Lighting system for tunnel or similar structures

A lighting system for tunnels or similar works. The lighting system with LED diodes, including at least one lighting strip with LED diodes, with at least one set of LED diode modules, the modules of a set being divided up into subsets of one or more modules supplied with power by respective power supply buses, an electronic system supplying power to the strip, making it possible to power up, according to a first mode of operation, all the power supply buses and, in a second mode of operation, only a part of the power supply buses, so as to reduce the electrical consumption of the strip.

TECHNICAL FIELD AND BACKGROUND

The present invention relates to a lighting system with LED diodes.

The use of lighting strips with LED diodes is expanding because of their light efficiency and ease of installation.

An LED diode strip typically comprises a flexible printed circuit bearing LED diodes, disposed inside a flexible jacket made of plastic material, transparent at least in the zone covering the LED diodes to allow the light to exit.

The LED diodes are arranged in identical modules which are repeated along the strip, all the modules being supplied with power by a common power supply bus with two electrical conductors, under the same power supply voltage. The power supply bus extends over the entire length of the strip, so as to allow the strips to be connected together one after the other.

Conventionally, the strip is supplied with power by a non-filtered double-alternating rectified voltage, from the mains, or, for the shorter strips, by a DC voltage such as 24 V DC.

The strips are generally installed in subways such as tunnels, but can also light parking lots, staircases, etc.

Backup battery operation is generally provided for mains outage cases.

The need to maintain emergency lighting for sufficient time generally imposes the use of high-capacity batteries, that are bulky and heavy.

Furthermore, in some situations, the lit zone is deserted, and would not need to be lit so intensely, which would make it possible to save energy.

SUMMARY

The invention aims to remedy these problems and its subject is a lighting system with LED diodes, comprising:at least one lighting strip with LED diodes, with at least one set of LED diode modules, the modules of a set being divided up into subsets of one or more modules supplied with power by respective power supply buses,an electronic system supplying power to the strip, making it possible to power up, according to a first mode of operation, all the power supply buses and, in a second mode of operation, only a part of the power supply buses so as to reduce the electrical consumption of the strip.

By virtue of the invention, it is possible to reduce the electrical consumption of the strip while producing light, which makes it possible to save on the capacity of the backup battery. Furthermore, in the other situations in which it is not necessary to supply maximal lighting, for example in the absence of personnel on the lit site, the electrical consumption can be reduced without in any way ceasing to light the site for security reasons.

The set of modules can comprise one module supplied with power by a respective power supply bus and at least one other module supplied with power by another power supply bus. Preferably, the set of modules comprises one module supplied with power by a respective power supply bus and all the other modules of the set are supplied with power by a same other power supply bus. That makes it possible to reduce the number of electrical conductors needed to supply power to the strip. For example, in reduced lighting, there is 1 module in every 2, 1 module in every 3, 1 module in every 4, even 1 module in every 6 or 1 in every 8, which remains on, depending on the result expected for the reduced or “emergency” lighting. Each set of modules can comprise between 2 and 20 modules, better between 2 and 10 modules, even better between 2 and 5 modules. The choice of the number of modules can be made notably as a function of the length of each module, so that, in the mode of operation with reduced lighting, the spacing between the modules supplied with power along the strip nevertheless produces sufficient lighting.

Each module comprises, for example, between 30 and 100 LED diodes. All the modules need not be identical to one another. For example, the module intended to be supplied with power permanently can comprise LED diodes supplied with an electrical power very much lower than their nominal power, for example more than two times lower, so as to prolong the life of the diodes given the permanence of the power supply. The modules can have different printed circuits, as necessary. Preferably, the lighting level is uniform between the modules in maximum lighting.

The modules of the same set are preferably disposed one after the other along the strip. The length of a module can usually lie between 25 and 100 cm. The modules can even correspond to rows of LED diodes extending along the strip. For example, the first module corresponds to a first row, and the other modules to the other rows. It is even possible to have an arrangement of the modules along the strip that is more complex, with, for example, printed circuits bearing several rows of LED diodes, the module that is on during the reduced lighting corresponding to only a part of the rows of only a part of the printed circuits.

The system can comprise at least one human presence sensor (via an infrared, radar or other detection), and the switch from the first mode of operation to the second and vice versa being made also according to whether or not a human presence is detected. For example, the system comprises an active RFID beacon sensitive to the proximity of an active RFID badge worn by the personnel of a site, and the change of mode can be made as a function of the distance at which the badges are detected. It is also possible to have simply a clock, which controls the switch to reduced lighting at certain times.

The strip can comprise a quick connector to at least three conductors, including a common conductor and at least two conductors specific to respective subsets of modules.

