AT525144B1 - Method and device for switching an electrical consumer - Google Patents

Abstract

In a method for switching an electrical load, such as a light bulb, in an electrical system that has an electrical load (13), electrical lines for the power supply (1) of the electrical load (3), a control circuit (12) for selectively or switching off the electrical load (13), a radio module (14) interacting with the control circuit (12) for wirelessly receiving a switching command for switching the electrical load (13) on or off, and a manually operated switch (15, 16) for selectively disconnecting or Connecting the electrical load (13) together with the control circuit (12) from or to the power supply (1), the manually operated switch (15, 16) is actuated to switch the electrical load (13) in order to interrupt the power supply of the electrical Consumer (13) and the control circuit (12) for a period of less than 5 sec., Preferably shorter than 2 sec., Esp especially shorter than 1 second, and the control circuit (12) is supplied with current during the current interruption from a chargeable energy store (4), such as a capacitor, and the current interruption is signaled at a control input (11) of the control circuit (12 ) is detected, so that the control circuit (12) switches the electrical load (13) when the current interruption is detected.

Description

Description

METHOD AND DEVICE FOR SWITCHING AN ELECTRICAL CONSUMER

The invention relates to a method and a device for switching an electrical load, such as a lamp, and an electrical system with such a switching device.

In particular, the invention relates to the switching of electrical loads in smart home applications in which the electrical loads can also be switched via network or radio interfaces. In such applications, the control circuit assigned to the electrical load must be constantly supplied with power in order to be able to receive and process control commands, e.g. via a radio interface.

[0003] Recently, smart home products have increasingly been offered, which can be installed in existing electrical systems, in which consumers are switched in the conventional manner by actuating a manual switch, which separates or restores the power supply to the electrical consumer. For example, illuminants are sold which can be used in existing illuminant sockets and have an integrated electronic control circuit and a radio module, via which the illuminant can be switched on and off by wireless control commands. The problem here is that in order for the electronic switching device integrated in the lamp to be ready for operation, it is necessary for the manually operated light switch built into the existing power supply system, such as a wall switch, to be permanently in the "on" position. A further problem lies in the lack of flexibility in actuation, since the switching process can only take place via the network or radio connection provided, in order to enable further accessibility of the device. The existing switching installations, such as the existing wall switches, lose their function.

The design of a switching relay with radio control described in patent specification DE102018108973 A1 has an energy store, but this is only charged when the output of the relay is switched on and a consumer is connected. The relay is not supplied with a neutral conductor and phase but with only one phase, which is why the energy for charging the energy store can only be provided by a voltage difference along this line caused by a resistor and for which the circuit must be closed, otherwise there is no voltage difference across the resistance is possible. If the relay and/or small energy storage device is rarely switched on, switching on by radio command is no longer possible. The switching command can also be given via a switch or button connected directly to the device, to specially provided connections, this would also be the only way to reactivate the device after the energy storage device has been completely discharged.

US 2017223807 A1 discloses several devices with radio control, some of which have energy storage, but not short-term energy storage to maintain the radio connection, but to continue operating the entire device in the event of a power failure or to operate a device without an external power supply. Specifically, two design variants of a smart lamp are listed, one for operation without a permanent supply, in this case the socket of the lamp only serves mechanical purposes, and one with integrated charging electronics to permanently maintain an energy store and, in the event of a failure of the supply from this, the draw energy to continue operating the device. With all of these devices, the switching commands can only be given by radio.

DN 212785960 U shows an LED driver circuit for operating an LED with AC voltage. However, this is only part of a currently standard smart lamp and the design of this circuit is also not expedient and is usually not used.

The invention therefore aims to overcome the disadvantages mentioned above and to create a switching method and a switching device with which the existing switching devices can also be used in the case of the installation of smart home devices.

To solve this problem, the invention provides, according to a first aspect, a method for switching an electrical load, such as a light bulb, in an electrical system, which has an electrical load, electrical lines for powering the electrical load, a control circuit for the optional Switching the electrical load on or off, a radio module that interacts with the control circuit for wirelessly receiving a switching command for switching the electrical load on or off, and a manually operated switch for selectively disconnecting or connecting the electrical load together with the control circuit from or to the power supply, wherein for switching the electrical load, the manually operated switch is actuated in order to interrupt the power supply of the electrical load and the control circuit for a period of less than 5 seconds., Preferably shorter than 2 seconds., Insbeso other shorter than 1 second, the control circuit is supplied with power during the power failure from a chargeable energy store, such as a capacitor, the power failure is detected at a control input of the control circuit and the control circuit switches the electrical load when the power failure is detected.

