JP4779215B2

JP4779215B2 - Lighting control device

Info

Publication number: JP4779215B2
Application number: JP2001054696A
Authority: JP
Inventors: 康司森本; 和穂田中; 寿明高橋
Original assignee: Toshiba Lighting and Technology Corp
Current assignee: Toshiba Lighting and Technology Corp
Priority date: 2001-02-28
Filing date: 2001-02-28
Publication date: 2011-09-28
Anticipated expiration: 2021-02-28
Also published as: JP2002260880A

Description

【０００１】
【発明の属する技術分野】
本発明は、照度センサを使用して床面の照度値を測定し、予め記憶した目標照度値になるように照明器具の光束を調整し、床面の照度を一定に保持するよう制御するように構成した照明制御装置において、調光度の下限における調光制御時に際し、照明器具を調光度の下限で動作させている時の照度値が、照明器具を消灯しても目標照度値を越えるような外光があることを判定して、消灯制御を行うように構成した照明制御装置に関するものである。
【０００２】
【従来の技術】
従来において、床面の照度を照度センサを使用して床面からの反射光により検出し、この照度センサによる検出値に基づいて照明器具に対し照度一定制御を行うように構成した照明制御装置は公知である。図５は、照明制御装置の設定状態の構成例を示す説明図であり、床面１０に対し、所定距離離間した上方に、前記床面１０とほぼ平行な天井１２が設けられている。また天井１２には、蛍光ランプ等からなる照明器具１４およびこの照明器具１４の照射領域の明るさを検出する照度センサ１６が配設されている。そして、前記照度センサ１６には照明制御装置２０が接続配置されると共に、この照明制御装置２０に照明器具１４が接続されている。
【０００３】
しかるに、一般に、照度センサ１６で検出される天井１２の近傍における明るさすなわち照度値Ｌは、照明器具１４以外からの光束が無い場合には、照明器具１４から発する光束Φが床面１０に到達し、この床面１０から反射係数κで反射した光束が天井１２に到達した単位面積当りの光束で求められる。
【０００４】
従って、天井１２に照度センサ１６を配置した場合、測定しようとする床面１０の明るさすなわち照度値Ｌは、反射係数κによって変化する。このため、照度センサ１６とは別個の照度計を使用して床面１０の照度値を検出し、前記照度計と照度センサ１６との照度値の相違から床面１０の反射係数κを算出し、この反射係数κを用いて照明器具１４の照度すなわち明るさを設定することができる。
【０００５】
しかるに、実際に建物等の室内に配置されている照明器具において、照明制御装置により調光制御を行う場合には、照度センサにより床面の照度値を測定するに際しては、照明器具の明るさに外光の明るさが加わることになる。また、調光可能な照明器具を使用する場合、図６に示すように、調光装置による調光可能な制御範囲は、消灯〜全光（１００％点灯）ではなく、一定の下限値を有している場合が多い。特に、蛍光ランプをインバータ駆動する場合、調光可能な制御範囲の下限値は、全光に対し２５％〜５０％程度であることが多い。
【０００６】
なお、一般に、照度は面積当りの光束の量に比例することから、図６に示す照明器具の典型的な調光制御特性において、調光可能な制御範囲の照度値は、照明器具からの光束と、それ以外（殆んどが外光）の光束との和に比例する。従って、照明器具の調光可能な制御範囲（下限から全光までの間）においては、照度値は調光度に比例する。そして、調光可能な制御範囲の下限以下においては、消灯に移行するので、外光のみによる照度値となる。この場合、前記調光可能な制御範囲の下限での照度値Ｌm は、外光の明るさ（照度値Ｌa ）と、調光可能な制御範囲の下限で点灯した時の照明器具のみによる明るさ（照度値Ｌ0 ）との和（Ｌm ＝Ｌa ＋Ｌ0 ）で表される。
【０００７】
【発明が解決しようとする課題】
このような調光制御特性を有する従来の照明制御装置において、目標照度値Ｌp と調光動作によるそれぞれ外光による照度値Ｌa が変化する場合の照度値（Ｌ1 、Ｌ2 、Ｌ3 ）との関係を示せば、図１に示す通りである。
【０００８】
