DE102008036992A1 - System for regulating brightness in area illuminated with artificial and natural light, has light mediums provided for lighting area with artificial light and light sensor for detecting brightness - Google Patents

Abstract

The system (1) has light mediums (15,15a) provided for lighting an area (10) with artificial light, a light sensor (20) for detecting the brightness (X-r) in the area and a light regulating unit (50) for controlling the light medium. A control mode of the light regulating unit is dependent on a brightness given value (X-s,korr), the measured value of the brightness in the area and an arithmetically determined natural light-correction value. Independent claims are included for the following: (1) a light regulating unit with an electronic circuit; (2) a method for regulating the brightness in an area illuminated with artificial and natural light; and (3) a computer program with a program code for the execution of the method.

Description

The invention relates to a system for controlling the brightness in a space that can be illuminated with artificial light and daylight, with at least one light source provided for illuminating the room with artificial light, a light sensor for detecting the luminance X _R in the room and a light control unit which activates the light source. according to the preamble of claim 1.

The invention further relates to a method for controlling the brightness in a illuminable with artificial and natural light space, with at least one provided for illuminating the room with artificial light bulbs, a light sensor for detecting the luminance X _R in the room and a light control unit which drives the light source , according to the preamble of claim 10.

Furthermore, the invention relates to a computer program with program code for carrying out the method for controlling the brightness in a illuminable with artificial and natural light space with at least one provided for illuminating the room with artificial light bulbs, a light sensor for detecting the luminance X _R in space and a light control unit which activates the lighting means when the program is executed in a computer, and a computer program with program code for carrying out the method for controlling the brightness in a lightable with artificial and natural light space with at least one provided for illuminating the room with artificial light bulbs, a Light sensor for detecting the luminance X _R in the room and a light control unit, which drives the light source, stored on a machine-readable carrier.

The The invention thus relates to the field of constant light control in Interiors with adjustable bulbs, a light sensor for detecting the brightness and a light control unit. The setting The light source is also known as dimming. For such a constant light control are two methods known.

One First known method is referred to as two-point control. If the measured brightness exceeds a preset value Set point, the light source is darkened or dimmed, namely at a predetermined brightness step. If the measured brightness is below the set point, the light source will be brightened or dimmed, and also one before fixed brightness step. It can be during of the rules come to falls below the setpoint. This is but not allowed especially in workplace lighting.

One the second known method is called a "proportional dimming strategy". The manipulated variable of the bulbs is in Dependence of the difference of the currently measured brightness and a desired and predetermined setpoint calculated. It can lead to sudden brightness change of Bulbs come, which are often perceived as disturbing.

A The constant light control in indoor areas presents a special challenge with mixed light, ie with daylight and artificial light are illuminated. These are basically all rooms with a window, through the daylight, and a lamp to complement or sole lighting with artificial light. The goal of constant light control It is there, a certain preset illuminance a reference surface, such as the work surface a table to keep constant, even if the proportion of daylight at the lighting changes during the day. Dependent on from the brightness of the daylight then the brightness of the Illuminant, which generates the amount of artificial light, automatically adjusted be that the illuminance on the reference surface preferably not change.

The illuminance on the reference surface is usually detected with a lux meter. Such a measuring device determines the illuminance, which is a pure receiver size and denotes the received radiation power per unit area. The unit of illuminance is lux, where 1 lux = 1 lumen / m ² . The illuminance on the reference surface should always be the same as possible when the ratio of artificial and natural light varies. In an extreme case, on dark night without daylight, the illuminance on the reference surface is exclusively caused by artificial light. In another extreme case, the daylight is so bright that the light source is completely switched off and the desired illuminance is caused solely by daylight. In normal operation in between changes the daylight, and the light source must be tracked so that the illuminance despite changing daylight proportion still always reaches the preset value as possible.

To determine the brightness in the room with a light sensor while the luminance is measured. This captures the brightness of extended, areal light sources. It describes what people perceive as brightness. Your unit is 1 candela / m ² . The luminance measured by a light sensor in the space above the reference surface is generally not proportional to the illuminance on the reference surface, especially if the illuminance on the reference surface is due to a constantly changing ratio of artificial light and daylight.

