JPS5919430B2 - dimmer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a light control device for controlling the lighting and brightness of an illumination lamp.

BACKGROUND ART In lighting equipment, a series lighting system using constant current control is generally adopted as a system for maintaining a plurality of electric lights at a constant brightness.

FIG. 1 shows a typical example of a conventional dimming system. In FIG. 1, 1 is a power source for lighting, 2 is a control device, 3 to 10 are electric light transformers connected in series, 1
1 to 18 are lighting equipment including electric lights connected to each transformer as shown in the figure. In this system, when all the lights are turned on at a certain brightness, the control device 2 detects the current flowing through the supply line 19 that supplies power to the lights 11 to 18, and this detected current is set at a preset constant level. The control operation is performed to match the target current that can bring about the brightness of the light.
This control device 2 has a current control section, and the current control section is constituted by a group of elements such as an SCR type using a thyristor or a CR type using a resonant circuit consisting of a capacitor and a resistor. No matter which of these element groups is used, the control device 2 itself performs operations from current detection to control using analog signals.
The control circuit is fixed, and disturbances such as noise peculiar to analog signals are likely to occur, making it difficult to control the current value with high precision. In addition, with conventional devices, in order to add additional functions in addition to the original current value control, a new control circuit must be installed. There were disadvantages such as it was difficult to temporarily store values, and furthermore, it was not easy to manage the lighting time of electric lights. In addition, the conventional device is device 1.
Since it is common to have only one control circuit per unit, when used in places where reliability is particularly required,
For example, when used for lighting installed on an airport runway, there are concerns about reliability. Therefore, the present invention provides a digital SCR type light control device using a thyristor that can perform highly accurate and reliable current control and can easily add various additional functions. The purpose is to In order to achieve this object, the present invention provides a light control device that controls the brightness of the electric light by controlling the current supplied to the electric light from an AC power source, in which the current applied to the electric lamp is controlled by controlling the firing angle. a current detection circuit that detects the current value in synchronization with the frequency of the AC power source and converts the detected current value into a digital signal; It has a signal switching circuit that switches the signal at each predetermined cycle, a storage device that stores detected current values and set value information switched at each predetermined cycle switched by the signal switching circuit, and a reciprocal arithmetic processing unit. Each arithmetic processing unit compares the detected current value stored in the storage device with set value information at each predetermined period, calculates a reference firing angle value corresponding to the optimum brightness of the electric lamp, and digitally converts it into a digital value. arithmetic processing in which each of the arithmetic processing units determines whether another arithmetic processing unit is abnormal and outputs a reference firing angle value by another normal arithmetic processing unit in place of the abnormal arithmetic processing unit; and a firing angle command generation circuit that outputs a firing angle command signal for controlling the firing angle of the thyristor at a predetermined timing according to the predetermined period based on the digital signal of the reference firing angle value. It is characterized by having the following.

The present invention will be described below based on illustrated embodiments.

FIG. 2 is a block diagram showing an example of a light control device according to the present invention. The control operation of the light control device is started when the power supply 21 is turned on and the electric lamp group 26 is energized and current flows through the circuit. At this time, that is, at the beginning, the reference firing angle value is sent from the arithmetic processing unit 35 or 36 in the arithmetic processing unit having a plurality of arithmetic processing units to the ignition command generation circuit 30 via the input/output interface 31 or 34. is output. The ignition command generation circuit 30 that receives this holds the reference ignition angle value, and compares this reference value with the power supply phase counter 2.
When the count value of the counter 29 matches the reference firing angle value, a firing command is immediately sent to the thyristor 24. Here, the arithmetic processing unit 3
The reference firing angle value given from 5 or 36 is
This value is intended only for lighting the lamp by passing a current through it, and any value may be used within the range of the firing angle that is below the rated current value of the lamp (but above the minimum lighting current). Now, when the electric lamp group 26 is energized, the current detector 22
The circuit current is detected, and the detected current value is converted into a digital quantity via the A/D converter 27 and sent to the input/output interface 31 or 34 of the complex arithmetic processing section 39.

At this time, since the timing of the A/D converter 27 needs to be synchronized with the processing performed by the complex arithmetic processing unit 39, it depends on the same synchronization signal as the synchronization signal supplied to the arithmetic processing unit 35 or 36. However, these two types of synchronization signals are generated by the same oscillator 28. When the thyristor 24 is fired according to the reference firing angle value, the voltage across both terminals of the thyristor 24 becomes zero during energization (see Section 1 of FIG. 3).