すなわち、図１において、まず目標照度値Ｌp が設定される。そこで、実線で示すような調光制御特性ａの場合においては、調光度の下限における照度値Ｌm とその時の外光の照度値Ｌa との関係は、Ｌm −Ｌ0 ＝Ｌa である。この場合、前記照度値Ｌ0 は、前述したように調光度の下限で点灯した時の照明器具のみによる床面照度値Ｌ0 であり、照明器具固有の特性値である。そして、この調光制御特性ａでは、前記外光の照度値Ｌa は、前記目標照度値Ｌp を下回ることになるので、照明器具を消灯することは好ましくない。次に、破線で示すような調光制御特性ｂの場合においては、調光度の下限における照度値Ｌm ′とその時の外光の照度値Ｌa ′との関係は、Ｌm ′−Ｌ0 ′＝Ｌa ′である。そして、この調光制御特性ｂでは、前記外光の照度値Ｌa ′は、前記目標照度値Ｌp をさらに下回ることになるので、照明器具を消灯することは好ましくない。さらに、点線で示すような調光制御特性ｃの場合においては、調光度の下限における照度値Ｌm ″とその時の外光の照度値Ｌa ″との関係は、Ｌm ″−Ｌ0 ″＝Ｌa ″である。そして、この調光制御特性ｃでは、前記外光の照度値Ｌa ″は、前記目標照度値Ｌp を上回ることになるので、照明器具を消灯することが好ましい。
【０００９】
そこで、本発明者等は、種々検討を重ねた結果、前述した調光制御特性ｃの場合のように、照明器具を調光度の下限で動作させている時点の外光を含む照度値（Ｌm ）から、目標照度値（Ｌp ）を減じた値が、調光度の下限で点灯した時の照明器具のみによる床面照度値（Ｌ0 ）と、等しいかあるいは大きい場合（Ｌm −Ｌp ≧Ｌ0 ）には、照明器具を消灯制御するように構成すれば有効であることを突き止めた。
【００１０】
また、この場合、前記調光度の下限で点灯した際の照明器具のみによる床面照度値（Ｌ0 ）については、制御対象となる照明器具についての調光制御特性において、少なくとも任意の２点の調光度（Ｄ1 →Ｄ2 ）により点灯した場合の照度値（Ｌ1 →Ｌ2 ）から、その変化率（勾配）［Ｌ0 ＝（Ｌ2 −Ｌ1 ／Ｄ2 −Ｄ1 ）］を求めると共に、この変化率（勾配）に基づいて調光度の下限で照明器具を点灯した時の照度値を算出することにより、簡便に求めることができる。
【００１１】
従って、本発明の目的は、照度センサを使用して床面の照度値を測定し、予め記憶した目標照度値になるように照明器具の光束を調整し、床面の照度を一定に保持するよう制御するように構成した照明制御装置において、調光度の下限における調光制御時に際して、その時の外光の照度値が目標照度値を上回る場合には、照明器具を消灯制御して、省エネルギー効果を簡便かつ有効に発揮させることができる照明制御装置を提供することにある。
【００１２】
【課題を解決するための手段】
前記目的を達成するため、本発明に係る照明制御装置は、照度センサを使用して床面の照度値を測定し、予め記憶した目標照度値になるように照明器具の光束を調整し、床面の照度を一定に保持するよう制御するように構成した照明制御装置において、少なくとも任意の２点の調光度により点灯した場合の照度値から、調光度の下限で点灯したときの照明器具のみによる床面照度Ｌ0を算出し、照明器具を調光度の下限で動作させている際に、その時点の外光を含む照度値Ｌmから、目標照度値Ｌpを減じた値が、調光度の下限で点灯した時の照明器具のみによる床面照度値Ｌ0と、等しいかあるいは大きい場合（Ｌm−Ｌp≧Ｌ0）には、照明器具を消灯制御し、照明器具を消灯制御している際に外光の照度値Ｌaが目標照度値Ｌpを下回ると照明器具を点灯制御することを特徴とする。
【００１３】
また、前記照明器具を調光度の下限で動作させている際に、その時点の外光を含む照度値Ｌm と、調光度の下限で点灯した時の照明器具のみによる床面照度値Ｌ0 とから求められる外光の照度値Ｌa （＝Ｌm −Ｌ0 ）が、目標照度値Ｌp と等しいかあるいは大きい場合（Ｌa ≧Ｌp ）には、照明器具を消灯制御するように構成することもできる。
【００１５】
この場合、前記少なくとも任意の２点の調光度のうち１点の調光度は、照明器具の調光度の下限（消灯動作点）に設定することができる。
【００１８】
【発明の実施の形態】
次に、本発明に係る照明制御装置の実施例につき、添付図面を参照しながら、以下詳細に説明する。
【００１９】
本発明に係る照明制御装置は、前述した図１に示すように、まず目標照度値Ｌp を設定し、点線で示すような調光制御特性ｃの場合において、調光度の下限における照度値Ｌm ″とその時の外光の照度値Ｌa ″との関係が、Ｌm ″−Ｌ0 ″＝Ｌa ″であれば、この調光制御特性ｃでは、前記外光の照度値Ｌa ″は、前記目標照度値Ｌp を上回ることになるので、照明器具を消灯制御するように構成することを特徴とするものである。
【００２０】
一方、本発明に係る照明制御装置では、図１において、例えば実線で示すような調光制御特性ａの場合、調光度の下限における照度値Ｌm とその時の外光の照度値Ｌa との関係は、Ｌm −Ｌ0 ＝Ｌa である。この場合、前記照度値Ｌ0 は、前述したように調光度の下限で点灯した時の照明器具のみによる床面照度値Ｌ0 であり、照明器具固有の特性値である。そして、この調光制御特性ａでは、前記外光の照度値Ｌa は、前記目標照度値Ｌp を下回ることになるので、照明器具は消灯制御しない。また、破線で示すような調光制御特性ｂの場合、調光度の下限における照度値Ｌm ′とその時の外光の照度値Ｌa ′との関係は、Ｌm ′−Ｌ0 ′＝Ｌa ′である。そして、この調光制御特性ｂでは、前記外光の照度値Ｌa ′は、前記目標照度値Ｌp をさらに下回ることになるので、前記と同様に照明器具は消灯制御しない。
