JPH0498792A - dimming control device - Google Patents

Abstract

PURPOSE:To prevent the generation of difference in brightness of a lighting load, even when the balance of phase voltage of a polyphase current power source becomes unstable by correcting a dimming level of the lighting load, even when the voltage of the phase to which the lighting load is connected, is varied. CONSTITUTION:A signal from each fader F1-Fn is converted into a digital signal by an analog/digital conversion circuit 13 in a memory type dimmer device 11, and an analog signal indicating a dimming level from each fader F1-Fn is converted into a digital signal in 256 stages indicated by an 8-bit, and is lead to a system bus 14. A digital signal indicating a dimming level lead to the bus 14, is stored in a memory 16 by a microprocessor 15. The stored substance is read by the processor 15, and is given to a digital/analog conversion circuit 17, while the 8-bit digital signal is converted into an analog signal indicating voltage level in the range of 0-10V. The analog signal thus converted, is given to a signal interface circuit 12, and is separated by every dimmer 3-6, and is lead out as a continued signal through dimming signal limes l3-l6.

Description

[Detailed description of the invention] Industrial applications TECHNICAL FIELD The present invention relates to a device for controlling the lighting of a stage or the like.

BACKGROUND OF THE INVENTION The electrical configuration of a conventional dimmer device is shown in FIG. and the sex wires N, respectively. The neutral wire N in this star-shaped connection is grounded. Lighting loads 56 to 59 are connected to each of the dimmers 52 to 55, respectively. Each of the dimmers 52 to 55 is controlled from a signal interface 61 included in the memory type dimmer 60 via dimming signal lines 152 to N55.

The memory type dimming control device 60 includes a plurality of faders F51 to
An analog/digital conversion circuit (hereinafter referred to as r) for converting the dimming level set by P5n into a digital signal
An A/D conversion circuit (sometimes abbreviated as "A/D conversion circuit") 62 is provided. The digital signal derived from analog/digital conversion circuit 62 is stored in memory 64 by microprocessor 63. Memory 6 representing dimming level
The stored contents of No. 4 are sequentially read out by the microprocessor 63 and converted into an analog signal representing the dimming level by a digital/analog conversion circuit (hereinafter sometimes abbreviated as "rD/A conversion circuit") 65. , is provided from the signal interface 61 to each of the dimmers 52 to 55. The memory type light control device 60 is provided with a display means b6 and a keyboard 67, which are used by the operator to perform operations such as light control and health settings.

Problem to be Solved by the Invention In the conventional dimming control device, the three-phase AC power supply 51
On the other hand, when there is a difference in the current flowing through each phase R, S, and T of the 63-phase AC power supply 51, which is a single-phase load, the dimmers 52 to 55 respond to a drop in the voltage of each phase R, S, and T. There are also differences, and each phase R
, S, and T change. When the power supply voltage changes, the power supplied to the lighting loads 56 to 59 whose phase is controlled by the dimmers 52 to 55 at phase angles corresponding to the dimming level changes, and the brightness changes. That is, there is a problem in that the actual dimming levels of the lighting loads 56 to 59 change due to voltage changes in each phase.

The load capacity of the lighting loads 56 to 5 for dimming control in stages, halls, and banquet halls is considerably larger than the capacity of the lighting loads of general residential lighting, office lighting, and the like. For example, a typical household lighting fixture includes two 40W fluorescent lamps with a total capacity of 8QWn. stage, hall,
The lighting load capacity in a banquet hall reaches 1200W even in a relatively small-scale venue. Furthermore, in addition to the completely different capacity of the lighting equipment used, the difference is that the area of the lighting load or the object to be irradiated is very large.Due to the large capacity of the lighting load, three-phase power supplies AC is often used. The lighting load is distributed to each phase of the three-phase alternating current so that the load capacity is balanced. This is because if a single-phase AC power source is used and a large capacity lighting load is turned on, a voltage drop will occur if the capacity of the power transformer is not large enough. This influence extends to general equipment other than the stage, such as sound, air conditioning, and power. Therefore, it is necessary to distribute and connect the lighting load to each phase of the three-phase alternating current, and to minimize the difference in load capacity between the phases.

