KR100960190B1 - Dimmer - Google Patents

Abstract

An object of the present invention is to provide a dimming device capable of switching between the dimming output mode and the direct power output mode, and reducing the rating of the relay for switching the modes.

The light control device according to the present invention includes a phase control circuit 1 having a thyristor 1a, 1b inserted into an AC power supply line 8 to control an AC voltage supplied to a load 7, and a phase control circuit. A current sensor 3 for monitoring the output current of the circuit, a relay 4 connected in parallel to a phase control circuit to turn on and off an alternating voltage, and an alternating current power supply voltage when starting output in a direct power output mode. The phase control circuit is turned on at the zero cross timing of the phase. When the output current of the phase control circuit reaches a predetermined value or less, the relay is turned on and an AC power supply voltage is output. When the output is stopped, the phase control is turned off. The control means 5 which turns off a circuit is provided.

Description

Dimmer {Dimmer}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dimmer having a phase control circuit for phase control using a thyristor.

In a dimming device for illuminating an incandescent lamp load using a phase controlled dimming device using a semiconductor switch element, a large inrush current flows when energization is started while the filament of the incandescent lamp is cold. Therefore, at the start of energization, by applying a voltage suppressed through the power transformer, the inrush current is kept low, the timer circuit controls the relay for switching power, and the power transformer is disconnected after the inrush current does not flow. The structure which made it come out is known (refer patent document 1).

On the other hand, when the output outlet of a light control device is used as a power supply of the equipment used in a studio, etc., it is performed to switch a phase control circuit output into a direct power output mode by a relay, and to supply power.

[Patent Document 1] Japanese Patent Laid-Open No. 2000-223286

In the above-described phase control dimmer, since the power transformer is used, there is a problem that the apparatus becomes larger and becomes expensive.

In order to switch the dimmer to direct power output mode, the relay contact may melt due to inrush current when the relay is turned on. In addition, when the relay is turned off, the relay contact may be melted by an arc or the like.

In order to solve the above problems, it was necessary to use a relay having a large rating. In addition, in the prior art as described above, in the case of a light load, ON may fail because a sufficient trigger current does not flow for the thyristor to fire.

An object of the present invention is to provide a dimming device capable of switching between a dimming output mode and a direct power output mode and reducing the rating of a relay for switching the modes. Moreover, an object of this invention is to provide the phase control apparatus which prevented the waveform of an output current from being disturbed by reliably firing a thyristor even at light load.

A light control apparatus of the first invention includes a phase control circuit having a thyristor for controlling phase of an AC voltage inserted into an AC power supply line and supplied to a load; A current sensor for monitoring the output current of the phase control circuit; A relay connected in parallel to the phase control circuit to turn on and off an AC voltage; In the direct power output mode, when starting the output, the phase control circuit is turned on at the timing of zero crossing of the AC power supply voltage. When the output current of the phase control circuit reaches a predetermined value or less, the relay is turned on and the AC power supply voltage is output. When the output is stopped, control means for turning off the relay and turning off the phase control circuit is provided.

The present invention allows the following forms. In addition, although it demonstrates centering around 1st invention for the first time, it applies also to other invention if possible.

The phase control circuit is connected to an AC power supply line and is provided with a thyristor as a phase control switch element. The phase control circuit can control the dimming output mode by phase controlling and outputting the AC power supply voltage. In this invention, since the circuit structure for phase control is not specifically limited, this existing type of circuit can be employ | adopted suitably. Typically, a configuration in which a pair of thyristors are anti-parallel connected, a configuration in which thyristors are connected to opposite connection points of the diode bridge, and the like can be selectively used. As the thyristor, three-terminal thyristors such as SCR or two-terminal thyristors such as SSR can be used.

The current sensor is a means for monitoring the output current of the phase control circuit, but the specific means is not particularly limited. For example, a current transformer, a current detection resistor, a semiconductor current detector, or the like can be appropriately used. The insertion position of the current sensor is not limited to a specific circuit position as long as the output current of the phase control circuit can be monitored. For example, the position where only the output current of a phase control circuit flows may be sufficient, and the position which all the load current flows through may be sufficient as it.