【００２１】
そこで、前述した本発明に係る照明制御装置の制御動作プログラムの一実施例と、この制御動作プログラムに基づく照明器具の調光制御動作特性について、それぞれ図２および図３を参照しながら説明する。
【００２２】
図２は、本発明に係る照明制御装置の制御動作プログラムを示すフローチャート図である。図２において、まず制御対象となる照明器具の目標照度値Ｌp と、調光度の下限で点灯した時の前記照明器具のみによる床面照度値Ｌ0 については、予め設定値をそれぞれ照明制御装置に入力し記憶させておく。次に、照度センサを使用して室内等の床面の照度値Ｌを測定し、予め記憶した目標照度値Ｌp になるように照明器具の光束を調整し、床面の照度を一定に保持するよう制御が行われる（ＳＴＥＰ−１）。
【００２３】
そこで、前記照度センサにより検出される照度値Ｌが、調光度の下限になった場合において、その時の照度値Ｌm を検出すると共に、この検出された照度値Ｌm から前記目標照度値Ｌp を減算（Ｌm −Ｌp ）し、この値が前記照明器具のみによる床面照度値Ｌ0 よりも等しいかあるいは大きいか（Ｌm −Ｌp ≧Ｌ0 ）を判定する（ＳＴＥＰ−２）。そして、前記減算値（Ｌm −Ｌp ）が、床面照度値Ｌ0 よりも等しいかあるいは大きい場合には、照明器具を消灯制御する（ＳＴＥＰ−３）。
【００２４】
一方、前記減算値（Ｌm −Ｌp ）が、床面照度値Ｌ0 よりも小さい場合には、図６に示したように、前記照度値Ｌm と床面照度値Ｌ0 との関係から外光の照度値Ｌa （＝Ｌm −Ｌ0 ）が求められることから、この外光の照度値Ｌa が前記照度値Ｌm より大きいか（Ｌa ＞Ｌm ）を判定する（ＳＴＥＰ−４）。そして、前記外光の照度値Ｌa が照度値Ｌm より大きい場合には、照明器具を出力減少制御する（ＳＴＥＰ−５）。これに対し、前記外光の照度値Ｌa が照度値Ｌm より小さい場合には、照明器具を出力増加制御する（ＳＴＥＰ−６）。このようにして、前述した制御を繰り返し実行することにより、本発明に係る照明制御を円滑に達成することができる。
【００２５】
なお、前述した照明器具を消灯制御する操作において（ＳＴＥＰ−３）、照度センサによって検出される前記照度値Ｌm は、外光の照度値Ｌa と調光度の下限で点灯した時の前記照明器具のみによる床面照度値Ｌ0 との和（Ｌm ＝Ｌa ＋Ｌ0 ）から求められることから（図６参照）、前記演算式（Ｌm −Ｌp ≧Ｌ0 ）による関係は、演算式（Ｌa ≧Ｌp ）に変形することができる。すなわち、照度センサによって検出される前記照度値Ｌm に基づいて算出される外光の照度値Ｌa が、目標照度値Ｌp と等しいかあるいは大きい場合（Ｌa ≧Ｌp ）には、照明器具を消灯制御するように設定することもできる（ＳＴＥＰ−３）。
【００２６】
そして、図３は、前記照明制御装置における制御動作プログラムに基いて、照明器具の調光制御を行った場合の一実施例を示す調光制御動作特性線図である。すなわち、図３においては、所要の経過時間における目標照度値Ｌp に対する照度センサにより検出される照度値Ｌm と、外光の照度値Ｌa と、調光度との関係をそれぞれ示すものである。しかるに、目標照度値Ｌp は６００ｌｘ．であり、照明器具を全点灯すると８００ｌｘ．の照度が得られるものとする。そして、この照明器具に対する調光度の下限は、全光に対し２５％であるとする。これにより、調光度の下限で照明器具による照度値Ｌm は、２００ｌｘ．が得られることになる。
【００２７】
図３において、時刻１〜７では、外光の照度値Ｌa は時間の経過に伴って上昇していき、照明器具の調光度が低下していって、照度値は一定に保持されている。さらに、外光の照度値Ｌa が上昇していくと、時刻７〜８において、照明器具の調光度の下限において、照度値は外光の照度値Ｌa との合計が目標照度値Ｌp を越えてしまう。そして、時刻９において、検出された照度値が、調光度の下限における照明器具の照度値Ｌ0 に、目標照度値Ｌp を加えた値（Ｌ0 ＋Ｌp ）を越えた照度値Ｌm となる。すなわち、前記照度値Ｌm から目標照度値Ｌp を減算した値（Ｌm −Ｌp ）が、調光度の下限における照明器具の照度値Ｌ0 を越えた値（Ｌm −Ｌp ≧Ｌ0 ）となる。従って、この時刻９において、照明器具が消灯制御され、照度値は外光によるもののみとなる。
【００２８】
