WO1988010059A1 - Method for feeding an electric fence and a pulse generator for carrying out the method - Google Patents

Method for feeding an electric fence and a pulse generator for carrying out the method Download PDF

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Publication number
WO1988010059A1
WO1988010059A1 PCT/SE1988/000305 SE8800305W WO8810059A1 WO 1988010059 A1 WO1988010059 A1 WO 1988010059A1 SE 8800305 W SE8800305 W SE 8800305W WO 8810059 A1 WO8810059 A1 WO 8810059A1
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WO
WIPO (PCT)
Prior art keywords
load
pulse
storage unit
charge storage
secondary winding
Prior art date
Application number
PCT/SE1988/000305
Other languages
French (fr)
Inventor
Göran ALMHAGEN
Anders Lindmark
Original Assignee
Internationell Affärsutveckling I Bjärred Ab
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Internationell Affärsutveckling I Bjärred Ab filed Critical Internationell Affärsutveckling I Bjärred Ab
Publication of WO1988010059A1 publication Critical patent/WO1988010059A1/en

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Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05C—ELECTRIC CIRCUITS OR APPARATUS SPECIALLY DESIGNED FOR USE IN EQUIPMENT FOR KILLING, STUNNING, OR GUIDING LIVING BEINGS
    • H05C1/00—Circuits or apparatus for generating electric shock effects
    • H05C1/04—Circuits or apparatus for generating electric shock effects providing pulse voltages

