JP5401939B2 - LED lighting device and lighting apparatus - Google Patents

Description

The present invention relates to an LED illumination lamp lighting device that lights an LED illumination lamp and an illumination fixture including the same.

  A light emitting diode lighting device for lighting LED lighting lamps composed of a large number of light emitting diodes in series is known (for example, see Patent Document 1). The lighting circuit described in Patent Document 1 boosts an alternating rectified voltage with a boost chopper, smoothes it, supplies a plurality of series circuits composed of a plurality of light emitting diodes to an LED lighting lamp connected in parallel, and lights up, The boost chopper is controlled by a control circuit so that it can be dimmed, and the power factor can be improved.

  Depending on the number of LED lamps in series and the power supply voltage used, the LED lamps can be turned on using an LED lamp lighting circuit mainly composed of a step-down chopper, or a combination of a step-up chopper and a step-down chopper connected in cascade. May be.

  On the other hand, when the LED lighting is in an abnormal lighting state, the switching operation of the switching element is stopped, and the output of the LED lighting lamp lighting device is reduced or the output is reduced, thereby protecting the LED lighting and protecting its safety. A safety circuit can be arranged in the lighting device.

Japanese Patent Application Laid-Open No. 11-066771

However, even in the improved safety as activating the safety circuit when an abnormal lighting state, further safety circuit smoke when the event that becomes inoperative, so as not to reach to a fire hazard It is desirable to ensure higher safety.

According to the present invention, when the switching element of the step-down chopper that turns on the LED lighting lamp is destroyed in the short-circuit mode without adding a special circuit means, it is possible to ensure safety so as not to cause smoke, fire, etc. It is an object of the present invention to provide a lighting device that uses an LED illumination lamp with high safety as a light source and a lighting fixture including the same.

The LED lighting lamp lighting device of the present invention is connected to a DC power source that outputs a DC voltage obtained by rectifying a commercial AC voltage at the input end , and the commercial AC voltage is changed to a high DC output voltage for the LED light source. boosting chopper for boosting, LED lighting lamp lighting circuit and having a step-down chopper to be output from the output end of the DC output voltage of the boost chopper steps down the DC voltage LED light source is turned on; the step-down chopper of the LED illumination lamp lighting circuit output A plurality of LED light sources that are connected to the end and set so that at least some LED light sources are destroyed in the open mode by the DC output voltage of the step-up chopper that appears at the output end of the step-down chopper when the switching element of the step-down chopper breaks down in the short-circuit mode An LED illuminating lamp having a series circuit composed of LED light sources.

  The present invention allows the following aspects.

The LED lighting lamp lighting circuit is formed by connecting a step-up chopper and a step-down chopper in cascade between a commercial AC power source and an output terminal connecting the LED lighting . In order to ensure safety when the switching element of the step-down chopper is destroyed in the short-circuit mode, the LED light source is instantaneously destroyed in the open mode when the DC output voltage of the step-up chopper is applied to the LED lighting. The DC output voltage of the boost chopper is set high. Note that the LED lighting lamp lighting circuit is preferably configured to light the LED lighting lamp by constant current control. Then, the constant current control of the LED illumination lamp, for example, by performing the feedback control the load current flowing to the LED lighting loads directly or indirectly detected, it is possible to achieve this.

