JP2011086587A - Illumination control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable stable illumination dimming of various illumination loads having differing ripple periods, and to reduce cost. <P>SOLUTION: The illumination control system 1 is structured of an illumination device 2, equipped with an illumination load 20, an illumination circuit section 21, a calculating section 23, a smoothing circuit section 24, a storage section 25 and a control section 26, and a brightness sensor 3. The smoothing circuit section 24, equipped with integrated circuits 24a to 24e having differing time constants, smoothes a voltage value of the brightness sensor 3. The control section 26 is provided with a normal mode of controlling the illumination load 20 to light on, and a measurement mode of measuring ripple periods of the voltage value. The storage section 25 stores a table showing ripple period information, and time constant information of the integrated circuits 24a, to 24e each corresponding to the ripple periods. The control section 26 determines which ripple period in the table the ripple period measured corresponds to, selects an integrated circuit of a corresponding time constant, and controls so as to smooth the voltage value with the integrated circuit at normal mode. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an illumination control system that controls lighting of one or more illumination devices.

Conventionally, from one or more lighting devices installed on a ceiling surface in an office building or public facility, and a brightness sensor that detects illuminance in the lighting space and outputs the result as a voltage value to the lighting device. A configured lighting control system is provided (see, for example, Patent Document 1). The lighting device includes a lighting load, a lighting circuit unit that lights the lighting load, a calculation unit that calculates a dimming rate according to a voltage value input from the brightness sensor, and a lighting load that lights the lighting load at the dimming rate And a control unit for controlling the lighting circuit unit.

Such an illumination control system changes the dimming rate so that the desk top surface has a desired illuminance while the daylight in the illumination space is blocked as an initial setting, and the voltage input from the brightness sensor at that time The value (reference value) needs to be stored in the lighting device. Thus, the control unit controls to decrease the current dimming rate when the voltage value input from the brightness sensor is greater than the reference value with respect to the current illuminance, and when the voltage value is smaller than the reference value, Control to increase the dimming rate.
Accordingly, the lighting device installed near the window side where the illuminance is likely to increase due to the incidence of daylight can effectively reduce the dimming rate and save energy.

By the way, if the above-mentioned illumination load is, for example, a fluorescent lamp, a high-frequency voltage generated by a lighting circuit unit having an inverter circuit as a main component is applied to the fluorescent lamp. Therefore, high frequency (
Even if the brightness sensor detects the illuminance in the illumination space with respect to the illumination load that is lit at 40 kHz, for example, the voltage value output from the brightness sensor varies as shown in FIG. It becomes almost constant and the calculated dimming rate is stable.

On the other hand, when the illumination load is a light emitting diode (LED), a DC voltage generated by a lighting circuit unit including a rectifier circuit or a converter circuit as a main component is applied to the LED. Here, dimming lighting of the LED is performed by repeating an on period in which the LED is lit at a predetermined frequency (for example, 50 Hz) and an off period in which the LED is turned off. When the dimming rate is changed, the voltage ratio between the on period and the off period is adjusted, so that the light output of the illumination load at the time of dimming lighting changes with a relatively long cycle of, for example, 20 ms. Will do. Therefore, depending on the timing at which the brightness sensor detects the illuminance in the illumination space, the output voltage value has a periodic variation (ripple) as shown in FIG. 9, and is calculated as a result. There was a risk that the dimming rate would be unstable.

On the other hand, the voltage value output from the brightness sensor in the control unit is sampled at a constant period to obtain an average value, and the calculation unit calculates the dimming rate according to the average value. A lighting control system that realizes stable dimming is provided.

The predetermined frequency differs depending on the type of lighting load. If lighting loads of the same type are used, even if the dimming rate changes by adjusting the voltage ratio between the on period and the off period, 9 has a constant ripple period (hereinafter referred to as a ripple period).

JP 2005-71776 A

However, in the conventional lighting control system, if the type of lighting load is changed, the predetermined frequency at the time of dimming lighting is also different, so the ripple period of the voltage value output from the brightness sensor is also different, and the control unit is limited. Because it is only possible to deal with lighting loads having a specified ripple period, it is necessary to prepare another control unit corresponding to the ripple period for lighting loads having a different ripple period, and the same member cannot be reused. There was a problem of high costs.

The present invention has been made in view of the above reasons, and the object thereof is to realize stable dimming with respect to various illumination loads having different ripple periods, and to achieve cost reduction. It is to provide a lighting control system.