Definitions

  • the present invention relates to a method for feed ⁇ ing an electric fence by means of a rechargeable charge storage unit and a transformer having a primary winding through which the charge storage device is discharge- able, and a secondary winding to which the electric fence is connected.
  • the invention also relates to a pulse gene ⁇ rator for carrying out the method.
  • Pulse generators for electric fences may be connected to the mains or be battery- powered.
  • the demands that the user, the farmer, places on a pulse generator is that it should be reliable, maintenance-free and consume little energy in the case of a battery-powered pulse generator.
  • pulse generators According to regu- lations set by the authorities, pulse generators must not emit such current or voltage as may cause damage to people or be a fire hazard.
  • the pulse generator should have a high power output, also causing drying of growing grass which would otherwise bring about undesired ground contact.
  • the power output is however maximized, generally to 5 J at a load of 500 ohm, while a power limit below this load value is seldom set.
  • the object of the present invention is to provide a method for feeding an electric fence of the type stated in the introduction to this specification, and to a pulse generator for carrying out the method, the method and the pulse generator making it possible to produce a sufficient shock effect independently of the load of the pulse generator.
  • this object is achieved by determining the load on the secondary winding of the transformer for each pulse generated by the discharge of the charge storage unit, and by controlling the charge storage unit so as to supply additional energy to the same pulse if the load exceeds a predetermined load value.
  • the pulse generator being characterized by having a load detector arranged to determine the load on the secon ⁇ dary winding of the transformer for each pulse gene ⁇ rated therein by the discharge of the charge storage unit, and a trigger circuit controlled by the load detector and arranged to control the charge storage unit so as to supply additional energy to the same pulse if the load exceeds a predetermined load value.
  • the predetermined load value generally is 500 ohm.
  • the invention ensures automatic adjustment of the power output according to the load on the fence, more particularly in such a manner that the maximum power output stipulated by the authorities for the predetermined load value is emitted precisely at this predetermined load value, whereby the shock effect at the predetermined load value and at lower load values becomes sufficient while, at loads above the predetermined load value, the required shock effect is obtained by increasing the power output for each separate pulse.
  • the inventive concept yields a number of advan ⁇ tages, such as reduced power consumption and, thus, increased battery life in the case of a battery-powered pulse generator.
  • the change of the power output is readily adaptable to current regulations in different countries and also involves the advantage of extend ⁇ ing the life of the pulse generator.
  • the load on the secon ⁇ dary winding of the transformer is determined prefer ⁇ ably on the basis of the maximum value of the voltage of the pulse generated in the secondary winding, and the pulse is supplied with additional energy if the maximum value falls below a predetermined value.
  • the invention suitably to determine the load on the secondary winding of the transformer on the basis of the difference between the maximum value of the voltage of the pulse generated in the secondary winding and a value representing the current of the pulse at a corresponding point of time, the additional energy being supplied if said difference is negative.
  • the pulse generator more particularly has a load detector arranged to determine the load on the secondary winding of the transformer for each pulse generated therein by the discharge of the charge storage unit, and a trigger circuit controlled by the load detector and arranged to control the charge storage unit so as to supply additional energy to the same pulse if the load ex ⁇ ceeds a predetermined load value.
  • the load detector suitably comprises a voltage level detector for determining the load on the basis of the maximum value of the voltage of the pulse gene ⁇ rated in the secondary winding, the trigger circuit being arranged to control the charge storage unit so as to supply the additional energy to the same pulse if the maximum value falls below a predeter ⁇ mined value.
  • the transformer suitably has a sensing winding connected to the voltage level detector and producing a pulse proportional to the voltage of the pulse in the secondary winding.
  • the load detector further suitably has a current level detector producing an output signal proportional to the current of the pulse in the secondary winding, said load detector being arranged to determine the load on the basis of the difference between the out- put signal of the voltage level detector and the out ⁇ put signal of the current level detector, and the additional energy being supplied if said difference is negative.
  • the charge storage device may suitably comprise two or more capacitors which are dischargeable each by a thyristor switch, one of said capacitors giving rise to the pulse in the secondary winding when clos ⁇ ing the associated thyristor switch, and another of said capacitors giving rise to the supply of additional energy by the trigger circuit closing the associtated thyristor switch.
  • Fig. 1 is a circuit diagram for a conventional pulse generator for use in an electric fence.
  • Fig. 2 is a schematic diagram for a pulse generator according to the invention for use in an electric fence.
  • Fig. 3 illustrates an embodiment of the charge storage device in a pulse generator according to the invention for use in an electric fence.
  • Fig. 4 is a circuit dia ⁇ gram for a preferred embodiment of the load detector and the trigger circuit in a pulse generator accord ⁇ ing to the invention for use in an electric fence.
  • Fig. 5 shows an example of pulses from the pulse gene- rator according to the invention.
  • the conventional pulse generator shown in Fig. 1 for use in an electric fence consists of a charging unit 1 by means of which a capacitor 2 in a charge storage unit 3 can be charged. Via a thyristor 5 con ⁇ trolled by a trigger circuit 4, the capacitor 2 is repetitively dischargeable through the primary winding 7 of a transformer 6.
  • the secondary winding 8 of the transformer 6 is connected both to the wire 9 of the electric fence and to ground.
  • a voltage limiter (not shown) may be connected between the secon ⁇ dary winding 8 of the transformer 6 and the electric fence.
  • the charging unit 1 may be battery-powdered or connected to the mains and generally charges the capa ⁇ citor 2 to a voltage of about 600 V.
  • the trigger cir ⁇ cuit 4 supplies ignition pulses to the thyristor 5 at a predetermined repetition frequency, e.g. at time intervals of about 1 s.
  • the amount of energy supplied by the conventional pulse generator is constant and independent of the load of . the electric fence on the transformer 6. If the load is high, i.e. the resistance between the electric fence wire and the ground is low, there is thus obtained a pulse of relatively low voltage on the fence wire while, when the load is low, the pulse will have comparatively higher voltage.
  • the pulse generator according to the invention shown in Fig. 2 has a dynamic load detector 10 arranged for each emitted pulse to determine the load on the secondary winding 8 of the transformer 6 and, when the load exceeds a predetermined value, to supply additional energy to the same pulse and, thus, increase the voltage on the fence wire.
  • the predetermined load value may correspond, for instance, to a resistance of 500 ohm.
  • the load can be determined by determining the voltage of the pulse at a certain point of time, e.g. its maximum, presupposing however constant charging of the charge storage unit.
