JP2020107554A - Lighting control device and lighting device - Google Patents

Abstract

To provide a lighting control device and a lighting device capable of suppressing a difference between a target value of a ratio of light emission amounts of a plurality of light sources and an actual light emission state while suppressing output power.SOLUTION: A lighting control device according to the present invention includes a plurality of lighting circuits that respectively light a plurality of light sources, and a control device that receives a plurality of dimming command values respectively corresponding to the plurality of light sources from the outside and controls the plurality of lighting circuits, and when the sum of the output powers of the plurality of lighting circuits according to the plurality of dimming command values exceeds a preset value, the control device lowers each of the plurality of dimming command values such that the sum of the output powers is equal to or less than the set value.SELECTED DRAWING: Figure 1

Description

The present invention relates to a lighting control device and a lighting device.

Patent Document 1 discloses a power supply circuit including two lighting units and a control unit. The lighting unit generates a first current for lighting the first light source unit and a second current for lighting the second light source unit. The control unit controls the lighting unit based on a first control signal that controls the light amount of the light generated from the first light source unit and a second control signal that controls the light amount of the light generated from the second light source unit. The control unit sets the output value of the first current based on the first control signal. In addition, the control unit regulates the second output value such that the total value of the output value of the first current and the output value of the second current is equal to or less than the output rated value. Therefore, it is possible to suppress output of an excessive amount of current from the power supply circuit.

JP, 2018-170095, A

In the power supply device of Patent Document 1, the light emission amount of the second light source unit is limited according to the light emission amount of the first light source unit. For this reason, the color temperature obtained by mixing the light emitted from the two light source units may be different from the color temperature designated from the outside.

The present invention has been made to solve the above problems, and a lighting control device that can suppress the difference between the target value of the ratio of the light emission amounts of the plurality of light sources and the actual light emission state while suppressing the output power. And to obtain a lighting device.

A lighting control device according to the present invention receives a plurality of lighting circuits for respectively lighting a plurality of light sources and a plurality of dimming command values respectively corresponding to the plurality of light sources from the outside, and controls the plurality of lighting circuits. A control device, the control device, when the sum of the output power of the plurality of lighting circuits according to the plurality of dimming command values exceeds a set value that is a predetermined value, Each of the plurality of dimming command values is lowered so that the sum is equal to or less than the set value.

In the lighting control device according to the present invention, the control device lowers each of the plurality of dimming command values so that the sum of the output powers of the plurality of lighting circuits is equal to or less than the set value. Therefore, it is possible to suppress the difference between the target value of the ratio of the light emission amounts of the plurality of light sources and the actual light emission state while suppressing the output power of the lighting control device.

3 is a circuit block diagram of the lighting device according to Embodiment 1. FIG. 5 is a flowchart illustrating an operation of the first control unit according to the first embodiment. It is a figure which shows the relationship between color temperature and output electric power in a comparative example. FIG. 4 is a diagram showing a relationship between color temperature and output power in the first embodiment. 9 is a flowchart illustrating an operation of the first control unit according to the fourth modification of the first embodiment. FIG. 7 is a diagram showing a relationship between color temperature and output power in the modification of the first embodiment. FIG. 6 is a circuit block diagram of the lighting device according to the second embodiment. FIG. 9 is a circuit block diagram of an illumination device according to a third embodiment. It is a circuit block diagram of the illuminating device which concerns on Embodiment 4. It is a figure which shows an example of the relationship between the DUTY ratio of a dimming signal and a dimming rate. It is a figure which shows an example of the relationship of the period of a light control signal and a light control rate.

A lighting control device and a lighting device according to an embodiment of the present invention will be described with reference to the drawings. The same or corresponding components are denoted by the same reference numerals, and repeated description may be omitted.

Embodiment 1.
FIG. 1 is a circuit block diagram of a lighting device 100 according to the first embodiment. The lighting device 100 includes a lighting control device 1, a first light source unit 11-1, a second light source unit 11-2, and a control unit 12. The lighting control device 1 is supplied with electric power from the commercial power supply AC and turns on the first light source unit 11-1 and the second light source unit 11-2. The lighting control device 1 supplies the first light source unit 11-1 and the second light source unit 11-2 with electric power that is dimmed or toned.

The commercial power supply AC is an AC power supply. The lighting control device 1 may be connected to a DC power supply. When a direct current power supply is connected to the lighting control device 1, the rectifying circuit 13, the inrush current suppressing circuit 14, and the PFC (Power Factor Correction) circuit 15 described later are unnecessary.

The first light source unit 11-1 is connected to the output side of the lighting control device 1 via a terminal unit CN1. The second light source unit 11-2 is connected to the output side of the lighting control device 1 via the terminal unit CN2. The first light source unit 11-1 and the second light source unit 11-2 have a plurality of light sources connected in series. The light source is a light emitting element such as an LED. A plurality of light sources may be connected in parallel or in series parallel. Moreover, each of the first light source unit 11-1 and the second light source unit 11-2 may have one or more light sources.

The first light source unit 11-1 includes an LED that emits light having a color temperature of 5000K, for example. The second light source unit 11-2 includes an LED that emits light having a color temperature different from that of the first light source unit. The color temperature of the second light source unit 11-2 is, for example, 3000K.

