AU2004235593B2

AU2004235593B2 - Installation designed for the operation of a building door and method for controlling the power supply of such an installation

Info

Publication number: AU2004235593B2
Application number: AU2004235593A
Authority: AU
Inventors: Serge Bruno
Original assignee: Somfy SA
Current assignee: Somfy SA
Priority date: 2003-12-19
Filing date: 2004-12-02
Publication date: 2009-02-19
Anticipated expiration: 2024-12-02
Also published as: FR2864371B1; EP1553688B1; AU2004235593A1; ATE341852T1; DE602004002665D1; EP1553688A1; FR2864371A1; CN1641508A; DE602004002665T2; ES2245274T3; ES2245274T1; CN100449448C

Abstract

The installation has an alternating/direct voltage converter comprising a rectifier (REC) and a capacitor (CM) between input terminals of a direct current motor (MOT) mechanically connected to a door (GD) of a building or a gate. The capacitor is charged by a rectified alternating voltage (V1) through a switch (TR) controlled by a control circuit (3) at a frequency of the rectified voltage. An independent claim is also included for an installation supply control method.

Description

i- b

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant (s) SOMFY SAS Invention Title INSTALLATION DESIGNED FOR THE OPERATION OF A BUILDING DOOR AND METHOD FOR CONTROLLING THE POWER SUPPLY OF SUCH AN

INSTALATION

The following statement is a full description of this invention, including the best method of performing it known to me/us Installation designed for the operation of a build'n door and method for controlling the power supply of such an installation FIELD OF THE INVENTION The invention relates to a power supply method defined by the introduction to claim 1. It also relates to an installation for the implementation of this method.

PRIOR ART An activation mechanism designed to operate a mobile closure element generally comprises a DC motor, a reducer gear and a kinematic link between the exit of the reducer gear and the mobile Closure element. The electrical power of the motor is of the order of about a hundred watts.

A significant part of the power of the motor is dissipated in mechanical losses in the reducer gear.

Since this reducer gear is usually irreversible, it allows the mobile element to be blocked as soon as the motor is no longer powered.

A geared motor mechanism normally designed for driving automobile windshield wipers is frequently used in garage door and entrance gate operating systems in order to take advantage of the low manufacturing costs 0I A nsalliation mcimdesignedt operat e a builig rdoor r and ho foinmtrollin thetpwern supplyi of ohersuch gar an instaoblelatoueeeet h TheA sinvnicnt rearte o ah power supl mthoo deie bysithed inodcionitocaim lo .e it also relates toean.

ialltion forbte impmettione bofkethis metod.th An actardmto mechanism designed toeopered ao moilen atemreduer gearshand ther moie clreuelemuent The elerical poorn ofnthane moti ofpe order ofsem abou sigifctak aratag of the pow oanfathctor ios resulting from.the high production volumes. This geared o motor is fitted with a worm gear. It is also possible 0to use a higher-efficiency reversible geared motor ci o associated with a complementary device that ensures the blocking of the mobile closure element when the motor is not powered.

0 One problem posed by the supply of power to DC motors eused in these applications relates to the secure locking of the door.

en Indeed, an important advantage linked to the use of a Smotorized door operation is generally its 0 ci irreversibility, originating from the reducer gear or else from the presence of a complementary element for blocking the motor rotor. As soon as the motor is no longer powered, it is impossible for a criminal to open the door unless by forcible and violent means equivalent to the destruction of a lock.

In order to ensure secure locking of the door, the motor must be able to apply a high torque in the locking phase where its speed is falling as the elastic parts are subject to mechanical tension.

Another potential problem relates to sticking points in the door trajectory. A sticking point can, for example, be caused by a defect in the mechanical structure of the door, such as a local deformation in a slider or a guide rail. Once "learnt" (in order to be differentiated from an obstacle), the sticking point should not cause the motor to slow down which would give the door movement a jerky aspect casting doubt on the quality of the drive means.

DC motors are known for their torque/speed characteristics that are suitable for withstanding wide variations in torque, but this is only possible without a significant loss of speed as long as the power supply converter allows it, by maintaining a supply voltage o that is at least substantially constant as the current 0- absorbed by the motor rises.