Thus, the monitoring output from the current sensor is inputted to the control means described later to cause the control means to perform the necessary control operation in accordance with the current output. On the other hand, if the current sensor is inserted at the position where all the load currents flow, it is possible to monitor the load current and perform desired control such as overcurrent protection even in the direct power output mode.

The relay is connected in parallel to the phase control circuit, and bypasses the phase control circuit, thereby bypassing the phase control circuit, and converting the direct current output mode for directly outputting an alternating voltage from the dimmer without using the phase control circuit. ). Accordingly, the relay not only connects in parallel to the phase control circuit but also allows the parallel connection to a series circuit including other circuit elements, for example, a reactor, if the phase control circuit is included.

In addition, in this invention, the specific structure of a relay is not specifically limited. For example, an electronic relay, an electronic relay, etc. may be sufficient.

The control means is a means for controlling the dimming device so as to be switchable in either the dimming output mode or the direct power output mode. The dimming output mode is an operation mode used for dimming control of an illumination load by operating a phase control circuit to phase control a current supplied to the load. In contrast, the direct power output mode is an operation mode in which the AC power supply voltage is directly output regardless of the phase control circuit. And it can be used, for example, when using a light control apparatus as a power supply, such as a movable lighting apparatus for directing remote control called a moving light.

The control means performs the following control in the direct power output mode.

1. When starting the direct power output

(1) First, the phase control circuit is turned on by zero cross-timing of the AC power supply voltage.

(2) Next, the relay is turned on when the output current of the phase control circuit monitored by the current sensor becomes equal to or less than a predetermined value. At this time, since no inrush current flows through the relay, a small relay having a relatively small current rating can be used.

Thus, the AC power supply voltage is output directly from the dimmer to enter the direct power output mode. In the above description, the predetermined value is a current value when the output current decreases after reaching the load inrush current and reaches a constant value, and the value may be a allowable current value of the relay. In addition, when the dimmer is operating in the direct power output mode, the phase control circuit may be in the OFF state or may be in the ON state from the start of the direct power output. In either case, since the relay is ON, the AC power supply voltage is directly output.

2. When stopping the direct power output

(1) First, turn off the relay. On the other hand, when the phase control circuit is OFF, the phase control circuit is turned ON before the relay is turned OFF. Thus, since the phase control circuit is ON when the relay is OFF, the relay contact does not draw an arc.

(2) Next, the phase control circuit is turned off. When the phase control circuit is turned off, the thyristor is preferably configured to be turned off at zero cross of an alternating voltage.

Further, the control means performs the following control in the dimming output mode. That is, the relay is turned off to supply the phase control signal to the phase control circuit so as to perform the phase control operation.

In addition, it is suitable that the control means mainly comprises digital devices such as a microphone and a digital signal processor (DSP). On the other hand, in order to perform the above-mentioned various control, a control signal can be obtained via the control output from the digital device via the D / A converter.

As another configuration, if desired, for example, a reactor can be connected in series to a phase control circuit, so that a relay can be connected in parallel to the phase control circuit and the series circuit of the reactor. The reactor smoothly starts the load current accompanying the large voltage start of dV / dt by turning on the thyristor and suppresses the generation of noise. On the other hand, a relay can be connected in parallel with the series circuit of a reactor and a phase control circuit.

2nd invention is a structure which removes the influence of the impedance of a reactor at the time of turning on a 1st relay, when connecting a reactor to a phase control circuit in series. In other words, in the second invention, the second relay is connected in parallel to the reactor, and in the direct power output mode, when the output is started, the control means is used to turn on the second relay for the first time and the reactor is short-circuited. Then, as in the sequence of the first invention, the phase control circuit is turned on and the inrush current flows, and a relay connected in parallel to the phase control circuit when the output current reaches a predetermined value or less (in this embodiment, the second relay and the In order to facilitate differentiation of the ", "

Thus, the AC power supply voltage in the direct power output mode can be output. In the second aspect of the invention, the second relay is turned on until the first relay is turned on, so that the influence of the impedance of the reactor when the first relay is turned on can be eliminated. On the other hand, in the direct power output mode, the phase control circuit and the second relay may be in either the OFF state or the ON state.

Next, when the output is stopped, the same sequence as in the first invention described above is assumed.

