-series transistors (V4, V5), characterized in that the two anti-serially connected transistors (V4, V5) are adapted to linearly control excess energy, and wherein the circuitry comprises negative feedback resistors (R9 , R10) for balancing the two transistors (V4, V5), wherein the negative feedback resistors (R9, R10) also for adjusting the time function be used.

Description

The The present invention relates to a circuit arrangement for operating an electromagnetic drive of a switching device.

at contactor drives is it for reasons the mechanical and especially the electrical life, the closing speed set the drive to a preferred value in the rated voltage range, so as to increase the mechanical shock load and contact blurring minimize. Another aspect, the closing speed on one setting the ideal value lies in the lead of the auxiliary switches, which should not fall below a minimum value. Especially at Capacitor contactors, the above ON resistances and leading auxiliary contacts precharge the capacitor to be switched, so the inrush currents is sufficient advance of the auxiliary account essential.

at conventional electromagnetic drives, in particular through the increased voltage dependence the drives, only a limited Influencing the closing speed over the mass ratios and the spring forces possible. This applies in particular to drives that are suitable for an extended nominal voltage range are provided.

to Optimization of the turn-on dynamics of contactor drives are therefore included modern drives increase electronically controlled or regulated drives used. So z. B. drives, by a pulse width modulation (PWM) or by a linear reduction of the DC coil voltage the Suiting control or regulate for some years state of the art.

adversely in the known solutions However, these drives are over operate a DC link, so it is DC drives. Especially with large Drives can the holding power for continuous operation to a unacceptable self-heating of the drive. Therefore, with these drives for the lowering of the holding power either a PWM-Moduluation of Coil performance also necessary in holding mode, or the provision a lower holding voltage, z. B. via an integrated switching regulator.

Of the Effort for However, this method of lowering the holding power is very high, especially considering the necessary measures for compliance with electromagnetic compatibility. Especially with drives for higher supply voltages Therefore, the effort for the Lowering the holding power disproportionately high.

From the German patent application DE 21 10 071 A is a Wechselstromerregtes switching device with a in each switching phase adapted to the power requirement tensile force of the solenoid known.

The German Auslegeschrift DE 28 06 628 B1 discloses a circuit arrangement for driving a polarized AC relay whose switching coil is in an AC circuit by means of a pending at the input of the drive circuit level. The polarized relay operates with a mechanical switching contact.

The German patent application DE 31 10 314 A1 discloses a system for operating a relay by means of a computer controlled in dependence on a reference value switching element.

The German patent application DE 41 40 034 A1 discloses a driving circuit for an AC line voltage contactor, through which a load is switchable, with a controlled by an electronic circuit semiconductor switching device, which is in series with the coil of the contactor, wherein the semiconductor switching device is a parallel circuit of two semiconductor switches, whose one for the positive half-waves and the other is provided for the negative half-waves of the AC mains voltage, and wherein this parallel circuit is in series with a capacitor which charges at undisturbed semiconductor switches with the mains frequency across the other semiconductor switch and discharges via the other semiconductor switch.

The German patent application DE 42 19 834 A1 discloses an apparatus and method for in-phase energizing of an electromagnetic switch to close its contacts in response to an ohmic load at the zero crossing of the mains AC voltage.

The German patent application DE 195 20 573 A1 discloses a magnetic contactor with phase switch and a phase angle adjusting device for adjusting the phase angle with which the phase switch, which causes the supply of a voltage to an electromagnet for energizing the electromagnet, wherein the phase switch is driven by a signal generator. When the signal generator is turned on, the solenoid can be energized with a delay determined by a resistance and a capacitance.

From the article "Boost MOSFETs Drive Current to Solid State AC Relay" by Kim Gauen, published in Industrial Control Application, application note EB141, Motorola Inc. 1991, DL 412 D, pages 493 and 494, is a MOSFET amplifier circuit for driving a AC relay, where the amplifier comprises two anti-serially connected MOSFET transistors, known.

The German patent application DE 28 16 558 A1 discloses a circuit arrangement for driving a bistable relay, wherein the exciting current by briefly closing a switching element moves the relay coil.

The German patent application DE 41 17 122 A1 discloses controllable semiconductors for controlling a load-supplying alternating current, wherein the semiconductors are located at the DC voltage output of a rectifier bridge. As controllable semiconductors serve two with their switching paths in series transistors, each switching path is connected in parallel with an inverse diode.

The U.S. Patent No. 4,649,302 discloses a semiconductor switch for controlling a load comprising two FET transistors. The integrated body diodes of the FET transistors are used for rectification.

The U.S. Patent No. 5,004,969 discloses a method and circuit for reverse phase control of an alternating current for a load, wherein voltage controlled semiconductor switches such as MOSFETs and IGBTs are used as electrical switches. The integrated body diodes of the MOSFETs can be used with other diodes to provide full wave rectified direct current to a power supply

Of the The invention is based on the object, a circuit arrangement to create an electromagnetic drive of a switching device, which is an efficient and inexpensive to implement influence the closing speed of the drive allows

These Task is solved by a circuit arrangement for operating an electromagnetic Drive a switching device, wherein the electromagnetic drive with an AC power controller is operated and the circuit arrangement means for driving the AC actuator having a time function, wherein the time function represents an exponential function, and wherein the Have means for controlling the AC-controller an RC element, and the AC controller two antiseries switched transistors , wherein the two anti-serially connected transistors thereto are set up, excess energy linearly cancel, and wherein the circuit arrangement negative feedback resistors for Symmetrization of the two transistors, wherein the negative feedback resistors also be used to adjust the time function.

Of the Electromagnetic drive, for example, an electromagnetic Drive for one or more shooters or for a or more relays or for other switching devices represent. Furthermore, the electromagnetic drive can at least a drive coil, at least one magnetic core and at least one Magnet armature include.

Of the electromagnetic drive is powered by an alternating current or a Operated alternating voltage, wherein the alternating current or the alternating voltage can be influenced by the AC power controller. Thus, for example, via the AC power controller the electromagnetic drive is controlled or regulated, z. B. to turn on the electromagnetic drive, and / or for holding the electromagnetic drive and / or for switching off of the electromagnetic drive. For example, the dynamics of the electromagnetic drive, such as. B. the turn-on and / or the turn-off dynamics, influenced by the AC power controller become. The AC controller can z. B. using a controller or a regulation be controlled or regulated, wherein the AC power controller z. B. at a power-up and / or a Shutdown be controlled with a defined time function can.

Of the For example, AC power can be connected in series with the electrical Drive connected, and this series circuit comprising the AC power and the electric drive can be parallel to an AC voltage source for supplying the electric drive be switched. Thus, the AC power can through the current the at least one drive coil of the electromagnetic drive influence.

For example can the closing speed of the electromagnetic drive in the rated voltage range by the AC regulators can be set to a preferred value, so that the mechanical shock load and contact blurring of the switchgear can be reduced and thus the mechanical and electrical life extended can be. If the switching device one or more shooters represents with at least one auxiliary switch, so for example set the closing speed by means of the AC adjuster be that the lead of the at least one auxiliary switch a minimum value not below.

The circuit arrangement according to the invention has the further advantage that the electromagnetic drive is operated with alternating current and Thus, for example, by the path-dependent change in the inductance of the at least one drive coil, the inductive reactance of the at least one coil and thus the excitation power can be influenced. For example, by suitably selecting the winding parameters, the tightening current and / or the holding current of the at least one drive coil can be tuned to a desired desired value.

Of the AC power controller comprises at least two semiconductor devices such as B. IGBT (Insulated Gate Bipolar Transistor) or transistor. The term AC converter includes all devices with where an alternating current can be controlled or provided, for. B. in dependence a control signal such. B. a control voltage or the like.