The EP 1 610 197 A2 describes a method and a system for controlling the brightness in a room illuminated with interior light and outside light, with at least one light source provided for illuminating the room, an interior sensor for detecting the brightness present in the room, and a control unit which controls the light source, and additionally with an outdoor sensor for detecting the outside light, wherein the control behavior of the control / regulation device is dependent on the measurement signal of the outdoor sensor. The additionally required outdoor sensor makes such a system expensive.

It is the object of the invention, a generic System and method for controlling the brightness in a room too improve, and it also with respect to the electrical and mechanical structure.

The Task is solved with respect to the system a generic system with the characteristic Features of claim 1. Regarding the method becomes the problem solved by a generic Method with the characterizing features of claim 10.

_According to the invention, the control _{behavior of} the light control unit is dependent on a luminance _target value X _S.Korr , the measured value X _{R of} the luminance in the room and a mathematically determined daylight correction value. This eliminates the need for a further light sensor for detecting the brightness of the outside light. A major advantage of the invention is that the manipulated daylight correction of the control value for the lighting means can be adjusted taking into account the changing ratio of indoor and outdoor light, and of artificial and daylight so that perceptible jumps in brightness are avoided.

According to an advantageous embodiment of the invention, the luminance _{target value} X _{S, Korr is} dependent on a first adjustment value X _S or X _SA determined under artificial light, and on the computationally determined daylight correction value.

According to a further advantageous embodiment of the invention, the daylight correction _value in the light control unit is calculated by taking into account a second adjustment _value X _TKal determined in pure daylight and the luminous _{flux characteristic} f (d _A ), which _{adjusts the} luminance measured at the light _sensor to the control value d _A Activation of the light source linked, determined.

According to a further advantageous embodiment of the invention, the light control unit determines the luminance _target value X _{S, Korr} , and the difference between the measured value X _{R of} the luminance in the room and the luminance _target value X _{S, Korr} in the light control unit is used to determine a control value d _A for controlling the lighting means used.

According to a further advantageous embodiment of the invention, the first calibration value X _{S of} the luminance is deposited after adjustment of the luminous means to a desired illuminance E _S on a reference surface in the room when illuminated with pure artificial light in the light control unit.

According to a further advantageous embodiment of the invention, the first calibration value X _{SA of} the luminance after adjustment of the luminous means to a target illuminance E _S on a reference surface in space in prevailing artificial lighting with a residual amount of daylight, which corresponds to a residual luminance X _rest , in the light control unit deposited.

According to a further advantageous embodiment of the invention, the second adjustment _value X _TKal after adjustment of the luminous means to a target illuminance E _S on a reference surface in space when illuminated alone with daylight deposited in the light control unit.

According to a further advantageous embodiment of the invention, the illuminant characteristic f (d _A ) is automatically determined in artificial lighting by successively setting a predetermined number of control values d _{A, i} for controlling the light source and stored in the light control unit.

According to a further advantageous embodiment of the invention, from the luminous flux characteristic f (d _A ), the residual luminous intensity X _residual corresponding to a residual amount of daylight prevails, stored in the light control unit and used to determine the daylight correction value.

In other words, in an advantageous variant of the system according to the invention, the light control unit determines a luminance _target value X _{S, Korr} and the difference between the measured value X _{R of} the luminance in the room and the luminance _target value in the light control unit is used to determine a control value d _A for controlling the luminous means wherein the luminance _{target value} X _{S, Korr is determined by} taking into account a first adjustment value X _S or X _SA determined under artificial light, and a daylight-dependent correction value, and wherein the daylight-dependent correction value in the light control unit is calculated using a second, determined in pure daylight Adjustment _value X _TKal , and the luminous _{flux characteristic} f (d _A ), which combines the luminance measured at the light _sensor with the control value d _A for controlling the light source, is determined in such a way that perceptible brightness jumps are avoided in the room.