Even if the phase balance of the load capacity is considered in this way and 56 to 5 lighting loads are distributed to each phase R, S, and T, the balance will collapse due to factors other than the 56 to 5 lighting loads. For example, starting a power load causes a temporary voltage drop. In addition, in the process of dimming control of the lighting loads 56 to 59, only the dimming level of a specific phase may become high and power consumption may increase. Furthermore, each phase R, ST to be supplied
It is also possible that the voltage varies. These factors cause the phase balance of the three-phase AC power supply 51 to collapse.

It is assumed that a three-phase AC power source 51 whose phase balance has collapsed performs dimming control of the lighting loads 56 to 59 to produce lighting effects. A signal representing the dimming level is transmitted to the dimmer 52 so that the plurality of lighting loads 56 to 5 are lit at the same brightness.
Give to ~55. However, the brightness actually output to a space for production such as a stage or banquet hall is
It changes for each phase R, S, and T of 1. In particular, the influence becomes large when trying to output light of the same color using the lighting loads 56 to 59 of the same capacity.

For example, to create the effect of a sunset, a stage lighting device called a horizontal light equipped with a red filter is used to uniformly dye the entire stage red. If the phase balance collapses in such a case, the presentation effect of the lighting will be greatly impaired.

In this way, by using the three-phase AC power supply 51,
It is possible to avoid the negative effects on the power load and the like. On the contrary, the phase balance is disrupted due to the influence of the load and the influence of the illumination loads of other phases, and the effect of lighting production by pre-programmed dimming control for each scene is greatly reduced. Conventional dimming control devices have such problems.

An object of the present invention is to provide a dimming control device that does not cause variations in the brightness of the lighting load even if the voltage balance of each phase is disrupted when a multiphase AC power source is used as a power source for the lighting load.

Means for Solving the Problems The present invention provides: a multiphase AC power supply; a lighting load connected to one phase of the multiphase AC power supply; means for detecting the voltage of the phase to which the lighting load is connected; and means for correcting the dimming level of the lighting load to compensate for variations in the voltage of the phase to which the lighting load is connected in response to the output from the means.

Operation According to the invention, a lighting load is connected to one phase of a multiphase AC power supply. The dimming level of the lighting load is corrected to compensate for variations in the voltage of the phase to which the lighting load is connected. Therefore, even if the voltage balance between the phases of the multiphase AC power supply is disrupted, variations in brightness of the lighting load will not occur.

Embodiment FIG. 1 is a block diagram showing the configuration of a dimming control device 1 according to an embodiment of the present invention. Each phase R, S, T of 3-phase AC power supply 2
One end of the plurality of dimmers 3 to 6 is connected to the dimmer, and the other end is commonly connected to the neutral wire N. This star-connected neutral wire N is grounded. Each dimmer 3-6 has a lighting load of 7
~lO are connected to each other. Of these, dimmer 3 and 6 are connected to phase R, dimmers are connected to phase S, and dimmer 4 is connected to phase T. That is, two dimmers 3 and 6 are connected to phase R, and only one dimmer 4 and 5 are connected to phase ST. Assuming that each lighting load 7 to 10 has the same capacity, the load capacity for phase R is larger than the load capacity for phases S and T, and the load capacity for phase R is larger than the load capacity for phases S and T.
voltage drop is likely to occur.

Each of the dimmers 3 to 6 is provided with a signal representing a dimming level from the signal interface circuit 12 of the memory type dimming device 11 via dimming signal lines 13 to 16.

The signal representing this dimming level is applied to the lighting load 7 to 1 in the range of 0 to 100% depending on the voltage level in the range of 0 to 10V.
This is a signal for controlling the phase of 0.

Each dimmer 3-6 responds to a signal representing a given dimming level to phase M# the current supplied to the lighting loads 7-10 from each phase R, S, T.