  • a certain point of time e.g. its maximum
  • presupposing however constant charging of the charge storage unit it is advantageously made on the basis of the relationship between the voltage and the current of the pulse at a certain point of time, e.g. at the time of the maximum value of the voltage.
  • the charge storage unit 3 r according to the inven ⁇ tion shown in Fig. 3 has two capacitors 11, 12 which, each via a diode 13 and 14, respectively, can be charged from the charging unit 1 (not shown).
  • the capacitor 11 is connected in series with a thyristor 15 through a first primary winding 16 of the transformer 6' while the capacitor 12 is connected in series with a second thyristor 17 through a second primary winding 18 of the transformer 6'.
  • the transformer 6' has a further winding 19 serv ⁇ ing as a sensing winding and connected to a first in ⁇ put of the load detector 10.
  • a second input of the load detector 10 is connected through a conductor part 20 in the discharge path for the capacitor 11 in the charge storage unit 3 ' .
  • a pulse induced in the sensing winding 19 at the same time as the pulse in the secondary winding 8 is a reflexion of the pulse in the secondary winding in respect of its voltage.
  • the current through the conductor part 20 upon discharge of the capacitor 11 is a measure of the charge of the capacitor 11 and also of the current accompanying the pulse induced in the secondary winding 8. From the signals on its two inputs, the load detector 10 can thus, by suitably weighting the input signals, determine the load on the secondary winding 8 of the transformer 6 r for each pulse generated;
  • the mode of operation of the circuit in Fig. 3 is as follows. With the capacitors 11 and 12 charged, the trigger circuit 4 emits an ignition pulse to the thyristor 15 , whereby the charge of the capacitor 11 is discharged through the primary winding 16 of the transformer 6' , the thyristor 15 and the conductor part 20. The pulse induced in the secondary winding 8 is applied to the electric fence wire 9. During a first part of the pulse in the secondary winding 8, the load detector 10 determines the load of the secondary winding 9, more specifically whether this load exceeds or falls below a predetermined load value.
  • the load detector 10 controls the trigger circuit 4 so as to emit an ignition pulse to the thyristor 17, whereby the capacitor 12 is discharged through the second primary winding 18 of the transformer 6 ' .
  • the trigger circuit 4 emits no ignition pulse to the thyristor 17, and the capacitor 12 is not dis ⁇ charged.
  • the diodes 13 and 14 isolate the capacitors 11 and 12 from each other, such that no renewed charg- ing of the capacitor 12 is required in this case be ⁇ fore the emission of the next pulse to the electric fence wire 9.
  • FIG. 4 A preferred embodiment of the trigger circuit 4 and the load detector 10 in Fig. 3 is shown in Fig. 4.
  • the input of the load detector 10 connected to the sensing winding 19 constitutes the input of a first amplifier 21, and the input of the load detector 10 connected to the conductor part 20 constitutes the input of a second amplifier 22.
  • These two amplifiers are suitably operational amplifiers of high input impedance.
  • the output of the amplifier 21 is connected both to a derivation circuit 23 and to the negative input of a comparator 24.
  • the output of the amplifier 22 is connected both to a derivation circuit 25 and to the positive input of the comparator 24.
  • the output of the comparator 24 is connected to the data input 5 of a D-type flip-flop 26.
  • the derivation circuit 23 is connected via a zero crossing detector 27 both to the clock input of the D-type flip-flop 26 and to the reset input of a counter 28.
  • the derivation circuit 25 is connected via a zero crossing detec- Q tor 29 to the clock input of a second D-type flip-flop 30.
  • the set input of the D-type flip-flop 26 is con ⁇ nected to ground, its Q output is connected to the gate of the thyristor 17, and its reset input is con ⁇ nected to the Q output of the flip-flop 30.
  • the data 5 input of the flip-flop 30 is connected to ground, its reset input is connected to the Q output of the flip-flop 26, and its set input is connected to an output from the counter 28, on which output a pulse appears for every 64 pulses on the input of the counter 0 28 which is supplied with a pulse train having a pulse frequency of 50 Hz.
  • Said counter output is connected to the gate of the thyristor 15 and is connected via a diode 31 to the counter input.
  • the mode of operation of the circuit in Fig. 5 is as follows.
  • an ignition pulse is emitted to the thyristor 15
  • the operation of the counter 28 is interrupted, and the flip-flop 30 is set, i.e. its Q output is "0".
  • the input signals appearing by the ignition of the thyristor 15 on the amplifiers 21 and 22 are ampli ⁇ fied thereby and compared in the comparator 24 whose output signal is "1" if the load on the secondary winding 8 of the transformer 6 ' exceeds the predeter ⁇ mined load value, and "0" if the load on the secondary 5 winding 8 of the transformer 6' falls below the predeter ⁇ mined load value.
  • the output signal of the amplifier 21 is derived by the derivation circuit 23, and the zero crossing detector 27 emits a pulse to the clock input of the flip-flop 26 when the output signal from the derivation circuit 23 is zero, i.e. when the pulse in the sensing winding 19 and thus the pulse in the secondary winding 8 have a maximum voltage value. If the output signal from the comparator 24 then is "1", an ignition pulse will be emitted to the thyristor 17, and the flip-flop 30 is at the same time reset and, in turn, resets the flip-flop 26. The clock pulse to the flip-flop 26 also resets the counter 28 which again starts counting the pulses in the pulse train on its input. However, if the output signal from the comparator 24 is "0", no ignition pulse is emitted to the thyristor 17, but the counter 28 is reset for a new pulse count.
  • the pulse on the output of the zero crossing detector 27 will appear before the pulse on the output of the zero crossing detector 29.
  • This detector will reset the flip-flop 30 when the flip-flop 26 is not emitting any pulse on its Q output, and the flip-flop 30 in turn resets the flip flop 26.
  • the pulse on the output of the zero crossing detector 29 will however appear before the pulse on the output of the zero crossing detector 27.
  • the flip-flop 30 will thus be reset and itself reset the flip-flop 26 before this receives its clock pulse.
  • no ignition pulse is emitted to the thyristor 17, which is however not desirable in this case.
  • Fig. 5 there are shown two pulses 32 and 33, the pulse 32 corresponding to the case where the load on the secondary winding 8 of the transformer 6 is below the predetermined load value, i.e. no additional energy is supplied, while the pulse 33 corresponds to the case where the load is above the predetermined load value and, thus, additional energy is supplied to the same pulse on the basis of which the load de ⁇ termination has been made, more particularly in the descending part of the pulse.
  • the total pulse time is not extended by this procedure and, hence, a consider ⁇ able increase of the shock effect can be achieved by increasing the maximum value of the voltage of the pulse.
  • the components 25, 29 and 30 can be dispensed with. Further, if the charging of the capacitors 11 and 12 can be made invariable, the amplifier 22 can also be cancelled, and the positive input of the comparator 24 can be connected to a constant reference potential.
  • the charge storage unit 3 ' in Fig. 3 it is possible to use the unit according to Fig. 1 if the thyristor 5 is a quenchable thyristor.
  • the input signals of the comparator 24 may, for example, be changed, such that the flip-flop 26 on its Q output emits a quenching pulse to the thy ⁇ ristor 5 if the load on the secondary winding 8 of the transformer 6 1 falls below the predetermined load value.