When the voltage at both terminals of the thyristor 24 becomes zero, a current flows through the lamp group 26, and the A/D converter 27 performs 0N-0FF of the current value sampling gate signal as shown in FIG. 3b to perform digital conversion of the current value. While performing the calculation, the result is supplied to the input/output interface 31 or 34 of the complex calculation processing section 39. The arithmetic processing unit 35 or 36 includes a signal switching section 41 consisting of a signal switching circuit that operates in synchronization with the supply of this current value, and an input/output interface 31 or 34.
The digitized current value for half a cycle of the power supply frequency is taken in through the However, two arithmetic processing units 35
, 36 operate to take in the current value for half a cycle alternately. In other words, when the power supply voltage is on the positive side, thyristor 2
When the thyristor 4 is fired, the current value is taken in by the processing unit 36, while when the thyristor 24 is fired at a negative time point, the current value is taken in by the processing unit 35...
This is done alternately. Therefore, depending on the contents of the control counter in the storage unit 40 having a storage device, a control counter, etc., the arithmetic processing units 35 and 36 may be prohibited from starting current value sampling. The signal switching section 41 transfers the current value signal detected by the current detection section 22 and converted into a digital quantity by the A/D converter 27 to the two input/output interfaces 31 and 34 in consideration of the polarity of the power supply voltage. This is a switching circuit that operates to supply either one. When the power supply voltage shifts from the negative side to the positive side and crosses the zero point, a pulse is output from the zero detection circuit 42, and this pulse causes the signal switching unit 41 to send the current value signal to the input/output interface 34. It operates to supply. Next, when the power supply voltage moves from the positive side to the negative side and crosses the zero point, the zero detection circuit 42 outputs a pulse again and supplies it to the signal switching section 41. In response to this, the signal switching section 41
operates to supply a current value signal to the input/output interface 31. Thereafter, these series of operations are repeated. Therefore, each time the power supply voltage crosses zero, that is, each time a positive/negative cycle is repeated, the signal switching unit 41 changes the current value signal to the input/output interface 34→31→3.
Flip-flop-like switching operations are performed alternately in the order of 4→31, and so on. If section 1 in FIG. 3 is the beginning of control, the sampled current value is
1, the input/output interface 34, and the arithmetic processing unit 36.

At this point, the contents of the control counter in the storage unit 40 are initially "
If it is set to 0, it remains at 601.
When the current value input starts, the arithmetic processing unit 36 reads the contents of the control counter in the storage unit 40, determines whether the contents of the control counter are "0" or an even number, and if it is an even number, samples the current value from now on. It is accepted and sequentially stored in a storage device within the storage unit 40. At this point, the content of the control counter is 01, so the current sample values are stored sequentially, and when the input of the current sample values is completed, the arithmetic processing unit 36 increments the value of the control counter in the storage unit 40 by "11". The control counter value in the storage section 40 changes from "O" to "1". On the other hand, during the operation of the current sample in the interval 1VC}, the power supply voltage crosses the zero point from the positive side to the negative side, so that the signal switching unit 41 transfers the current sample value through the input/output interface 31. It operates to supply the data to the arithmetic unit 35. Next, in the section, the thyristor 24
At the initial point in time when the current sample value is supplied to the arithmetic processing unit 35 via the signal switching unit 41 and the input/output interface 31, the arithmetic processing unit 35 stores the memory unit 40.
Read the contents of the control counter in the control counter and determine whether the contents of the control counter are an odd number. If the number is odd, interval 1
The current sample value is stored in the storage device in the storage unit 40 in the same way as in the case of , and the series of current sample value input is completed. It changes from 1" to 62".The initial firing of the section 1 (the beginning of control) and the section is performed using the reference firing angle value as described above.By the way,
In section 1, the arithmetic processing unit 36 compares the measured current value with setting value information (for example, control target current value, etc.) preset in the storage device in the storage unit 40 when sampling is completed, and determines the actual current value. The optimal firing angle for the next section (section) is determined by calculation in order to match the target current value, and the optimal firing angle is determined after confirming that the firing command for the section has already been generated from the firing command generation circuit 30. The reference firing angle value is sent to the input/output interface 31 to the firing command generation circuit 30.
Output via.

