LED light fixture and indoor lighting system with high fidelity control of the luminous flux

Abstract

The invention relates to an LED light fixture having a digital interface (Pi / o) receiving a digital light command (CNL) and means (CLC) for converting the command into a digital current command (CC). The light fixture has a light-generating channel (CN) commanded by the digital current command and comprises a group of diodes (GD) connected in series, digital-to-analogue conversion means (CFC, CNA, RN) receiving the digital current command and producing an analogue current command (C_ID), and a direct current generator (GC) supplying the group of diodes with a direct supply current (ID) whose intensity is dependent on the analogue current command. According to the invention, the digital-to-analogue conversion means produce the analogue current command with a quantisation step that increases when the digital current command increases. Figure 5

Description

LED Diode Luminaire and Interior Lighting System with High-Fidelity Control of Luminous Flux

[0001] The present invention relates generally to interior building lighting. More particularly, the invention relates to a light-emitting diode (LED) luminaire equipped with high-fidelity control means for the luminous flux. The invention also relates to a dynamic interior lighting system comprising at least one LED luminaire as mentioned above. The invention finds a preferred, but not exclusive, application in interior lighting systems that deliver a luminous flux mimicking daylight.

[0002] In recent years, the lighting industry has seen significant technological advancements with the emergence of LED lighting devices, which are more energy-efficient than traditional lighting and provide higher-quality artificial light. LED luminaires are capable of producing light with spectral characteristics close to those of natural white light, offering users unprecedented levels of visual comfort.

[0003] Natural light is a key contributor to visual comfort. It plays a crucial role in our health and well-being, notably by helping to regulate our biological clock, stimulate vitamin production, and improve our mood and energy levels. Therefore, the daylight factor, or "DF," is a widely used indicator, particularly among the scientific community and architects, and is taken into account by various standardization and labeling systems.

[0004] LEDs are characterized by a luminous flux that is roughly proportional to the current flowing through them. The arrangement of LEDs connected in series and carrying the same current is common in LED luminaires. This configuration offers the advantage of simple and simultaneous current control of multiple LEDs. LEDs with similar characteristics are connected and, when powered by the same current, provide a uniform luminous flux.

[0005] In the prior art, pulse width modulation (PWM) has become the standard for controlling the average current in LEDs. This switching control technique allows for adjustment of the average current and regulation via control of the duty cycle of a pulse train. PWM control is frequently used for dimming the light intensity emitted by LED luminaires.

[0006] The inventive entity believes that interior lighting systems with high-fidelity control of luminous flux are poised for significant growth in the coming years. The availability of robust and cost-effective technology is essential for the widespread adoption of these systems.

[0007] An interior lighting system with high-fidelity control of luminous flux is a system capable of reproducing daylight in its spectral components, brightness, and dynamics. Such a system creates the illusion of a more transparent space, with more windows. The illuminated space then appears to have a perceived daylight factor that is higher than its actual daylight factor.

[0008] The human eye has a wide dynamic range of sensitivity to light, with a ratio of 1 / 106, adapting equally well to sunlight of 100,000 lux in summer and moonlight of 0.1 lux. For the illusion of natural light to work, daylight must be faithfully reproduced by the lighting system. Accurately reproducing the variability of daylight due to the daily cycle, as well as cloud cover and other factors, is crucial. With insufficient dynamic range, the eye perceives jumps in brightness, resulting in a less than satisfactory user experience. The color of the light must also be faithfully reproduced. To achieve this, luminous flux from different light sources must be precisely measured to obtain the appropriate color mix, given that the human eye has a sensitivity of up to 0.5 MK-1 in its color perception.

[0009] In digital technology, to linearly cover a dynamic range from 0.1 lux to 100,000 lux, with an accuracy of, for example, 0.1 lux, at least 10⁶ different numerical values ​​are required. In binary, 20 bits allow for the 2 20 = 1048576 different numerical values. At least 20 bits are needed in this example to represent the aforementioned dynamics.

[0010] The "PWM" modulation control solutions known in the field of lighting generally offer 8-bit digital control, or 2 8 =256 discrete values ​​available for control. In the field of home automation, 16-bit "PWM" commands are known, i.e. 2 1665,536 discrete values ​​are available. These earlier techniques based on PWM modulation are limited in terms of accuracy over a wide dynamic range and are unsuitable for the need described above. Furthermore, the PWM pulse train frequency drops below 20 kHz with 16-bit control, which can cause interference in the audible band and / or with the pixel scan frequencies used in video displays. Electromagnetic interference with switched-mode power supplies and electromagnetic compatibility (EMC) issues can also occur with PWM modulation. Excessive switching frequencies can lead to a loss of linearity in LEDs, particularly due to their on-time, and degraded response from other semiconductor components in the circuits.Furthermore, LED diodes are subjected to increased stresses in switching mode, particularly thermal stresses, which have the effect of reducing their lifespan.

[0011] Analog current control in an LED diode has the advantage of not having the aforementioned disadvantages.

[0012] In his technical article entitled "Hybrid Wide Dimming Ratio Linear LED Current Controller Using LT8614 & LT3083 / LT6015," published on October 17, 2016, in the "Resource Library" of the American company ANALOG DEVICE®, Thomas Mosteller disclosed an electronic circuit for analog current control in an LED. This circuit implements a DC-DC voltage converter, an operational amplifier, and a MOSFET transistor, and allows for precise analog control of the LED current.

[0013] A digital-to-analog converter, or DAC, is necessary to control a series of LEDs in a luminaire using analog current from a digital interface. As mentioned earlier, to linearly cover the entire daylight spectrum with high accuracy, a very large number of different digital values ​​are required. A 24-bit DAC would be necessary for high-fidelity control of an indoor lighting system that reproduces daylight. The price of a DAC depends on its number of bits. Integrating a 24-bit DAC into an LED luminaire significantly increases the overall cost.

[0014] The present invention aims to provide a technical solution to the problems detailed above and proposes a new approach enabling the design at an optimal cost of "LED" diode luminaires and interior lighting systems capable of delivering a luminous flux copying daylight.

[0015] According to a first aspect, the invention relates to a light-emitting diode luminaire, known as "LED", of the type having a digital interface receiving a digital light control and means for converting the digital light control into at least one digital current control, the luminaire having at least one light production channel controlled by the digital current control, and the light production channel comprising a group of light-emitting diodes connected in series, digital-to-analog conversion means receiving the digital current control and producing in response a corresponding analog current control and means for generating direct current supplying the group of light-emitting diodes with a direct supply current whose intensity is a function of the analog current control.According to the invention, the digital-to-analog conversion means are arranged to produce the analog current control with a quantization step that increases as the value of the digital current control increases.

[0016] According to a particular embodiment of the luminaire according to the invention comprising at least two light-producing channels, the digital light control includes brightness and color information, and the digital light control conversion means convert it into at least two digital current commands which are supplied respectively to the two light-producing channels for the control thereof.

[0017] According to a particular feature of the invention, in a light-producing channel, the digital-to-analog conversion means comprise binary format reduction means, a linear-type digital-to-analog converter, and analog-level restoration means, the binary format reduction means having at least two ranges jointly covering a full dynamic range of values ​​of the digital current control, a first range and a second range being associated respectively with low and high values ​​of the digital current control, and the range of values ​​covered by the second range being wider than that of the first range, and, in each of the ranges, the digital current control being represented by a calibrated digital current information and a range indication information,and the calibrated digital current information having a predetermined number of bits equal to that of the digital-to-analog converter and less than the number of bits of the digital current control.

[0018] According to another particular characteristic, the means of binary format reduction include three calibers.

[0019] According to yet another particular characteristic, the digital-to-analog converter is a 16-bit converter.

[0020] According to yet another particular feature, the analog level restoration means include a switchable resistive voltage divider bridge which is controlled in switching by the range indication information so as to establish a voltage division ratio which corresponds to an applied range indicated by the range indication information.

[0021] According to yet another particular characteristic, in the light production channel, the means of generating direct current include a DC-DC type voltage converter and a voltage-controlled current generation circuit.

[0022] According to yet another particular characteristic, the voltage-controlled current generation circuit is of the so-called "current well" type and includes an operational amplifier and a transistor of the so-called "MOSFET" type.

[0023] According to another particular embodiment of the invention, in the light production channel, the digital-to-analog conversion means include a logarithmic type digital-to-analog converter.

[0024] The invention also relates to an interior lighting installation comprising at least one luminaire, as briefly described above, installed in a building, a light sensor installed outside the building and exposed to daylight, wired and / or wireless information transmission links and control means, the control means being in communication, via the links, with the sensor and the luminaires and controlling them from light information provided by the sensor and control information transmitted by a user via a human-machine communication means.

[0025] Other advantages and features of the present invention will become more apparent upon reading the detailed description below of several particular embodiments of the invention, with reference to the accompanying drawings, in which:

[0026] La is a curve showing the brightness perceived by a human eye compared to the measured brightness.

[0027] Laest is a general diagram showing a first architecture for controlling a group of LED diodes in a luminaire according to the invention.

[0028] Laest is a general diagram showing another architecture for controlling a group of LED diodes in a luminaire according to the invention.

[0029] This is a diagram illustrating, using a theoretical example, the operating principle of controlling a group of LED diodes in the architecture of the.

[0030] Laest is a simplified electronic diagram of a luminaire according to the invention designed with the architecture of laet having a single light production channel.

[0031] Laest is a simplified electronic diagram of a luminaire according to the invention designed with the architecture of laet having two light production channels.

[0032] This is a simplified block diagram of an interior lighting system according to the invention designed to provide lighting that mimics daylight.

[0033] Lamontre schematically provides an example of the deployment of the system in a residential building.

[0034] In general, the invention takes advantage of the fact that the human eye's perception of brightness is not linear with respect to the brightness level, as illustrated by the curve showing perceived brightness (LP) as a function of measured brightness (LR). The sensitivity of the human eye is logarithmic and decreases significantly at high brightness levels. Thus, for example, the human eye will easily distinguish a brightness variation from 0.2 lux to 0.4 lux, but will have more difficulty distinguishing a brightness variation from 200 lux to 210 lux. The inventing entity has deduced from this that it is not necessary to maintain a constant resolution across the entire brightness range of the reproduced light to provide the user with a fully satisfactory natural light experience.With this approach, it becomes possible in a luminaire of the invention to use a digital-to-analog converter with a reduced number of bits to control the LED diodes with analog current from a digital interface of the luminaire.

[0035] In general, in the various examples and forms of implementation described below, components and information with similar references are components and information with similar characteristics and / or functionalities and will not be systematically specified.

[0036] Lamontre schematically represents a luminaire of the invention LU1 having a first architecture of control means MC1 to control a direct current generator GC ensuring the electrical supply of a group GD of LED diodes connected in series.

[0037] The MC1 control means here essentially comprise two functional blocks: CLC and CNA. LOGThe CLC and CNA functional blocks LOG They jointly perform a conversion of a digital light control CNL into an analog current control C_ID, which is applied to a control input of the current generator GC. The C_ID control applied to the input of the current generator GC results in a continuous supply current ID flowing through the diode group GD, this current ID having an intensity proportional to the value of the C_ID control.

[0038] The CLC function block receives the CNL digital light command as input and translates it into a DC digital current command using a calibration function. This calibration function, typically obtained through prior measurements, is stored in the CLC function block and provides information, via the delivered DC digital command, on the current ID to be supplied to the diode group GD to produce light with the lux luminance requested by the CNL command.

[0039] The CNA functional block LOG In this architecture, it is a logarithmic digital-to-analog converter. The DAC converter LOG The DAC receives the DC digital current command as input and delivers the C_ID analog current command as output, which is supplied to the GC current generator. LOGIt operates with a quantization step that increases as the value applied to its digital input increases, resulting in a reduction of the resolution of the corresponding value supplied to its analog output. This is how the DAC works. LOG allows for a reduction in its number of bits compared to what would be required with a linear digital-to-analog converter. Thus, for example, considering a 24-bit digital lighting control (DLC) system, a DAC LOG 18 bits will be sufficient to obtain the analog current control C_ID.

[0040] Lamontre schematically illustrates a luminaire of the invention LU2 having an alternative control means architecture MC2 for controlling the current generator GC, which supplies power to the diode group GD. This alternative architecture is described below, also with reference to the diagram which illustrates the operating principle through a theoretical example.

[0041] As can be seen in the figure, the MC2 control means here essentially comprise the aforementioned CLC function block, a CF_CNA function block and an RN analog level recovery circuit which together perform the conversion of the CNL digital light control into the C_ID analog current control.

[0042] The CF_CNA function block receives as input the DC digital current command delivered by the CLC function block, corresponding to the CNL digital light command. The CF_CNA function block outputs a current command comprising an ICa calibrated analog current command and a CL calibrated indicator signal. The CF_CNA function block essentially comprises a CFC binary format reduction function and a CDA digital-to-analog converter.

[0043] The binary format reduction function (CFC) reduces the binary format of the control signal by introducing ranges and using the same reduced number of bits to represent the value in each range. The range used is determined by the CFC function based on the value of the CC control signal. Each range corresponds to a specific quantization step and therefore a specific resolution, as will become clearer later. The CFC function outputs a current control signal (CNC) comprising a calibrated current signal (IC) and the corresponding range indication signal (CL), which indicates the active range. The calibrated current signal (IC) has a significantly lower number of bits than the CNL and CC control signals. The IC signal is fed into the DAC.The CL gauge indication information is provided to a switching control input of the RN analog level recovery circuit. The CFC format reduction function is typically performed by calculation and / or with the aid of mapping.

[0044] The DAC is a linear type, typically a commercially available DAC compatible with the target cost of the LU2 luminaire. The DAC delivers the calibrated analog current control ICa in response to the input digital information IC. The DAC has a number of bits equal to that of the digital information IC delivered by the binary format reduction function CFC. The analog control ICa is fed as input to the analog level recovery circuit RN.

[0045] The analog level restoration circuit RN is formed from a switchable resistive voltage divider bridge. Electronic switches, controlled by bits C0 and C1 of the range indication information CL, allow setting the voltage division ratio of the RN circuit. The analog current control C_ID is generated in the RN circuit by adjusting the level of the analog control ICa using a level adjustment factor FA. The value of the applied adjustment factor FA is determined by the voltage division ratio selected in the RN circuit. Therefore, the value of the adjustment factor FA corresponds to the range indicated by the range indication information CL and applied by the binary format reduction function CFC.

[0046] In the theoretical example considered here and illustrated in the following:

[0047] The CNL digital lighting control provides a setpoint from 0 to 10 5lux on 24 bits, which is translated into a 24-bit DC current digital control from 0 to 3500 mA by the CLC function block.

[0048] The CFC binary format reduction function uses CA0, CA1, and CA2 ranges. These ranges are defined as 0 to 20 mA, 20 to 300 mA, and 300 to 3500 mA, respectively, and correspond to luminance ranges of 0 to 571 lux, 571 to 8571 lux, and 8571 lux to 10 5 lux. The values ​​“10”, “01” and “00” are assigned to the caliber indication information CL= (C0, C1) and represent calibers CA0, CA1 and CA2 respectively, with “10” corresponding to C0= “1” and C1= “0”, “01” to C0= “0” and C1= “1” and “00” to C0= “0” and C1= “0”.

[0049] The IC calibrated current digital information is represented on 16 bits and can therefore take 2 16 =65536 different values, with IC having a minimum value Vmin = 0 and a maximum value Vmax = 65535 in this theoretical example.

[0050] Thus, for the CA0 range from 0 to 20 mA, the resulting quantization step is PQ0 = 20 mA / 65536 = 0.3 µA, for the CA1 range from 20 to 300 mA, the resulting quantization step is PQ1 = 280 mA / 65536 = 4.27 µA, and for the CA2 range from 300 to 3500 mA, the resulting quantization step is PQ2 = 3200 mA / 65536 = 48.83 µA. These quantization steps PQ0, PQ1, and PQ2, which increase with increasing natural light brightness, induce a decreasing resolution of the restored light brightness, with an applied precision of PL0 = 571 lux / 65536 = 0.0087 lux, PL0 = (8571-571) lux / 65536 = 0.12 lux, and PL2 = (10 5 -8571) lux / 65536 = 1.39 lux for calibers CA0, CA1 and CA2 respectively.

[0051] In this theoretical example, the DAC is a 16-bit linear converter. It provides the calibrated analog current control ICa corresponding to the calibrated digital current information IC. In the RN circuit, the range indication information CL selects an adjustment factor FA = F0, FA = F1 = 15F0, or FA = F2 = 175F0. These values ​​F0, F1, and F2 of the adjustment factor FA are applied to the analog control ICa for the ranges CA0 (0 to 20 mA), CA1 (20 to 300 mA), and CA2 (300 to 3500 mA), respectively. The analog current control C_ID = ICa.FA is then derived and enables the control of the current generator GC.

[0052] Thus, in general, as is clear from the theoretical example above, considering a first and a second range, for example CA0 and CA1, or CA1 and CA2, which correspond respectively to low and high values ​​of the DC current control, these cover value ranges with different extents, with the range of values ​​covered by the second range being wider than that of the first. In each of the first and second ranges, the DC current control is represented by a calibrated current digital information IC having the same fixed number of bits. This results in different qualification steps for the first and second ranges, with a quantization step for the first range that is smaller than that of the second range.The accuracy associated with the first caliber (the one for low values) is therefore greater than that associated with the second caliber (the one for high values).

[0053] With particular reference to the previous one, a practical embodiment L0 of a luminaire according to the invention is now described, having an architecture of the same type as that described above with reference to the previous ones. The luminaire L0 comprises a single light-producing channel for producing white light whose brightness can be controlled via a digital interface.

[0054] As shown schematically in the figure, the luminaire L0 comprises a group of LED diodes, labeled GD, which is powered by a DR control circuit, designated "driver" in English by those skilled in the art.

[0055] The GD group comprises a plurality of LED diodes connected in series, of the same specifications, for example white LED diodes.

[0056] The DR control circuit is powered by a switched-mode power supply unit (ALIM) connected to an AC power supply network (REac). The ALIM unit is typically integrated into the luminaire (L0) and provides a DC voltage (Vs) and one or more other voltages required to power the various components of the luminaire (L0).

[0057] The DR control circuit essentially comprises a microcontroller (MCU). L0 , a digital-to-analog converter DAC, an analog level recovery circuit RN and a voltage-controlled current generator GC.

[0058] The MCU microcontroller L0 is coupled to a Pi / o digital control interface for the luminaire L0, typically a serial interface. The MCU microcontroller L0It houses, in internal memory (MEM), embedded software responsible for the functional management of the L0 luminaire. The embedded software includes, in particular, a first software module implementing the CLC function block, which processes the CNL digital light control and provides the DC digital current control. The embedded software also includes a second software module implementing the CFC function, which processes the DC digital current control and provides the CNC digital current control. The CNC control includes the calibrated IC digital current information and the CL calibration indication information.

[0059] The DAC receives the digital information IC and outputs the calibrated analog current control ICa. The DAC here is typically a 16-bit converter, preferably of the type known to those skilled in the art as "rail-to-rail," with excellent linearity and low offset.

[0060] In this embodiment, the software module implementing the CFC function and the DAC converter collaborate to perform the functions of the CF_CNA block mentioned above with reference to the.

[0061] The analog level recovery circuit RN essentially comprises four resistors R1 to R4 in series and two electronic switches T0 and T1 in the form of two MOSFET transistors. Resistors R1 to R4 are connected in series in the order R1 to R2, R2 to R3, and R3 to R4, with connection points P1, P2, and P3 between R1 and R2, R2 and R3, and R3 and R4, respectively. Resistor R1 is at the input of the circuit and is connected to the output of the DAC to receive a voltage representative of the control signal ICa. Resistor R4 is connected to ground. Switches T0 and T1 are connected between connection point P2 and ground and between connection point P3 and ground, respectively. The voltage present at connection point P1 is the current control signal C_ID, which is supplied as input to the voltage-controlled current generator GC.

[0062] Three different voltage division ratios are provided by the RN circuit, one of which is selected by the CL gauge indication information controlling switches T0 and T1. The selected voltage division ratio determines the adjustment factor FA applied to the ICa control to obtain the C_ID control.

[0063] As can be seen in Figure 1, the invention provides for a calibration step of the luminaire and dedicated means E1, E2, and E3, to compensate for a disparity in the ohmic values ​​of the resistors R1 to R4 of the RN circuit and to obtain the required accuracy. The calibration performed allows the use of lower-class resistors, which benefits the cost optimization of a luminaire according to the invention. Thus, in accordance with this feature of the invention, the values ​​(CA0, CA1, and CA2 in this embodiment) are precisely determined at the end of the luminaire manufacturing process, during this calibration step. This calibration step is preferably performed using a software routine embedded in the MCU microcontroller. L0Under the control of this routine, a reference voltage is applied to the input of the RN circuit, and the voltage present at point P1 is accurately measured using a laboratory multimeter by an operator for each voltage division ratio. The voltage division ratio being measured is selected by the routine by appropriately controlling switches T0 and T1. The measured voltage values ​​are then entered into the MCU microcontroller. L0 The routine calculates the current ranges that correspond precisely to the measured values, defining limit values ​​for these ranges that are close to the theoretical values ​​(20 mA, 300 mA, and 3500 mA in this example). The calculated values ​​defining the ranges are provided by the routine to the CFC function.

[0064] The means E1, E2 and E3 for the implementation of this calibration step include here in particular conductive contact points for measurement sampling integrated into the electronics of the luminaire, the aforementioned laboratory multimeter, the aforementioned on-board routine, human-machine communication means and others.

[0065] The voltage-controlled current generator (GC) essentially comprises a DC-DC converter (CDC) and a voltage-controlled DC power generation circuit (SC). The CDC is powered by the DC voltage Vs supplied by the power supply unit (ALIM) and provides a highly stable DC voltage Vdc. The CDC supplies an anode of the diode group GD, one cathode of which is connected to the SC circuit. The SC circuit is a current-sink type and forces the current ID to flow through the diode group GD.

[0066] The SC circuit includes, in particular, an operational amplifier AO, a MOSFET-type transistor TR, and resistors R5 and R6. The operational amplifier AO and the transistor TR operate in linear mode. Resistors R5 and R6 provide the AO with negative feedback to track its setpoint. This circuit determines a current in the diode group GD that is approximately equal to ID = C_ID / R5.

[0067] With particular reference to [reference to] [reference to] [reference to] [reference to] [reference to] [reference to] [reference to] [reference to] [reference to] [reference to] [reference to] [reference to]. This embodiment of the luminaire of the invention is designed to reproduce the brightness and color of light.

[0068] As schematically shown in Figure 1, the luminaire L1 comprises two groups of white LEDs, labeled GD1 and GD2, which are powered by driver circuits PG1 and PG2, respectively. Group GD1 contains LEDs emitting cool white light. Group GD2 contains LEDs emitting warm white light. Thus, the luminaire L1 has two light-producing channels, CN1 and CN2, so as to produce light that is a mixture of the luminous flux provided by group GD1 and that provided by group GD2.

[0069] The PG1 and PG2 control circuits have the same architecture and each include a DAC, an RN circuit, and a GC current generator. In this L1 luminaire, these DAC, RN, and GC components are analogous to those described above with reference to the, and will not be detailed again here.

[0070] The PG1 and PG2 circuits receive CNC1 and CNC2 digital current commands as input and deliver corresponding ID1 and ID2 outputs which power the diode groups GD1 and GD2, respectively.

[0071] The CNC1 and CNC2 commands are similar to the CNC command described above and include IC1, CL1, and IC2, CL2 information, respectively. The IC1, IC2, and CL1, CL2 information are similar to the calibrated current digital information IC and the range indication information CL described above.

[0072] In this embodiment, a microcontroller MCU L1 The two light-producing channels CN1 and CN2 are controlled by a digital light command CNL0. The digital light command CNL0 is received in the luminaire L1 via an SP radio transmission module, for example of the "LoRa®" type, and is provided to the microcontroller MCU L1 via its Pi / o interface.

[0073] The CNL0 command includes brightness and color information. Digital current commands CC1 and CC2 are calculated from the aforementioned information contained in the CNL0 command. The CC1 and CC2 commands are then processed to produce the CNC1 and CNC2 commands, which are supplied to the inputs of the PG1 and PG2 circuits, respectively.

[0074] The MCU microcontroller L1Its MEM contains a software module CLC0 and software modules CFC1 and CFC2. Module CLC0 is responsible for calculating the CC1 and CC2 commands from the information contained in the CNL0 command. The CC1 and CC2 commands are then processed by modules CFC1 and CFC2, respectively. Modules CFC1 and CFC2 perform binary format reductions on the CC1 and CC2 commands to obtain the CNC1 and CNC2 commands. The binary format reductions performed are similar to those described above, with reference to [reference missing]. The CNC1 and CNC2 commands are then provided to the PG1 and PG2 circuits and processed by their various functional components, as described previously, to produce the ID1 and ID2 currents and power the GD1 and GD2 diode groups.

[0075] Although not shown in the figure, for reasons of readability, it should be noted that luminaire L1 includes the means necessary for its calibration at the end of manufacturing, as described for luminaire L0 with reference to the figure. During this calibration, the gauges used in each of the light production channels CN1 and CN2 are precisely defined.

[0076] With reference now more specifically to laet la, a particular embodiment IEI of an interior lighting system according to the invention, designed to deliver a luminous flux mimicking daylight, is described below. The IEI interior lighting system here takes the form of a daylight lighting installation in a residential building BA.

[0077] The IEI interior lighting system comprises a plurality of luminaires of the invention, L1, … Ln, L(n+1), … LN, which are distributed in one or more rooms of building BA. Luminaires L1 to LN are of the type described in reference to [reference missing] and are equipped with LoRa® radio transmission modules. Luminaires L1 to LN receive their respective digital light commands, CNL1, … CNLn, … CNLN, via a LoRa® wireless data communication network that covers the entire building BA, or even several buildings in the case of a multi-site installation, for example.

[0078] A BC control unit including an MCU microcontroller S is also intended here to monitor the operation of the IEI system. The MCU microcontroller S It houses embedded application software (not shown) that oversees the overall operation of the lighting system. The MCU microcontroller SThe microcontroller receives, via an IE communication interface and a human-machine interface (HMI), light measurement information from one or more external CE light sensors and commands from a user (UR). The microcontroller (MCU) S processes its information and commands and produces the appropriate commands CNL1 to CNLN intended for the different luminaires L1 to LN.

[0079] The external sensor CE is, for example, mounted on the roof or facade of building BA and is connected to the control unit BC via a wireless link, or wired in another installation configuration. In all cases, the external sensor CE is positioned to receive daylight. It provides light measurement data for the operation of the IEI system, and other information that may be required by the particular embodiment of the invention, such as sensor location information or other data.

[0080] The user interacts with the IEI system, for example, via a dedicated software application installed on a computer device (such as a tablet, computer, smartphone, or other device), or via a remote control. The user can thus configure the IEI interior lighting system, which may include different lighting modes, and control its overall operation.

[0081] The invention is not limited to the particular embodiments described herein by way of example. Generally, a person skilled in the art, depending on the applications of the invention, may make various modifications and variations that fall within the scope of the invention's protection.

Claims

Light-emitting diode luminaire, known as "LED", of the type having a digital interface (Pi / o) receiving a digital light control (CNL) and means for converting said digital light control (CNL) into at least one digital current control (DC), said luminaire having at least one light-producing channel (CN) controlled by said digital current control (DC), and said light-producing channel (CN) comprising a group of light-emitting diodes (GD) connected in series, digital-to-analog conversion means (CFC, CDA, RN) receiving said digital current control (DC) and producing in response a corresponding analog current control (C_ID), and means for generating direct current (GC) supplying said group of light-emitting diodes (GD) with a direct supply current (ID) the intensity of which is a function of said analog current control (C_ID),characterized in that said digital-to-analog conversion means (CFC, CDA, RN) are arranged so as to produce said analog current control (C_ID) with a quantization step that increases as the value of said digital current control (CC) increases. Luminaire according to claim 1, comprising at least two said light production channels (CN1, CN2), characterized in that said digital light control (CNL0) includes brightness and colour information, and in that said conversion means (CLC0) of said digital light control (CNL0) convert it into at least two said digital current controls (CC1, CC2) which are supplied respectively to the two said light production channels (CN1, CN2) for the control thereof. Luminaire according to claim 1 or 2, characterized in that, in said light-producing channel (CN; CN1, CN2), said digital-to-analog conversion means (CFC, CDA, RN) comprise binary format reduction means (CFC), a linear-type digital-to-analog converter (CDA) and analog level restoration means (RN), said binary format reduction means (CFC) comprising at least two ranges (CA0, CA1, CA2) jointly covering a full dynamic range of values ​​of said digital current control (DC), a first said range (CA0; CA1) and a second said range (CA1; CA2) being associated respectively with low values ​​and high values ​​of said digital current control (DC), and the range of values ​​covered by said second range (CA1; CA2) being wider than that of the first range (CA0;CA1) and, in each of said ranges (CA0, CA1, CA2), said digital current control (DC) being represented by a calibrated digital current information (IC) and a range indication information (CL), and said calibrated digital current information (IC) having a determined number of bits equal to that of said digital-to-analog converter (DAC) and less than the number of bits of said digital current control (DC).; Luminaire according to claim 3, characterized in that said binary format reduction means (CFC) comprise three sizes (CA0, CA1, CA2). Luminaire according to claim 3 or 4, characterized in that said digital-to-analog converter (DAC) is a 16-bit converter. Luminaire according to any one of claims 3 to 5, characterized in that said analog level restoration means (RN) comprise a switchable voltage divider resistive bridge (R1 to R4, T0, T1) which is controlled in switching by said range indication information (CL, C0, C1) so as to establish a voltage division ratio which corresponds to an applied range (CA0, CA1, CA2) indicated by said range indication information (CL). Luminaire according to any one of claims 1 to 6, characterized in that, in a said light production channel (CN; CN1, CN2), said direct current generation means (GC) comprise a direct-direct type voltage converter (CDC) and a voltage-controlled current generation circuit (GC). Luminaire according to claim 7, characterized in that said voltage-controlled current generation (GC) circuit is of the so-called "current well" type and comprises an operational amplifier (AO) and a transistor (TR) of the so-called "MOSFET" type. Luminaire according to claim 1 or 2, characterized in that, in said light-producing channel, said digital-to-analog conversion means comprise a logarithmic digital-to-analog converter (DAC) LOG ). An interior lighting installation, characterized in that it comprises at least one luminaire (L1 to LN) according to any one of claims 1 to 9 installed in a building (BA), a light sensor (CE) installed outside said building (BA) and exposed to daylight, wired and / or wireless (SF) information transmission links, and control means (BC, MCU). S ), said control means (BC, MCU S) being in communication, via said links, with said sensor (CE) and said at least one luminaire (L1 to LN) and controlling said at least one luminaire (L1 to LN) based on light information provided by said sensor and control information transmitted by a user (UR) to said control means (BC, MCU) S ) via a human-machine communication (HMI) means.

Images