The invention thus consists in using a short power interruption, which is caused by the actuation of an existing switch, as a switching pulse for the control circuit. In addition to the existing wireless operating options, e.g. via radio, the corresponding devices can also be switched physically as usual using a wall switch.

In order for the control circuit of the electrical load to be switched to be able to recognize a short power interruption as a switching pulse, it requires a short-term energy store in order to remain active despite a lack of supply. The invention therefore provides that existing smart home devices, preferably smart home light sources, are provided with a short-term energy store provided for this function, e.g. in the form of a capacitor.

The manually operated switch can preferably be designed as a button, so that the power is interrupted by pressing the button.

Alternatively, the manually operated switch can be designed as a rocker switch with two stable end positions, the switching outputs of which are electrically bridged, the current being interrupted by moving the switch from one end position to the other, with the current flow being interrupted in an intermediate position between the two end positions .

In order not only to enable the electrical load to be switched on and off, but also to implement a dimming function, in particular in the case of lamps, a further preferred embodiment of the method provides that for dimming the electrical load, the manually operated switch must be switched on within a period of <5 sec., preferably <2 sec., is actuated at least twice in succession in order to bring about at least two interruptions in the power supply of the electrical load and the control circuit, which supplies the control circuit with electricity from a chargeable energy store, such as a capacitor, during the power interruptions the power interruptions are detected at a control input of the control circuit and the control circuit switches to a dimming mode when the power interruptions are detected. Provision can preferably be made here for the dimming process taking place in the dimming mode (rising and falling of the brightness) to be terminated by actuating the manually operated switch again, with the dimming state prevailing at the time of termination being permanently retained.

According to a second aspect, the invention provides a device for switching an electrical load, such as a lamp, comprising a control circuit that is or can be electrically connected to the electrical load for selectively

Switching the electrical load on or off, a radio module that interacts with the control circuit for wirelessly receiving a switching command for switching the electrical load on or off, the switching command being able to be fed to a first control input of the control circuit, the control circuit being designed to switch the electrical load on presence of the switching command at the first control input on or off, and further comprising electrical power supply connections for connecting the device to a power supply, the device further having a chargeable energy store, such as a capacitor, connected in parallel with the power supply, which is arranged around the control circuit to continue to be supplied with power without interruption in the event of an interruption in the power supply, and that the control circuit has a second control input which, in the event of an interruption to the current present at the power supply connections Power supply undergoes a change in potential that can be detected as a switching command, the control circuit being designed to switch the electrical load on or off when the switching command is present at the second control input.

The device preferably has an optocoupler which is connected to the second control input in order to electrically isolate the power supply from the second control input.

The energy store is preferably connected to the power supply with the interposition of an AC/DC converter.

The energy store is preferably connected to the power supply with the interposition of a voltage divider.

For the already mentioned dimming function, the control circuit can preferably be designed to switch to a dimming mode for the individual setting of the switching commands within a period of <5 sec., Preferably <2 sec brightness serves.

According to a third aspect, the invention provides an electrical system for operating an electrical load, such as a lamp, comprising an electrical load, a switching device according to the second aspect of the invention for switching the electrical load, to the power supply connections of the switching device connected electrical lines for the power supply of the electrical load and a manually operated switch for selectively disconnecting or connecting the electrical load together with the control circuit from or to the power supply.

The invention is explained in more detail below with reference to exemplary embodiments illustrated schematically in the drawing. 1 to 4 show different variants of the connection of a capacitor in a switching device, FIG. 5 shows an embodiment of a circuit for using a current interruption as a switching pulse for an electrical load, FIG Radio module, FIGS. 7 to 15 different variants of the integration of conventional hand-operated switches in the switching device and FIG. 16 a flow chart to show a dimming process.

As already mentioned, the control circuit of the electrical load requires a short-term energy storage device so that it can recognize a short power interruption as a switching pulse, in order to be able to function despite the lack of supply. Due to the possibly short charging time and the many charging cycles, capacitors (especially so-called ultracapacitors) are suitable energy storage devices for this purpose. In addition, capacitors are very cheap and available in many sizes. Various options for connecting a capacitor in a switching device are shown in FIGS. 1 to 4 .

Fig. 1 shows a power supply 1, which is formed in the present case from a conventional power supply of a household. The mains voltage of the power grid (e.g. 230 V) is converted by means of an AC/DC converter 2 into a direct voltage of e.g. 5V which is suitable for the operation of an electronic control circuit. In the case of a current interruption to be used as a switching pulse for switching the electrical consumer, a

Diode 3 connected capacitor 4 as a buffer, the capacitor 4 in parallel! is switched to power supply 1.