On the other hand, in the section, the arithmetic processing unit 36 that has finished storing the current sample value performs the same operation as in section 1, and finally the optimum firing angle for the section is calculated and the firing command generation circuit Set to 30. The ignition command generating circuit 30 that receives this command issues a thyristor ignition command at the optimum timing. By repeating the procedure described above, the arithmetic processing unit 36 controls the firing angle when the power supply voltage is on the positive side for each cycle of the power supply frequency, while the arithmetic processing unit 35 controls the firing angle when the power supply voltage is on the negative side. The arc angle can be controlled every cycle of the power supply frequency, and if these two operations are considered together, the firing of the thyristor will be fed back to the optimum state every half cycle of the power supply frequency, that is, every time.

An example of the processing in the arithmetic processing units 35 and 36 from the current value sampling time 0 to the "optimal firing angle output" in the above processing is shown in a flowchart in FIG. The series of operations described so far are for the case where both the arithmetic processing units 35 and 36 are normal.
The operation when the is abnormal will be explained.

Now, suppose that the arithmetic processing unit 35 stops functioning for some reason in the section shown in FIG. At the time when the control counter value is read and a determination is made as to whether it is 0 or an even number, the content of the control counter value is 61, so it is determined that the control counter reading is not normal, and the processing is as shown in Figure 4. Branched to connector 4 in the flowchart. FIG. 5 shows an example of the processing of the arithmetic processing unit 36 after branching to step 4.

- When the arithmetic processing unit 36 determines that the control counter value is abnormal, the arithmetic processing unit 36 recognizes that the arithmetic processing unit 35 is abnormal, and sends an instruction via the input/output interface 34 to stop all processing of the arithmetic processing unit 35. A stop command is output to the processing stop command circuit 32. Upon receiving this, the arithmetic processing unit 35 stops all processing, and at the same time, the arithmetic processing unit 36 outputs alarm death and failure information to the alarm display section 38 via the input/output interface 34. Thereafter, the arithmetic processing unit 36 performs a current value sampling operation similar to that during normal operation, and performs feedback control every cycle of the power supply frequency. In this case, since the arithmetic processing unit 35 is removed from the control system, optimal firing angle control is performed for the firing command on the positive side of the power supply voltage, but the firing command on the negative side is the same as the firing command on the positive side. Since this is an ignition command, thyristor ignition control is performed every cycle. In this case, the control accuracy will be lower than when both the arithmetic and control units 35 and 36 are normal, but the light will not go out and the dimming control will continue, so the control will be performed without any problems in practice. , highly reliable control becomes possible.
The above-mentioned operation is the same even when the arithmetic processing unit 36 becomes abnormal and the processing unit 35 is normal. In this way, the series of processes according to the present invention includes the process of sampling the current value via the A/D converter 27 and the process of sending the reference firing angle value to the firing command generation circuit 31 using various signals such as 0N-0FF.
It is treated as a digital signal based on the binary state of ``.

Therefore, it is suitable to use computers as the processing units 35 and 36, which can further increase the variety of processing. In the above embodiment, the composite processing calculation unit 3
Although an example of the control operation in the case where the computer 9 is constituted by two arithmetic processing units 35 and 36 has been shown, it goes without saying that the present invention can be applied even if there are three or more arithmetic processing units.

Next, FIG. 6 shows a modification of the present invention.

According to this, by adding the external input/output signal switching section 43, the external input device 44, and the external output display device 45, a multifunctional lighting control device can be obtained. That is, the external input/output signal switching unit 43 connects both the external input device 44 and the external output display device 45 to the input/output interface 3.
This is a switching circuit for connecting to either one of 1 or 34. Now, the switching unit 43 connects the interface 31, external input device 44, and external output display device 45.
Assume that the device is configured to connect. If it is desired to change the brightness while the lamp is turned on using such a lamp control device, the target current value referred to in the flowchart (FIG. 4) may be changed. First, when information regarding target current value change is input from the external human power device 44, the input change information is transferred to the input/output interface 31.
In response, the arithmetic processing unit 35 stores information regarding the target current value in the storage unit 40.
to be stored in memory. Thereafter, the information regarding the newly held target current value will be referenced by both the arithmetic processing units 35 and 36 in the above-described processing procedure for controlling the firing angle, and thus the brightness of the lamp will change. I will do it. The method of inputting the necessary information from the external input device 44 may be a manual method or a method of directly inputting the output of some other device to the external input device 44 as it is. In addition, if you want to change the brightness of the lights, blinking state, etc. over time according to a certain rule, you can input this series of information to the external input device 44.
The information is input to the storage unit 40 in advance, and the arithmetic processing unit 35
, 36 starts the thyristor in order to control the brightness and blinking state of the light over time by counting the synchronization signals output from the oscillator 28 and explaining and recognizing a series of information given in advance. It is also possible to control the angle.