次いで、時刻１３において、外光の照度値Ｌa が低下し、目標照度値Ｌp を下回ると、照明器具が点灯制御される。この場合、照明器具は調光度の下限で点灯されるため、その照度値Ｌm は目標照度値Ｌp と調光度の下限における照明器具の照度値Ｌ0 との和（Ｌp ＋Ｌ0 ）となり、目標照度値Ｌp を上回っている。従って、その後の調光制御では、時刻の経過と共に照度値は、外光の照度値Ｌa の変化と共に目標照度値Ｌp （＝Ｌa ＋Ｌ0 ）まで低下していく。
【００２９】
図４は、制御対象となる照明器具について、調光度の下限における照度値Ｌ0 を求める場合の説明図である。すなわち、調光度の下限において点灯した時の照明器具の床面照度値Ｌ0 としては、照明器具の調光制御特性線上において、少なくとも任意の２点の調光度（Ｄ1 →Ｄ2 ）により点灯した場合の照度値（Ｌ1 →Ｌ2 ）から、その変化率（勾配）［Ｌ0 ＝（Ｌ2 −Ｌ1 ／Ｄ2 −Ｄ1 ）］を算出し、この変化率（勾配）に基づいて調光度の下限（例えば全光に対する２５％となる時点）での照度値Ｌ0 を求めることにより、容易に算出することができる。また、この場合、前記少なくとも任意の２点の調光度のうち１点の調光度（Ｄ1 ）は、照明器具の調光度の下限（消灯動作点）に設定することができる。
【００３０】
以上、本発明の好適な実施例について説明したが、本発明は前記実施例に限定されることなく、本発明の精神を逸脱しない範囲内において、種々の設計変更を行うことができる。
【００３１】
【発明の効果】
前述した実施例から明らかな通り、本発明に係る照明制御装置によれば、照度センサを使用して床面の照度値を測定し、予め記憶した目標照度値になるように照明器具の光束を調整し、床面の照度を一定に保持するよう制御するように構成した照明制御装置において、照明器具を調光度の下限で動作させている際に、その時点の外光を含む照度値Ｌm から、目標照度値Ｌp を減じた値が、調光度の下限で点灯した時の照明器具のみによる床面照度値Ｌ0 と、等しいかあるいは大きい場合（Ｌm −Ｌp ≧Ｌ0 ）には、照明器具を消灯制御するよう構成することにより、省エネルギー効果を簡便かつ有効に発揮させることができる。
【００３２】
また、本発明に係る照明制御装置においては、前記床面照度値Ｌ0 としては、照明器具の調光制御特性線上において、少なくとも任意の２点の調光度により点灯した場合の照度値から、その変化率（勾配）を算出し、この変化率（勾配）に基づいて調光度の下限（例えば、全光に対する２５％となる時点）での照度値Ｌ0 を求めることにより、容易に算出することができる。
【図面の簡単な説明】
【図１】本発明に係る照明制御装置の調光制御特性を示す特性線図である。
【図２】本発明に係る照明制御装置の制御動作プログラムの一実施例を示すフローチャート図である。
【図３】従来の照明制御装置の調光制御動作の一実施例を示す調光制御動作特性線図である。
【図４】本発明に係る照明制御装置の調光制御特性を示す特性線図において、調光度の下限で点灯した際の照明器具のみによる床面照度値Ｌ0 を算出するための説明図である。
【図５】従来の照明制御装置のシステム構成例を示す説明図である。
【図６】一般的な照明器具の照明制御装置による調光制御特性線図である。
【符号の説明】
Ｌm 調光度の下限における照度値
Ｌp 目標照度値
Ｌ0 調光度の下限で点灯した照明器具のみによる照度値
Ｌa 外光の照度値[0001]
BACKGROUND OF THE INVENTION
The present invention measures the illuminance value of the floor using an illuminance sensor, adjusts the luminous flux of the luminaire so as to obtain a pre-stored target illuminance value, and controls to keep the illuminance of the floor constant. In the lighting control device configured as described above, the illuminance value when the lighting fixture is operated at the lower limit of the dimming degree when the dimming control is performed at the lower limit of the dimming degree may exceed the target illuminance value even when the lighting fixture is turned off. It is related with the illumination control apparatus comprised so that it might determine that there existed extraneous light and performs light extinction control.