An inventive method is characterized in that the light source is controlled by the light control unit in response to a luminance target X _{S, Korr} , the measured value X _{R of} the luminance in the room and a mathematically determined daylight correction value.

In an advantageous embodiment of the method _according to the invention, the luminance _{target value} X _{S, Korr is determined} as a function of a first adjustment value X _S or X _SA determined under artificial light, and the calculated daylight correction value.

In an advantageous embodiment of the method _according to the invention, the daylight correction _value in the light control unit is calculated using a second adjustment _value X _TKal , determined in pure daylight, and the luminous _{flux characteristic} f (d _A ), which _{adjusts the} luminance measured at the light _sensor to the control value d _A Activation of the light source linked, determined. In an advantageous embodiment of the method _according to the invention, the luminance _target value X _{S, Korr} in the light control unit is determined and the difference between the measured value X _{R of} the luminance in the room and the luminance _target value X _{S, Korr} in the light control unit for determining a control value d _A for controlling the light source used. In an advantageous embodiment of the method according to the invention, a target illuminance E _{S is set} on a reference surface in the room when illuminated with pure artificial light by appropriate adjustment of the illuminant, and the case measured with the probe luminance is the first adjustment value X _{S of} the luminance in the light control unit deposited.

In an advantageous embodiment of the method according to the invention, a target illuminance E _{S is set} on a reference surface in the room with prevailing artificial lighting with a residual amount of daylight which corresponds to a residual luminance X _rest , and the luminance measured with the sensor becomes the first adjustment value X _{SA of} the luminance deposited in the light control unit.

In an advantageous embodiment of the method according to the invention, a target illuminance E _{S is set} on a reference surface in the room when illuminated alone with daylight and the case measured with the probe luminance is stored as the second adjustment _value X _TKal in the light control unit.

In an advantageous embodiment of the method according to the invention, the luminous flux characteristic f (d _A ) is automatically determined in artificial lighting by successively setting a predetermined number of control values d _{A, i} for controlling the lamp and stored in the light control unit.

In an advantageous embodiment of the method according to the invention is from the luminous flux characteristic f (d _A ) the residual amount of _residual light intensity _{residual rest} X _rest determined with a residual amount of daylight with otherwise prevailing artificial light, deposited in the light control unit and used to determine the daylight correction value.

• – Ermitteln eines ersten Abgleichwertes X_S bzw. X_SA der Leuchtdichte bei Kalibrierung auf eine Soll-Beleuchtungsstärke E_S auf einer Bezugsfläche im Raum bei Be leuchtung mit Kunstlicht;
• – Ermitteln eines zweiten Abgleichwertes X_TKal der Leuchtdichte bei Kalibrierung auf eine Soll-Beleuchtungsstärke E_S auf der Bezugsfläche bei Beleuchtung mit Tageslicht;
• – Ermitteln eines Sollwertes X_S,Korr aus den beiden Abgleichwerten X_S, X_T sowie der gemessenen Leuchtdichte X_R;
• – Ermitteln eines Stellwertes d_A zur Ansteuerung der Lichtquelle unter Verwendung der Differenz des Korrekturwertes und der gemessenen Leuchtdichte;

so dass aufgrund des Einbezugs der beiden Kalibrierwerte X_T, X_S wahrnehmbare Helligkeitssprünge vermieden werden.In other words, an advantageous embodiment of a method according to the invention is characterized by the following method steps:

• - Determining a first adjustment value X _S or X _{SA of} the luminance when calibrated to a target illuminance E _S on a reference surface in space at Be lighting with artificial light;
• - Determining a second adjustment _value X _TKal the luminance when calibrated to a target illuminance E _S on the reference surface when illuminated with daylight;
• - determining a desired value X _{S, Corr} from the two adjustment values X _S, X _T and the measured luminance X _R;
• - Determining a control value d _A for controlling the light source using the difference of the correction value and the measured luminance;

so that perceptible brightness jumps are avoided due to the inclusion of the two calibration values X _T , X _S.

Further Advantages of the invention and further advantageous embodiments The invention can be found in the further claims.