According to a third aspect of the present invention, when the reactor is connected in series with the phase control circuit, the influence of the reactor impedance is eliminated even when the direct power output mode is stopped. That is, in the third invention, when the reactor is connected in series with the phase control circuit, the second relay is connected in parallel to the reactor as in the second invention, and when the output is started in the direct power output mode. After the control means is first turned on the second relay and the reactor is short-circuited, the phase control circuit is turned on as in the sequence of the first invention, and when the output current is below a predetermined value, the parallel connection is made to the phase control circuit. To turn on the first relay. In this respect, the third invention is the same as the second invention.

Next, in the direct power output mode, when the output is stopped, the second relay and the phase control circuit are turned on in advance. Therefore, when either or both of the second relay and the phase control circuit are turned off in the direct power output mode, the OFF state may be switched to the ON state prior to the stop of the direct power mode. When the above preparation is made, the first relay is turned off, and then the phase control circuit is turned off at zero cross. Finally, the second relay is turned off.

In this way, when the first relay is turned off when the direct power output mode is stopped, the phase control circuit is in the ON state, thereby eliminating arcing and protecting the first relay. Finally, since the phase control circuit is already OFF when the second relay is turned off, the second relay is also protected.

A dimming device of a fourth aspect of the present invention includes a first phase control circuit including a self-extinguishing control element and a phase control circuit inserted into an AC power supply line to control an AC voltage; A second phase control circuit connected in parallel with the first phase control circuit to phase control the AC voltage; Load current detecting means for detecting a load current; In the case of cooperating with the load current detecting means to conduct electricity between half-waves, the first phase control circuit is turned on at zero cross timing, and the second phase is generated when an output current of a predetermined value or more flows in the first phase control circuit. When the control circuit is turned on, the first phase control circuit is turned off, and the load current flowing through the second phase control circuit becomes less than a predetermined value, the first phase control circuit is turned on and the second phase control circuit is turned off. When the output is turned off, a control means is provided for turning off the first phase control circuit and then turning off the second phase control circuit.

The first phase control circuit is provided with a self-extinguishing control element, and is inserted into an AC power supply line, and is controlled by the control means described later when turned on during the AC half-wave, and is turned on at zero cross timing. As the self-extinguishing control element, for example, an IGBT, a MOSFET or the like can be used. In addition, when it is ON by phase control, so-called inclination control which inclines the starting of an electric current, can perform linear ON operation | movement. In addition, an AC power supply line means the line which connects between an AC power supply and a load.

The circuit configuration for phase controlling the AC power supply voltage is not limited to a specific circuit. For example, a structure in which a pair of self-protected control elements are connected in series in reverse polarity, and a diode is connected in parallel in reverse polarity to each of the pair of self-protected control elements, or a pair of vertices facing the diode bridge The structure etc. which connected one self-protection type control element between can be used.

The second phase control circuit is connected to the first phase control circuit in parallel and is turned on when a current equal to or greater than a predetermined value flows in the first phase control circuit by control by a control means described later to control the load current. The control in this case may be conducted through conduction between the AC half-waves, or may be performed to control phase. Since the circuit configuration for enabling phase control of the AC power supply voltage is not stable to a specific circuit, this existing circuit of this kind can be appropriately employed. Typically, a configuration in which a pair of thyristors are connected in parallel and in parallel can be used. As the thyristor, three-terminal thyristors such as SCR or two-terminal thyristors such as SSR can be used.

The load current detecting means is means for detecting a load current. Specific means for detecting the load current is not limited to the specific configuration. For example, a current transformer, a current detection resistor, a semiconductor current detector, or the like can be appropriately used. In addition, the insertion position of the load current detecting means is not limited to a specific circuit position as long as the load current can be detected. For example, it is preferable to insert in series between the output terminal of a phase control apparatus, and the 1st and 2nd phase control circuit. In summary, however, the pair of current detection means may be distributedly arranged by connecting the first and second phase control circuits in series, respectively. In this way, the detection output of the load current detecting means is controlled by inputting the control means described later to perform the necessary control operation.

The control means cooperates with the load current detecting means to perform the following control when conducting conduction between the AC half-waves.

(1) The first phase control circuit is turned on at zero cross timing.

(2) When a current equal to or greater than a predetermined value flows through the first phase control circuit, the second phase control circuit is turned on and the first phase control circuit is turned off. On the other hand, the predetermined value in this case may be a current value that is at least as high as the load current can be started and the thyristor can be surely turned on.

(3) When the load current falls below a predetermined value, the first phase control circuit is turned on and the second phase control circuit is turned off. In addition, the predetermined value in this case may be more than the electric current value of the grade just before the possibility that the thyristor of a 2nd phase control circuit will be unable to turn ON.

(4) When the load current is turned off, the second phase control circuit is turned off after the first phase control circuit is turned off. The second phase control circuit is turned off to zero cross phase after the gate signal is interrupted.

In addition, it is suitable that the control means mainly comprises digital devices such as a microphone and a digital signal processor (DSP). On the other hand, in order to perform the above-mentioned various control, a control signal can be obtained via the control output from the digital device via the D / A converter.

In the first invention, a relay is connected in parallel to a phase control circuit having a thyristor, and in a direct power output mode, when the control means starts output, the phase control circuit is operated at a timing of zero cross of the AC power supply voltage. When the output current of the phase control circuit reaches a predetermined value or less, the relay can be turned on and the AC power supply voltage can be directly output to the direct power output mode.When the direct power output is stopped, the relay is turned off to turn off the phase. Since the control circuit is turned OFF, the circuit configuration for switching to the direct power output mode is simple, and switching to the direct power output mode can be performed by using a relatively small current rating relay. Can provide.

In the second aspect of the present invention, when the reactor is connected in series to the phase control circuit, the second relay is connected in parallel to the reactor, and before the first relay parallel to the phase control circuit is turned on when the direct power output mode is set. By turning ON the second relay, the impedance of the reactor can be prevented from affecting the circuit until the first relay is turned ON, in addition to the effect of the first invention.

In the third aspect of the present invention, when a reactor is connected in series to a phase control circuit, a second relay is connected in parallel to the reactor, and before turning on the first relay parallel to the phase control circuit when the direct power output mode is set. The second relay is turned on, and when the direct power output mode is stopped, the first relay is turned off after the phase control circuit and the second relay are turned on in advance, and then the phase control circuit is turned off. Finally, by turning off the second relay, in addition to the effects of the first and second inventions, the first and second relays can be protected when the direct power output mode is stopped.

In the fourth invention, the following effects of 1. to 4. are achieved.

1. Although the rating of the phase control device is 1 kW, for example, even if the load of about 100 W or less is a light load such as when connected to the phase control device, the control by the control means which cooperates with the load current detection means, The first phase control circuit automatically operates in place of the second phase control circuit. For this reason, it is possible to prevent the thyristor of the second phase control circuit from firing for light load and causing confusion that is inconsistent with the load current waveform.

2. When the load current is activated, the self-protection type control element of the first phase control circuit is first turned on, so that the shortage of current near zero cross is smaller than when the thyristor is turned on from the beginning.

3. When the load current increases, the thyristor turns on, so that a self-repeating control element having a relatively small rating can be used for the first phase control circuit, thereby reducing the cost.

4. When the load current is turned off, the second phase control circuit is turned off after the first phase control circuit is turned off. Therefore, even when the inductive load is connected, the output current can be turned off by zero cross, so the kickback voltage is reduced. Can be prevented.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated with reference to drawings.

1 and 2 show a dimming device as one embodiment for implementing the phase control device of the first invention, FIG. 1 is a circuit diagram, and FIG. 2 is a timing chart of each part in the direct power output mode. In this embodiment, the dimmer includes a phase control circuit 1, a reactor 2, a current sensor 3, a relay 4, and a control means 5, with an input terminal connected to the AC power source 6. Then, one of the dimming output mode and the direct power output mode is switched as desired to apply the force to the load 7. On the other hand, the load 7 mainly uses an illumination load, for example, an incandescent lamp, in the dimming output mode. In addition, in the direct power output mode, various loads such as the above-described movable lighting apparatus for the production can be connected.

The phase control circuit 1 is inserted into an AC power supply line 8 from the AC power supply 6 to the load 5 and includes a thyristor. As for the thyristor, the pair 1a, 1b is anti-parallel connected. In addition, SCR is used as the thyristors 1a and 1b.

The reactor 2 is connected in series at the phase control circuit 1 and its output end side.