For example, the power supply should be able to deliver, for a few seconds during the door locking operation, a current that is twice as high as the nominal supply current of the motor and, for very short M periods of a few tens of milliseconds while overcoming V 10 sticking points, a current that is four to six times M higher than the nominal current.

ci o The constraints on the motor power supply during the Ci door locking phase, or to overcome sticking points, leads to a consequent oversizing of the power supply unit, and especially the transformer for a conventional power supply, or leads to suppress or to by-pass the current control mechanism in the case of a switch-mode power supply, for example of the "fly-back" type, which could be dangerous.

A device supplied by an AC voltage, comprising an AC/DC voltage converter and a DC motor, is known from the document "MOSFET switch provides efficient AC/DC conversion" published in the review "Design Ideas" (Vol. 2119, February 17, 2000). The converter comprises a rectifier and a capacitor connected across the motor input terminals, this capacitor being charged by the rectified AC voltage through a switch controlled by a control circuit at the frequency of the rectified AC voltage.

From the patent US 6,061,259, a device for supplying power to a load from an AC voltage is known that comprises a varistor, a rectifier, an electronic switch and a capacitor connected across the terminals of the load. The conduction times of the electronic switch are calculated from the values of the output voltage, of the instantaneous input voltage and of the average input voltage. The device is thus protected against 0 severe interference on the input voltage. Since the h 5 current is designed to vary over a range from 0 to milliamperes, it is not capable of withstanding high current surges on its output.

q From the patent application EP 1 283 590, a device for supplying power to a load from an AC voltage is known that comprises a rectifier and a capacitor connected across the input terminals of the load, this capacitor being charged by the rectified AC voltage through a switch controlled by a control circuit at the frequency of the rectified AC voltage. The closure of the switch is triggered by the passage of the rectified AC voltage under a reference voltage level and the opening of the switch is controlled by the voltage across the terminals of the load.

From the patent application DE 33 04 759, an AC-DC converter device is known that comprises a switch controlled by an electronic unit as a function of various voltages sampled from a rectifier. The reference voltage that causes the switch to open is greater than that causing it to close.

These devices known from the prior art do not feature safety means that allow more or less temporary overloads resulting in a high output current to be managed, ensuring that the electronic components they comprise are not deteriorated.

Throughout the specification reference to any prior art is not, and should not be taken as an acknowledgement or any form of suggestion that the referenced prior art forms part of the common general knowledge in Australia.

SUMMARY OF THE INVENTION The aim of certain embodiments of the invention is to 0 0 provide a method for supplying power to an installation and h 5 an installation that allow the aforementioned drawbacks to be overcome and that provide an improvement with respect to the known methods and installations of the state of the art.

h In particular, the invention allows the oversizing of the V power supply means to be avoided.

S Accordingly in one aspect of the present invention there is provided a method for controlling an AC voltage power supply to an installation designed for the operation of a door of a building or of a gate and powered by an AC voltage, comprising an AC/DC voltage converter and a DC motor mechanically linked to the door or to the gate, the converter comprising a rectifier, a capacitor connected across the input terminals of the motor, this capacitor being charged by the rectified AC voltage provided through a switch controlled by a control circuit at the frequency of the rectified AC voltage, wherein the opening of the switch is triggered by the first of the two following events occurring the voltage across the terminals of the capacitor rising through a first voltage threshold, or another physical quantity exceeding another threshold, where this other threshold limits the current in the switch so as to protect it from current surges that could be damaging to it, while nevertheless authorizing a higher current than the normal current.

0 Suitably the closure of the controlled switch is O triggered by the rectified AC voltage falling below a second voltage threshold.

O

Preferably the event of exceeding another threshold by another physical quantity is the event of the rectified AC voltage rising through a third voltage threshold.

V The third voltage threshold may initially be higher

V)

M 10 than the second voltage threshold. Suitably the third y voltage threshold is modified by a control unit during the operation of the installation. Preferably the third voltage threshold is modified by the control unit after the opening of the controlled switch has been triggered by the rectified AC voltage rising through the third voltage threshold.

Preferably the event of exceeding another threshold by another physical quantity is the event of the conduction time of the controlled switch exceeding a duration time threshold. The duration time threshold may initially be greater than the conduction time of the controlled switch when the motor draws its nominal current.