Further, the lighting control device 1 is connected to a control unit 12 via a terminal portion CN3. The control unit 12 inputs a plurality of dimming command values to the lighting control device 1. The control unit 12 is, for example, a dimming controller.

The lighting control device 1 includes a rectifying circuit 13, an inrush current suppressing circuit 14, a PFC circuit 15, a first lighting circuit 21, a second lighting circuit 22, a first control unit IC1 and a second control unit IC2. The rectifier circuit 13 rectifies the AC voltage and converts it into a pulsating voltage. The rectifier circuit 13 includes a full-wave rectifier circuit including, for example, a diode bridge. The rectifier circuit 13 also includes an input filter circuit. The input filter circuit is, for example, a noise filter circuit.

The inrush current suppressing circuit 14 is connected to the output of the rectifying circuit 13. The inrush current suppressing circuit 14 suppresses the inrush current that suddenly flows into the capacitor connected in parallel with the PFC circuit 15 at the subsequent stage when the commercial power supply AC is turned on.

The PFC circuit 15 is a power factor correction circuit. The PFC circuit 15 is connected to the output of the inrush current suppression circuit 14. The PFC circuit 15 converts the pulsating current voltage output from the inrush current suppressing circuit 14 into a DC voltage and outputs the DC voltage. The PFC circuit 15 is, for example, a boost chopper circuit. The PFC circuit is composed of a coil, a switching element and a diode (not shown).

The input of the first lighting circuit 21 and the input of the second lighting circuit 22 are connected in parallel to the output of the PFC circuit 15. The PFC circuit 15 is a common power supply circuit that supplies electric power to the first lighting circuit 21 and the second lighting circuit 22.

The first lighting circuit 21 supplies electric power to the first light source unit 11-1. The first lighting circuit 21 is, for example, a buck converter circuit. The first lighting circuit 21 includes a switching element Q1, a diode D1, a coil L1, a capacitor C1 and a resistor R1.

The second lighting circuit 22 supplies electric power to the second light source unit 11-2. The second lighting circuit 22 is, for example, a buck converter circuit. The second lighting circuit 22 includes a switching element Q2, a diode D2, a coil L2, a capacitor C2, and a resistor R2. The switching elements Q1 and Q2 are, for example, MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors).

The lighting control device 1 includes a control device that controls the first lighting circuit 21 and the second lighting circuit 22. The control device includes a first control unit IC1 and a second control unit IC2. The first control unit IC1 and the second control unit IC2 are, for example, microcomputers. The first controller IC1 controls the first lighting circuit 21. The second control unit IC2 controls the second lighting circuit 22.

In the first lighting circuit 21, the output of the PFC circuit 15 on the high potential side is connected to the drain of the switching element Q1. One end of the coil L1 and the cathode of the diode D1 are connected to the source of the switching element Q1. The gate of the switching element Q1 is connected to the Vg1 terminal of the first controller IC1 via a MOSFET driver (not shown).

The other end of the coil L1 is connected to the positive electrode of the capacitor C1. The terminal P1 of the first controller IC1 and one end of the resistor R1 are connected to the negative electrode of the capacitor C1. The anode of the diode D1 and the other end of the resistor R1 are connected to the circuit reference potential GND which is the output on the low potential side of the PFC circuit 15. The terminal portion CN1 is connected to the capacitor C1. The capacitor C1 is connected to the first light source unit 11-1 via the terminal portion CN1.

Similarly, the drain of the switching element Q2 is connected to the high potential output of the PFC circuit 15. One end of the coil L2 and the cathode of the diode D2 are connected to the source of the switching element Q2. The gate of the switching element Q2 is connected to the Vg2 terminal of the second controller IC2 via a MOSFET driver (not shown).

The other end of the coil L2 is connected to the positive electrode of the capacitor C2. The terminal P2 of the second controller IC2 and one end of the resistor R2 are connected to the negative electrode of the capacitor C2. The anode of the diode D2 and the other end of the resistor R2 are connected to the circuit reference potential GND which is the output on the low potential side of the PFC circuit 15. The terminal portion CN2 is connected to the capacitor C2. The capacitor C2 is connected to the second light source unit 11-2 via the terminal portion CN2.

The first control unit IC1 outputs a switching signal for operating the switching element Q1 from the terminal Vg1 of the first control unit IC1 so that the voltage of the terminal P1 of the first control unit IC1 becomes a predetermined voltage. As a result, a predetermined direct current flows through the first light source unit 11-1. Therefore, the first light source unit 11-1 can be controlled with a constant current. Moreover, when performing the light control of the first light source unit 11-1, the target value of the voltage input to the terminal P1 of the first control unit IC1 is changed. As a result, the current flowing through the first light source unit 11-1 changes.

Similarly, the second control unit IC2 outputs a switching signal for operating the switching element Q2 from the terminal Vg2 of the second control unit IC2 so that the voltage of the terminal P2 of the second control unit IC2 becomes a predetermined voltage. .. As a result, a predetermined direct current flows through the second light source unit 11-2. Therefore, the second light source unit 11-2 can be subjected to constant current control. Further, when the dimming of the second light source unit 11-2 is performed, the target value of the voltage input to the terminal P2 of the second control unit IC2 is changed. As a result, the current flowing through the second light source unit 11-2 changes.