Each dimmer 3-6 is provided with a sawtooth wave generating circuit, a comparator circuit, and a bidirectional three-terminal thyristor. The sawtooth wave generation circuit generates a sawtooth wave synchronized with the power supply voltage waveform of each phase R and S. This sawtooth wave rises near the zero-crossing point of the power supply voltage and falls linearly to the next zero-crossing point. The comparison circuit is LINE! Compare the signal representing the dimming level via 3 to 16 with the sawtooth wave,
Only during the period when the level of the sawtooth wave is below the level of the signal representing the dimming level, the bidirectional three-terminal thyristor is made conductive to supply current to the lighting loads 7 to 10. In this way, phase control is performed in synchronization with the power supply frequency of 50 Hz or 60 Hz.

Faders F1 to Fn are provided to set the dimming levels of the lighting loads 7 to 10. A fader is a type of sliding variable resistor that has operating parts such as knobs. The faders F1 to Fn are set to be able to control one or more lighting loads 7 to 10, respectively.

Normally, when the knobs of the faders F1 to Fn are pulled toward the operator, the dimming level of the corresponding lighting loads 7 to 10 is lowered, and the brightness becomes darker.

Conversely, if you operate the knob in the direction away from the operator,
The dimming level of the corresponding lighting loads 7 to 10 becomes higher and brighter. The faders F1 to Fn are arranged so that the knobs can be operated back and forth in this manner. The positions of the knobs of the faders F1 to Fn correspond to the brightness expressed by the dimming level of the lighting loads 7 to 10. This fader F
The knobs 1 to Fn are fixed to movable contacts that slide linearly across the variable resistor. In this way, fader F
Signals representing the dimming levels of the lighting loads 7 to 1o are derived from 1 to Fn.

The signals from each fader F1 to Fn are transmitted to the memory type dimmer 1.
The signal is converted into a digital signal by an analog/digital conversion circuit 13 provided in 1.

The analog/digital conversion circuit 13 includes faders F1 to F
The analog signal representing the dimming level from n is converted into a digital signal with 256 levels expressed in 8 bits, and is output to the system bus 14. A digital signal representative of the dimming level derived on the system bus 14 is transmitted to the microprocessor 1.
5, it is stored in the memory 16. The stored contents of memory 16 are read by microprocessor 15 and stored in digital 1. / is given to the analog conversion circuit 17.

Digital/analog conversion circuit 17 converts the 8-bit digital signal into an analog signal representing a voltage level in the range of 0 to IOV. This converted analog signal is given to the signal interface circuit 12, separated for each dimmer 3 to 6, and sent as a continuous signal to the dimming signal lines 13 to p.
6.

Generally, the dimmers 3 to 6 are installed at a position away from the memory type dimmer 11. Therefore, the dimming signal lines 13 to β6 for transmitting signals representing the dimming level are relatively long, and generally have to be about 100 m. The signal representing the dimming level derived from the digital/analog conversion circuit 17 is not suitable for such long-distance transmission. Therefore, in order to convert the signal to be suitable for transmission,
A signal interface circuit 12 is provided.

In the signal interface circuit 12, long-distance transmission measures are taken such as matching the line impedance of the transmission line. In addition, the potential of the common return line of the signal is adjusted to dimmers 3 to 6.
The side and the memory type dimmer 11@ are compared, and the difference is used to compensate the signal representing the dimming level input to the dimmers 3 to 6.

For operation of the memory type light control device 11, a display means 18 and a keyboard are provided.

The display means 18 is realized by a liquid crystal display, a cathode ray tube (CRT) display, a plasma display, or the like, and displays various information set by the microprocessor 15. The keyboard 19 is used to input information to the memory type light control device 11 . Further, various switches are provided for instructing the memory type light control device 11 to operate, such as a scene playback switch used for instructing playback of a scene stored in advance. Here, a scene refers to a combination of dimming levels that are set for each lighting load 7 to 10 and treated as one scene in order to enliven the atmosphere of a stage or a banquet hall. The memory 16 stores the dimming levels of the lighting loads 7 to 10 set by the faders F1 to Fn for each scene. The memory 16 also stores programs that describe the operations of the microprocessor 15.