Thus, the step-down chopper of the LED lighting lamp lighting circuit has a circuit configuration in which the LED lighting lamp of the load is connected to the input terminal of the step-down chopper via the switching element and the inductor in series. However, if it breaks down in the short circuit mode, the output terminal of the step-up chopper and the LED illuminating lamp are directly connected via the inductor by the short-circuited switching element. Then, the output terminal of the step-down chopper of the LED illumination lamp lighting circuit, a high DC output voltage of the boost chopper is present. In the present invention, the value of the high DC output voltage of the step-up chopper is set to the following value. That is, since the set value is too high for the LED lighting, at least a part of a series circuit composed of a plurality of LED light sources constituting the LED lighting when the DC output voltage is applied. Is the value that destroys in the open mode instantly. Therefore, in the present invention, when the above situation occurs, a high DC output voltage of the boost chopper appears at the output end of the LED lighting lamp lighting circuit, and a plurality of LED light sources connected in series with the LED lighting lamp. All or part of it instantly destroys in open mode. As a result, the LED illumination lamp is turned off to notify the user or the like of the occurrence of an abnormal situation, and at the same time, the load side portion from the output end of the LED illumination lamp lighting circuit to the LED illumination lamp is avoided from the risk of smoke and ignition.

  Further, in the present invention, in a mode in which a plurality of LED modules composed of a series circuit of a plurality of LED light sources are connected in series to constitute a load LED illumination lamp, the LED illumination lamp lighting circuit is controlled at a constant current When a part of the LED modules reaches a short-circuit failure, the safety circuit can be configured to operate by utilizing the corresponding decrease in the output voltage of the LED lighting lamp lighting circuit. When the safety circuit is activated, the load side safety can be achieved by stopping or reducing the output of the LED lighting lamp lighting circuit.

  That is, the safety circuit is provided with an abnormal lighting state detection means, and when the detected value reaches a preset threshold value, it is determined that an abnormal lighting state has occurred, and switching of the switching element is performed by stopping oscillation, for example. Is configured to stop the output of the lighting lamp lighting circuit or to reduce the output of the lighting lamp lighting circuit.

Abnormal lighting state detecting means can detect an electrical value, a variety of physical phenomena such as light emission level of the LED lighting of the LED illumination lamp lighting lamp lighting circuit. For example, a load voltage (or output voltage) detection means or / and a load current detection means, an optical sensor that detects light emission of an LED illumination lamp, or the like can be used.

  Specific operating conditions of the safety circuit are as follows. That is, when the LED illumination lamp is normal, the normal output voltage output from the LED illumination lamp lighting circuit is V (V), and the abnormal voltage detection threshold when detecting the abnormal lighting state is V ′ (V). The abnormal voltage detection threshold value V ′ and the normal output voltage V are set in advance so that the abnormal voltage detection threshold value satisfying both the mathematical formulas (V−V / n + 13) <V ′ <V and 13 <V / n, When the output voltage of the LED lighting lamp lighting circuit reaches the abnormal voltage detection threshold, the output of the LED lighting lamp lighting circuit is stopped or lowered.

  The above-described safety circuit can cope with a short-circuit failure of the LED module of the load. However, in order to perform a safe operation against the overvoltage of the output voltage of the LED lighting lamp lighting circuit, separately for overvoltage detection means and output voltage reduction. It is necessary to provide the control means. That is, a control circuit for high and low binary output voltages can be added.

However, since the overvoltage state may be caused by a short circuit failure of the series switching element, it is effective if the LED light source of the LED lighting lamp is destroyed by the above-described means of the present invention. Thereby, the circuit configuration can be simplified and the LED lighting device can be provided at low cost.

The lighting fixture of this invention has comprised the lighting fixture main body and the LED lighting lamp lighting device. The luminaire may be provided with an LED illuminating lamp, and its use is generally for illumination purposes, but is not limited thereto. The luminaire main body refers to all remaining parts from which the lighting device has been removed from the luminaire. The LED illumination lamp lighting device has the above-described configuration in the present invention.