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  • Life Sciences & Earth Sciences (AREA)
  • Insects & Arthropods (AREA)
  • Generation Of Surge Voltage And Current (AREA)
  • Catching Or Destruction (AREA)
  • Power-Operated Mechanisms For Wings (AREA)

Abstract

In a method for feeding an electric fence, use is made of a rechargeable charge storage unit (3') and a transformer (6') having a primary winding (16, 18) through which the charge storage unit (3') is dischargeable, and having a secondary winding (8) to which the electric fence (9) is connected. A pulse generator for carrying out the method has a load detector (10) which is arranged to determine the load on the secondary winding (8) of the transformer (6') for each pulse generated therein by the discharge of the charge storage unit (3'), and a trigger circuit (4) controlled by the load detector (10). The trigger circuit is arranged to control the charge storage unit (3') so as to supply additional energy to the same pulse if the load exceeds a predetermined load value.

Description

METHOD FOR FEEDING AN ELECTRIC FENCE AND A PULSE GENERATOR FOR CARRYING OUT THE METHOD
The present invention relates to a method for feed¬ ing an electric fence by means of a rechargeable charge storage unit and a transformer having a primary winding through which the charge storage device is discharge- able, and a secondary winding to which the electric fence is connected. The invention also relates to a pulse gene¬ rator for carrying out the method.
Electric fences are used to prevent animals from leaving a fenced area. Pulse generators for electric fences may be connected to the mains or be battery- powered. The demands that the user, the farmer, places on a pulse generator is that it should be reliable, maintenance-free and consume little energy in the case of a battery-powered pulse generator. According to regu- lations set by the authorities, pulse generators must not emit such current or voltage as may cause damage to people or be a fire hazard.
To produce a sufficient shock effect, when touch¬ ing the electric fence, to have the animals avoid the fence, the pulse generator should have a high power output, also causing drying of growing grass which would otherwise bring about undesired ground contact. According to the safety regulations in most countries, the power output is however maximized, generally to 5 J at a load of 500 ohm, while a power limit below this load value is seldom set.
The object of the present invention is to provide a method for feeding an electric fence of the type stated in the introduction to this specification, and to a pulse generator for carrying out the method, the method and the pulse generator making it possible to produce a sufficient shock effect independently of the load of the pulse generator. In the method stated by way of introduction, this object is achieved by determining the load on the secondary winding of the transformer for each pulse generated by the discharge of the charge storage unit, and by controlling the charge storage unit so as to supply additional energy to the same pulse if the load exceeds a predetermined load value.
The inventive object is further achieved by the pulse generator being characterized by having a load detector arranged to determine the load on the secon¬ dary winding of the transformer for each pulse gene¬ rated therein by the discharge of the charge storage unit, and a trigger circuit controlled by the load detector and arranged to control the charge storage unit so as to supply additional energy to the same pulse if the load exceeds a predetermined load value. As appears from the foregoing, the predetermined load value generally is 500 ohm.
The invention ensures automatic adjustment of the power output according to the load on the fence, more particularly in such a manner that the maximum power output stipulated by the authorities for the predetermined load value is emitted precisely at this predetermined load value, whereby the shock effect at the predetermined load value and at lower load values becomes sufficient while, at loads above the predetermined load value, the required shock effect is obtained by increasing the power output for each separate pulse. The inventive concept yields a number of advan¬ tages, such as reduced power consumption and, thus, increased battery life in the case of a battery-powered pulse generator. The change of the power output is readily adaptable to current regulations in different countries and also involves the advantage of extend¬ ing the life of the pulse generator. According to the invention, the load on the secon¬ dary winding of the transformer is determined prefer¬ ably on the basis of the maximum value of the voltage of the pulse generated in the secondary winding, and the pulse is supplied with additional energy if the maximum value falls below a predetermined value.
However, to avoid'dependence on the recharging of the charge storage unit, it is provided according to the invention suitably to determine the load on the secondary winding of the transformer on the basis of the difference between the maximum value of the voltage of the pulse generated in the secondary winding and a value representing the current of the pulse at a corresponding point of time, the additional energy being supplied if said difference is negative.
To avoid the supply of additional energy if the load is capacitive, the phase difference between the voltage and the current of the pulse is suitably de¬ termined. The pulse generator according to the invention more particularly has a load detector arranged to determine the load on the secondary winding of the transformer for each pulse generated therein by the discharge of the charge storage unit, and a trigger circuit controlled by the load detector and arranged to control the charge storage unit so as to supply additional energy to the same pulse if the load ex¬ ceeds a predetermined load value.
The load detector suitably comprises a voltage level detector for determining the load on the basis of the maximum value of the voltage of the pulse gene¬ rated in the secondary winding, the trigger circuit being arranged to control the charge storage unit so as to supply the additional energy to the same pulse if the maximum value falls below a predeter¬ mined value. The transformer suitably has a sensing winding connected to the voltage level detector and producing a pulse proportional to the voltage of the pulse in the secondary winding. The load detector further suitably has a current level detector producing an output signal proportional to the current of the pulse in the secondary winding, said load detector being arranged to determine the load on the basis of the difference between the out- put signal of the voltage level detector and the out¬ put signal of the current level detector, and the additional energy being supplied if said difference is negative.
The charge storage device may suitably comprise two or more capacitors which are dischargeable each by a thyristor switch, one of said capacitors giving rise to the pulse in the secondary winding when clos¬ ing the associated thyristor switch, and another of said capacitors giving rise to the supply of additional energy by the trigger circuit closing the associtated thyristor switch.
The invention will now be described in more detail hereinbelow with reference to the accompanying draw¬ ings. Fig. 1 is a circuit diagram for a conventional pulse generator for use in an electric fence. Fig. 2 is a schematic diagram for a pulse generator according to the invention for use in an electric fence. Fig. 3 illustrates an embodiment of the charge storage device in a pulse generator according to the invention for use in an electric fence. Fig. 4 is a circuit dia¬ gram for a preferred embodiment of the load detector and the trigger circuit in a pulse generator accord¬ ing to the invention for use in an electric fence. Fig. 5 shows an example of pulses from the pulse gene- rator according to the invention.
The conventional pulse generator shown in Fig. 1 for use in an electric fence consists of a charging unit 1 by means of which a capacitor 2 in a charge storage unit 3 can be charged. Via a thyristor 5 con¬ trolled by a trigger circuit 4, the capacitor 2 is repetitively dischargeable through the primary winding 7 of a transformer 6. The secondary winding 8 of the transformer 6 is connected both to the wire 9 of the electric fence and to ground. In some cases, a voltage limiter (not shown) may be connected between the secon¬ dary winding 8 of the transformer 6 and the electric fence.
The charging unit 1 may be battery-powdered or connected to the mains and generally charges the capa¬ citor 2 to a voltage of about 600 V. The trigger cir¬ cuit 4 supplies ignition pulses to the thyristor 5 at a predetermined repetition frequency, e.g. at time intervals of about 1 s.
The amount of energy supplied by the conventional pulse generator is constant and independent of the load of . the electric fence on the transformer 6. If the load is high, i.e. the resistance between the electric fence wire and the ground is low, there is thus obtained a pulse of relatively low voltage on the fence wire while, when the load is low, the pulse will have comparatively higher voltage. The pulse generator according to the invention shown in Fig. 2 has a dynamic load detector 10 arranged for each emitted pulse to determine the load on the secondary winding 8 of the transformer 6 and, when the load exceeds a predetermined value, to supply additional energy to the same pulse and, thus, increase the voltage on the fence wire. The predetermined load value may correspond, for instance, to a resistance of 500 ohm.
The load can be determined by determining the voltage of the pulse at a certain point of time, e.g. its maximum, presupposing however constant charging of the charge storage unit. In order to make the load determination independent of the charging of the capa¬ citor, it is advantageously made on the basis of the relationship between the voltage and the current of the pulse at a certain point of time, e.g. at the time of the maximum value of the voltage.
The charge storage unit 3 r according to the inven¬ tion shown in Fig. 3 has two capacitors 11, 12 which, each via a diode 13 and 14, respectively, can be charged from the charging unit 1 (not shown). The capacitor 11 is connected in series with a thyristor 15 through a first primary winding 16 of the transformer 6' while the capacitor 12 is connected in series with a second thyristor 17 through a second primary winding 18 of the transformer 6'. The transformer 6' has a further winding 19 serv¬ ing as a sensing winding and connected to a first in¬ put of the load detector 10. A second input of the load detector 10 is connected through a conductor part 20 in the discharge path for the capacitor 11 in the charge storage unit 3 ' .
A pulse induced in the sensing winding 19 at the same time as the pulse in the secondary winding 8 is a reflexion of the pulse in the secondary winding in respect of its voltage. The current through the conductor part 20 upon discharge of the capacitor 11 is a measure of the charge of the capacitor 11 and also of the current accompanying the pulse induced in the secondary winding 8. From the signals on its two inputs, the load detector 10 can thus, by suitably weighting the input signals, determine the load on the secondary winding 8 of the transformer 6r for each pulse generated;
The mode of operation of the circuit in Fig. 3 is as follows. With the capacitors 11 and 12 charged, the trigger circuit 4 emits an ignition pulse to the thyristor 15 , whereby the charge of the capacitor 11 is discharged through the primary winding 16 of the transformer 6' , the thyristor 15 and the conductor part 20. The pulse induced in the secondary winding 8 is applied to the electric fence wire 9. During a first part of the pulse in the secondary winding 8, the load detector 10 determines the load of the secondary winding 9, more specifically whether this load exceeds or falls below a predetermined load value. If the load exceeds the predetermined load value, the load detector 10 controls the trigger circuit 4 so as to emit an ignition pulse to the thyristor 17, whereby the capacitor 12 is discharged through the second primary winding 18 of the transformer 6 ' . This results in the supply of additional energy to the pulse in the secondary winding 8 produced by the discharge of the capacitor 11, which takes place during the descending part of this pulse, the voltage of which can thus be considerably increased.