[0002]
[Prior art]
Conventionally, an illumination control device configured to detect the illuminance of the floor surface with reflected light from the floor surface using an illuminance sensor, and to perform constant illuminance control on the luminaire based on the detection value by the illuminance sensor, It is known. FIG. 5 is an explanatory diagram showing a configuration example of a setting state of the lighting control device, and a ceiling 12 substantially parallel to the floor surface 10 is provided above the floor surface 10 at a predetermined distance. The ceiling 12 is provided with a lighting fixture 14 composed of a fluorescent lamp and the like, and an illuminance sensor 16 for detecting the brightness of the irradiation area of the lighting fixture 14. An illumination control device 20 is connected to the illuminance sensor 16, and a lighting fixture 14 is connected to the illumination control device 20.
[0003]
However, in general, the brightness in the vicinity of the ceiling 12 detected by the illuminance sensor 16, that is, the illuminance value L, is obtained when the luminous flux Φ emitted from the lighting fixture 14 reaches the floor surface 10 when there is no luminous flux other than the lighting fixture 14. The light flux reflected from the floor surface 10 with the reflection coefficient κ is obtained as the light flux per unit area that reaches the ceiling 12.
[0004]
Therefore, when the illuminance sensor 16 is arranged on the ceiling 12, the brightness of the floor surface 10 to be measured, that is, the illuminance value L varies depending on the reflection coefficient κ. For this reason, the illuminance value on the floor surface 10 is detected using an illuminance meter separate from the illuminance sensor 16, and the reflection coefficient κ of the floor surface 10 is calculated from the difference in illuminance value between the illuminance meter and the illuminance sensor 16. The illuminance, that is, the brightness of the lighting fixture 14 can be set using this reflection coefficient κ.
[0005]
However, in a lighting fixture that is actually placed in a room such as a building, when dimming control is performed by a lighting control device, when measuring the illuminance value of the floor surface with an illuminance sensor, the brightness of the lighting fixture is adjusted. The brightness of outside light will be added. Also, when using a dimmable lighting fixture, as shown in FIG. 6, the dimmable control range by the dimming device has a certain lower limit, not off to full light (100% on). There are many cases. In particular, when the fluorescent lamp is driven by an inverter, the lower limit value of the dimmable control range is often about 25% to 50% with respect to the total light.
[0006]
In general, since the illuminance is proportional to the amount of light flux per area, in the typical dimming control characteristic of the luminaire shown in FIG. 6, the illuminance value in the dimmable control range is the luminous flux from the luminaire. Is proportional to the sum of the other luminous fluxes (mostly ambient light). Accordingly, the illuminance value is proportional to the dimming degree within the control range (between the lower limit and the total light) of the lighting fixture. Then, when the dimming control range is below the lower limit of the dimmable control range, the illuminance value is obtained only by outside light because the light is turned off. In this case, the illuminance value Lm at the lower limit of the dimmable control range is the brightness of the outside light (illuminance value La) and the brightness of only the luminaire when lit at the lower limit of the dimmable control range. It is expressed by the sum (Lm = La + L0) with (illuminance value L0).
[0007]
[Problems to be solved by the invention]
In the conventional lighting control device having such dimming control characteristics, the relationship between the target illuminance value Lp and the illuminance values (L1, L2, L3) when the illuminance value La due to external light changes due to the dimming operation is shown. If shown, it is as shown in FIG.
[0008]
That is, in FIG. 1, the target illuminance value Lp is first set. Therefore, in the case of the dimming control characteristic a as shown by the solid line, the relationship between the illuminance value Lm at the lower limit of the dimming degree and the illuminance value La of the external light at that time is Lm−L0 = La. In this case, as described above, the illuminance value L0 is the floor illuminance value L0 obtained only by the luminaire when lit at the lower limit of the dimming degree, and is a characteristic value unique to the luminaire. In the dimming control characteristic a, since the illuminance value La of the external light is lower than the target illuminance value Lp, it is not preferable to turn off the lighting fixture. Next, in the case of the dimming control characteristic b as shown by the broken line, the relationship between the illuminance value Lm ′ at the lower limit of the dimming degree and the illuminance value La ′ of the external light at that time is Lm′−L0 ′ = La ′. It is. In the dimming control characteristic b, since the illuminance value La ′ of the external light is further lower than the target illuminance value Lp, it is not preferable to turn off the lighting fixture. Further, in the case of the dimming control characteristic c as shown by the dotted line, the relationship between the illuminance value Lm "at the lower limit of the dimming degree and the illuminance value La" of the external light at that time is Lm "-L0" = La ". In the dimming control characteristic c, since the illuminance value La ″ of the outside light exceeds the target illuminance value Lp, it is preferable to turn off the lighting fixture.