Based of the drawings, in which two embodiments of the Invention are shown, the invention and further advantageous Embodiments and improvements of the invention in more detail shown and described.

It demonstrate

1 A first embodiment of a system according to the invention,

2 a first embodiment of a method according to the invention,

3 a second embodiment of a system according to the invention, and

4 a second embodiment of a method according to the invention.

It will be the first 1 considered. This shows a system 1 for controlling the brightness in a room 10 ,

The space 10 has a window 12 through which outside light, also called daylight, can enter the room. On the ground 13 of the room 10 there is a table whose table top is a reference surface 14 forms. The table with the reference surface 14 should be representative of all possible furnishings of the room, which should be illuminated with a sufficient and be determined by the user of the room brightness. For example, the table may be a workbench, another assembly workstation or an office desk. As a measure of the brightness, the illuminance used is that of a lux meter 30 on the reference surface 14 is determined.

On the ceiling 11 of the room 10 There are two light sources for lighting the room 10 with artificial light 15 . 15a , also known as bulbs. The two bulbs 15 . 15a can also be part of a single lamp and controlled together.

Between the two bulbs 15 . 15a is on the ceiling 11 another light sensor 20 , This measures the luminance in the room. He is attached so that he is above the reference surface as possible 14 is located so that it has the luminance near this reference surface 14 determined.

The system 1 further comprises a light control unit 50 , The light control unit 50 may be an electronic circuit with a microprocessor. The in the light control unit 50 as subunits with covered parts, here a regulator 51 , a cold junction 53 and a setpoint correction unit 52 may also be electronic assemblies, or they may be program modules of a microprocessor program, also called computer program, which is the method within the light control unit 50 performs and monitors. The computer program can then be, for example, in the form of firmware part of the microprocessor system, or it can be played on a disk, a CD or a memory stick, for example, in the microprocessor system.

The light control unit 50 takes the measured values X _{R of} the luminance from the light sensor 20 up and processing them. The light control unit 50 calculated from the measured values ultimately the manipulated variable d _A for the bulbs 15 . 15a , In the example shown, both bulbs 15 . 15a from a single light control unit 50 controlled, they both get the same control value d _A. Of course, each light source could also be assigned its own light control unit and receive a separate control value d _A from the light control unit assigned to it.

The light control unit 50 has the task, in interaction with the bulbs 15 . 15a keep the brightness on the reference surface under the light sensor as constant as possible.

The desired brightness is set during a so-called night adjustment, which is a calibration carried out under artificial lighting. For this purpose, the manipulated variable d _A for the bulbs 15 . 15a changed so long until the lux meter 30 on the reference surface 14 shows the desired value. This value of the target illuminance is referred to as E _s . The ler at this target illuminance E _S of the Lichtfüh 20 Measured value of the luminance is referred to as the first adjustment value X _S.

The light control unit 50 is now calibrated to the desired illuminance E _S. This illuminance E _S is to be kept as constant as possible during the course of the day. Under no circumstances should the desired illuminance E _{S be} undershot.

A special feature of the scheme is that during the determination of the target illuminance E _S, the illuminance of the reference surface 14 with a luxmeter 30 is detected. The light sensor 20 However, it measures the luminance, ie another physical unit. The generation of the control value d _A for the bulbs 15 . 15a in the light control unit 50 Thus, based on a measurement of a different physical quantity than that of the determination of the target illuminance E _S on the reference surface 14 underlying.

at a constant relationship between artificial and natural light the luminance of the illuminance would be proportional. A simple two-point control would be at a constant Relationship between artificial and natural light work.

During a day, however, the relationship between artificial light and daylight changes almost every minute. In order nevertheless to be able to maintain the desired target illuminance ES on the reference surface, the control behavior of the light control unit is 50 from a luminance _target value X _{S, Korr} , the measured value X _{R of} the luminance in the room and a mathematically determined daylight correction value. The light control unit 50 includes a regulator 51 , This generates as output the control value d _A for the bulbs 15 . 15a , The bulbs 15 . 15a can be dimmable lamps, the control value d _A is then the control value for the dimmer.