If the load of the load detector 10 is however established as being below the predetermined load value, the trigger circuit 4 emits no ignition pulse to the thyristor 17, and the capacitor 12 is not dis¬ charged. The diodes 13 and 14 isolate the capacitors 11 and 12 from each other, such that no renewed charg- ing of the capacitor 12 is required in this case be¬ fore the emission of the next pulse to the electric fence wire 9.
A preferred embodiment of the trigger circuit 4 and the load detector 10 in Fig. 3 is shown in Fig. 4. The input of the load detector 10 connected to the sensing winding 19 constitutes the input of a first amplifier 21, and the input of the load detector 10 connected to the conductor part 20 constitutes the input of a second amplifier 22. These two amplifiers are suitably operational amplifiers of high input impedance. The output of the amplifier 21 is connected both to a derivation circuit 23 and to the negative input of a comparator 24. The output of the amplifier 22 is connected both to a derivation circuit 25 and to the positive input of the comparator 24. The output of the comparator 24 is connected to the data input 5 of a D-type flip-flop 26. The derivation circuit 23 is connected via a zero crossing detector 27 both to the clock input of the D-type flip-flop 26 and to the reset input of a counter 28. The derivation circuit 25 is connected via a zero crossing detec- Q tor 29 to the clock input of a second D-type flip-flop 30. The set input of the D-type flip-flop 26 is con¬ nected to ground, its Q output is connected to the gate of the thyristor 17, and its reset input is con¬ nected to the Q output of the flip-flop 30. The data 5 input of the flip-flop 30 is connected to ground, its reset input is connected to the Q output of the flip-flop 26, and its set input is connected to an output from the counter 28, on which output a pulse appears for every 64 pulses on the input of the counter 0 28 which is supplied with a pulse train having a pulse frequency of 50 Hz. Said counter output is connected to the gate of the thyristor 15 and is connected via a diode 31 to the counter input.
The mode of operation of the circuit in Fig. 5 is as follows. When the counter 28 has counted 64 pulses, an ignition pulse is emitted to the thyristor 15, the operation of the counter 28 is interrupted, and the flip-flop 30 is set, i.e. its Q output is "0". The input signals appearing by the ignition of the thyristor 15 on the amplifiers 21 and 22 are ampli¬ fied thereby and compared in the comparator 24 whose output signal is "1" if the load on the secondary winding 8 of the transformer 6 ' exceeds the predeter¬ mined load value, and "0" if the load on the secondary 5 winding 8 of the transformer 6' falls below the predeter¬ mined load value. The output signal of the amplifier 21 is derived by the derivation circuit 23, and the zero crossing detector 27 emits a pulse to the clock input of the flip-flop 26 when the output signal from the derivation circuit 23 is zero, i.e. when the pulse in the sensing winding 19 and thus the pulse in the secondary winding 8 have a maximum voltage value. If the output signal from the comparator 24 then is "1", an ignition pulse will be emitted to the thyristor 17, and the flip-flop 30 is at the same time reset and, in turn, resets the flip-flop 26. The clock pulse to the flip-flop 26 also resets the counter 28 which again starts counting the pulses in the pulse train on its input. However, if the output signal from the comparator 24 is "0", no ignition pulse is emitted to the thyristor 17, but the counter 28 is reset for a new pulse count.
When the load on the secondary winding of the transformer 6' is substantially resistive, the pulse on the output of the zero crossing detector 27 will appear before the pulse on the output of the zero crossing detector 29. This detector will reset the flip-flop 30 when the flip-flop 26 is not emitting any pulse on its Q output, and the flip-flop 30 in turn resets the flip flop 26.
When the load on the secondary winding 8 of the transformer 6' is capacitive, the pulse on the output of the zero crossing detector 29 will however appear before the pulse on the output of the zero crossing detector 27. The flip-flop 30 will thus be reset and itself reset the flip-flop 26 before this receives its clock pulse. Thus, no ignition pulse is emitted to the thyristor 17, which is however not desirable in this case.
In Fig. 5, there are shown two pulses 32 and 33, the pulse 32 corresponding to the case where the load on the secondary winding 8 of the transformer 6 is below the predetermined load value, i.e. no additional energy is supplied, while the pulse 33 corresponds to the case where the load is above the predetermined load value and, thus, additional energy is supplied to the same pulse on the basis of which the load de¬ termination has been made, more particularly in the descending part of the pulse. The total pulse time is not extended by this procedure and, hence, a consider¬ able increase of the shock effect can be achieved by increasing the maximum value of the voltage of the pulse. Several modifications of the embodiments described above are conceivable within the scope of the invention. If, for instance, the load can always be assumed to be resistive, the components 25, 29 and 30 can be dispensed with. Further, if the charging of the capacitors 11 and 12 can be made invariable, the amplifier 22 can also be cancelled, and the positive input of the comparator 24 can be connected to a constant reference potential. As an alternative to the charge storage unit 3 ' in Fig. 3, it is possible to use the unit according to Fig. 1 if the thyristor 5 is a quenchable thyristor.
In this latter case, the input signals of the comparator 24 may, for example, be changed, such that the flip-flop 26 on its Q output emits a quenching pulse to the thy¬ ristor 5 if the load on the secondary winding 8 of the transformer 61 falls below the predetermined load value. Further embodiments are evident to those skilled in the art.