The operating voltages of the first control unit IC1 and the second control unit IC2, which are configured by a microcomputer, are generally insufficient as drive voltages for the switching elements Q1 and Q2. In the lighting control device 1, a switching signal is once input from a terminal Vg1 and a terminal Vg2 to a MOSFET driver (not shown). Stable switching can be performed by outputting a switching signal from the MOSFET driver to the switching elements Q1 and Q2.

Next, the connection between the control unit 12 and the lighting control device 1 will be described. The communication terminal of the control unit 12 is connected in series to the communication terminal of the first control unit IC1 and the communication terminal of the second control unit IC2. The control unit 12 has a reception terminal Rx0 and a transmission terminal Tx0 as communication terminals. The first controller IC1 has a reception terminal Rx1 and a transmission terminal Tx1 as communication terminals. The second controller IC2 has a reception terminal Rx2 and a transmission terminal Tx2 as communication terminals.

The terminal portion CN3 has an external receiving terminal 17 and an external transmitting terminal 18. The external reception terminal 17 is connected to the transmission terminal Tx0 of the control unit 12, and the external transmission terminal 18 is connected to the reception terminal Rx0 of the control unit 12. The transmission terminal Tx0 of the control unit 12 is connected to the reception terminal Rx1 of the first control unit IC1 via the terminal portion CN3. The transmission terminal Tx1 of the first control unit IC1 is connected to the reception terminal Rx2 of the second control unit IC2. The transmission terminal Tx2 of the second control unit IC2 is connected to the reception terminal Rx0 of the control unit 12 via the terminal unit CN3.

A control power supply voltage VDD (not shown) of the lighting control device 1 and a circuit reference potential GND of the first lighting circuit 21 and the second lighting circuit 22 are connected to the control unit 12 via a terminal portion CN3.

Between the control unit 12, the first control unit IC1 and the second control unit IC2 by using the communication terminal of the control unit 12, the communication terminal of the first control unit IC1 and the communication terminal of the second control unit IC2 which are connected in this way. You can communicate with. A wired interface such as UART (Universal Asynchronous Receiver Transmitter) is used for communication.

The signal transmitted from the control unit 12 is received by both the first control unit IC1 and the second control unit IC2. A first dimming command value corresponding to the first light source unit 11-1 and a second dimming command value corresponding to the second light source unit 11-2 are sequentially input to the external reception terminal 17 from the outside. The first control unit IC1 and the second control unit IC2 are connected in series to the external receiving terminal 17. The first control unit IC1 transmits the dimming command value received from the control unit 12 to the second control unit IC2 via the communication terminal. Therefore, each of the first control unit IC1 and the second control unit IC2 receives the first dimming command value and the second dimming command value. Therefore, each control unit can refer to the dimming command value processed by another control unit.

Next, an example of communication signals transmitted and received between the control unit 12 and the lighting control device 1 will be described. The communication signal includes, for example, a code including a start, a type, and a data body. The start is a fixed code such as 0x4. Start indicates the start of communication. Here, 0x means a hexadecimal number.

The type is divided into request and response. The request is a signal indicating which control unit is the operation target. For example, the request 0x1 indicates a dimming command request for the first lighting circuit 21 controlled by the first control unit IC1. Further, the request 0x2 indicates a dimming command request for the second lighting circuit 22 controlled by the second control unit IC2.

The response is a signal that notifies the control unit 12 that the lighting control device 1 has received the transmitted signal. The request reception target adds 0x8 to the received request and transmits it as a response. For example, the first control unit IC1 that has received the request 0x1 transmits 0x9 as a response. The second control unit IC2, which has received the request 0x2, transmits 0xA as a response. The control unit, which has received the request not addressed to its own control unit, transmits the received request as it is without converting it into a response.

The dimming command value is stored in the data body. In the data body, the dimming command value represented by the DUTY ratio of the PWM (Pulse Width Modulation) signal is expressed in hexadecimal. The data size of the dimming command value is, for example, 1 byte. Further, the duty ratio of the PWM signal is expressed as a percentage.

For example, a dimming ratio of 100% for all lights corresponds to a DUTY ratio of 5% for a PWM signal. The data body for instructing the duty ratio of 5% of the PWM signal is 0x05 obtained by hexadecimal conversion of 5. The lower limit dimming rate of 5% corresponds to a duty ratio of 85% of the PWM signal. The data body for instructing the duty ratio of 85% of the PWM signal is 0x55 which is a hexadecimal conversion of 85. A dimming rate of 0% when turned off corresponds to a DUTY ratio of the PWM signal of 100%. The data body for instructing the DUTY ratio 100% of the PWM signal is 0x64 obtained by converting 100 into hexadecimal. In the following, the dimming command value is expressed by the dimming rate.

FIG. 2 is a flowchart illustrating the operation of the first control unit IC1 according to the first embodiment. The operation of the first controller IC1 will be described with reference to FIG. First, the first control unit IC1 receives a communication signal (step S1). The first control unit IC1 refers to the request for the communication signal. Thereby, the first control unit IC1 determines whether the received communication signal is a communication signal addressed to the own control unit (step S2).

When the received communication signal is the communication signal addressed to the own control unit, the first control unit IC1 adds 0x8 to the request to generate a response. Hereinafter, a communication signal whose type is response will be referred to as a response signal. In this way, the first control unit IC1 generates and transmits the response signal (step S3). The first control unit IC1 also stores the received dimming command value addressed to its own control unit (step S4). Here, the information of the control unit that processes the dimming command value may be stored together with the dimming command value.

On the other hand, when the communication signal received in step S2 is not the communication addressed to the own control unit, the first control unit IC1 transmits the received communication signal as it is without data processing (step S5). After step S2 or step S5, the first controller IC1 waits for the next communication signal.

The first control unit IC1 determines whether or not all dimming command values transmitted to each control unit have been received (step S6). Here, there are a plurality of conceivable methods for determining whether or not all the dimming command values have been received. For example, in the case of two control units, the dimming command value transmitted to the first control unit IC1 and the dimming command value transmitted to the second control unit IC2 are sequentially waited for reception, and the second control unit IC2 The step S6 may be performed by using the reception of the dimming command value transmitted to the destination as a trigger.

The control unit 12 sequentially transmits a plurality of dimming command values processed by the plurality of control units. Upon receiving the dimming command value processed by the last control unit, each control unit executes step S6. In this case, when each control unit fails to receive the dimming command value transmitted to any one of the control units, the dimming command value received so far is discarded and the dimming command addressed to the first control unit IC1 is discarded. Wait for the value to be received.

The control unit 12 may randomly transmit a plurality of dimming command values that are respectively processed by the plurality of control units. Each control unit has a plurality of flags respectively corresponding to the plurality of control units. The initial values of the plurality of flags are 0. Each control unit sets a flag for the control unit that has received the corresponding dimming command value. That is, the flag is set to 1. In addition, each control unit executes step S6 when the product of all flags is 1. Each control unit may discard old data and give priority to the latest data when the dimming command value is received redundantly for the control unit with the flag of 1.

When all the dimming command values are received in step S6, the first control unit IC1 proceeds to step S7. When all the dimming command values have not been received in step S6, the second control unit IC2 waits for the next communication signal.

In the present embodiment, the dimming command value corresponds to the dimming rate. In step S7, the first control unit IC1 sums the dimming rates that return to all dimming command values. Here, the sum of the first dimming rate T1 corresponding to the first dimming command value and the second dimming rate T2 corresponding to the second dimming command value is calculated.

Next, the first control unit IC1 compares the total dimming rate with the dimming rate limit S which is a preset setting value (step S8). The dimming rate limit S indicates the upper limit value of the dimming rate of the entire lighting device 100. That is, the dimming rate limit S is an upper limit value of the dimming rate in which the light from the first light source unit 11-1 and the light from the second light source unit 11-2 are combined. In the present embodiment, the dimming rate limit S is 100%. In step S8, it is determined whether the sum of the first dimming rate T1 and the second dimming rate T2 is greater than 100%.

When the sum of the first dimming rate T1 and the second dimming rate T2 exceeds the dimming rate limit, the first control unit IC1 adjusts the sum of the first dimming rate T1 and the second dimming rate T2. A new first dimming rate S1 is calculated so as to match the light rate limit (step S9). Here, the new first dimming rate S1=S×T1/(T1+T2).

The first control unit IC1 rewrites the first dimming rate T1 to a new first dimming rate S1. Further, the first control unit IC1 controls the dimming of the first lighting circuit 21 based on the new first dimming rate S1 (step S10).

On the other hand, when the sum of the first dimming rate T1 and the second dimming rate T2 is less than or equal to the dimming rate limit S in step S8, the first control unit IC1 performs dimming control based on the first dimming rate T1. (Step S10).

Next, the operation of the second controller IC2 will be described. Steps S1 to S8 are the same as the operation of the first controller IC1. The second control unit IC2 receives the communication signal from the first control unit IC1 and not from the control unit 12. If the sum of the first dimming rate T1 and the second dimming rate T2 exceeds the dimming rate limit, the second control unit IC2 adjusts the sum of the first dimming rate T1 and the second dimming rate T2. A new second dimming rate S2 is calculated so as to match the light rate limit (step S9). Here, the new second dimming rate S2=S×T2/(T1+T2).

The second control unit IC2 rewrites the second dimming rate T2 to a new second dimming rate S2. Further, the second control unit IC2 controls the dimming of the second lighting circuit 22 based on the new second dimming rate S2 (step S10). On the other hand, when the sum of the first dimming rate T1 and the second dimming rate T2 is less than or equal to the dimming rate limit S in step S8, the second control unit IC2 performs dimming control based on the second dimming rate T2. (Step S10).

FIG. 3 is a diagram showing the relationship between color temperature and output power in a comparative example. FIG. 4 is a diagram showing the relationship between the color temperature and the output power in the first embodiment. In the comparative example shown in FIG. 3, the lighting device 100 is not provided with a dimming rate limit. In FIGS. 3 and 4, the output powers of the first lighting circuit 21 and the second lighting circuit 22 are changed from 0% to 100%. The color temperature of the first light source unit 11-1 is set to 5000K and the color temperature of the second light source unit 11-2 is set to 3000K.

When the dimming rate limit is not provided, as shown in FIG. 3, when the first lighting circuit 21 and the second lighting circuit 22 are lit at the dimming rate of 100%, the color temperature becomes about 4000K and the output power becomes It will be the maximum. In this way, when the first lighting circuit 21 and the second lighting circuit 22 are controlled based on independent dimming signals, the overall dimming rate of the lighting device exceeds the target value depending on the color temperature. It may happen. Further, it is often not always necessary to set the brightness at which the first lighting circuit 21 and the second lighting circuit 22 are both turned on at a dimming rate of 100%. Furthermore, when the output power is high, there is a risk that the circuits that make up the lighting device 100 will be overloaded.

On the other hand, in the present embodiment, the first dimming rate T1 and the second dimming rate T2 are rewritten to the new first dimming rate S1 and second dimming rate S2 by the above-described arithmetic expression. As a result, the sum of the first dimming rate T1 and the second dimming rate T2 can be made less than or equal to a predetermined value. The dimming rate corresponds to the output power of the lighting circuit. That is, in the present embodiment, the sum of the output powers of the plurality of lighting circuits can be suppressed below the set value. Therefore, it is possible to prevent the maximum output of the lighting control device 1 corresponding to the combined dimming rate from exceeding the preset upper limit value.

As a result, as shown in FIG. 4, the output power of the lighting control device 1 can be suppressed below the set value regardless of the color temperature. Therefore, even when the dimming command value outside the output range is received from the outside, the lighting control device 1 can be protected from an excessive load. Further, generally, it is often required to control so that the total power of the first lighting circuit 21 and the second lighting circuit 22 is constant. Therefore, in the present embodiment, the lighting control device 1 can be appropriately controlled.

Further, in order to limit the output power, it is conceivable to limit the light emission amount of the other light source unit according to the light emission amount of the one light source unit. In this case, the color temperature obtained by mixing the light emitted from the two light source units may be different from the color temperature designated from the outside.

For example, it is assumed that a command to set the light emission amount of the first light source unit to 7 and the light emission amount of the second light source unit to 7 is received from the outside. At this time, since the light emission amounts of the first light source unit and the second light source unit are equal, the color temperature designated from the outside is an intermediate color temperature between the first light source unit and the second light source unit. Here, it is assumed that the upper limit of the total amount of light emitted from the first light source section and the second light source section is 10. When the light emission amount of the second light source unit is set to 3 with reference to the light emission amount 7 of the first light source unit so as to satisfy this upper limit, the ratio of the light emission amounts changes. Therefore, unlike the color temperature designated from the outside, the light color is closer to the color temperature of the first light source unit.

On the other hand, in the present embodiment, each of the first control unit IC1 and the second control unit IC2 maintains the ratio of the plurality of dimming command values received from the outside, and each of the plurality of dimming command values. Lower. Therefore, it is possible to realize the color temperature designated from the outside while suppressing the output power. Therefore, the illuminating device 100 can be turned on with a target toning degree. Therefore, the performance and the quality of light can be improved. Further, since the color temperature designated from the outside is realized as it is, the emission color of the lighting device 100 can be easily adjusted.

As a first modified example of the present embodiment, the lighting control device 1 may include three or more control units, lighting circuits, and light source units, respectively. As a result, the toning range of the light emitted by the light source unit can be expanded.

The number of control units, lighting circuits, and light source units included in the lighting control device 1 may be plural. In this case, the lighting control device 1 includes a plurality of lighting circuits that respectively light a plurality of light source units, and a control device. The control device includes a plurality of control units that respectively control the plurality of lighting circuits. Each of the plurality of control units receives from the outside all of the plurality of dimming command values corresponding to the plurality of light source units. When the sum of the output powers of the plurality of lighting circuits corresponding to the plurality of dimming command values exceeds the set value, each of the plurality of control units performs its own adjustment so that the sum of the output powers becomes equal to or less than the set value. Decrease the light command value.

Also in the first modification, the plurality of control units are connected in series via the transmission terminal and the reception terminal. Further, the reception terminal of the first control unit of the plurality of control units is connected to the transmission terminal Tx0 of the control unit 12. The transmission terminal of the last control unit of the plurality of control units is connected to the reception terminal Rx0 of the control unit 12. Thereby, each control unit can receive all the dimming command values.

Further, in the present embodiment, the ratio of the plurality of dimming command values received from the outside is maintained, but the present invention is not limited to this. As a second modified example of the present embodiment, each of the plurality of control units maintains the ratio of the plurality of dimming command values received from the outside so that the sum of the output power is equal to or less than the set value. The dimming command value processed by itself may be lowered. For example, each control unit may change the ratio of a plurality of dimming command values within the range where the user does not feel uncomfortable. In this case as well, since each of the plurality of dimming command values decreases, compared to the case where only one of the plurality of dimming command values is adjusted, the light emission amount of the plurality of light sources designated from the outside The difference between the ratio and the actual light emission state can be suppressed.

Further, in the present embodiment, the response signal is generated when the communication signal addressed to the own control unit is received (steps S2 and S3). As a third modification of this embodiment, the control unit that generates the response signal may be fixed to a specific control unit. For example, when the control unit that transmits the response signal is the first control unit IC1, the first control unit IC1 transmits the response signal regardless of which control unit receives the communication signal. In addition, the second control unit IC2 transmits the received communication signal as it is.

FIG. 5 is a flowchart illustrating the operation of the first controller IC1 according to the fourth modification of the first embodiment. In the fourth modification, the dimming rate limit S is set to a value other than 100%. Steps S1 to S7 are the same as those in the first embodiment. In step S208, the first control unit IC1 compares the total dimming rate with the dimming rate limit S. Here, the dimming rate limit S is 120%, for example.

When the sum of the first dimming rate T1 and the second dimming rate T2 exceeds the dimming rate limit S, the first control unit IC1 calculates the sum of the first dimming rate T1 and the second dimming rate T2. A new first dimming rate S1 is calculated so as to match the dimming rate limit S (step S209). The method of calculating the new first dimming rate S1 is the same as step S9 except that the value of S is different. The subsequent steps are the same as those in the first embodiment.

FIG. 6 is a diagram showing the relationship between color temperature and output power in the fourth modification of the first embodiment. By setting the dimming rate limit S, the dimming rate, which is the sum of the dimming rates of the first control unit IC1 and the second control unit IC2, can be changed so as to fall below or exceed the full-light lighting. Therefore, it is possible to easily change the specifications and the design. Particularly, when it is desired to increase the light output, the light output can be easily increased by setting the dimming rate limit S=120%, for example. At this time, if the ratio between the first dimming command value and the second dimming command value is maintained, it is possible to prevent the user from feeling a sense of discomfort with respect to the mixed color temperature.

Further, the output power width of the common power supply circuit such as the PFC circuit 15 that supplies DC power to the first lighting circuit 21 and the second lighting circuit 22 can be narrowed within a certain range. Therefore, the load on the power supply circuit can be suppressed. By narrowing the output power width within a certain range, it is possible to design in the narrow range without setting the output power width in a wide range. Therefore, the design becomes easy. In addition, downsizing of parts and cost reduction can be realized.

In the case where one of the first light source unit 11-1 and the second light source unit 11-2 is turned on at the dimming rate that matches the dimming rate limit S, and the other light source unit is turned on from the state of being turned off. Also, the combined dimming rate can be reliably limited to the dimming rate limit S or less. In particular, when only one of the first light source unit 11-1 and the second light source unit 11-2 is turned on at a high dimming rate of 95%, for example, when both light source units are turned on, illumination is performed. It is possible to prevent the device 100 from becoming too bright.

Further, in the present embodiment, each of the plurality of control units reduces the dimming command value processed by itself such that the sum of the output powers becomes equal to or less than the set value. As a fifth modified example of the present embodiment, when the sum of the output powers of the plurality of lighting circuits corresponding to the plurality of dimming command values is smaller than the set value, each of the plurality of control units outputs the sum of the output powers. The dimming command value processed by itself may be increased so as to match the set value. As a result, the output power can be maintained constant regardless of the dimming command value from the outside.

Further, as a sixth modification of the present embodiment, each of the plurality of control units turns on the corresponding light source unit with a predetermined dimming command value when a plurality of dimming command values are not input from the outside. You may let me. The first control unit IC1 and the second control unit IC2 store the dimming ratio in advance. The first control unit IC1 and the second control unit IC2 turn on the first light source unit 11-1 and the second light source unit 11-2, respectively, based on the dimming rate stored in advance.

When a plurality of dimming command values are not input from the outside, the control may be performed so that the total dimming rate becomes 100%, for example. Specifically, the first control unit IC1 and the second control unit IC2 both set the first light source unit 11-1 and the second light source unit 11-2 to 50%. Further, the first control unit IC1 and the second control unit IC2 may set one of the first light source unit 11-1 and the second light source unit 11-2 to 100% and the other to 0%. Not limited to this, for example, one of the first light source unit 11-1 and the second light source unit 11-2 may be set to 50%, the other to 30%, and the total dimming rate may be controlled to be less than 100%. ..

The predetermined dimming command value may be a dimming command value immediately before received from the outside. Accordingly, even when the dimming command value is not input to the lighting control device due to a failure of the dimming controller or a disconnection of the communication line, the light source unit can be turned on.

The lighting control device 1 of the present embodiment can be applied to various lighting devices including a plurality of light source units capable of performing color adjustment. The lighting control device 1 may be used for, for example, a downlight, a pendant type light, a high ceiling lighting, or the like.

Further, the plurality of light source units according to the present embodiment have different color temperatures. The present invention is not limited to this, and the plurality of light source units may have different light emitting directions, light spreading angles, arrangement positions, and the like.

These modifications can be appropriately applied to the lighting control device and the lighting device according to the following embodiments. Since the lighting control device and the lighting device according to the following embodiments have a lot in common with the first embodiment, the differences from the first embodiment will be mainly described.

Embodiment 2.
FIG. 7 is a circuit block diagram of illumination device 300 according to the second embodiment. The lighting device 300 includes a lighting control device 301. In the lighting control device 301, the communication terminal of the control unit 12 is connected in parallel to the communication terminal of the first control unit IC1 and the communication terminal of the second control unit IC2. As a result, a plurality of dimming command values are input in parallel to the plurality of control units.

That is, the first control unit IC1 reception terminal Rx1 and the second control unit IC2 reception terminal Rx2 are connected in parallel with the transmission terminal Tx0 of the control unit 12 via the terminal unit CN3. As a result, each of the first control unit IC1 and the second control unit IC2 can receive a communication signal from the outside. The transmission terminal Tx1 of the first control unit IC1 and the transmission terminal Tx2 of the second control unit IC2 are connected in parallel with the reception terminal Rx0 of the control unit 12 via the terminal unit CN3. Accordingly, each of the first control unit IC1 and the second control unit IC2 can transmit the response signal to the outside.

The signal transmitted from the communication terminal of the control unit 12 is received by both the first control unit IC1 and the second control unit IC2. Therefore, each control unit can refer to the dimming command value transmitted to the other control unit. As a result, as in the first embodiment, the ratio between the first dimming command value and the second dimming command value is set so that the total power of the first lighting circuit 21 and the second lighting circuit 22 does not exceed a certain value. Can be maintained.

Further, the transmission terminal Tx1 of the first control unit IC1 and the transmission terminal Tx2 of the second control unit IC2 transmit the response signal to the outside. For this reason, as in the first embodiment, the lighting control device 301 can perform bidirectional communication with the control unit 12.

In the present embodiment, the first control unit IC1 and the second control unit IC2 receive the communication signals from the control unit 12 all at once. At this time, if both the first control unit IC1 and the second control unit IC2 transmit the response signal to the control unit 12, the response signals may collide. As a result, a communication error may occur. Further, the control unit 12 may receive the response signal doubly in one communication, and the communication may not be established.

In order to avoid such a collision of response signals, in the lighting control device 301, only one of the first control unit IC1 and the second control unit IC2 transmits the response signal. This enables bidirectional wired communication between the lighting control device 301 and the control unit 12.

The control unit 12 first transmits a communication signal whose destination is the first control unit IC1, and then transmits a communication signal whose destination is the second control unit IC2. Therefore, the control unit designated as the destination may return the response. Thereby, the control unit 12 can confirm that at least communication with the control unit designated as the destination has been established.

Not limited to this method, the control unit that transmits the response signal may be fixed. Thereby, the control unit 12 can confirm that communication with at least the control unit that transmits the response signal has been established.

In addition, in the present embodiment, the communication between the control unit 12 and the lighting control device 301 can be performed in the same communication time as the bidirectional wired communication when the number of control units is one. For example, consider a case where communication time from the transmission terminal to the reception terminal requires about 8 ms. At this time, in the first embodiment, the communication time from when the control unit 12 transmits the communication signal to when the control unit 12 receives the response signal via the first control unit IC1 and the second control unit IC2 is It is about 24 ms. On the other hand, in the present embodiment, since the plurality of control units are connected in parallel with the control unit, the communication time from when the control unit 12 transmits the communication signal to when the response signal is received is about 16 ms. is there.

Further, in FIG. 7, both the transmission terminal Tx1 of the first control unit IC1 and the transmission terminal Tx2 of the second control unit IC2 are connected to the control unit 12. Not limited to this, at least one of the plurality of control units may be connected to the terminal unit CN3 so that the response signal can be transmitted to the outside. For example, when the control unit that transmits the response signal is fixed, only the transmission terminal of the control unit that transmits the response signal may be connected to the control unit 12.

Embodiment 3.
FIG. 8 is a circuit block diagram of illumination device 400 according to the third embodiment. The lighting device 400 includes a lighting control device 401. The lighting control device 401 has one control unit IC0 as a control device. The communication terminal of the control unit IC0 is connected to the communication terminal of the control unit 12.

The transmission terminal Tx0 of the control unit 12 is connected to the reception terminal Rx of the control unit IC0 via the terminal portion CN3. The transmission terminal Tx of the control unit IC0 is connected to the reception terminal Rx0 of the control unit 12 via the terminal unit CN3. Accordingly, the control unit IC0 can receive the first dimming command value for the first lighting circuit 21 and the second dimming command value for the second lighting circuit 22 by using the bidirectional wired communication.

The control unit IC0 outputs a switching signal for operating the switching element Q1 from the output terminal P1. The switching signal is received at the terminal Vref1 of the driver DRV1 of the first lighting circuit 21. The driver DRV1 is a MOSFET driver. The first controller IC1 switches the switching element Q1 via the driver DRV1.

The control unit IC0 also outputs a switching signal for operating the switching element Q2 from the output terminal P2. The switching signal is received by the Vref2 terminal of the driver DRV2 of the second lighting circuit 22. The driver DRV2 is a MOSFET driver. The control unit IC0 switches the switching element Q2 via the driver DRV2.

Further, the control unit IC0 calculates the sum of the received first dimming rate T1 and second dimming rate T2, as in the second embodiment. When the sum of the first dimming rate T1 and the second dimming rate T2 is less than or equal to the dimming rate limit S, the control unit IC0 controls the first lighting circuit 21 according to the first dimming rate T1, and The second lighting circuit 22 is controlled according to the dimming rate T2.

When the sum of the first dimming rate T1 and the second dimming rate T2 is larger than the dimming rate limit S, the control unit IC0 calculates a new first dimming rate S1 and a new second dimming rate S2. To do. That is, the control unit IC0 lowers each of the plurality of dimming command values so that the sum of the output powers becomes equal to or less than the set value. The control unit IC0 controls the first lighting circuit 21 according to the new first dimming rate S1, and controls the second lighting circuit 22 according to the new second dimming rate S2. Therefore, the same effect as that of the second embodiment can be obtained.

Fourth Embodiment
FIG. 9 is a circuit block diagram of the illumination device 500 according to the fourth embodiment. The lighting device 500 has a dimmer 512 instead of the control unit 12. Further, the lighting device 500 includes a dimming IF circuit 519 between the first control unit IC1 and the second control unit IC2 and the terminal unit CN3. Other configurations are similar to those of the second embodiment.

The dimmer 512 outputs a PWM signal, which is a dimmer signal, to the terminal portion CN3. The first control unit IC1 and the second control unit IC2 receive the PWM signal via the dimming IF circuit 519. The PWM signal transmitted from the dimmer 512 is input to the input terminal DIM1 of the first controller IC1 and the input terminal DIM2 of the second controller IC2 via the dimmer IF circuit 519. Further, in the present embodiment, the transmission terminal Tx1 of the first control unit IC1 and the transmission terminal Tx2 of the second control unit IC2 are not used.

FIG. 10 is a diagram showing an example of the relationship between the DUTY ratio of the dimming signal and the dimming rate. The first dimming rate T1 of the first lighting circuit 21 and the second dimming rate T2 of the second lighting circuit 22 are transmitted to the first control unit IC1 and the second control unit IC2 as the DUTY ratio of the dimming signal. A DUTY ratio of 5% of the dimming signal corresponds to an all-light state with a dimming ratio of 100%. Further, the DUTY ratio of 90% of the dimming signal corresponds to the off state with the dimming ratio of 0%.

FIG. 11 is a diagram showing an example of the relationship between the period of the dimming signal and the dimming rate. The first dimming rate T1 and the second dimming rate T2 may be transmitted to the first control unit IC1 and the second control unit IC2 as the period of the dimming signal. A frequency of the dimming signal of 100 Hz, that is, a period of 10 ms corresponds to an all-light state with a dimming rate of 100%. Further, the frequency of the dimming signal of 1 kHz, that is, the period of 1 ms corresponds to the off state with the dimming rate of 0%.

The dimmer 512 sequentially outputs a plurality of dimming signals having different DUTY ratios or periods. Each of the first control unit IC1 and the second control unit IC2 receives all of the plurality of dimming signals. Accordingly, each of the first control unit IC1 and the second control unit IC2 can grasp the first dimming rate T1 and the second dimming rate T2. Therefore, as in the second embodiment, the ratio between the first dimming command value and the second dimming command value is set so that the total power of the first lighting circuit 21 and the second lighting circuit 22 does not exceed a certain value. Can be maintained.

Note that the technical features described in each embodiment may be used in an appropriate combination.

1, 301, 401, 501 Lighting control device, 100, 300, 400, 500 Lighting device, 11-1 1st light source part, 11-2 2nd light source part, 12 Control unit, 13 Rectifier circuit, 14 Inrush current suppression circuit , 15 PFC circuit, 17 external receiving terminal, 18 external transmitting terminal, 21 first lighting circuit, 22 second lighting circuit, 512 dimmer, AC commercial power supply, C1, C2 capacitor, CN1, CN2, CN3 terminal section, D1 , D2 diode, GND circuit reference potential, IC0 control section, IC1 first control section, IC2 second control section, L1, L2 coil, Q1, Q2 switching element, R1, R2 resistance

Claims (9)

A plurality of lighting circuits for respectively lighting a plurality of light sources,
A control device that receives a plurality of dimming command values respectively corresponding to the plurality of light sources from the outside, and controls the plurality of lighting circuits,
Equipped with
The control device, when the sum of the output power of the plurality of lighting circuits according to the plurality of dimming command values exceeds a set value that is a predetermined value, the sum of the output power is equal to or less than the set value. The lighting control device is characterized in that each of the plurality of dimming command values is lowered so that The lighting control device according to claim 1, wherein the control device maintains a ratio of the plurality of dimming command values and lowers each of the plurality of dimming command values. The control device includes a plurality of control units that respectively control the plurality of lighting circuits,
Each of the plurality of control units receives the plurality of dimming command values, and when the sum of the output powers exceeds the set value, the sum of the output powers is equal to or less than the set value. The lighting control device according to claim 1 or 2, wherein a dimming command value to be processed by itself is reduced among the dimming command values. An external receiving terminal to which the plurality of dimming command values are input from the outside,
The lighting control device according to claim 3, wherein the plurality of control units are connected in series to the external receiving terminal, and each of the plurality of control units receives the plurality of dimming command values. The lighting control device according to claim 3, wherein the plurality of dimming command values are input in parallel to the plurality of control units. The plurality of dimming command values are a plurality of dimming rates,
When the sum of the plurality of dimming command values exceeds a predetermined value, the control device controls the plurality of dimming commands so that the sum of the plurality of dimming command values becomes equal to or less than a predetermined value. The lighting control device according to any one of claims 1 to 5, wherein each of the values is reduced. 7. The control device turns on the plurality of light sources with a predetermined dimming command value when the plurality of dimming command values are not input from the outside. The lighting control device according to. The lighting control device according to claim 7, wherein the predetermined dimming command value is a dimming command value immediately before received from the outside. A lighting control device according to any one of claims 1 to 8;
The plurality of light sources,
A control unit for inputting the plurality of dimming command values to the lighting control device,
A lighting device comprising:

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