If the control circuit used can be operated with a voltage level of, for example, 5V, but is also functional down to a lower voltage level of, for example, 2V, the energy store or the capacitor 1, as shown in FIG the AC-DC converter 2 are connected in parallel. In this case, the capacitor 4 must be designed in such a way that within a period of time to be defined (e.g. 1.5 seconds), which corresponds to the maximum intended duration of the current interruption, the charge only decreases to such an extent that the lower voltage level is not undershot during this time .

A calculation example for the required capacitance of a capacitor which is connected as shown in FIG. 1 is given below. Assuming a time span to be bridged (tacıve) of 1.5 seconds, a minimum voltage (Vmin) of 2 V and an average current consumption (Aaverage) of the control circuit of 220 HA (with consumers switched off), the required minimum capacitance of 110 uF results for the capacitor 4:

_ A's AV Aaverage = 220 u4 Vanax = 5V Vmin = 2V Lactive tactive = 1.55 total = — A Ynax = 255

(Vmax —Vmin)

. Aaverage * Ctotal

F: = 110uF

Vinax [0025] Depending on the control electronics used, however, a multiple of the energy may be required, and a capacitor suitable for this purpose can be quite large. It can therefore make sense to use a more expensive "supercap"/ultra capacitor. However, such a capacitor is not very common with a voltage range of more than 2.7V.

For this reason, one can either interconnect several smaller-sized ultra-capacitors or it can also be advantageous to modify the circuit, as shown in FIG. In this case, a voltage divider is implemented by the resistors 5, with the control circuit being able to be operated at connection 6 with approx. 2 V and it being possible to use a capacitor with a nominal voltage of 2.6 V, for example. These are mainly used in the form of ultra-capacitors and are therefore available in many sizes and with various capacities.

The capacitor capacitance can then be calculated as follows. ace

F = — V Aaverage = 220 nA Voc = 2.6V VoeDe = 2V Lactive tactive = 1.55 Leotal = —actve___, Voc= 6.55

(Vpe-VpDepDo)

. Aaverage * Ctotal

F: = 286UF

Venax In this calculation example for FIG. 2, the required capacitance is 286 μF. The (silicon) Schottky diodes 3 planned in the circuit have a low voltage drop of less than 0.4V and can drop to a voltage drop of up to 0.1V with such small operating currents as here. Because of this, the voltage drop of the diodes in the

neglected above calculation example.

However, if a voltage of constant 5 V must be available at the output 6 for the operation of the control circuit and its periphery, an energy store 4 must be set after a rectifier 2 in such a way that a step-down converter (DC DC) 7 is switched, which then supplies the working voltage for the control circuit (e.g. 5 V). This is shown in fig.

If it makes sense for reasons of cost and/or space, the energy store 4 can also be connected between two step-down converters. For example, an AC-DC step-down converter can be used (in this case with 24 V on the output side) and then only a small DC-DC converter is required (in this case 5 V - 24 V on the input side with 5 V output ), which supplies a constant output voltage. Therefore, the voltage at the energy store can drop significantly more and the efficiency of the store is higher, which means that it can be designed (capacitively) smaller.

The capacitor capacitance can be calculated as follows in the embodiment according to FIG.

ps V Aaverage = 220 A VacDe = 24V Vpcoc = 5V tactive = 1.55 trotal = — active. Vacoc = 1.895 s

(Vacoe-Vpepc)

. Aaverage * Ctotal

F: = 83,368UF

Vinax

As can be seen in this calculation example, a capacitor installed according to the variant according to FIG. 3 requires less capacity in comparison to the variants according to FIGS. 1 and 2 with the same U bridging time period (tacıve). The higher the difference between the charging voltage of the capacitor (Vmax or Vacoc in this example) and the minimum output voltage (Vmin or VDCDC) at the end of the time period, i.e. the more percentage voltage loss the capacitor is allowed to have, the smaller its capacity can be can be selected, which of course also makes smaller sizes possible. However, the larger space requirement for the additional voltage converter should not be neglected.

In addition, in the variant shown in FIG. 3, a constant voltage is maintained within the period of time to be bridged by the energy store, which should be advantageous for some microprocessors.

Since there are capacitors that can also be used at a voltage of 100-230 V, an AC/DC converter with a low-voltage output can be dispensed with. In this case, a pure AC-DC conversion is sufficient, which can be implemented, for example, by a simple diode rectifier 8, as is the case in the embodiment according to FIG. This structure is particularly favorable, since such diode rectifiers are normally already present on the circuit boards of existing products - an AC-DC step-down converter in smart home devices is often not implemented using a purchased module, but rather using specially developed circuits and thus coupling directly after the rectifier is possible in these cases without great effort.

For other energy stores, however, it is sometimes necessary to lower the voltage level on the input side to a specific value. In such a case, this version cannot be used.

Fig. 5 shows an example of a circuit with which a control pulse for the control circuit is generated from a power failure of the power supply 1. So that the control circuit, which is constantly supplied as a rule, can recognize that the supply line to the electric

consumer was disconnected, it needs a signal at pin 11 of its microprocessor, which must be minimized to the low voltage level of the processor. This is achieved through the use of an optocoupler 10.

However, the use of an optocoupler is not necessary in the circuits shown in FIGS. 1 and 2, since the voltage level here before the capacitor is already low enough. In the variant according to FIG. 3, the level can also be lowered to the correct voltage level with a voltage divider, if necessary.

Pin 11, at which the processor detects the loss of supply, should, if possible, be an interrupt pin in order to be able to react as quickly as possible and to very short power interruptions.

6 shows the schematic structure of a smart lamp circuit. The microcontroller (UC) 12 represents the control circuitry of the device and therefore must be powered at all times. The LED circuit 13 (often also called LED driver) does not require any current during the physical switching command by actuating the manually operated switch, since the input voltage for supplying the LEDs is not available anyway. Likewise, the radio module 14 does not necessarily require electricity, since it is very unlikely that a physical switching command and a switching command by radio will be given at the same time. However, supplying the module can be an advantage if restarting the module would take a long time. If this is the case, it shouldn't be a problem if the radio command is ignored or implemented later. However, depending on the radio module, it may be necessary to supply the radio module permanently, since some modules sometimes need a while to restart after a power failure and this could lead to disadvantages.

7 to 13 show different ways of arranging manual switches in an electrical installation for an electrical load, in particular a lamp. It is important that, due to the nature of wall switches and wall push-buttons, "rushing" (frequent and irregular switching on and off during the switching process) can occur when switching. In order to avoid the control circuit interpreting this as a large number of switching pulses, it can be useful to buffer/smooth the voltage at feedback pin 11 of the processor. This can be solved, for example, with a very low-capacitance capacitor.

7 shows a circuit with a power supply 1 and an electrical load 13, such as a light bulb. In the circuit, a mechanical switch 15 is provided, which can be switched back and forth between two switching positions in order to switch the load on or off.

Fig. 8 shows a modified embodiment, in which two switches 16 are arranged in a so-called. Alternating circuit in the circuit.

Fig. 12 shows a modified embodiment, in which two changeover switches 16 and one or more cross switches 22 are arranged in a so-called cross circuit in the circuit.

The circuits shown in FIGS. 7, 8 and 12 are the most common wiring variants in households worldwide.

If you don't want to or are not allowed to make any changes to the electrical installation, you can still take advantage of the invention by causing the current interruption to be used as a switching pulse by switching the switch 15 or 16 twice within a short period of time.

[0046] However, the maximum period of time for which the device is designed may lie between switching back and forth. A few seconds can make sense here.

If it is possible and / or desired, a hand-operated switch 15 or 16 can easily be bridged with a short piece of wire. It is irrelevant whether the existing electrical installation is a simple circuit, an alternating circuit or even one

cross circuit acts. Bridging a single switch is sufficient in any case. 9 shows an embodiment according to FIG. 7 with an additional U-bridge 17. FIG. 10 shows an embodiment according to FIG. 8 with an additional U-bridge 17 for one of the two changeover switches 16. FIG additional bridging 17 in one of the changeover switches 16. Here, the current interruption occurring when switching between the two end positions of the switch is used as a switching pulse.

In the case of simple circuits of the type shown in FIG. 7, it is also possible to replace this with a button 18, as shown in FIG. The advantage of this design compared to the U-bridging of the switch is that the button 18 always stays in the same position after switching.

Fig. 14 shows a circuit in which the switching of the consumer takes place by means of a surge circuit with a plurality of buttons 19, which actuate a relay 20, which controls the switch 21. As shown in Fig. 15, the jumper wire 17 must be wired in front of the relay in the control cabinet, i.e. at the two inputs of the relay switch contact, not at the inputs of the coil.

16 shows a flow chart for representing a dimming process triggered by actuating the manually operated switch, e.g. a button. In step S1, a switching pulse is triggered by pressing the switch or button, which triggers a timer. If within a defined time interval of e.g. 2 sec. a second switching pulse is triggered in step S2, the process continues with step S3.