According to the present invention, when the switching element of the step-down chopper breaks down in the short-circuit mode, a high DC output voltage of the step-up chopper is applied to the LED illumination lamp via the output end of the step-down chopper. All or part of the LED light source of the LED lighting lamp configured with a series circuit consisting of is instantaneously destroyed in the open mode and the LED lighting lamp is extinguished. Since the load side part from the output end of the LED lighting lamp lighting circuit to the LED lighting lamp is avoided from the danger of smoke and ignition, the LED lighting lamp with higher safety without adding special circuit means It is possible to provide an LED illuminating lamp lighting device using a light source as a light source and a lighting fixture including the same.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 to 3 show a first embodiment for carrying out the LED illumination lamp lighting device of the present invention, FIG. 1 is a circuit diagram showing the whole LED illumination lamp lighting device, and FIG. 2 is a configuration of the LED illumination lamp. FIG. 3 is a voltage waveform diagram showing the relationship between the abnormal voltage detection threshold and the normal output voltage.

  In this embodiment, the LED illumination lamp lighting device includes an LED illumination lamp lighting circuit OC, an LED illumination lamp LED, and a control means CC, and is supplied with power from a commercial AC power supply AC.

  In this embodiment, the LED lighting lamp lighting circuit OC includes a rectified DC power supply RDC, a step-up chopper BUC, a step-down chopper SDC, a constant current circuit CCR, and a dimming signal output means DSG.

  The rectified DC power supply RDC is composed of a bridge-type full-wave rectifier circuit Rec having an AC input terminal connected to a commercial AC power supply AC, and outputs a non-smooth DC voltage.

The step-up chopper BUC includes a series circuit of an inductor L1 and a switching element Q1 connected to the DC output terminal of the rectified DC power supply RDC, a series circuit of a flywheel diode D1 and a smoothing capacitor C1 connected in parallel to the switching element Q1, and output voltage detection. A circuit VD1 is provided, and a boosting operation and a power factor improving operation are performed under the control of the control means CC described later. Then, a high DC voltage, for example, a voltage of 450 V is output to the LED light source by the boosting operation. The switching element Q1 is made of a MOSFET.

  The output voltage detection circuit VD takes out the divided output voltage from the voltage dividing circuit connected in parallel to the output terminal of the LED lighting lamp lighting circuit OC, and inputs the output voltage to the control means CC described later. The voltage dividing circuit is constituted by a series circuit of resistors R2 and R3, and a terminal voltage of the resistor R3 is output via a capacitor C3 connected in parallel.

  The step-down chopper SDC includes a switching element Q2 as a current control element connected between both ends of a smoothing capacitor C1 that is an output end of the step-up chopper BUC and a series circuit of a flywheel diode D2, an inductor L2 connected in parallel to the flywheel diode D2, and A series circuit of the capacitor C2 and a load current detection circuit ID are provided, and a step-down operation is performed under the control of the control means CC described later. Then, for example, a voltage of 100 V is output to the output terminal as the output voltage of the LED lighting lamp lighting circuit OC by the step-down operation. The switching element Q2 is made of a MOSFET. Further, the load current detection circuit ID is configured to detect the load current with the resistor R1 and control-input it to the control means CC.

  In this embodiment, the LED lighting LED is such that when the number of LED light sources connected in series is destroyed in the short-circuit mode, at least some of the LED light sources are destroyed in the open mode when the current control element of the step-down chopper SDC is destroyed. It is set to do. For example, the number of LED light sources connected in series is 32, and when the LED lighting LED LED is normal, a voltage of about 3.1 V is applied to each LED to light up.

  Further, as shown in FIG. 2, the LED illumination lamp LED is formed by connecting a plurality of, for example, two LED modules M1 and M2 in series, and is connected to the output end of the LED illumination lamp lighting circuit OC. Each of the LED modules M1 and M2 has a structure including a single connector CN in which a plurality of each, in the above case, a series circuit composed of 16 LED light sources and a pair of terminals connected at both ends thereof are arranged close to each other. is there. In the single connector CN, a pair of terminals are arranged close to each other, and both ends of a series circuit composed of a plurality of LED light sources are connected thereto. Therefore, the series connection body of the some LED module M1 and M2 is connected in series via the single connector CN.