In order to achieve the above object, the invention of claim 1 is composed of one or more illumination devices and a brightness sensor that detects the illuminance in the illumination space and outputs the result as a voltage value to the illumination device. The lighting control system includes a lighting load, a lighting circuit unit that turns on the lighting load, and a plurality of integration circuits having different time constants, and smoothes a voltage value input from a brightness sensor. A smoothing circuit unit, a calculation unit that calculates a dimming rate according to the voltage value smoothed by the smoothing circuit unit, and a normal mode that controls the lighting circuit unit to light the illumination load at the dimming rate, or brightness A table representing a control unit that operates in a measurement mode for measuring a ripple period of a voltage value input from a sensor, information on a plurality of ripple periods, and information on a time constant of the integration circuit corresponding to each of the ripple periods Write And a control unit that determines a ripple period in the table corresponding to the ripple period measured by referring to the table of the storage unit in the measurement mode and corresponding to the ripple period. The smoothing circuit unit is controlled so that the voltage value input from the brightness sensor is smoothed by the selected integrating circuit in the normal mode.

According to the present invention, an integration circuit having a time constant corresponding to the measured ripple period is selected from a plurality of integration circuits in the measurement mode, and is input from the brightness sensor by the selected integration circuit in the normal mode. Since the smoothing circuit unit is controlled so as to smooth the voltage value, stable dimming can be realized for various illumination loads having different ripple periods, and cost reduction can be achieved.

According to a second aspect of the present invention, in the first aspect of the invention, when the ripple period measured with reference to the table of the storage unit in the measurement mode is near the boundary between the two ripple periods in the table, An integration circuit having a smaller time constant is selected from two integration circuits corresponding to two ripple periods.

According to the present invention, when the ripple period measured in the measurement mode is in the vicinity of the boundary between the two ripple periods in the table, the integration with the smaller time constant of the two integration circuits corresponding to the two ripple periods is performed. Since the circuit is selected, the charging / discharging time of the capacitor of the integrating circuit is shortened in the normal mode, and the dimming rate can be changed more quickly and the responsiveness can be improved.

In the present invention, there is an effect that stable dimming can be realized for various illumination loads having different ripple periods, and cost can be reduced.

It is a block diagram of the illuminating device of embodiment of this invention. It is the whole block diagram same as the above. It is a block diagram of the principal part in the same as the above. It is a characteristic view which shows the change of the applied voltage with respect to time passage in the same as the above. It is a characteristic view which shows the change of the optical output with respect to time passage in the same as the above. It is explanatory drawing when measuring the ripple period in the same as the above. (A)-(c) is a characteristic view which shows the change of the voltage value of the brightness sensor with respect to time passage for every light control rate in the same as the above. It is explanatory drawing in case an illumination load is a fluorescent lamp in an example of the conventional illumination control system. It is explanatory drawing in case the illumination load in the same is a light emitting diode.

Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, the lighting control system 1 of the present embodiment includes a plurality of lighting devices 2 (only one is shown in FIG. 1) installed on a ceiling surface in an office building or a public facility. The brightness sensor 3 is connected to each other through one signal line 4. The lighting device 2 is supplied with electric power for driving each unit and brightness sensor 3 described later from a commercial AC power supply via a power line (not shown).

As shown in FIGS. 1 and 2, the brightness sensor 3 detects the illuminance in the illumination space and outputs the result as a voltage value to each illuminating device 2 through the signal line 4, and an illuminance detector (not shown) And a control unit and a communication unit. The illuminance detection unit is configured by a circuit including a light receiving element that performs photoelectric conversion, the control unit is configured by a microprocessor, and the communication unit is RS48.
It consists of a two-wire serial communication circuit that conforms to 5 etc. In addition, the brightness sensor 3 of this embodiment
Is installed directly on the ceiling surface and is electrically connected to the illuminating device 2 via the signal line 4. However, the present invention is not limited to this. It may be a plug-in type that is mechanically and electrically connected.

As shown in FIG. 1, the lighting device 2 includes a lighting load 20, a lighting circuit unit 21 that lights the lighting load 20, and a communication unit 22. The lighting load 20 includes one or more light emitting diodes (LEDs).
). The lighting circuit unit 21 includes, for example, a rectifier circuit that rectifies a voltage supplied from a commercial AC power source and a converter circuit that converts the rectified voltage into a DC voltage. The communication unit 22 has the same type of communication circuit configuration as a communication unit (not shown) of the brightness sensor 3 and communicates with the brightness sensor 3 through the signal line 4. For the signal line 4, a serial communication cable adapted to these is used. The communication unit 22 preferably uses a control method (for example, CSMA / CA) having a function of avoiding signal collision.