Another subject of the invention is a lighting strip for a system according to the invention, as defined above, comprising:a flexible jacket,at least one set of LED diode modules disposed inside the flexible jacket and being repeated for example along the latter, the modules of a set being divided up into subsets of one or more modules supplied with power by N respective power supply buses,a connector having at least N−1 poles, making it possible to supply power respectively to said buses.

Yet another subject of the invention is a method for lighting a work, notably a tunnel, in which a system according to the invention is used by supplying power simultaneously to all the modules from the mains to maximally light the work, and by supplying power only to a part of them in power outage cases or when there is a lesser need for light.

DETAILED DESCRIPTION

FIG.1shows a lighting system1according to the invention, comprising a strip10intended to light a tunnel for example.

The strip10comprises, as can be seen inFIG.2, a flexible jacket50, for example made of silicone, inside which is disposed a flexible printed circuit51bearing LED diodes52.

The LED diodes are arranged according to a succession of identical sets P1, P2, etc. Each set Pk of modules, with k an integer lying between 1 and the total number of sets of the strip, comprises at least two subsets of modules M1and M2.

In the example considered, the subset M1comprises a single module11and the subset M2comprises three modules12,13and14.

All the modules11of the strip are supplied with power by the same power supply bus20,21. Thus, at the terminals of each of them, there is the same power supply voltage, for example approximately 200 V DC average voltage, when the voltage corresponds to the double alternation rectification of the 230 V AC mains, the invention not being limited to a particular power supply.

All the other modules are supplied with power by another power supply bus20,22, the conductor20being common to both buses. Thus, each of the modules12,13and14receives the same power supply voltage, for example approximately 200 V DC average voltage.

The conductors20,21and22are linked at one end by a plug connector60to an electronic power supply system30which is itself connected to the mains, for example 230 V AC as illustrated, but other mains voltages are possible, for example 110 V AC, or DC voltages such as 24 V DC.

The strip10can have the same type of connector, male or female, at the other end, so as to allow several strips to be connected together one after the other.

The electronic power supply system30is arranged to supply power respectively to one or more of the buses according to the mode of operation sought.

In the example considered, in a first mode of operation, corresponding to maximal lighting, the power supply buses20,21on the one hand, and20,22on the other hand, are supplied with power, for example under the same double-alternating rectified DC voltage.

The bus20is for example linked to the − and the buses21and22are linked to the +, at the output of a diode bridge used to produce the power supply DC voltage. All the modules11to14are on.

The second mode of operation corresponds to the supply of power by a backup electrical source40, comprising, for example, an electric battery and an associated inverter, if necessary.

The switch to this second mode of operation takes place for example in network outage cases.

The power supply system30is arranged to supply power only to the bus20,21in this second mode of operation, such that only the modules11are on along the strip.

The electrical consumption of the strip is then reduced, and the latter supplies minimal lighting.

The power supply system30comprises, for example, an electromechanical relay which is supplied with power by the 230 V AC mains and which, when supplied with power, ensures the connection of all the buses20,21and22to the rectifier bridge. In network outage cases, this relay switches to an idle state in which it ensures the connection of only the bus20,21to the backup source40.

The power supply system30can then switch, in one exemplary implementation of the invention, to a mode of operation in which only the bus20,21is supplied with power, but by the mains instead of the backup source.

The switch to this mode of operation takes place for example in certain circumstances in which the mains is present but in which the need for lighting is lower, for example because of the absence of personnel on the site lit by the strip.

The power supply system30can receive a control signal from a detector80which is sensitive to the presence of people within a given perimeter; if no person is detected, the system switches to reduced lighting; in case of human presence, it switches back to normal lighting mode.

The dispositions of the modules on the strip can be different, and each module can correspond, for example, to a row of LED diodes, all the rows extending in parallel along the strip, as illustrated inFIG.3.

In this figure, the strip comprises a subset M1of modules corresponding to a row of LED diodes extending over the entire length of the strip, the rest of the LED diodes forming a second subset M2of modules. In reduced lighting, only the row corresponding to the subset M1is on. When the lighting is maximal, all the rows are supplied with power.

It is even possible to have, as illustrated inFIG.4, a disposition of the LED diodes in the form of several rows, three for example, belonging to sets P1, P2, etc., which are repeated along the strip, the grouping of the LED diodes within the strip in the form of subsets of modules controlled by respective power supply buses being such that, in reduced lighting, only a part of the rows is on, and only over a part of the length of each set. In the example illustrated inFIG.4, only the subset M1within the sets P1, P2, etc. of modules which are repeated along the strip is on in reduced lighting.

The number of modules within a set Pk of modules can also be different, as can the number of modules in each subset, the number of subsets, and the number of sets.