The deviation 54 that the regulator 51 is fed, calculated at a reference junction 53 as the difference from the measured value X _{R of} the luminance, as measured by the light sensor 20 is determined, and the luminance setpoint X _{S, Korr} . The luminance target value X _{S, Korr} is in a setpoint correction unit 52 , which also part of the light control unit 50 is calculated.

The determination of the luminance setpoint value X _{S, Korr} takes place in the setpoint correction unit 52 taking into account that of the light sensor 20 determined measured value X _{R of} the luminance, the current control value d _A for the bulbs 15 . 15a , the first adjustment value X _S , the luminance characteristic f (d _A ), which describes the luminance component generated by the luminous means as a function of the control _value d _A , and a second calibration _value X _{TKal of} the luminance determined in pure daylight.

The method used here calculates from the measured luminance X _R and the brightness set via the control value d _A at the light sources 15 . 15a the proportion of daylight.

• 1. Ermittlung des Sollwertes X_S,Korr Es wird dabei bestimmt, wie hoch der Sollwert X_S,Korr bei einem errechneten Verhältnis zwischen Kunst- und Tageslicht sein müsste.
• 2. Anpassung der Helligkeit an den Leuchtmittel: Ist der vom Lichtfühler gemessene Wert X_R der Leuchtdichte höher als der ermittelte Sollwert X_S,Korr, wird der Stellwert d_A um einen Schritt verringert, umgangssprachlich sagt man, es wird um einen Schritt runter gedimmt. Dabei wird davon ausgegangen, dass die Dimmung des Leuchtmittels 15, 15a in diskreten Schritten mit einer von dem jeweiligen Leuchtmittel bzw. dessen Stelleinrichtung vorgegebenen Schrittweite erfolgt. Ist der vom Lichtfühler gemessene Wert X_R der Leuchtdichte dagegen niedriger als der ermittelte Sollwert X_S,Korr wird der Stellwert d_A um einen Schritt vergrößert, umgangssprachlich sagt man, es wird um einen Schritt raufgedimmt. Sind der vom Lichtfühler gemessene Wert X_R der Leuchtdichte und der ermittelte Sollwert X_S,Korr gleich, wird nicht gedimmt.
• 3. Wartezeit bis zur nächsten Messung Abhängig vom Unterschied zwischen dem ermittelten Sollwert X_S,Korr und dem der vom Lichtfühler gemessenen Wert X_R der Leuchtdichte wird eine Wartezeit bis zur nächsten Messung eingehalten.

For this the following steps are carried out:

• 1. Determination of the setpoint X _{S, Korr} It is thereby determined how high the setpoint X _{S, Korr would have to be} for a calculated ratio between artificial and daylight.
• 2. Adjustment of the brightness to the light source: If the value X _{R of} the light density measured by the light sensor is higher than the determined target value X _{S, Korr} , the control value d _A is reduced by one step, colloquially it is said to be dimmed one step down , It is assumed that the dimming of the bulb 15 . 15a takes place in discrete steps with a predetermined by the respective lighting means or its actuator step size. On the other hand, if the value X _{R of} the luminance measured by the light _sensor is lower than the determined desired value X _{S, Korr} , the manipulated variable d _{A is} increased by one step, colloquially it is said to be stepped up by one step. If the value X _{R of} the luminance measured by the light sensor and the determined desired value X _{S, Korr are} equal, no dimming takes place.
• 3. Waiting time until the next measurement Depending on the difference between the determined setpoint X _{S, Korr} and the value X _{R of} the luminance measured by the light sensor, a waiting time until the next measurement is observed.

A "proportional dimming strategy" known in the prior art does not calculate the setpoint value X _{S, Korr} , but instead the control value d _A for the lighting means is recalculated again and again. It can happen that it comes to visible jumps in brightness at the bulbs. This is often perceived as disturbing.

Here in the light control unit 50 This can not occur using the method according to the invention.

The algorithm used here corrects the setpoint value X _{S, Korr} that has to be newly set as a function of the current control value d _A , the current measured value X _{R of} the luminance and the current setpoint.

With a artificial light adjustment to the illuminance E _S , a first adjustment value X _{S is} determined.

The light sensor measures the luminance X _R in the room. This is composed of a daylight component X _T and an artificial light component X _K : X R = X T + X K (1)

The proportion of artificial light X _K is not proportional to the current control value d _A. The relationship between the control value d _A and the resulting proportion of artificial light X _{K of} the luminance is different from light source to light source.

Therefore, the characteristic f (δ _A ) of the lamp must be determined for each lamp. X K = f (δ A ) (2)

Thus, the daylight component X _{T of} the luminance is calculated as follows: X T = X R - f (δ A ) (3)

The determination of the setpoint X _{S, Korr} depends on the _proportion of daylight. The setpoint value X _SKor is composed of the first adjustment value X _S and a daylight correction value X _d . X Skor = X S + X δ (4)

Experiments have shown that the increase of the correction value X _d in a first approximation is proportional to the daylight component X _T.

So: X δ = f x · X T (5)

With a day adjustment to the target illuminance E _S luminance X _{TKal is determined} in pure daylight.

At this reference point, the value X _{TKal corresponds to} the setpoint X _SKor . Thus, it can be estimated how much the setpoint increases at a reference point. Here can be seen proportional conditions. X δKal = f x · X Tkal (6) Or X Tkal - X S = f x · X Tkal (7)

It follows for the compensation factor f _x

X_TKal:

die gemessene Leuchtdichte beim Tageslichtabgleich auf E_S

Where:

X _TKal :

the measured luminance in the daylight adjustment on E _S

So the corrected setpoint results as follows:

The determination of X _S is usually done with a artificial light balance and should be done without any daylight. Unfortunately, this is not always possible. In some cases you have a balance of artificial light balance due to daylight X _rest , such as when the artificial light adjustment is performed during the day and darkened window, but through the window darkening still a bit of daylight penetrates into the room. The daylight residual of the luminance can be determined when recording the luminous characteristic, as will be described below.

In this case, the first adjustment value is called X _SA , and it holds X S = X SA - f x · X rest (8th)

Inserted in (7): X Tkal - (X SA - f x · X R ) = f x · X Tkal

It follows for the compensation factor f _x

X_Tkal:

die gemessene Leuchtdichte beim Tageslichtabgleich auf E_S

Here is also:

X _Tkal :

the measured luminance in the daylight adjustment on E _S

In this case, therefore, the corrected setpoint with the value X _SA determined during the artificial light adjustment results as follows:

The 3 shows the variant of the system according to the invention for the case that a remainder of luminance due to daylight X _rest during artificial light balance is present. The only difference to the system according to 1 is that the remainder of luminance due to daylight X _rest as another factor in the determination of the setpoint X _{S, Korr} in the setpoint correction unit 52 received.

In order to determine the luminous flux characteristic curve, a number of different brightnesses are successively set; in one example, which is not limiting for the invention, however, max. 32 different brightnesses are set, and the resulting measured value X _{R of} the luminance is determined and stored together with the associated control value d _A. This relationship is the luminous flux characteristic f (d _A ), which is then used as a basis for the further control.

In a particular embodiment of the method for determining the luminous flux characteristic to be mentioned here but not as limiting to the present Invention is to be considered, in other words, you can too do differently after a new brightness value is set was waited a certain amount of time as the "minimum Time between 2 control steps "is set. In an example Such a minimum waiting time can be 1 s. Then the Sensor value evaluated cyclically. If doing 3 times in a row the same sensor value is read in, this will be valid Value entered in the characteristic curve.

The Brightness values are traveled from maximum brightness to 0.

If always the same sensor values for 3 brightness levels in a row determined, the determination of the characteristic is terminated. The remaining values are filled with the last read value.

As a last step, the light source is switched off (brightness 0). Here the rest daylight X _{rest is} determined.