Further, if it is desired to adjust the brightness of the electric light according to the brightness of the surrounding environment in which the electric light is placed, the relationship between the brightness of the environment and the brightness of the electric light is stored in advance in the storage unit 40, and the external input device 44 The brightness of the surrounding environment is input through the computer, and the processing units 35 and 36 refer to this input information and information stored in advance in the storage unit 40 representing the relationship between the brightness of the environment and the brightness of electric lights. The firing angle of the thyristor can be controlled by this.

As explained above, according to the present invention, the current flowing through the lamp is detected by the current detection circuit in synchronization with the power supply frequency and converted into a digital signal, and this digital signal is switched at predetermined intervals by the signal switching circuit. The setting value information is stored in a storage device in advance, and based on the information stored in this storage device, each arithmetic processing unit in the arithmetic processing unit determines a reference point corresponding to the optimal brightness of the light at a predetermined period. Calculate arc angle values and output them sequentially as digital signals,
This output is converted into a firing angle command signal by the firing angle command generation circuit and given to the thyristor at a predetermined timing to control the firing angle of the thyristor. Therefore, the firing of the thyristor is performed at the optimum timing at each predetermined period. Therefore, the current flowing to the lamp can be controlled with high precision without causing disturbances such as noise. In addition, each processing unit in the processing unit is configured to determine whether another processing unit is abnormal and output a reference firing angle value using another normal processing unit in place of the abnormal processing unit. Therefore, even if one processing unit in the processing unit malfunctions and stops functioning, other normal processing units will work to supplement this function, so the lights will not go out and the lights will not go out. Light control is performed continuously, and highly reliable current control can be performed. Further, according to the present invention, since a digital system is adopted, various additional functions can be easily added. For example, by adding one or both of an external input device that inputs external data and an external output display device that outputs internal information, it is possible to transfer and receive information inside and outside the device. If one of the arithmetic processing units is abnormal, a processing stop command circuit is added to stop the operation of the abnormal arithmetic processing unit, or a signal based on a failure that occurs in the equipment itself, or a signal generated in peripheral connected equipment is added. Efficient and multifunctional control can be easily performed by adding an alarm display device that temporarily suspends control operations or outputs alarm signals based on signals input to the processing unit or signals input to the processing unit. .

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a representative example of a conventional dimming system, Fig. 2 is a block diagram showing the configuration of a dimming device according to the present invention, and Fig. 3 is a voltage across the thyristor that is affected by normal control by the control device. and a timing chart of current value sampling, FIG. 4 is a flowchart showing an overview of arithmetic processing, FIG. 5 is a flowchart when an abnormality occurs in the arithmetic processing device, and FIG. 6 shows another embodiment of the present invention. FIG. DESCRIPTION OF SYMBOLS 1... Power supply, 2... Light control device, 3-10... Electric light transformer, 11-18... Lighting equipment, 21... Power supply device, 22... Current detector, 23 ... Thyristor both ends voltage detector, 24... Thyristor, 26... Electric lamp group, 2r... A/D converter, 28... Oscillator, 29
... Power supply phase counter, 30... Firing command generation circuit, 31, 34... Input/output interface, 32, 3
3... Processing stop command circuit, 35, 36... Arithmetic processing device, 38... Alarm generation display device, 39... Complex processing computing section, 40... Storage section, 41... Signal switching Department,
42... Zero detection circuit, 43... External input/output signal switching section. 44... External input device, 45... External output display device.

Claims (1)

[Claims] 1. A light control device that controls the brightness of a light by controlling the current supplied to the light from an AC power supply, comprising: a thyristor that controls the current flowing to the light by controlling the firing angle;
a current detection circuit that detects the energizing current value in synchronization with the frequency of the AC power source and converts the detected current value into a digital signal; Each of these arithmetic processing units has a signal switching circuit that switches each time, a storage device that stores detected current values and set value information that are switched every predetermined period by this signal switching circuit, and a plurality of arithmetic processing units. The detected current value stored in the storage device and the set value information are compared at each predetermined cycle, and a reference firing angle value corresponding to the optimum brightness of the lamp is calculated and sequentially outputted as a digital signal. In addition, each arithmetic processing unit includes an arithmetic processing unit that determines an abnormality in another arithmetic processing unit and outputs a reference firing angle value by another normal arithmetic processing unit in place of the abnormal arithmetic processing unit; and a firing angle command generation circuit that outputs a firing angle command signal for controlling the firing angle of the thyristor at a predetermined timing according to the predetermined cycle based on the digital signal of the firing angle value. A light control device featuring: