Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
  • H01H47/22—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for supplying energising current for relay coil
  • H01H47/32—Energising current supplied by semiconductor device
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
  • H01F7/1844—Monitoring or fail-safe circuits
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
  • H01H47/22—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for supplying energising current for relay coil
  • H01H47/32—Energising current supplied by semiconductor device
  • H01H47/325—Energising current supplied by semiconductor device by switching regulator
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
  • H01F2007/1888—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings using pulse width modulation
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
  • H01F7/1805—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current
  • H01F7/1811—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current demagnetising upon switching off, removing residual magnetism

Definitions

• the present invention relates to a device for controlling an inductive load, in particular an electromagnet coil, with which a recovery diode is associated, this device comprising an electronic chopper switch arranged in series with the coil and controlled by a modulator. pulse width as a function of a signal delivered by a device for measuring the current of the coil.
• Coil control devices of this type are well known.
• the switch controlled by the pulse width modulator allows the coil to be supplied first with a high so-called inrush current in order to close the magnetic circuit of the electromagnet, then with a reduced current known as holding just necessary to keep the magnetic circuit closed.
• a second so-called fast opening or fast falling transistor, requested by an opening control circuit is therefore interposed in known manner in series with the coil or in parallel with the coil. (See for example document DE-42 27 165 ).
• the object of the invention is to enable the fast opening transistor to be controlled over wide ranges of supply voltage and under a floating voltage with respect to the voltage across the terminals of the coil.
• the supply circuit of the pulse width modulator is a transformer converter with two secondary windings, one of which is connected to the pulse width modulator and the other of which is connected to the grid of the opening transistor via an opening switch activated by the opening signal.
• the opening switch is preferably an optotransistor whose opening causes the discharge of the gate capacitance of the fast opening transistor.
• a circuit comprising a comparator of the DC supply voltage with at least one threshold, the output of the comparator being connected to a call / hold delay element and to a opening delay device via a logic element provided with an input for a low level on-off signal.
• Figure 1 schematically shows a control device according to the invention for a contactor coil.
• FIG. 2 shows an exemplary embodiment of the control of the opening transistor in the device of FIG. 1.
• the device shown is intended to control a coil B of an electromagnetic contactor or, possibly, the coils of two interdependent contactors associated in assembly inverter. It includes a chopping transistor T1 arranged in series with the coil, between the latter and a low potential point, for example 0 volts, and a fast opening transistor T2 also arranged in series with the coil, between the latter. and a line of high potential V +.
• a recovery diode D is arranged in parallel with the series connection of the coil B and of the transistor T2.
• the transistors T1 and T2 are preferably insulated gate transistors; these are MOS transistors, but they can also be bipolar transistors with an insulated gate known as IGBTs.
• the coil B is connected directly to the line V + and the transistor T2 is arranged in series with the coil between the latter and its connection point to the diode D.
• the transistor T2 and the diode D are placed in series and the coil B is arranged in parallel with the assembly T2, D.
• the chopping transistor T1 is connected to the output of a pulse modulator circuit 11 included in a controller circuit 10.
• a sensor 12 of the current flowing in the coil B is connected to the circuit 11 via a peak intensity detector 13.
• the elements making up circuit 11 or associated with circuit 11 are usual and will not be described further.
• Transistors T1, T2 are n-channel IGBT or MOS components.
• the device has on the one hand supply and control terminals 14 making it possible to supply the various electronic circuits and to determine the start and stop of the contactor by means of a switch not indicated and on the other hand a terminal 15 control to determine the on and off of the contactor by a low level signal S for example from an industrial bus or an appropriate control member such as a programmable controller.
• the supply and control terminals 14 are connected via a filter 16 to a rectifier 17 whose output at potential V +, considered below as potential continuous, is connected to transistor T2, to controller circuit 10 and to a transformer converter 20.
• the converter 20 comprises two secondary windings 21, 22 (see FIG. 2).
• the windings 21, 22 are respectively connected by conductors 23, 24 to the controller circuit 10 to supply the latter and to an isolated control opening switch 25; the switch 25, for example an optotransistor, is controlled by the controller 10 via a conductor 26 to turn on or block the transistor T2 in order to power the coil or not.
• the conductor 26 is connected to an opening control circuit 27 which comprises an analog or digital comparator 28 of the voltage applied to the controller circuit 10 by the conductor 23.
• a logic element 29 receives on the one hand the signal leaving the comparator 28 and on the other hand the signal S applicable to circuit 10 via terminal 15; the output of the logic element 29 is connected on the one hand to a call delay / hold member 30a connected to the modulator 1, and on the other hand to an opening delay member 30b to which the conductor 26 is connected
• the opening delay member 30b for example of the RC type, makes it possible to adjust the blocking delay of the transistor T2 and therefore the fallout time of the electromagnet.
• the transistor T3 of the optical component 25 is located so as to allow the discharge of the gate capacitance of the transistor T2 when T3 is blocked.
• a Zener Z diode is arranged in parallel to T2 to protect the latter.
• the controller circuit 10 can be a microcontroller provided with inputs 31 for selecting the size of the coil of the associated contactor.
• the microcontroller can also be provided with doubled inputs and outputs 26, 26 ′ for controlling the coils of two mutually associated contactors as an inverter.
• the device shown operates as follows.
• Coil B is assumed to be initially not supplied, so that the magnetic circuit of the contactor's electromagnet is open.
• the switch not shown which is associated with the terminals 14 is closed, which applies the DC voltage V + to the drain of T2, to the controller circuit 10 and to the converter 20.
• the transistor of the opening switch 25 is passed through the circuit 10 and the gate of the opening transistor T2 is therefore polarized; it follows that T2 is conducting and that, as T1 is also conducting, the coil B is supplied with an inrush current, then a holding current lower than the inrush current when the pulse modulator circuit 11 comes into operation .
• the switch associated with terminals 14 is opened, so that the supply voltage of the circuit decreases from its level V +.
• the delay member 30 applies with the predetermined delay a signal to the optotransistor 25 which is blocked.
• the T2 grid discharges and T2 freezes. A rapid fallout of the electromagnet is thus obtained.
• the same rapid opening operation can be obtained by switching the low-level signal S presented at terminal 15.

Landscapes

• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Electronic Switches (AREA)
• Relay Circuits (AREA)
• Dc-Dc Converters (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=9491702

Family Applications (1)

Country Status (14)

Families Citing this family (27)

Family Cites Families (7)

• 1996
  • 1996-04-25 FR FR9605404A patent/FR2748167B1/fr not_active Expired - Fee Related
• 1997
  • 1997-04-24 EP EP97921876A patent/EP0909451B1/de not_active Expired - Lifetime
  • 1997-04-24 JP JP9537798A patent/JP2000509201A/ja active Pending
  • 1997-04-24 KR KR1019980708407A patent/KR20000010556A/ko not_active Application Discontinuation
  • 1997-04-24 AU AU27783/97A patent/AU722585B2/en not_active Ceased
  • 1997-04-24 CZ CZ983414A patent/CZ341498A3/cs unknown
  • 1997-04-24 ES ES97921876T patent/ES2147447T3/es not_active Expired - Lifetime
  • 1997-04-24 BR BR9709185A patent/BR9709185A/pt unknown
  • 1997-04-24 DE DE69702314T patent/DE69702314T2/de not_active Expired - Fee Related
  • 1997-04-24 PL PL97329524A patent/PL329524A1/xx unknown
  • 1997-04-24 CA CA002252622A patent/CA2252622A1/fr not_active Abandoned
  • 1997-04-24 CN CN97194039A patent/CN1216632A/zh active Pending
  • 1997-04-24 WO PCT/FR1997/000733 patent/WO1997040509A1/fr not_active Application Discontinuation
• 1998
  • 1998-12-22 US US09/147,177 patent/US6031708A/en not_active Expired - Fee Related

Non-Patent Citations (1)

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