The Means for controlling the AC power controller with a time function can for example, by a microcontroller, and / or a DSP and / or implemented another electronic or electrical circuit become. For example, you can the means for controlling the AC actuator a control signal to actuate the Wechellstromstellers according to the time function, such as B. a control voltage.

aid This time function, for example, an excitation current through the at least one drive coil of the switching device can be controlled.

For example can be the time function to control the AC power controller during a power-up of the electric drive for the switching device be used, so that by the time function, the turn-on The electromagnetic drive can be specified. So, for example the means for controlling the AC power controller with the AC voltage be coupled to the supply of the magnetic drive, so that when Apply this AC voltage, such. B. when switching on the magnetic Drive, automatically the time function for the switch-on started is and the AC-drive controlled according to the time function becomes. You can do this the means for controlling the AC actuator, for example also with the AC voltage to supply the magnetic drive electrically be supplied, for. B. can by means of a rectifier from this AC voltage a DC voltage to supply the means for Control of the AC power controller and thus also for the supply of the AC power controller are generated.

The Time function for activation during the Switching can be chosen, for example, so that the AC power controller first only a small current through the at least one coil of the electrical Drive controls and steadily increases this current, bringing the dynamics of the drive can be adapted to the requirements of the switching device. After expiry of the switch-on, the AC power controller can, for example Fully control, so that the current limit of at least one Drive coil, for example, only by the impedance of at least a drive coil takes place. Optionally, however, can be used to limit the current also further impedances or resistances besides the impedance of the at least one drive coil can be used.

Further The time function can also be optionally used to control the AC power controller during one Switching off the electric drive used for the switching device become.

One Another advantage arises from the fact that the overlay the time function of the drive circuit to the own time constant the at least one excitation coil, a formation of a Einschaltwinkelabhängigen DC component almost complete can be avoided. This allows synchronization effects be completely avoided on the phase angle of the control voltage.

A Embodiment of the invention provides that the time function the AC power controller during activates a switch-on.

A Embodiment of the invention provides that the time function a Represents exponential function.

The Exponential function for controlling the AC actuator during the Power up can be a very good compromise from a short Delay time, d. H. a big one Initial steepness, and a natural one Increase excitation.

The Means for driving the AC actuator include an RC element.

By For example, the RC element can be the exponential time function while a switch-on. The realization of the time function by means of the RC element represents a particularly cost-effective Implementation dar.

For example the RC element can be regarded as a two-port, with the input gate a turn-on voltage is applied, e.g. B. by the previously described Rectifier or by another voltage source, so that at Output gate an exponential rising output voltage is applied, with which the AC power controller is controlled.

Of the AC power controller comprises at least two semiconductor devices.

Of the AC power controller comprises at least two semiconductor devices such as B. IGBT (Insulated Gate Bipolar Transistor) or transistor.

The Control of the comprising at least one semiconductor device Wechselstromstellers can, for example, with the previously described Means for controlling the AC actuator with a time function take place, or else by another predetermined control voltage or another predetermined control current.

Of the AC power controller includes two anti-serially connected transistors.

These two anti-serially connected transistors, for example, with the at least one drive coil of the electromagnetic drive form a series connection. For example, these two transistors be two field effect transistors, such as. B. two MOSFETs, the two Transistors can also be two IGBTs or other suitable transistors.

The two anti-serially connected transistors, for example, after expiration be fully controlled by a switch-on, so that the current limit the at least one drive coil, for example, solely by the Impedance of at least one drive coil. Optionally, however for current limiting even more impedances or resistors in addition the impedance of the at least one drive coil can be used.

The For example, two anti-serially connected transistors can use excess energy linear and heat loss dissipate, this applies in particular to a switch-on process and / or a Switching off the electromagnetic drive.

The Circuit arrangement includes negative feedback resistors to Symmetrization of the two transistors.