Moreover, the illuminating device 2 is provided with the calculating part 23, the smoothing circuit part 24, the memory | storage part 25, and the control part 26 in addition to the above, as shown in FIG.1 and FIG.3. The calculation unit 23 is composed of a microprocessor or the like, and calculates the dimming rate. As shown in FIG. 3, the smoothing circuit unit 24 includes five integrating circuits 24 a to 24 e that are connected in parallel to the electric circuit a, and smoothes the voltage value input from the brightness sensor 3 via the communication unit 22. To do. Here, the integrating circuits 24a to 24e are low-pass filters each composed of a resistor and a capacitor (not shown), and are set so that each time constant is different. Further, the smoothing circuit unit 24 has five switches (not shown) that are turned on / off by the control unit 26 to be conductive / non-conductive between both ends of the integrating circuits 24a to 24e.
Are provided.

The storage unit 25 includes, for example, an EEPROM, a flash memory, or the like, and stores a table representing a plurality of ripple period information and time constant information of the integration circuits 24a to 24e corresponding to the ripple periods. In addition, the ripple period said here is the period of the ripple which the voltage value output to the illuminating device 2 from the brightness sensor 3 has as described in the prior art. The ripple period in the table of the present embodiment is stored in five ranges.
That is, the first period (10 μs or less), the second period (10 μs to 1 ms), the third period (1 ms to 10 ms), the fourth period (10 ms to 100 ms), the fifth period (100 ms)
These are the five ranges, and these are the integration circuits 24a, 24b, 24c, 24d, 24e.
Are sequentially associated with the time constants. The time constant is the smallest in the integration circuit 24a and is 2
It is set to increase in the order of 4b, 24c,. In addition to the above-described table, the storage unit 25 also stores a voltage value serving as a reference value when calculating the dimming rate described in the related art.

The control unit 26 is configured by a microprocessor or the like, and has two operation modes, a normal mode and a measurement mode. In the normal mode, the voltage value smoothed through the smoothing circuit unit 24 is output to the calculation unit 23, and the lighting circuit unit 21 is turned on so that the lighting load 20 is lit at the calculated dimming rate.
This is the mode to control. On the other hand, the measurement mode is a mode in which the ripple period of the voltage value input from the brightness sensor 3 is measured. A detailed description of the method for measuring the ripple period will be given later.

Here, the control unit 26 of the present embodiment refers to the table of the storage unit 25 in the measurement mode,
It is determined which one of the first to fifth cycles in the table corresponds to the measured ripple cycle, and an integration circuit having a time constant corresponding to the cycle is selected from the integration circuits 24a to 24e. To do. Then, the control unit 26 controls the smoothing circuit unit 24 so that the voltage value input from the brightness sensor 3 is smoothed by the selected integration circuit in the normal mode. The operation mode of the present embodiment will be described as a measurement mode at the same time as the operation of the lighting control system 1 is started, and then automatically switched to the normal mode. An operation input unit (not shown) that receives an operation input for performing the operation may be provided in the lighting device 2 and may be manually performed via the operation input unit. Also,
A wireless communication unit (not shown) for receiving a wireless signal transmitted by operating a button on a remote controller (not shown) is provided in the lighting device 2, and the operation mode is switched using the wireless signal as a trigger signal. It may be a thing.

Hereinafter, operation | movement of the illumination control system 1 of this embodiment is demonstrated. First, for example, when the operation of the lighting control system 1 is started through an on / off operation of a switch (not shown) installed on the wall surface, the control unit 26 forcibly lights the lighting load 20 at a dimming rate of 75%. The lighting circuit unit 21 is controlled and the measurement mode is started. Here, as described in the prior art, L
The dimming lighting of the ED is performed by repeating an on period in which lighting is performed at a predetermined frequency (for example, 50 Hz) and an off period in which light is extinguished. When the dimming rate is changed, the voltage ratio between the on period and the off period is adjusted, so that the voltage applied to the lighting load 20 fluctuates with a relatively long period (for example, 20 ms). ing. Note that the voltage applied to the illumination load 20 that was originally a rectangular wave is smoothed by a capacitor or the like in the lighting circuit section 21 as shown in FIG. Accordingly, the light output of the illumination load 20 also has a relatively long period ripple as shown in FIG. Therefore, the voltage value output from the brightness sensor 3 to the lighting device 2 also has a ripple with the same period.

On the other hand, since the control unit 26 operates in the measurement mode, the control unit 26 measures the ripple period of the voltage value input from the brightness sensor 3. That is, the control unit 26 controls all the five switches (not shown) of the smoothing circuit unit 24 to be turned off so that the non-smoothed voltage value input from the brightness sensor 3 as shown in FIG. Sample continuously (see arrows in the figure). Then, the control unit 26 extracts the maximum value and the minimum value from the sampled voltage values, and calculates the ripple period by doubling the elapsed time from the maximum value to the minimum value. In the above description, all the five switches of the smoothing circuit unit 24 are controlled to be off. However, for example, the amplitude of the ripple of the voltage value is large and the maximum value exceeds the allowable voltage value, and the ripple period cannot be measured. In this case, the voltage value may be sampled after smoothing by controlling any one of the five switches.

If the measured ripple period is 8 ms, for example, the control unit 26 refers to the table in the storage unit 25 and determines that the ripple period corresponds to the third period (1 ms to 10 ms). A corresponding time constant integrating circuit 24c is selected. Next, the control unit 26 stores the information that the integration circuit 24c has been selected in the storage unit 25, and at the same time, automatically switches the operation mode from the measurement mode to the normal mode.

The control unit 26 acquires information from the storage unit 25 that the integration circuit 24c has been selected when the operation is started in the normal mode, and controls the switch to turn on only between both ends of the integration circuit 24c. The four switches are controlled to be off so that the both ends of the four integrating circuits 24a, 24b, 24d, and 24e are not conductive. That is, the control unit 26 controls the smoothing circuit unit 24 so that the voltage value input from the brightness sensor 3 is smoothed by the integrating circuit 24c. And the control part 26 outputs the voltage value smoothed through the integration circuit 24c, and the above-mentioned reference value memorize | stored in the memory | storage part 25 to the calculating part 23, and makes the lighting load 20 light with the calculated light control rate. Thus, the lighting circuit unit 21 is controlled.

As described above, the illumination control system 1 of the present embodiment measures the ripple period in the measurement mode, selects an integration circuit having a time constant corresponding to the ripple period from the integration circuits 24a to 24e, and selects the normal mode. Since the integration circuit is sometimes used for smoothing, stable dimming can be realized for various illumination loads 20 having different ripple periods, and cost reduction can be achieved.

In the above description, the measured ripple period is 8 ms. However, when the measured ripple period is, for example, 10 ms near the boundary between the third period and the fourth period, the controller 2
6 is set to select the integration circuit 24c having the smaller time constant among the integration circuits 24c and 24d corresponding to the third period and the fourth period, the smoothing circuit section 24 in the normal mode.
The charging / discharging time of the capacitor is shortened, and the dimming rate can be changed more quickly, and the responsiveness can be improved.

FIG. 7 is a characteristic diagram showing a change in voltage value of the brightness sensor 3 over time for each dimming rate of the illumination load 20, and FIG. 7 (a) shows a dimming rate of 100% and FIG. 7 (b). Is a dimming rate of 75%, and FIG. 7C is a dimming rate of 50%. As can be seen from FIG. 7, the amplitude of the ripple depends on the lighting load 20.
The amplitude differs depending on the dimming rate, and the amplitude of the ripple is nearly zero when the dimming rate is 100%. The ripple amplitude increases as the dimming rate decreases. Therefore, the control unit 26 controls the dimming rate 7 rather than starting the measurement mode when the lighting load 20 is 100% dimming.
The ripple period can be measured more accurately by starting at 5% or 50%.

DESCRIPTION OF SYMBOLS 1 Lighting control system 2 Lighting apparatus 3 Brightness sensor 20 Lighting load 21 Lighting circuit part 23 Calculation part 24 Smoothing circuit part 25 Memory | storage part 26 Control part

Claims (2)

An illumination control system including one or more illumination devices and a brightness sensor that detects illuminance in the illumination space and outputs the result as a voltage value to the illumination device,
An illumination device includes an illumination load, a lighting circuit unit that lights the illumination load, a smoothing circuit unit that has a plurality of integration circuits having different time constants and smoothes a voltage value input from a brightness sensor, and a smoothing circuit A calculation unit that calculates a dimming rate according to the voltage value smoothed by the unit, and a normal mode that controls the lighting circuit unit to light the illumination load at the dimming rate, or a voltage input from a brightness sensor A control unit that operates in a measurement mode for measuring the ripple period of the value, a storage unit that stores a table representing information on a plurality of ripple periods and information on the time constant of the integration circuit corresponding to each of the ripple periods, With
The control unit refers to the table in the storage unit in the measurement mode, determines which ripple cycle in the table corresponds to the ripple cycle, selects an integration circuit with a time constant corresponding to the ripple cycle, and An illumination control system that controls a smoothing circuit unit so that a voltage value input from a brightness sensor is smoothed by a selected integration circuit in a mode. When the ripple period measured with reference to the table in the storage unit in the measurement mode is in the vicinity of the boundary between the two ripple periods in the table, the control unit selects the time between the two integration circuits corresponding to the two ripple periods. 2. An integration circuit having a smaller constant is selected.
The lighting control system described.

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