  The dimming signal output means DSG is a means for generating and outputting a dimming signal that is arranged when the LED lighting LED is lit by dimming, and is arranged as desired. In addition, when not adjusting light, it does not need to arrange | position. The arrangement position of the dimming signal output means DSG is a position close to the main part of the LED lighting lamp lighting device including the step-up chopper SUC and the step-down chopper SDC, for example, an embodiment mounted on the same wiring board as the main part. Good. Further, it may be arranged at a position separated from the main part.

  Further, the dimming signal output means DSG is not particularly limited in the form of the dimming signal to be output. For example, a duty signal whose pulse duty changes according to the dimming degree, a digital signal obtained by digitizing the dimming degree, a variable voltage signal whose voltage value changes according to the dimming degree, and the like can be selectively employed as appropriate. Further, the dimming signal output from the dimming signal output means DSG may change continuously or stepwise. In the present embodiment, the dimming signal is composed of a voltage pulse train whose duty changes in accordance with the dimming ratio.

  The control means CC is means for controlling the step-up chopper BUC and the step-down chopper SDC, and further incorporates a safety circuit function. As a starting sequence, when power is supplied to the LED lighting device, the power is turned on by performing a control operation divided into, for example, a standby mode and a run mode, which will be described later, as desired.

  Further, the control means CC controls the output of at least one of the step-down chopper SDC and the step-up chopper BUC in accordance with the dimming signal output from the dimming signal output means DSG in order to dimm the LED lighting LED. Thus, a dimming control operation for dimming the LED lighting LED can be performed. Note that it is not necessary to integrally control the step-up chopper BUC and the step-down chopper SDC, and both can be controlled exceptionally. For example, a configuration in which a dedicated control unit is integrated in advance as a part of the boost chopper BUC can be used.

  In the aspect in which the dimming control operation is performed, the output control of at least one of the step-down chopper SDC and the step-up chopper BUC is performed by a predetermined dimming characteristic set in the control unit CC and a dimming signal output from the dimming signal output unit. Based on the correlation. The dimming characteristics can be appropriately set as desired according to the type of illumination lamp to be used. For example, the dimming characteristic in which the light amount and the dimming degree of the LED lighting LED LED continuously and linearly change, or the dimming in which the light amount and the dimming degree of the LED lighting LED LED change in a predetermined non-linear manner. It is possible to make it a characteristic, or to make it a dimming characteristic in which the light quantity of the LED lighting LED LED changes stepwise.

  Further, the control means CC is constituted by an analog circuit so that at least a part for executing the standby mode and the run mode in the power-on control of the start sequence will be described later. However, the portion that performs other control operations may be configured mainly by an analog circuit or a microcomputer, or may be a hybrid configuration of a microcomputer and an analog circuit.

  In order to control the boost chopper BUC, a drive signal composed of a pulse voltage is supplied to the switching element Q1 of the boost chopper BUC. Also, feedback control is performed so that the output voltage controlled and input from the output voltage detection circuit VD of the step-up chopper BUC becomes a predetermined value, thereby controlling the duty of the drive signal to a predetermined value.

To control the step-down chopper SDC supplies a drive signal composed of a pulse voltage to the switching element Q2. In addition, feedback control is performed so that the load current controlled and input from the load current detection circuit ID of the step-down chopper SDC is constant, and in the case of dimming, the drive signal is PWM-controlled according to the dimming signal.

  The safety circuit function built in the control means CC includes a load voltage detection circuit VD and a threshold setting circuit. The output voltage of the LED lighting lamp lighting circuit OC is taken out by the load voltage detection circuit VD. The threshold setting circuit is configured mainly by a comparator, for example, and the detection voltage of the load voltage detection circuit VD is applied to the inverting input terminal, and the reference voltage obtained from the resistance voltage dividing circuit is applied to the non-inverting input terminal. The abnormal voltage detection threshold value V ′ on the side is set. This threshold value is set when one of the two LED modules M1 and M2 is short-circuited, and is set 13V higher than V / 2 as shown in FIG.