For example can the two anti-serially connected transistors each in one Emitter circuit (in bipolar transistors) or in a source circuit be operated with negative feedback (in Feldeffektransistoren), being independent of the negative feedback resistances can be achieved by critical transistor parameters. Consequently can the two anti-serially connected transistors, for example each represent a voltage controlled current source, each of the Current sources a negative feedback resistor for current negative feedback having.

A Embodiment of the invention provides that the two antiserial switched transistors are two MOSFET transistors.

A Embodiment of the invention provides that the circuit arrangement comprises two diodes, which together with the integrated body diodes of MOSFET transistors a bridge rectifier for generating a supply voltage for controlling the AC power controller represent.

Become For example, n-channel MOSFETs such. B. n-channel enhancement mode MOSFETS, for the two used anti-serially connected transistors, so can each between the terminal of the p-doped substrate and the drain terminal integrated body diode for the rectification can be used.

Consequently only two more diodes will be available next to the two already existing ones Body diodes of the MOSFET transistors for the construction of the bridge rectifier needed making a cost-effective and space-saving implementation of the circuit achieved can be.

The through the bridge rectifier established supply voltage can, for example, directly to control of the AC actuator, or it may mean for controlling the AC actuator with a time function between the output of the bridge rectifier and be connected to the AC power controller. The above explanations and benefits regarding the means for controlling the AC actuator apply to this Embodiment of the invention equally. So z. B. an RC element between the output of the bridge rectifier and the AC power controller placed so that the AC power controller be controlled with a defined exponential time function can.

Further For example, at the output of the rectifier, a voltage limiting element, such as B. a Z-diode or zener diode operated in the breakdown direction, to limit the voltage of the rectified voltage. Furthermore you can at the output of the rectifier filter means for smoothing the rectified voltage, such as. B. at least one capacitor or other filter media.

A Embodiment of the invention provides that the circuit arrangement a rectifier for generating a supply voltage for Control of the AC actuator includes.

The circuit arrangement can thus also comprise a separate rectifier, this rectifier can be realized for example by a half-wave rectifier, or a bridge rectifier or other rectifier circuit.

As in the previous embodiment of the invention, the rectifier established supply voltage, for example, directly to the control of the AC actuator, or it may mean for controlling the AC actuator with a time function between the output of the bridge rectifier and be connected to the AC power controller. The concerning the previous one Design mentioned explanations and Advantages regarding of the rectifier, the optional means of controlling the AC power controller with a time function, and optional circuits of the output of the rectifier such. B. voltage limiting and / or filter means apply equally for the separate rectifier.

A Embodiment of the invention provides that the rectifier with the AC voltage supplied to operate the electromagnetic drive becomes.

Consequently The AC power controller is then automatically with a control voltage supplied to the electromagnetic drive an AC voltage, z. B. to turn it on, is created.

are Furthermore, for example, the previously described means for driving the AC actuator with a time function between rectifier and AC power switch, so when creating this AC voltage for operating the drive, such. B. when switching of the magnetic drive, automatically the time function for the switch-on process be started and the AC power controller according to the time function be controlled.

A Embodiment of the invention provides that the AC power controller while a power-on, an excess power rectified linearly.

includes the AC power controller, for example, two electronic switching elements, such as B. transistors, so can this excess power or linearly adjust energy and dissipate it as heat loss.

A Embodiment of the invention provides that the circuit arrangement Means for overvoltage protection includes.

So can For example, overvoltage protection be connected in parallel with the AC power controller, z. B. for protection the electronic switching elements of the AC power controller such as Transistors. For example, you can Thus, these electronic switching elements before Abschaltspitzen the at least one drive coil to be protected when switching off. These surge protectors parallel to the AC controller, for example, by a Varistor can be realized.

Further can for example, overvoltage protection at the circuit input, at the z. B. the input AC voltage is applied, be placed, where z. B. a varistor can be used can. Also these surge protection means placed at the circuit input can protect the electronic switching elements of the AC actuator, such as z. B. when switching off Abschaltspitzen the at least one drive coil at Switch off.

The The invention will be described below with reference to exemplary embodiments showing drawings explained in more detail.

there demonstrate:

1 : A schematic representation of a first embodiment of the circuit arrangement according to the invention for operating an electromagnetic drive;

2 : A schematic representation of a second embodiment of the circuit arrangement according to the invention for operating an electromagnetic drive;

3 : A detailed representation of a third embodiment of the circuit arrangement according to the invention for operating an electromagnetic drive;

1 shows a schematic representation of a first embodiment of the circuit arrangement according to the invention for operating an electromagnetic drive of a switching device, wherein the electromagnetic drive with an AC power controller 120 is operated, and the circuit arrangement means for controlling the AC power controller 120 having a time function, wherein the time function represents an exponential function, and wherein the means for controlling the AC power controller 120 having an RC element, and the AC power controller 120 has two anti-series transistors, wherein the two antipersonal transistors are arranged to linearly control excess energy, and wherein the circuit arrangement negative feedback resistors for balancing the two transistors wherein the negative feedback resistors are also used to adjust the time function.

The electromagnetic drive can represent, for example, an electromagnetic drive for one or more contactors, or for one or more relays or for other switching devices. The electromagnetic drive comprises at least one drive coil 110 , and may comprise at least one magnetic core and at least one armature (not in 1 shown).

The at least one drive coil 110 is connected in series with the AC power controller 120 , wherein an AC voltage U _e can be applied to this series connection. This AC voltage U _e thus serves as a supply voltage for the at least one drive coil 110 wherein the alternating current flowing through the at least one drive coil through the AC power controller 120 can be influenced.

So can the AC power controller 120 for example, in a first state by the at least one drive coil 110 influence flowing current so that it is below a first threshold, so that the magnetic drive opens, and the AC power controller 120 For example, in a second state by the at least one drive coil 110 influence flowing current such that it is above a second threshold, so that the magnetic drive closes.

Furthermore, the AC power controller 120 the current through the at least one drive coil 110 during a closing operation of the electromagnetic drive, ie the transition from the first to the second state, specifically control, so that the turn-on dynamics of the electromagnetic drive can be influenced. Thus, for example, the closing speed of the electromagnetic drive in the nominal voltage range can be set to a preferred value, so that z. B. the mechanical shock load and the contact blurring of the switching device can be reduced and thus the mechanical and the electrical life can be extended. If the switching device represents one or more contactors with at least one auxiliary switch, the closing speed can also be adjusted by controlling the current during the switch-on process, for example by means of the alternating current controller, so that the overshoot of the at least one auxiliary switch does not fall below a minimum value.

For example can be alike by controlling the flow during a turn-off operation of the electromagnetic drive, d. H. from the transition from the second to the first state, the turn-off dynamics of the electromagnetic Drive can be influenced.

Consequently can with the circuit arrangement according to the invention in a simple way the turn-on dynamics and / or turn-off dynamics of the an electric drive for a switching device influenced become.

The inventive circuit arrangement shows the further advantage that the electromagnetic drive operated with alternating current is and thus, for example, by the path-dependent change in the inductance of at least a drive coil of the inductive reactance of at least one Coil and thus the excitation power can be influenced. For example can by appropriate choice of the winding parameters of the suit and / or the holding current of the at least one drive coil to a desired Setpoint to be tuned.

The AC power controller 120 comprises at least two semiconductor switching elements such. B. IGBT (Integrated Gate Bipolar Transistor) transistor. The term AC converter includes all devices with which an AC can be controlled or provided, for. B. in response to a control signal such. B. a control voltage or the like.

Furthermore, the AC power controller 120 be controlled for example via the AC voltage U _e , so that z. B. when switching the AC voltage U _{e of} the AC power controller 120 the current through the at least one drive coil 110 controls in accordance with a predefined switch-on characteristic.

The AC power controller 120 However, can also be controlled or regulated otherwise, for. B. by a microcontroller or the like.

The to the first embodiment mentioned explanations and benefits apply equally for the following embodiments.