Suitably the duration time threshold can be modified by the control unit during the operation of the installation. Alternatively the duration time threshold can be modified by the control unit after the opening of the controlled switch has been triggered by the conduction time of the controlled switch exceeding the duration time threshold. The time delay is preferably implemented between the opening of the switch triggered by the crossing of a threshold and the modification of the threshold. The delay time may be in the order of a few microseconds to a few seconds.

Suitably the third voltage threshold or the duration time threshold is returned to its initial value after a time delay. Preferably the return of the third voltage o threshold or the duration time threshold to its initial value is conditioned by the fact that, during this period, the opening of the controlled switch has not been triggered by the rectified AC voltage exceeding the third voltage threshold or the conduction time of the controlled switch exceeding the duration time threshold.

In another aspect of the present invention there is provided an installation designed for the operation of a door of a building or of a gate and powered by an AC voltage, comprising an AC/DC voltage converter and a DC motor mechanically linked to the door or to the gate, the converter comprising a rectifier, a capacitor connected across the input terminals of the motor, this capacitor being charged by the rectified AC voltage through a switch controlled by a control circuit at the frequency of the rectified AC voltage, wherein the control circuit is equipped with a control unit allowing the implementation of the control method discussed above.

BRIEF DESCRIPTION OF THE DRAWINGS The appended drawing shows an installation according to the invention and a method for controlling its power supply.

Figure 1 is a circuit diagram of the installation according to the invention.

Figure 2 is a flow diagram of a method for controlling the electrical power supply of the installation according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The installation 1 shown in Figure 1 is designed for 0 O the operation of a door GD of a building or of a gate.

The installation mainly comprises a power circuit 2 and a control circuit 3.

c In the power circuit, the AC line supply voltage represented by the phase line P and the neutral line N 1C 0 is rectified by full-wave rectification means REC. The output voltage of the rectification means allows the unidirectional charging of a capacitor CM through a controlled switch TR and means IL for limiting the o charge current of the capacitor CM.

o The controlled switch TR is, for example, an MOS-type transistor whose maximum operating voltage is at least c-i equal to that of the line supply.

Preferentially, the means IL allow the current intensity to be limited at the moment the controlled S 10 switch TR is closed. These means can comprise a simple en resistor or more complex circuit such as the primary of ci a 1:1 transformer whose secondary current is added, after rectification, to the charge current of the A capacitor CM.

A DC motor MOT is connected across the terminals of the capacitor CM during the phases where it is required to operate. It drives the gate or the door GD via a reducer gear and a mechanical link which are not shown.

Similarly, with the purpose of improving the clarity of the figures, the contactor circuit allowing the motor MOT to be supplied with one or the other polarity of the voltage UCM across the terminals of the capacitor CM is not shown.

The controlled switch TR is controlled by the control circuit 3. This circuit can base its control rule on the rectified line supply voltage V1 sampled just downstream of the rectification means REC and/or on the output voltage UCM. The rule can also depend on the voltage V2 sampled between the current limitation means IL and the controlled switch.

The circuit commanding the turning on or off of the controlled switch TR is represented symbolically by an RS flip-flop. The output Q of this flip-flop controls, for example, the gate voltage UG of a transistor.

A high state applied to the Reset input R causes the o flip-flop output Q to go low which turns off the (0 transistor TR. A high state applied to the input S O causes the flip-flop output Q to go high which turns on the transistor

TR.

ci 0A control unit UC, whose output are the inputs Set and Reset of the RS flip-flop has been shown symbolically.

M This control unit receives at least two signals from amongst the four signals shown: Vl, V2, UCM, Q.

en The control unit UC comprises at least one voltage comparator at the inputs CA1, CA2, CA3 (one or more O voltage references being used in order to compare the signals at these inputs). It can also comprise a timer circuit activated by the signal Q driving an input

TRIG.

With respect to the other known kinds of power supplies, the use of such a converter allows high currents to be delivered at a maximum, practically constant, voltage, the limit only being fixed by the characteristics of the controlled switch and the capacitance of the capacitor. And, it is known that a transistor that can be used as a controlled switch can withstand repetitive or occasional current surges that are higher or considerably higher than the average current.

A method for supplying electrical power to the installation is described with reference to Figure 2.