The 2 gives a summary of the inventive method for controlling the brightness in the form of a flow chart. When commissioning the system, the illuminant characteristic f (d _A ) is determined as preparatory steps, an adjustment carried out solely with artificial light to determine the first adjustment value X _S , a further adjustment carried out alone with daylight to determine the second adjustment _value X _TKal . The luminous means characteristic and the two adjustment values are stored in the setpoint correction unit, for example stored in a memory, and are then available to the computer program for carrying out the method.

Subsequently, a first control value for the light source is set. After the minimum waiting time, the measured value X _{R of} the luminance is determined with the light sensor. In the setpoint correcting unit, the setpoint value X _{S, Korr is} calculated as described above and compared with the measured value X _R.

in the Case of coincidence of measured value and setpoint becomes again the minimum waiting time waited, and then again the measured value determines the setpoint calculated and compared.

The control value d _A, when a deviation is detected, is increased or reduced by a sub-step .DELTA.d _A, depending on whether the measured value is output is less than or greater than the target value, and as a new control value to the bulbs. Once the minimum waiting time has been waited, the measured value is again determined, the setpoint calculated, the measured and setpoint value compared, etc.

The process scheme according to 4 differs from the process scheme 2 The fact that the artificial light balance is not carried out with pure artificial light, but predominantly with artificial light with a residual amount X _remainder of daylight, so that when determining the target value X _{S, Korr} in the setpoint correction unit 52 this residual proportion X _residual in daylight is still taken into account.

In addition, it should be mentioned that it is helpful when performing the artificial light and the daylight balance of the room 10 already furnished as it will later be in normal operation. Because then influences of furnishings on the determination of the measured value of the luminance X _{R are} already detected during the comparison with.

The Quality of the scheme can be further increased, if care is taken that the light sensor during the operation is not exposed to direct sunlight.

The according to the invention and described above To control the brightness can also be used as part of the operating and programming software a building installation bus, such as the KNX / EIB bus, be used. The computer program to carry out of the method can then, for example, also centrally on the control computer of the building bus lie and work.

1

system

10

room

11

blanket

12

window

13

ground

14

Table, reference surface

15 15a

Light source Lamp

16

interior light

17

exterior light

20

light sensor

30

Luxmeters

50

Light control unit

51

regulator

52

Setpoint correction unit

53

junction

54

deviation

It

Target illuminance

d _A

control value

X _R

reading the luminance

X _S

first Adjustment value (with pure artificial light)

X _{S, corr}

Luminance setpoint

f (d _A )

Lamp characteristics

X _Tkal

second balance value

X _SA

first Adjustment value for adjustment mainly with artificial light

X _rest

rest on luminance due to daylight during adjustment predominantly with artificial light

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1610197 A2 [0010]

Claims (26)