2 shows a schematic representation of a second embodiment of the circuit arrangement according to the invention for operating an electromagnetic drive of a switching device, wherein the electromagnetic drive with an AC power controller 220 is operated, and the circuit arrangement means for controlling the AC power controller 220 having a time function, wherein the time function represents an exponential function, and wherein the means for controlling the AC power controller 220 have an RC element, and the AC power controller 220 two anti-serially connected transistors, wherein the two anti-serially connected transistors are adapted to linearly control excess energy, and wherein the circuit arrangement comprises negative feedback resistors for balancing the two transistors, wherein the negative feedback resistors are also used to adjust the time function.

As in the first embodiment, the at least one drive coil is located 110 in series with the AC power controller 220 , wherein an AC voltage U _e can be applied to this series connection. This AC voltage U _e thus serves as a supply voltage for the at least one drive coil 110 wherein the alternating current flowing through the at least one drive coil through the AC power controller 120 can be influenced.

The above explanations and advantages with respect to the AC power controller 120 The first embodiment applies equally to the in 2 shown AC-control 220 ,

Furthermore, the circuit arrangement for operating an electromagnetic drive in the second embodiment shown comprises means for controlling the AC power controller 220 with a time function 240 , and optionally a rectifier 230 and optional means for overvoltage protection 250 . 260 ,

The means for controlling the AC actuator 220 with a time function 240 can be realized for example by a microcontroller, and / or a DSP and / or other electronic or electrical circuit. This time function allows the AC power controller 220 For example, the excitation current through the at least one drive coil 110 depending on the time according to the predetermined time function control. For example, the means for controlling the AC actuator 220 with a time function 240 output a control voltage for controlling the AC power controller depending on the time function.

For example This time function can be used to control the AC power controller while a turn-on of the electric drive can be used so that by the time function, the turn-on dynamics of the electromagnetic Drive can be specified.

Furthermore, the means for controlling the AC power controller 220 with a time function 240 be coupled with AC voltage U _e to supply the magnetic drive, such. In 2 over the rectifier 230 in that the AC voltage U _{e is} also used as the control voltage for the means for controlling the AC voltage regulator 220 with a time function 240 can work. For example, when applying the AC voltage U _e , such. B. when the magnetic drive, by this AC voltage U _e automatically a time function for the control of the AC power controller 220 be started during the switch-on and the AC power controller are controlled according to the time function. The means for controlling the AC actuator 220 with a time function 240 Thus, for example, a defined increasing control voltage as a function of the time function during the switch-on to the AC power controller 220 output. This time function during the switch-on process can be realized for example by an exponential function.

For example, a rectifier 230 generate from the AC voltage U _e a DC supply voltage, with which the means for controlling the AC power controller 220 with a time function 240 be supplied. Thus, the means for driving the AC actuator 220 with a time function 240 be automatically turned on when the AC voltage U _e , z. B. to turn on the electric drive, is applied, so that, for example, as previously described thereby automatically the AC power controller 220 can be controlled according to a predetermined time function during the switch-on.

The rectifier 230 can be realized for example by a half-wave rectifier, or a bridge rectifier or other rectifier circuit. At the output of the rectifier 230 may be a voltage limiting element, such. As a driven in the breakdown direction zener diode or Zener diode, to limit the voltage of the rectified voltage. Furthermore, can be at the output of the rectifier 230 Filter means for smoothing the rectified voltage are such. B. at least one capacitor or other filter means.

The means for controlling the AC actuator 220 with a time function 240 comprise an RC element. Thus, if, for example, an alternating voltage U _{e is applied} for switching on the magnetic drive, then the output of the rectifier is present 230 Accordingly, a rectified turn-on, which in turn can be applied to the input of the RC element, so that at the output of the RC element, an exponentially increasing output voltage is output, with the AC controller 220 can be controlled during the switch-on. From a certain output voltage gel of the RC element controls the AC power controller 220 fully through and thus switches to the second state described above.

Another advantage arises from the fact that the superimposition of the time function of the drive circuit on the own time constant of the at least one exciter coil 110 a training of Einschaltwinkelabhängigen DC component is almost completely avoided. As a result, synchronization effects on the phase position of the control voltage are completely avoided.

Furthermore, the in 2 shown circuitry overvoltage protection 250 . 260 include. For example, overvoltage protection 260 directly parallel to the AC power controller 220 be switched, z. B. to protect the electronic switching elements of the AC power controller such as transistors. For example, thus, these electronic switching elements before Abschaltspitzen the at least one drive coil 110 protected during shutdown. These surge protectors 260 directly parallel to the AC power controller 220 can be realized for example by a varistor. Furthermore, overvoltage protection can also be used 250 be placed at the circuit input, in which case z. B. a varistor can be used. Also these surge protection means placed at the circuit input 250 can the electronic switching elements of the AC power controller 220 protect, z. B. when switching off Abschaltspitzen the at least one drive coil 110 when switching off.

Although the inverter 230 , the means for controlling the AC power controller 220 with a time function 240 and the AC power controller 220 in the 2 are shown as separate units, these units can fuse together in terms of circuitry, so that, for example, transistors of the AC power controller 220 at the same time as diodes for the rectifier 230 to be used with. Are z. B. antiseries switched MOSFET transistors for the AC power controller 220 used, for example, the integrated body diodes of these MOSFET transistors, together with two other diodes, a bridge rectifier for generating a supply voltage for the means for controlling the AC power controller 220 with a time function 240 and thus to control the AC-controller 220 form.

3 shows a detailed representation of a third embodiment of the circuit arrangement according to the invention for operating an electromagnetic drive of a switching device.

The AC power controller 320 which is in series with the at least one drive coil 310 the magnetic drive is connected, comprises the two anti-serially connected MOSFET transistors V4 and V5.

The control of the transistors V4 and V5 takes place from a supply voltage consisting of the diodes V1, V2 and V3, the resistors R2 and R3 and not in 3 drawn body diodes of the transistors V4 and V5 is constructed. Here, the diodes V1 and V2 together with the body diodes of the transistors V4 and V5 form a bridge rectifier whose negative pole is applied to the junction of the resistors R9 and R10. The series resistors R2 and R3 may be formed high impedance and thus serve to limit the supply current. The diode V3, which may be a zener diode, operates in the breakdown direction and limits the output voltage of the bridge rectifier. Furthermore, the output voltage of the bridge rectifier can be low-pass filtered by filter means, ie, for example, the capacitor C1, and thus be smoothed, in particular during the zero crossings of the alternating voltage U _e .

Furthermore, the in 3 shown circuit arrangement means for driving the AC power controller 320 with a time function 340 comprising an RC element comprising a resistor R5 and a capacitor C2. This RC element is fed with the smoothed by the capacitor C1 output voltage of the bridge rectifier. Upon application of an AC voltage U _e , the rectified and smoothed output voltage is thus applied to the RC element R5 / C2, and to the transistors V4 and V5 of the AC current regulator 320 a defined increasing control voltage is supplied. As a result, the transistors V4 and V5 are driven and the excitation current of the at least one drive coil 310 is increased according to the time function of the RC element defined. About the negative feedback resistors R9 and R10, the Zener diode V3, the RC element R5 / C2 and the divider resistor R6, the increase of the excitation current, and thus largely the dynamics of the electromagnetic drive can be adapted to the requirements of the switching device. As already explained in the second exemplary embodiment, in terms of circuit technology, the components can be AC converters 320 , Means for controlling the AC actuator with a time function 340 and rectifiers fuse together; Thus, in the third exemplary embodiment, the body diodes of the MOSFET transistors V4 and V5 together with the diodes V1 and V2 form a bridge rectifier, and the time function can also be influenced, for example, via the negative feedback resistors R9 and 10 and / or the Zener diode V3 or the divider resistor R6.

During the Turning on becomes excess energy linear over the transistors V4 and V5 regulated and dissipated as heat loss. Even though while the power-up process in the short term to make a big performance can, is over the relatively short switching times the total power dissipation of the transistors V4 and V5 low.

After the switch-on process, the transistors V4 and V5 are completely turned on, so that the current limit of the at least one drive coil 310 now by the impedance of the at least one drive coil 310 he follows.

The Time function for controlling the AC actuator in the form of a Exponential function, which is realized cost-effectively by the RC element R5 / C2 can be a good compromise from a possible cheap solution, a short delay time and thus large initial slope and a natural Pathogen increase with.

Furthermore, the in 3 shown circuit arrangement means for overvoltage protection, such as. B. the parallel to the AC power controller 320 switched varistor R11, which the AC power controller 320 protects against overvoltages. Together with the varistor R1, the varistor R11 limits simultaneously occurring cut-off peaks of the at least one drive coil 310 ,

The resistors R9 and R10, which as described above for adjusting the time function for driving the AC power controller 320 be used, also have the task as negative feedback resistors to balance the transistors V4 and V5 to minimize dependence on critical transistor parameters, such. B. compensate for different threshold voltage of the transistors V4 and V5.

by virtue of the simplicity of the circuit, the very low control power requirement and the very good protection of the control transistors against overvoltages This circuit concept is very well suited for high mains voltages up to 690 VAC.

Another advantage arises from the fact that the superimposition of the time function of the drive circuit on the own time constant of the at least one exciter coil 310 a training of Einschaltwinkelabhängigen DC component is almost completely avoided. As a result, synchronization effects on the phase position of the control voltage are completely avoided.

These third embodiment represents a possible Realization of the shown schematic first and / or second embodiment in this respect, the respects apply the first and second embodiments mentioned explanations and benefits alike for this third embodiment.

Claims (7)

Circuit arrangement for operating an electromagnetic drive ( 110 . 310 ) of a switching device, wherein the electromagnetic drive ( 110 . 310 ) with an alternating current controller ( 120 . 220 . 320 ), and the circuit means ( 240 . 340 ) for controlling the AC actuator ( 120 . 220 . 320 ) having a time function, the time function being an exponential function, and wherein the means ( 240 . 340 ) for controlling the AC actuator ( 120 . 220 . 320 ) comprise an RC element (R5, C2), and the alternating current controller ( 120 . 220 . 320 ) has two anti-serially connected transistors (V4, V5), characterized in that the two anti-series transistors (V4, V5) are adapted to linearly control excess energy, and wherein the circuit arrangement negative feedback resistors (R9, R10) for balancing the two transistors (V4, V5), the negative feedback resistors (R9, R10) also being used to adjust the time function. Circuit arrangement according to claim 1, characterized in that the time function of the AC power controller ( 120 . 220 ) during a switch-on operation. Circuit arrangement according to claim 1 or 2, characterized characterized in that the two anti-serially connected transistors two MOSFET transistors (V4, V5) are. Circuit arrangement according to Claim 3, characterized in that the MOSFET transistors each have integrated body diodes, and the circuit arrangement has two diodes (V1, V2) which, together with the integrated body diodes of the MOSFET transistors (V4, V5), form a bridge rectifier for generating a diode Supply voltage for controlling the AC actuator ( 120 . 220 . 320 ). Circuit arrangement according to one of claims 1-3, characterized in that the circuit arrangement comprises a rectifier ( 230 ) for generating a supply voltage for driving the AC power controller ( 120 . 220 . 320 ) having. Circuit arrangement according to Claim 4 or 5, characterized in that the rectifier ( 230 ) with the AC voltage for operating the electromagnetic drive ( 110 . 310 ) is supplied. Circuit arrangement according to one of claims 1-7, characterized in that the circuit arrangement is connected in parallel with the inverter means for overvoltage protection ( 250 . 260 ) having.