Claims

1. Method for feeding an electric fence by means of a rechargeable charge storage unit (3, 3' ) and a transformer (6, 6' ) having a primary winding (7, 16, 18) through which said charge storage unit (3, 3' ) is dischargeable, and a secondary winding (8) to which the electric fence (9) is connected, c h a ¬ r a c t e r i z e d in that the load on the secondary winding (8) of the transformer (6, 6' ) is determined for each pulse generated by the discharge of the charge storage unit (3, 3' ), and that the charge storage unit is controlled so as to supply additional energy to the same pulse if the load exceeds a predetermined load value.
2. Method as claimed in claim 1, c h a r a c - t e r i z e d in that said load is determined on the basis of the maximum value of the voltage of the pulse generated in the secondary winding (8), and that said additional energy is supplied if the maximum value falls below a predetermined value.
3. Method as claimed in claim 1, c h a r a c ¬ t e r i z e d in that said load is determined on the basis of the difference between the maximum value of the voltage of the pulse generated in the secondary winding (8) and a value representing the current of the pulse at a corresponding point of time, and that said additional energy is supplied if said difference is negative.
4. Method as claimed in any one of claims 1-3, c h a r a c t e r i z e d in that the phase difference between the voltage and the current of the pulse is determined, and that the supply of additional energy is inhibited if the load is capacitive.
5. Pulse generator for use in electric fences, comprising a rechargeable charge storage unit (3, 3' ) and a transformer (6, 6' ) having a primary winding (7, 16, 18) through which said charge storage unit (3, 31 ) is dischargeable, and a secondary winding (8) to which the electric fence (9) is connected, c h a r a c t e r i z e d by a load detector (10) arranged to determine the load on the secondary winding (8) of the transformer (6, 6' ) for each pulse generat¬ ed therein by the discharge of said charge storage unit (3, 3r), and a trigger circuit (4) controlled by said load detector (10) and arranged to control the load storage unit (3, 3' ) so as to supply additional energy to the same pulse if the load exceeds a pre¬ determined load value.
6. Pulse generator as claimed in claim 5, c h a - r a c t e r i z e d in that the load detector (10) comprises a voltage level detector (21, 23, 26, 27) for determining the load on the basis of the maximum value of the voltage of the pulse generated in the secondary winding (8), said trigger circuit (4) being arranged to control the charge storage unit (3, 3' ) so as to supply said additional energy if the maximum value falls below a predetermined value.
7. Pulse generator as claimed in claim 6, c h a ¬ r a c t e r i z e d in that the transformer (6r) has a sensing winding (19) which is connected to the voltage level detector (21, 23, 26, 27) and generates a pulse proportional to the voltage of the pulse in the secondary winding (8) .
8. Pulse generator as claimed in claim 6 or 7 , c h a r a c t e r i z e d in that the load detector
(10) further has a current level detector (20, 22) generating an output signal proportional to the cur¬ rent of the pulse in the secondary winding (8), and that the load detector (10) is arranged to determine the load on the basis of the difference between the output signal of the voltage level detector (21, 23, 26, 27) and the output signal of the current level detector (20, 22), said trigger circuit (4) being arranged to control the charge storage unit (3, 3' ) so as to supply said additional energy if said dif¬ ference is negative.
9. Pulse generator as claimed in any one of claims 5-7, c h a r a c t e r i z e d in that the charge storage unit (3' ) comprises two capacitors (11, 12) which are dischargeable each by means of a thyristor switch (15, 17) and of which the capacitor (11) gives rise to the pulse in the secondary winding (8) upon closure of the associated thyristor switch (15), and of which the second capacitor (12) gives rise to said supply of additional energy upon closure of the asso¬ ciated thyristor switch (17).
10. Pulse generator as claimed in any one of claims 5-9, c h a r a c t e r i z e d in that the load detector (10) also comprises a phase detector (30) for determining whether the load is capacitive and, in that case, prevents the supply of said addi- tional energy.
PCT/SE1988/000305 1987-06-05 1988-06-03 Method for feeding an electric fence and a pulse generator for carrying out the method WO1988010059A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8702350A SE457497B (en) 1987-06-05 1987-06-05 SET TO FEED AN ELECTRIC STEEL AND IMPACTOR BEFORE THE IMPLEMENTATION OF THE SET
SE8702350-3 1987-06-05

Publications (1)

Publication Number Publication Date
WO1988010059A1 true WO1988010059A1 (en) 1988-12-15

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Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (3)

Country Link
AU (1) AU1802488A (en)
SE (1) SE457497B (en)
WO (1) WO1988010059A1 (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0454543A1 (en) * 1990-04-25 1991-10-30 RHOMER, Brigitte Electric fence with variable energy
EP0514222A2 (en) * 1991-05-17 1992-11-19 Gallagher Electronics Limited A method and apparatus pertaining to communications
EP0543621A1 (en) * 1991-11-18 1993-05-26 Gallagher Electronics Limited Improvements and modifications to electric fence energisers
DE4140628A1 (en) * 1991-12-10 1993-06-17 Ako Werke Gmbh & Co Electric fence equipment giving load-dependent charging voltage - includes operational amplifier responsive to combination of storage capacitor voltage and average amplitude of output pulse
FR2709225A1 (en) * 1993-08-17 1995-02-24 Horizont Geraetewerk Electric fence apparatus.
WO2000035253A1 (en) * 1998-12-08 2000-06-15 Gallagher Group Limited Improvement to electric fence energisers
DE19836050A1 (en) * 1998-08-11 2001-04-26 Ako Agrartech Gmbh & Co Kg Electrified fence has control device to vary spacing between pulses and increases pulse energy and fence voltage simultaneously, if pulse voltage falls between successive pulses for same pulse energy
DE19953460A1 (en) * 1999-11-05 2001-05-10 Ako Agrartech Gmbh & Co Kg Electric field fencing device measures fence load at HV output of current pulse generating device via measurement of delivered current pulse energy
WO2001084892A2 (en) * 2000-05-01 2001-11-08 Tru-Test Limited An electric fence energiser
EP1595431A2 (en) * 2003-02-05 2005-11-16 Gallagher Group Limited An assembly for the control of fenceline electrical parameters
JP2010197045A (en) * 2003-02-11 2010-09-09 Taser Internatl Inc Electronic type disabling device
US8120212B2 (en) 2007-03-23 2012-02-21 Lacme Holding Method for the control of an electric fence energizer
EP2775803A1 (en) * 2013-03-07 2014-09-10 Lemenager, Chapron Electric fence electrifier
DE102007024026B4 (en) * 2007-04-02 2017-11-16 Ako-Agrartechnik Gmbh & Co. Kg Energizer and method of operating a pasture fence