A system for controlling the brightness in a room that can be illuminated with artificial light and daylight, with at least one light source provided for illuminating the room with artificial light, a light sensor for detecting the luminance X _R in the room and a light control unit which activates the light source, characterized in that the control behavior of the light control unit of a luminance _target value X _{S, Korr} , the measured value X _{R of} the luminance in the room and a mathematically determined daylight correction value is dependent. The system according to claim 1, wherein the luminance _{target value} X _{S, Korr} is dependent on a first adjustment value X _S or X _SA determined under artificial light, and on the computationally determined daylight correction value. System according to claim 2, wherein the daylight correction _value in the light control unit calculates a second calibration _value X _TKal determined in pure daylight and the luminous _{flux characteristic} f (d _A ), which _{measures the} luminance measured at the light _sensor with the control value d _A for controlling the Illuminant is linked, determined. System according to claim 3, wherein the light control unit determines the luminance _target value X _{S, Korr} and the difference between the measured value X _{R of} the luminance in space and the luminance _target value X _{S, Korr} in the light control unit is used to determine a control value d _A for controlling the luminous means. System according to claim 4, wherein the first adjustment value X _{S of} the luminance is deposited after adjustment of the luminous means to a target illuminance E _S on a reference surface in space when illuminated with pure artificial light in the light control unit. System according to claim 4, wherein the first calibration value X _{SA of} the luminance after adjustment of the luminous means to a target illuminance E _S on a reference surface in space in prevailing artificial lighting with a residual amount of daylight, which corresponds to a residual luminance X _rest , is stored in the light control unit , System according to claim 5 or 6, wherein the second adjustment _value X _TKal after adjustment of the luminous means to a target illuminance E _S on a reference surface in the room when illuminated alone with daylight is stored in the light control unit. System according to claim 7, wherein the luminous flux characteristic f (d _A ) is automatically determined in artificial lighting by successively setting a predeterminable number of control values d _{A, i} for controlling the lighting means and stored in the light control unit. System according to claim 8, wherein from the luminous flux characteristic f (d _A ) determines the residual luminous intensity X _rest corresponding to a residual amount of daylight with otherwise prevailing artificial lighting, deposited in the light control unit and used to determine the daylight correction value. Light control unit ( 50 ) for use in a system according to claim 1, comprising an electronic circuit with a microprocessor. Light control unit ( 50 ) according to claim 10, which as subunits a regulator ( 51 ), a cold junction ( 53 ) and a setpoint correction unit ( 52 ), wherein the subunits ( 51 . 53 . 52 ) are electronic assemblies. Light control unit ( 50 ) according to claim 10, which as subunits a regulator ( 51 ), a cold junction ( 53 ) and a setpoint correction unit ( 52 ), wherein the subunits ( 51 . 53 . 52 ) Are program modules of a microprocessor program. Light control unit ( 50 ) according to claim 12, wherein the microprocessor program as firmware is part of the microprocessor. Method for controlling the brightness in a room that can be illuminated with artificial light and daylight, with at least one illuminant provided for illuminating the room, a light sensor for detecting the luminance X _R in the room and a light control unit which activates the illuminant, characterized in that the illuminant from the light control unit in response to a luminance target value X _{S, Korr} , the measured value X _{R of} the luminance in the room and a mathematically determined daylight correction value is controlled. A method according to claim 14, wherein the luminance _{target value} X _{S, Korr is determined} as a function of a first adjustment value X _S or X _SA determined under artificial light, and the calculated daylight correction value. The method of claim 15, wherein the daylight correction _value in the light control unit mathematically with reference to a second, determined in pure daylight adjustment X _TKal , and the luminous _{flux characteristic} f (d _A ), which _{measures the} luminance measured at the light _sensor with the control value d _A for controlling the Illuminant is linked, determined. The method of claim 16, wherein the luminance _target value X _{S, Korr is determined} in the light control unit and the difference between the measured value X _{R of} the luminance in the room and the luminance target value X _{S, K} in the light control unit for determining a control value d _{A used} to control the light source becomes. The method of claim 17, wherein a target illuminance E _{S is set} on a reference surface in space under illumination with pure artificial light by appropriate adjustment of the light source, and thereby measured with the probe luminance is deposited as the first adjustment value X _{S of} the luminance in the light control unit , A method according to claim 17, wherein a target illuminance E _{S is set} on a reference surface in the room at prevailing artificial lighting with a residual amount of daylight corresponding to a residual luminance X _rest , and the luminance measured thereby with the sensor as the first adjustment value X _SA Luminance is deposited in the light control unit. The method of claim 18 or 19, wherein a target illuminance Es is set on a reference surface in the room when illuminated alone with daylight and thereby measured with the probe luminance is deposited as a second adjustment _value X _TKal in the light control unit. A method according to claim 20, wherein the luminous flux characteristic f (d _A ) is automatically determined in the case of artificial lighting by successively setting a predefinable number of control values d _{A, i} for driving the luminous means and deposited in the light control unit. The method of claim 21, wherein from the luminous flux characteristic f (d _A ) which determines a residual amount of daylight with otherwise prevailing artificial lighting corresponding residual luminosity X _rest , deposited in the light control unit and used to determine the daylight correction value. Computer program with program code for execution The method of any one of claims 14 to 22 when the program is running in a computer. Computer program according to claim 23, which is based on Control computer running a building installation bus becomes. Computer program according to claim 23, which is in the microprocessor of the light control unit ( 50 ) is performed. Computer program according to claim 23, stored on a machine readable carrier.