The closure of the controlled switch TR, represented by the step 11, is preferentially caused when the voltage of the rectified line supply falls below a voltage threshold VT, this passage through the threshold being detected during a test step Similarly, once the controlled switch is conducting, a o test step 12 is carried out in order to compare the 0- output voltage UCM (or V2 since the controlled switch o TR is conducting) with a threshold value VT2. The opening of the controlled switch TR is caused, during a step 14, as soon as the output voltage reaches this othreshold VT2.

An additional test step 13 is carried out in the case S 10 where the output voltage has not yet reached the en threshold voltage VT2. This test can relate to either ci the input voltage Vl or the conduction time of the controlled switch.

Ci If the result of the test is negative, the method loops back to step 13 or to step 12 (as represented by the dotted arrow on figure 2).

If the test relates to the input voltage Vl, it compares the latter to a threshold value VT3 higher than VT1. Since the threshold value VT3 is higher than the threshold value VT1, once the transistor TR becomes conducting, the current flowing through the controlled switch can be allowed to exceed its normal value, corresponding to the moment where the controlled switch TR goes from the open state to the closed state.

If the test relates to the conduction time TM of the controlled switch TR, it compares the latter with a duration time threshold value TT1 greater than the normal conduction time TT when the motor MOT draws the nominal current. Since the duration time threshold value TT1 is greater than the duration time threshold value TT, the current is allowed to exceed the nominal current. The conduction time TM is measured by measuring the activation time of the input TRIG of the control unit UC.

When the test is carried out on the input voltage and when it reaches the threshold VT3, it is clear that the 8 conduction time also exceeds the normal conduction time o TT corresponding to the nominal current flow to the 0- motor.

The voltage VT3 or conduction time TT1 thresholds are Spreferably adjustable dynamically. This dynamic omodification of the threshold is represented by the step 15 and is carried out by the control unit.

In 10 During initialization, the voltage threshold VT3 or the In en duration time threshold TT1 has a high value, for ci example authorizing an overcurrent equal to 5 times the nominal current. After the open command for the A controlled switch TR has been triggered by the input voltage Vl rising through the voltage threshold VT3 or by the conduction time TM of the controlled switch exceeding the duration time threshold TT1, the voltage threshold VT3 or the duration time threshold TTl may, in an optional step 15, be reduced to a lower value authorizing, for example, an overcurrent equal to twice the nominal current. This modification may be applied after an optional delay time of a few milliseconds, for example 20 ms.

The voltage threshold VT3 or the duration time threshold TT1 may be restored to the initial high value authorizing an overcurrent equal to 5 times the nominal current if, over a predetermined period (for example 3 during which the voltage threshold VT3 or the duration time threshold TTl authorizes an overcurrent equal to twice the nominal current, the opening of the controlled switch TR has not been triggered by the exceeding of either the voltage threshold VT3 or the duration time threshold TTI.

This reduction in either the voltage threshold VT3 or the duration time threshold TT allows overheating and destruction of the components, and in particular of the transistor providing the controlled switch function, to o be avoided.

o The succession of steps described allows the problems of short-lived or longer duration overloading raised c-i above to be solved.

Various modification procedures for the voltage threshold VT3 or the duration time threshold TT1 in 3 10 order to solve the overheating problems can be e envisioned. In particular, the thresholds could be ci allowed to take more than two voltage values or more than two duration time values. The combination of the A value of these thresholds and of their validity time depends especially on the thermal characteristics of the components. It can also be provided that the voltage threshold VT3 or the duration time threshold TT1 initially allow a very high overcurrent and then become lower than the voltage threshold VT1 or shorter than the duration time threshold authorizing the nominal current.

The whole or a part of the control unit and of the equivalent of the RS flip-flop can be integrated into a microcontroller, comprising comparators and a timer.

This microcontroller may, in addition, be given the job of managing instructions generated by a user.

Rather than using the voltage Vl, the pair of voltages V2 and UG could advantageously be used as control parameters for the state of the switch, the voltage V2 representing both the power supply voltage (when the switch is open) and the output voltage (when the switch is closed). In this case, only the inputs CA2 and TRIG of the control unit are used.