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NZ272112A (en) * 1995-05-12 1997-10-24 Stafix Electric Fencing Ltd Electric fence pulse generator: pulse height maintained while duration varied according to fence load

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1514726B1 (en) * 1965-06-24 1973-02-01 Schecker Geb Block Circuit for generating shock voltage pulses for training animals
DE2149834A1 (en) * 1971-10-06 1973-04-12 Hans Grossheim ELECTRIC FISHING DEVICE
DE2438582A1 (en) * 1974-08-10 1976-02-26 Utina Elektrowerk Gmbh Electronic circuit for driving an electric fence - produces pulses of a defined shape and limited amplitude and duration under all normal conditions

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1514726B1 (en) * 1965-06-24 1973-02-01 Schecker Geb Block Circuit for generating shock voltage pulses for training animals
DE2149834A1 (en) * 1971-10-06 1973-04-12 Hans Grossheim ELECTRIC FISHING DEVICE
DE2438582A1 (en) * 1974-08-10 1976-02-26 Utina Elektrowerk Gmbh Electronic circuit for driving an electric fence - produces pulses of a defined shape and limited amplitude and duration under all normal conditions

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2661589A1 (en) * 1990-04-25 1991-10-31 Hamm Jean Jacques VARIABLE ENERGY ELECTRIC FENCE.
EP0454543A1 (en) * 1990-04-25 1991-10-30 RHOMER, Brigitte Electric fence with variable energy
EP0514222A2 (en) * 1991-05-17 1992-11-19 Gallagher Electronics Limited A method and apparatus pertaining to communications
EP0514222A3 (en) * 1991-05-17 1993-01-20 Gallagher Electronics Limited A method and apparatus pertaining to communications
EP0543621A1 (en) * 1991-11-18 1993-05-26 Gallagher Electronics Limited Improvements and modifications to electric fence energisers
US5514919A (en) * 1991-11-18 1996-05-07 Gallagher Electronics Limited Electric fence energizer having a continuously varying range of output pulse voltages
DE4140628A1 (en) * 1991-12-10 1993-06-17 Ako Werke Gmbh & Co Electric fence equipment giving load-dependent charging voltage - includes operational amplifier responsive to combination of storage capacitor voltage and average amplitude of output pulse
FR2709225A1 (en) * 1993-08-17 1995-02-24 Horizont Geraetewerk Electric fence apparatus.
DE19836050B4 (en) * 1998-08-11 2005-04-21 Ako-Agrartechnik Gmbh & Co. Kg Electric fence
DE19836050A1 (en) * 1998-08-11 2001-04-26 Ako Agrartech Gmbh & Co Kg Electrified fence has control device to vary spacing between pulses and increases pulse energy and fence voltage simultaneously, if pulse voltage falls between successive pulses for same pulse energy
WO2000035253A1 (en) * 1998-12-08 2000-06-15 Gallagher Group Limited Improvement to electric fence energisers
DE19953460A1 (en) * 1999-11-05 2001-05-10 Ako Agrartech Gmbh & Co Kg Electric field fencing device measures fence load at HV output of current pulse generating device via measurement of delivered current pulse energy
DE19953460B4 (en) * 1999-11-05 2008-04-10 Ako-Agrartechnik Gmbh & Co. Kg Electric fence
WO2001084892A3 (en) * 2000-05-01 2002-01-24 Pel Ind Ltd An electric fence energiser
WO2001084892A2 (en) * 2000-05-01 2001-11-08 Tru-Test Limited An electric fence energiser
EP1595431A2 (en) * 2003-02-05 2005-11-16 Gallagher Group Limited An assembly for the control of fenceline electrical parameters
EP1595431A4 (en) * 2003-02-05 2008-03-19 Gallagher Group Ltd An assembly for the control of fenceline electrical parameters
JP2010197045A (en) * 2003-02-11 2010-09-09 Taser Internatl Inc Electronic type disabling device
US8120212B2 (en) 2007-03-23 2012-02-21 Lacme Holding Method for the control of an electric fence energizer
DE102007024026B4 (en) * 2007-04-02 2017-11-16 Ako-Agrartechnik Gmbh & Co. Kg Energizer and method of operating a pasture fence
EP2775803A1 (en) * 2013-03-07 2014-09-10 Lemenager, Chapron Electric fence electrifier
FR3003119A1 (en) * 2013-03-07 2014-09-12 Chapron Lemenager ELECTRICAL CLOSURE ELECTRICAL

Also Published As

Publication number Publication date
AU1802488A (en) 1989-01-04
SE457497B (en) 1988-12-27
SE8702350D0 (en) 1987-06-05

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