[0009]
Therefore, as a result of various studies, the present inventors have conducted illuminance values (Lm including external light at the time when the lighting fixture is operated at the lower limit of the dimming degree as in the case of the dimming control characteristic c described above. ), The value obtained by subtracting the target illuminance value (Lp) is equal to or larger than the floor illuminance value (L0) obtained only by the lighting fixture when the light is lit at the lower limit of the dimming degree (Lm-Lp ≧ L0). Found that it would be effective if the lighting fixture was configured to be controlled to turn off.
[0010]
Further, in this case, the floor illuminance value (L0) by only the lighting fixture when the lighting is performed at the lower limit of the dimming degree is at least two arbitrary dimming control points in the dimming control characteristics of the lighting fixture to be controlled. The rate of change (gradient) [L0 = (L2-L1 / D2-D1)] is obtained from the illuminance value (L1-> L2) when the light is lit at the luminous intensity (D1-> D2), and the rate of change (gradient) is obtained. Based on the lower limit of the dimming degree, the illuminance value when the lighting fixture is turned on can be calculated easily.
[0011]
Accordingly, an object of the present invention is to measure the illuminance value of the floor using an illuminance sensor, adjust the luminous flux of the luminaire so as to be a pre-stored target illuminance value, and keep the illuminance of the floor constant. In the lighting control device configured to control the lighting control, if the illuminance value of the external light at that time exceeds the target illuminance value at the time of the dimming control at the lower limit of the dimming degree, the lighting fixture is turned off to save energy An object of the present invention is to provide an illumination control device that can easily and effectively exhibit the above.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the illumination control device according to the present invention measures the illuminance value of the floor using an illuminance sensor, adjusts the luminous flux of the luminaire so as to obtain a pre-stored target illuminance value, and In the illumination control device configured to control to keep the illuminance of the surface constant, from the illuminance value when lit at at least two arbitrary dimming levels, only by the lighting fixture when lit at the lower limit of the dimming level When the floor surface illuminance L0 is calculated and the lighting fixture is operated at the lower limit of the dimming level, the value obtained by subtracting the target illuminance value Lp from the illuminance value Lm including the external light at that time is the lower limit of the dimming level When it is equal to or larger than the floor surface illuminance value L0 when only the lighting fixture is lit (Lm−Lp ≧ L0), the lighting fixture is controlled to be turned off, and the lighting fixture is controlled to be turned off. When the illuminance value La falls below the target illuminance value Lp Characterized by the lighting control.
[0013]
Further, when the lighting fixture is operated at the lower limit of the dimming degree, the illuminance value Lm including the external light at that time and the floor illuminance value L0 by the lighting fixture only when the lighting fixture is turned on at the lower limit of the dimming degree. When the required illuminance value La (= Lm−L0) of external light is equal to or larger than the target illuminance value Lp (La ≧ Lp), the lighting apparatus can be controlled to be turned off.
[0015]
In this case, one dimming degree among the at least two arbitrary dimming degrees can be set to a lower limit (light-off operating point) of the dimming degree of the lighting fixture.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of a lighting control device according to the present invention will be described in detail below with reference to the accompanying drawings.
[0019]
As shown in FIG. 1 described above, the illumination control device according to the present invention first sets the target illuminance value Lp, and in the case of the dimming control characteristic c as shown by the dotted line, the illuminance value Lm ″ at the lower limit of the dimming degree. And the illuminance value La ″ of the external light at that time is Lm ″ −L0 ″ = La ″, the illuminance value La ″ of the external light is the target illuminance value Lp in the dimming control characteristic c. Therefore, the lighting fixture is configured to be controlled to be turned off.
[0020]
On the other hand, in the illumination control apparatus according to the present invention, in FIG. 1, for example, in the case of the dimming control characteristic a as shown by the solid line, the relationship between the illuminance value Lm at the lower limit of the dimming degree and the illuminance value La of the external light at that time Lm -L0 = La. In this case, as described above, the illuminance value L0 is the floor illuminance value L0 obtained only by the luminaire when lit at the lower limit of the dimming degree, and is a characteristic value unique to the luminaire. In the dimming control characteristic a, since the illuminance value La of the external light is lower than the target illuminance value Lp, the lighting fixture is not controlled to be turned off. In the case of the dimming control characteristic b as shown by the broken line, the relationship between the illuminance value Lm ′ at the lower limit of the dimming degree and the illuminance value La ′ of the external light at that time is Lm′−L0 ′ = La ′. In the dimming control characteristic b, since the illuminance value La ′ of the external light is further lower than the target illuminance value Lp, the lighting fixture is not controlled to be turned off as described above.