The installation and its method for supplying electrical power also allow the power consumption of the power circuit to be reduced to zero when the motor is not in use. This advantage is all the more important o since environmental standards and respect for the 0- environment require that the power consumption of o equipment in the standby or idle state be drastically limited.

ci oIn the specification the term "comprising" shall be understood to have a broad meaning similar to the term "including" and will be understood to imply the V) 10 inclusion of a stated integer or step or group of en integers or steps but not the exclusion of any other integer or step or group of integers or steps. This Sdefinition also applies to variations on the term S~"comprising" such as "comprise" and "comprises".

It is to be understood that the above embodiments have been provided only by way of exemplification of this invention, and that further modifications and improvements thereto, as would be apparent to persons skilled in the relevant art, are deemed to fall within the broad scope and ambit of the present invention defined in the following claims.

Claims

1. A method for controlling an AC voltage power o supply to an installation designed for the operation of a door of a building or of a gate and powered by an AC voltage, comprising an AC/DC voltage converter and a DC motor mechanically linked to the door or to the gate, the converter comprising a rectifier, a capacitor connected across the input terminals of the motor, this capacitor being charged by the rectified AC voltage y provided through a switch controlled by a control circuit at the frequency of the rectified AC voltage, wherein the opening of the switch is triggered by the first of the two following events occurring: the voltage across the terminals of the capacitor rising through a first voltage threshold, or another physical quantity exceeding another threshold, where this other threshold limits the current in the switch so as to protect it from current surges that could be damaging to it, while nevertheless authorizing a higher current than the normal current.

2. The method for controlling the power supply to an installation as claimed in claim 1, wherein the closure of the controlled switch is triggered by the rectified AC voltage falling below a second voltage threshold.

3. The control method as claimed in either claim 1 or claim 2, wherein the event of exceeding another threshold by another physical quantity is the event of the rectified AC voltage rising through a third voltage threshold.

4. The control method as claimed in claim 3, wherein the third voltage threshold is initially higher than the second voltage threshold.

The control method as claimed in either claim 3 or claim 4, wherein the third voltage threshold is +modified by a control unit during the operation of the 0 0 installation.

6. The control method as claimed in claim 5, wherein the third voltage threshold is modified by the control h unit after the opening of the controlled switch has V) been triggered by the rectified AC voltage rising through the third voltage threshold.

7. The control method as claimed in either of claim 1 or claim 2, wherein the crossing of another threshold by another physical quantity is the conduction time of the controlled switch exceeding a duration time threshold.

8. The control method as claimed in claim 7, wherein the duration time threshold is initially greater than the conduction time of the controlled switch when the motor draws its nominal current.

9. The control method as claimed in either claim 7 or claim 8, wherein the duration time threshold is modified by a control unit during the operation of the installation.

The control method as claimed in claim 9, wherein the duration time threshold is modified by the control unit after the opening of the controlled switch has been triggered by the conduction time of the controlled switch exceeding the duration time threshold.

11. The control method as claimed in either claim 6 or claim 10, wherein a time delay is implemented between the opening of the switch triggered by the crossing of a threshold and the modification of this threshold. S12. The control method as claimed in claim 11, wherein the delay time is 20 ms.

O h 5

13. The control method as claimed in any one of claims 6, 10, 11 or 12, wherein the third voltage threshold or the duration time threshold is returned to h its initial value after a time delay.

14. The control method as claimed in claim 13, wherein the return of the third voltage threshold or Sthe duration time threshold to its initial value is conditioned by the fact that, during this period, the opening of the controlled switch has not been triggered by the rectified AC voltage exceeding the third voltage threshold or the conduction time of the controlled switch exceeding the duration time threshold.

The control method as claimed in either claim 13 or claim 14, wherein the delay time is 3 s.

16. An installation designed for the operation of a door of a building or of a gate and powered by an AC voltage supply, comprising an AC/DC voltage converter and a DC motor mechanically linked to the door or to the gate, the converter comprising a rectifier, a capacitor connected across the input terminals of the motor, this capacitor being charged by the rectified AC voltage through a switch controlled by a control circuit at the frequency of the rectified AC voltage, wherein the control circuit is equipped with a control unit allowing the implementation of the control method as claimed in one of claims 1 to 0

17. A method for controlling the power supply to an installation substantially as hereinbefore described O O with reference to the accompanying drawings.

18. An installation for the operation of a door of a C building or of a gate, substantially as hereinbefore V) described with reference to the accompanying drawings.