[0051] Otherwise, the process starts from the beginning and awaits step S2 again. In step S3, the dimming process is carried out until, in step S4, another switching pulse is detected by actuating the switch or button. The dimming state present at the switching time is then maintained in step S5.

Claims (12)

patent claims 1. A method for switching an electrical load, such as a light bulb, in an electrical system that has an electrical load (13), electrical lines for the power supply (1) of the electrical load (13), a control circuit (12) for the optional or switching off the electrical load (13), a radio module (14) interacting with the control circuit (12) for wirelessly receiving a switching command for switching the electrical load (13) on or off, and a manually operated switch (15, 16) for selectively disconnecting or Connecting the electrical load (13) together with the control circuit (12) from or to the power supply (1), wherein the manually operated switch (15, 16) is actuated to switch the electrical load (13) in order to interrupt the power supply of the electrical load (13) and the control circuit (12) for a period of less than 5 sec., Preferably shorter than 2 sec., Esp especially shorter than 1 second, the control circuit (12) is supplied with power from a chargeable energy store (4), such as a capacitor, during the power interruption, the power interruption is detected at a control input (11) of the control circuit (12). and the control circuit (12) switches the electrical load (13) when the power interruption is detected. 2. The method according to claim 1, characterized in that the manually operated switch (15, 16) is designed as a button (18) and the current interruption is brought about by pressing the button (18). 3. The method according to claim 1, characterized in that the manually operated switch (15, 16) is designed as a rocker switch with two stable end positions, the switching outputs of which are electrically bridged (17), and the current interruption is brought about by switching the switch from one end position to the other is, the current flow is interrupted in an intermediate position between the two end positions. 4. The method according to claim 1, 2 or 3, characterized in that for dimming the electrical load (13), the manually operated switch (15, 16) is actuated at least twice in succession within a period of <5 seconds, preferably <2 seconds in order to bring about at least two interruptions in the power supply of the electrical load (13) and the control circuit (12), the control circuit (13) is supplied with power during the power interruptions from a chargeable energy store (4), such as a capacitor, which Current interruptions are detected at a control input (11) of the control circuit (12) and the control circuit (12) switches to a dimming mode when the current interruptions are detected. 5. Device for switching an electrical load, such as a lamp, comprising a control circuit (12) that is or can be electrically connected to the electrical load (13) for selectively switching the electrical load (13) on or off, a radio module that interacts with the control circuit (14) for wirelessly receiving a switching command for switching the electrical load (13) on or off, the switching command being able to be fed to a first control input of the control circuit (12), the control circuit (12) being designed to switch the electrical load (13) switched on or off when the switching command is present at the first control input, and further comprising electrical power supply connections for connecting the device to a power supply (1), characterized in that the device also has a chargeable energy store (4), such as a capacitor, connected in parallel with the power supply , exhibits, the aneo is arranged to supply the control circuit (12) with power when the power supply is interrupted, and that the control circuit (12) has a second control input (11) which, when the power supply present at the power supply connections is interrupted, undergoes a change in potential which can be detected as a switching command, wherein the control circuit (12) is designed to switch the electrical load (13) on or off when the switching command is present at the second control input (11). 6. Device according to claim 5, characterized in that the device has an optocoupler (10) which is connected to the second control input (11) in order to electrically isolate the power supply (1) from the second control input (11). 7. Device according to claim 5 or 6, characterized in that the energy store (4) is connected to the power supply (1) with the interposition of an AC/DC converter (2). 8. Device according to claim 5, 6 or 7, characterized in that the energy store (4) is connected to the power supply (1) with the interposition of a voltage divider (5). 9. Device according to one of claims 5 to 8, characterized in that the control circuit (12) is designed to switch to a dimming mode within a period of <5 seconds, preferably <2 seconds, when at least two switching commands are present switch. 10. Electrical system for operating an electrical load, such as a lamp, comprising an electrical load (13), a switching device for switching the electrical load (13) according to one of claims 5 to 9, electrical lines connected to the power supply connections of the switching device for Power supply for the electrical consumer (13) and a manually operated switch (15, 16) for selectively disconnecting or connecting the electrical consumer (13) together with the control circuit (12) from or to the power supply (1). 11. Plant according to claim 10, characterized in that the manually operated switch (15, 16) is designed as a button (18). 12. System according to claim 10, characterized in that the manually operated switch (15, 16) is designed as a rocker switch with two stable end positions, the switching outputs of which are electrically bridged (17), with a switch from one end position to the other in an intermediate position between the two end positions, a current flow through the switch can be interrupted. 6 sheets of drawings