[0021]
Therefore, an example of the control operation program of the lighting control apparatus according to the present invention described above and the dimming control operation characteristics of the lighting fixture based on the control operation program will be described with reference to FIGS. 2 and 3, respectively.
[0022]
FIG. 2 is a flowchart showing a control operation program of the illumination control apparatus according to the present invention. In FIG. 2, first, a preset value is input to the lighting control device in advance for the target illuminance value Lp of the luminaire to be controlled and the floor illuminance value L0 by only the luminaire when lit at the lower limit of the dimming degree. And remember it. Next, the illuminance sensor is used to measure the illuminance value L of the floor surface in the room or the like, and the luminous flux of the lighting fixture is adjusted so as to become the pre-stored target illuminance value Lp, thereby maintaining the illuminance of the floor surface constant. Control is performed (STEP-1).
[0023]
Therefore, when the illuminance value L detected by the illuminance sensor becomes the lower limit of the dimming degree, the illuminance value Lm at that time is detected, and the target illuminance value Lp is subtracted from the detected illuminance value Lm ( Lm-Lp), and it is determined whether this value is equal to or greater than the floor surface illumination value L0 (Lm-Lp.gtoreq.L0) (STEP-2). When the subtracted value (Lm-Lp) is equal to or greater than the floor illuminance value L0, the lighting fixture is controlled to be turned off (STEP-3).
[0024]
On the other hand, when the subtracted value (Lm−Lp) is smaller than the floor surface illuminance value L0, as shown in FIG. 6, the illuminance of external light is determined from the relationship between the illuminance value Lm and the floor surface illuminance value L0. Since the value La (= Lm−L0) is obtained, it is determined whether the illuminance value La of the external light is larger than the illuminance value Lm (La> Lm) (STEP-4). When the illuminance value La of the external light is larger than the illuminance value Lm, the lighting fixture is subjected to output reduction control (STEP-5). On the other hand, when the illuminance value La of the external light is smaller than the illuminance value Lm, the output of the lighting fixture is controlled (STEP-6). Thus, the illumination control according to the present invention can be smoothly achieved by repeatedly executing the above-described control.
[0025]
In the above-described operation for turning off the lighting fixture (STEP-3), the illuminance value Lm detected by the illuminance sensor is only the luminaire when the illuminance value La of the external light and the dimming level are turned on. Is obtained from the sum (Lm = La + L0) with the floor illuminance value L0 (see FIG. 6), the relationship according to the arithmetic expression (Lm−Lp ≧ L0) is transformed into the arithmetic expression (La ≧ Lp). be able to. That is, when the illuminance value La of the external light calculated based on the illuminance value Lm detected by the illuminance sensor is equal to or larger than the target illuminance value Lp (La ≧ Lp), the lighting fixture is controlled to be turned off. (STEP-3).
[0026]
FIG. 3 is a dimming control operation characteristic diagram illustrating an embodiment when dimming control of the lighting fixture is performed based on a control operation program in the lighting control device. That is, FIG. 3 shows the relationship between the illuminance value Lm detected by the illuminance sensor with respect to the target illuminance value Lp at the required elapsed time, the illuminance value La of external light, and the dimming degree. However, the target illuminance value Lp is 600 lx. When the lighting fixture is fully lit, 800 lx. The illuminance of And let the minimum of the light control degree with respect to this lighting fixture be 25% with respect to all the lights. Thereby, the illuminance value Lm by the lighting fixture at the lower limit of the dimming degree is 200 lx. Will be obtained.
[0027]
In FIG. 3, at times 1 to 7, the illuminance value La of external light increases with time, the dimming degree of the luminaire decreases, and the illuminance value is held constant. Further, when the illuminance value La of the external light increases, at the time 7 to 8, at the lower limit of the dimming degree of the luminaire, the illuminance value exceeds the target illuminance value Lp with the illuminance value La of the external light. End up. At time 9, the detected illuminance value becomes an illuminance value Lm that exceeds a value (L0 + Lp) obtained by adding the target illuminance value Lp to the illuminance value L0 of the lighting fixture at the lower limit of the dimming degree. That is, a value (Lm−Lp) obtained by subtracting the target illuminance value Lp from the illuminance value Lm is a value exceeding the illuminance value L0 of the lighting fixture at the lower limit of the dimming degree (Lm−Lp ≧ L0). Therefore, at this time 9, the lighting fixture is controlled to be turned off, and the illuminance value is only due to external light.
[0028]
Next, at time 13, when the illuminance value La of the external light decreases and falls below the target illuminance value Lp, the lighting fixture is controlled to turn on. In this case, since the luminaire is turned on at the lower limit of the dimming degree, the illuminance value Lm is the sum (Lp + L0) of the illuminance value L0 of the luminaire at the lower limit of the dimming degree and the target illuminance value Lp. Is over. Accordingly, in the subsequent dimming control, the illuminance value decreases to the target illuminance value Lp (= La + L0) with the change of the illuminance value La of the external light as time elapses.
[0029]
FIG. 4 is an explanatory diagram for obtaining the illuminance value L0 at the lower limit of the dimming degree for the lighting fixture to be controlled. That is, the floor surface illuminance value L0 of the lighting fixture when it is turned on at the lower limit of the dimming degree is the case where it is turned on by at least two arbitrary dimming degrees (D1 → D2) on the dimming control characteristic line of the lighting fixture. The rate of change (gradient) [L0 = (L2−L1 / D2−D1)] is calculated from the illuminance value (L1 → L2), and based on this rate of change (gradient), the lower limit of dimming (for example, for all light) By calculating the illuminance value L0 at the time of 25%, it can be easily calculated. In this case, the dimming degree (D1) of one of the at least two arbitrary dimming degrees can be set to the lower limit (the extinction operating point) of the dimming degree of the lighting fixture.
[0030]
Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the spirit of the present invention.
[0031]
【The invention's effect】
As is apparent from the above-described embodiments, according to the illumination control device of the present invention, the illuminance sensor is used to measure the illuminance value of the floor surface, and the luminous flux of the luminaire is adjusted so as to obtain a pre-stored target illuminance value. In the lighting control device configured to adjust and control the illuminance of the floor to be kept constant, when the lighting fixture is operated at the lower limit of the dimming degree, from the illuminance value Lm including the external light at that time When the value obtained by subtracting the target illuminance value Lp is equal to or larger than the floor surface illuminance value L0 when only the lighting device is turned on at the lower limit of the dimming degree (Lm−Lp ≧ L0), the lighting device is turned off. By configuring to control, the energy saving effect can be easily and effectively exhibited.
[0032]
Further, in the lighting control device according to the present invention, the floor surface illuminance value L0 changes from the illuminance value when the lighting is performed with at least two arbitrary dimming levels on the dimming control characteristic line of the lighting fixture. The rate (gradient) is calculated, and the illuminance value L0 at the lower limit of the dimming degree (for example, when it becomes 25% of the total light) is calculated based on the change rate (gradient). .
[Brief description of the drawings]
FIG. 1 is a characteristic diagram showing dimming control characteristics of a lighting control apparatus according to the present invention.
FIG. 2 is a flowchart showing one embodiment of a control operation program of the illumination control apparatus according to the present invention.
FIG. 3 is a dimming control operation characteristic diagram showing an embodiment of a dimming control operation of a conventional lighting control device.
FIG. 4 is an explanatory diagram for calculating a floor illuminance value L0 only by a lighting fixture when the lighting control device according to the present invention is turned on at the lower limit of the dimming degree in the characteristic diagram showing the dimming control characteristic. .
FIG. 5 is an explanatory diagram showing a system configuration example of a conventional lighting control device.
FIG. 6 is a light control characteristic diagram of a lighting control device for a general lighting fixture.
[Explanation of symbols]
Lm Illuminance value at the lower limit of dimming level Lp Target illuminance value L0 Illuminance value by only the luminaire lit at the lower limit of dimming intensity La Illuminance value of outside light

Claims

Illumination configured to measure the illuminance value of the floor using an illuminance sensor, adjust the luminous flux of the luminaire so as to be a pre-stored target illuminance value, and control the illuminance of the floor to be kept constant In the control device,
From the illuminance value when the light is lit at least at any two dimming levels, the floor illuminance L0 is calculated only from the lighting fixture when lit at the lower limit of the dimming level,
When operating the luminaire at the lower limit of the dimming level, the value obtained by subtracting the target illuminance value Lp from the illuminance value Lm including the external light at that time depends only on the luminaire when it is lit at the lower limit of the dimming level When the illuminance value L0 is equal to or larger than the floor illuminance value L0 (Lm−Lp ≧ L0) , the lighting device is controlled to be turned off, and the illuminance value La of the external light is the target illuminance value Lp when the lighting device is controlled to be turned off. The lighting control device is characterized in that lighting control of the lighting fixture is performed when the value is below .

When the lighting fixture is operated at the lower limit of the dimming degree, it is obtained from the illuminance value Lm including the external light at that time and the floor illuminance value L0 by the lighting fixture only when the lighting fixture is turned on at the lower limit of the dimming degree. 2. The illumination control according to claim 1, wherein when the illuminance value La (= Lm−L0) of the external light is equal to or larger than the target illuminance value Lp (La ≧ Lp), the lighting fixture is controlled to be turned off. apparatus.

The lighting control device according to claim 1 or 2, wherein one of the at least two arbitrary dimming levels is set to a lower limit (light-off operating point) of the dimming level of the lighting fixture .