  Then, when a part of the LED lighting LED is short-circuited and the output voltage of the LED lighting lamp lighting circuit OC becomes lower than the normal value V and reaches the abnormal voltage detection threshold V ′, the output of the comparator is Then, the control means CC performs the control operation, so that the output of the LED lighting lamp lighting circuit OC is stopped or lowered to a safe level.

Next, the basic circuit operation of the LED lighting device will be described. That is, by operating the step-up chopper BUC of the LED lighting lamp lighting circuit OC, the voltage is raised to be higher than the voltage of the commercial AC power supply AC and to a high DC voltage for the LED light source , and the output voltage detection circuit A DC voltage feedback-controlled using the feedback voltage obtained from VD is output from boost chopper BUC. In addition, the power factor of the LED lighting device can be improved. For the LED light source, the high DC voltage is a value at which the LED light source instantaneously breaks in the open mode when the switching element of the step-down chopper SDC fails in the short circuit mode.

  The output voltage of the step-up chopper BUC is applied to the input terminal of the step-down chopper SDC. Thereby, the step-down chopper SDC performs a step-down operation.

  Then, a DC voltage adjusted to a required value in the step-down chopper SDC with respect to the load LED lighting LED LED appears at the output end thereof. As a result, a load current flows through the LED lighting LED connected to the output terminal as a load of the step-down chopper SDC, so that the LED lighting LED is turned on. When the LED lighting LED is a light emitting diode, the lighting at this time is performed under constant current control by the cooperation of the load current detection circuit ID of the step-down chopper SDC and the control means CC.

Then, since the high DC voltage 450V for LED light sources of the step-down chopper SDC of switching element Q2 boost chopper BUC during the short mode failure appears at the output terminal of the step-down chopper SDC, the LED lighting LED of the LED light source Since an abnormally high voltage of about 14 V is applied to each LED, the LED light source instantaneously breaks in the open mode. As a result, the load current is cut off, so that smoke and fire are not caused.

  When the dimming signal sent from the dimming signal output means DSG is input to the control unit of the step-down chopper SDC, the control unit generates a PWM-controlled drive signal corresponding to the dimming signal and switches the step-down chopper SDC. Supply to element Q2. As a result, since the reference value for constant current control of the load current is changed according to the dimming signal, the LED lighting LED performs dimming lighting of the light output corresponding to the dimming signal.

The circuit diagram which shows the whole 1st form for implementing the LED illumination light lighting device of this invention Similarly, a circuit diagram illustrating the configuration of the LED lighting Similarly, a voltage waveform diagram showing the relationship between the abnormal voltage detection threshold and the normal output voltage

Explanation of symbols

AC: commercial AC power supply, BUC: boost chopper, CC: control means, DSG: dimming signal output means, ID: load current detection circuit, LED: LED illumination lamp, OC: LED illumination lamp lighting circuit, Q2: switching element , RDC: Rectified DC power supply, SDC: Step-down chopper, VD: Output voltage detection circuit

Claims (2)

The input end is connected to a DC power source obtained by rectifying the commercial AC voltage, and the commercial AC voltage is boosted to a high DC voltage and output to the LED light source. The high DC output voltage of the boost chopper is the LED light source. An LED lighting lamp lighting circuit including a step-down chopper that steps down to a DC voltage to light and outputs from the output end ;
At least a part of the LED light source is connected to the output terminal of the step-down chopper of the LED lighting lamp lighting circuit and the high DC output voltage of the step-up chopper that appears at the output terminal of the step-down chopper when the switching element of the step-down chopper breaks down in the short-circuit mode. and LED lighting constructed with a series circuit comprising a plurality of LED light sources configured to destroyed instantly open mode;
LED lighting lamp lighting device characterized by comprising. A lighting fixture body;
The LED illumination lamp lighting device according to claim 1, which is disposed in a lighting fixture body;
The lighting fixture characterized by comprising.

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