The three-phase AC power supply 2 includes three single-phase AC power supplies 2R, 2S, and 2T whose ends are commonly connected to the neutral wire N in a star-shaped connection.
It consists of Ground voltage Er, Es of each phase R, S, T
, Et are detected by potential transformers PTr, PTs, PTt. The detected ground voltage is converted into a signal representing an effective value by an effective value conversion circuit 20 provided in the memory type light control device 11. Each phase R converted to effective value
The signal representing the voltage to ground of 3.T is converted into a digital signal by the detection interface circuit 21 and guided to the system bus 14. The microprocessor 15 controls the memory 16 by a signal from the detection interface circuit 21.
The signal representing the dimming level, which is the stored content of
, T is corrected to compensate for variations in the ground voltage of T, and then provided to the digital/analog conversion circuit 17. For this reason, the memory 16 also stores information indicating whether each of the lighting loads 7 to 10 is connected to the phases R, S, and T, and according to this information, the second The figure is a flowchart for explaining the operation of correcting the dimming level. From step s1 to step s2, each phase R
, S, and T are read from the detection interface circuit 21 and stored in the memory 16. Next step s3
Then, the voltage of the R phase is compared with 100V. When the R-phase ground voltage is greater than or less than 100V,
The process moves to step s4. The voltage to ground is generally 95 to 105V
In step s4, the signal representing the dimming level of the lighting load 7.10 connected to the R phase is corrected. The original signal stored for each scene in the memory 16 is multiplied by 100 and further divided by the R-phase ground voltage. When step s4 is completed, or when the R-phase ground voltage is equal to 100V in step s3, the process moves to step s5. In step s5, the T-phase ground voltage is compared with 100V. 10
When the voltage is larger than 0V but smaller, the original signal is corrected in step s6 as in step s4. Next, in step s7, the S-phase ground voltage is compared with 100V. If it is larger than 100V but smaller, the process moves to step s8, and similarly to step s4,
The original signal is corrected. In this way, the ground voltage of each phase R8 and T phase is corrected, and the process ends in step S9.

Correction of the fluctuation in the ground voltage of each phase R and ST of the three-phase AC power supply 2 as described above is performed in the memory type dimming control device 11.
For example, this is performed every 50 msec.

The microprocessor 15 updates each lighting load 7 every 50 msec.
The dimming levels for .about.10 are programmed to be read from memory 16 and sequentially derived via signal interface circuit 12. Corrections are made as part of this operation. The memory 16 stores dimming levels of lighting loads 7 to 10 for each scene. Temporal information for transitioning from one scene to the next is also stored. The microprocessor 15 reads out the stored contents and adjusts the dimming levels of the lighting loads 7 to IO for each phase R, S,
Dimming control is performed for each scene while compensating for fluctuations in T's ground voltage.

Here, 10 for R phase or other T and S phases? . Assume that the voltage drops. Furthermore, it is assumed that each of the lighting loads 7 to 10 is dimmed and controlled by a 50% dimming bell. If no correction is made for the voltage drop, the brightness of lighting load 7 and lighting load 1O will be about 10% darker than the other lighting loads 8 and 9. In this embodiment, the dimmers 4 and 5 for controlling the phases of the T-phase and S-phase lighting loads 8 and 9, respectively, have 5
A signal representing a dimming level of 0% is provided.

The dimmers 3 and 6 for controlling the phase of the lighting loads 7 and 10 connected to the R phase are given a signal representing a dimming level that compensates for the voltage drop. That is, the calculation result according to the following first formula, 50X100÷90=55.
6. From (1), dimmers 3 and 6 have 55.
6? , δ is provided. As a result, the brightness of lighting loads 7 and 10 is reduced by lighting load 8.
And the appearance remains unchanged. Therefore, the brightness irradiated onto the stage or the like from the lighting loads 7 to 10 becomes a --like smooth brightness.

FIG. 3 is a flowchart for explaining the operation of inputting information indicating which phases R, S, and T of the three-phase AC power supply 2 the lighting loads 7 to 10 are connected to. step r
From step 1 to step r2, manual key processing from the keyboard 19 is performed. Next, in step r3,
A determination is made regarding the key entered. If the key force is not applied, the process returns to step r2 and the same operation is repeated until the key force is applied. If there is key power in step r3, the process moves to step r4, and the number of dimmers 3 to 6 specified is identified by the number. Next, the process moves to step r5, and the input dimmer 3~
A number representing 6 is assigned to variable i. Next step r6
Then, it is identified which phase of the three-phase AC power supply 2, R, T, or S, is designated. Next step】-7
Then, one of unidentified R, T, and S is assigned to variable J. Next, the process moves to step r8, and the contents of variable j are assigned to the first element of the array variable representing the dimmer power supply.

Next, the process returns to step r2 again, and the next key manual process is performed. When it is determined in step r3 that the end key has been input to end the manual key processing, the process moves to step r9 and ends. Each variable i, j and an array variable representing the dimmer power supply is stored in a specific memory location on memory 16.

By having the above-described configuration, this embodiment allows the lighting loads 7 to 7 connected to each phase R, S, and T to be maintained even when the phase balance of each phase R, S, and T is disrupted. There is no variation in brightness of 10, and the lighting load is 7 to 1.
0 does not reduce the effect of dimming control. Moreover, in order to detect the ground voltage, potential transformers P T r , P
It is only necessary to provide T s , P T t , the effective value conversion circuit 20 and the detection interface circuit 21 in the memory type light control device 11 similar to the conventional memory type light control device 60 . There is no need to make any modifications to each dimmer 3 to 6,
Interphase balance can be easily corrected.

In the above embodiments, a three-phase AC power source is used as the multiphase AC power source, but it goes without saying that a power source having more phases may be used.

Further, although the explanation is given for the case where the ground voltage of each phase R, S, and T is 100V, it goes without saying that other voltages may be used.

Furthermore, in order to compensate for fluctuations in the ground voltage, it is divided by the detected ground voltage so that it is inversely proportional to the ground voltage, but it may also be corrected to be inversely proportional to the square of the ground voltage. Of course. Since the brightness of the lighting loads 7 to 10 is considered to correspond to the supplied power, more accurate correction can be performed. However, it is relatively easy to keep the variation in the ground voltage between each phase within about 10%, so as in this embodiment, sufficient compensation can be achieved by making the correction inversely proportional to the ground voltage. Calculation processing for correction becomes easier.

Furthermore, the dimmers 3 to 6 and the lighting loads 7 to 10 are
Although it is connected in a star shape to the 3-phase AC power supply 2,
Of course, the wires may be connected in a triangular manner. In this case, it is sufficient to detect the line voltage and compensate for the fluctuations in the same way as in the above-described embodiment.Advantages of the Invention As described above, according to the present invention, the voltage of the phase to which the lighting load is connected fluctuates. However, the dimming level of the lighting load is corrected to compensate for the fluctuation, so there is no change in the brightness of the lighting load. , there will be no variation in the brightness of the lighting load.

Further, according to the present invention, when a plurality of lighting loads are not connected to each phase of a multiphase AC power supply, each lighting load can be freely controlled without considering the influence on or from other lighting loads. It is possible to perform lighting effects by controlling the light of the load.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the electrical configuration of an embodiment of the present invention, Fig. 2 is a flowchart for explaining the operation of compensating for fluctuations in ground voltage. FIG. 4 is a block diagram showing the configuration of a conventional dimming control device. 1.Dimmer control device, 2...3-phase AC power supply, 3-6...
Dimmer, 7 to 10... Lighting load, 11... Memory type dimmer, I2/signal interface circuit, 15... Microprocessor, 16... Memory, one... Keyboard, 20 ...Effective value conversion circuit, 21...Detection interface circuit, PTr, PTs, PTt...Instrument transformer, F1 to Fn...Fader agent Patent attorney Number of strokes Keishibu Figure 2

Claims (1)

[Claims] A multi-phase AC power supply, a lighting load connected to one phase of the multi-phase AC power supply, means for detecting the voltage of the phase to which the lighting load is connected, and an output from the detection means. and means for responsively correcting the dimming level of the lighting load to compensate for variations in the voltage of the phase to which the lighting load is connected.