The current sensor 3 is a means which monitors at least the output current of the phase control circuit 1 which flows through the alternating current power supply line 8, and controls and inputs the detection data to the control means 5 mentioned later. In this embodiment, the current transformer is inserted into the AC power supply line 8.

The relay 4 has its contact connected in parallel with the phase control circuit 1. In this embodiment, the parallel circuits of the phase control circuit 1 and the reactor 2 are connected in parallel. Then, the ON and OFF of the relay 4 are controlled by the control means 5 described later.

The control means 5 is comprised mainly by a micon, switches a dimming output mode and a direct power output mode, and performs necessary control according to each mode. In addition, the control means 5 obtains a direct current from the AC power supply 6, and a force is applied, and the detection signal of the output current of the phase control circuit 1 monitored by the current sensor 3 is controlled-input, For the necessary control, calculation is performed to generate various control signals to control the phase control circuit 1 and the relay 4.

Hereinafter, the control operation will be described with reference to FIG. 2. In the figure, (a) is an output voltage waveform of the dimmer, (b) is a load current waveform, (c) is a thyristors gate signal of the phase control circuit 1, and (d) is a control signal of a relay. .

When energizing the load 7 in the direct power output mode, the control means 5 first supplies the gate signal shown in (c) to the phase control circuit 1 at the time point t1 and turns it on. As a result, the output voltage shown in (a) is applied from the phase control circuit 1 to the load 7. At this time, even if the load current shown in (b) becomes the inrush current, the inrush current passes through the phase control circuit 1. Thus, when the load current monitored by the current sensor 3 becomes equal to or less than the predetermined value Ia, the control means 5 supplies the control signal shown in (d) to the relay 4 at the time point t2 and turns it on. . As a result, the phase control circuit 1 is short-circuited and the load current flows to the load 7 via the relay 4, and switching to the direct power output mode is completed.

Next, when stopping the direct power output mode, the control means 5 first stops the supply of the control signal shown in (d) to the relay 4 at time point t3 and turns it off. Next, at the time point t4, the supply of the gate signal shown in (c) to the phase control circuit 1 is stopped to turn it off. As a result, since the phase control circuit 1 is turned OFF with zero cross, the output voltage shown in (a) is lost, and the load current shown in (b) is cut off accordingly, and the direct power output mode stops.

When dimming the load 7 in the dimming output mode, the control means 5 turns off the relay 4 to supply a phase-controlled gate signal to the phase control circuit 1 to phase To control.

3 and 4 show a dimming device as one embodiment for implementing the phase control device of the second invention, FIG. 3 is a circuit diagram and FIG. 4 is a timing chart of each part in the direct power output mode. In addition, the same code | symbol is attached | subjected to the same part as FIG. 1 and FIG. 2, and description is abbreviate | omitted.

In this embodiment, as shown in FIG. 3, the second relay 9 is connected in parallel to the reactor 2, and the control means 5 specifies the second relay 9 with reference to FIG. 4 below. It differs from the form shown in FIG. 1 and FIG. 2 in that it controls so that operation may be carried out with the timing of. In addition, the code | symbol 4 is called a 1st relay, and makes it easy to distinguish from the 2nd relay 9. As shown in FIG.

Next, the control operation will be described with reference to FIG.

When energizing the load 7 in the direct power output mode, the first means 5 first supplies a control signal to the second relay 9, as shown in (e) at time point t01, and the second means. Turn on the relay (9). As a result, the reactor 2 is short-circuited and its impedance does not affect the direct power output circuit.

Next, the gate signal shown in (c) is supplied to the phase control circuit 1, and this is turned ON. As a result, the output voltage shown in (a) is applied from the phase control circuit 1 to the load 7. At this time, even if the load current shown in (b) becomes the inrush current, the inrush current passes through the phase control circuit 1. Thus, when the load current monitored by the current sensor 3 becomes equal to or less than the predetermined value Ia, the control means 5 supplies the control signal shown in (d) to the first relay 4 at the time point t2, and Turn on. After that, the control means 5 stops the control signal for the second relay 9 at time t02 as shown in (e), and turns off the second relay 9. This completes the switching to the direct power output mode.

Next, when stopping the direct power output mode, the control means 5 first stops the supply of the control signal shown in (d) to the first relay 4 at time point t3 and turns it off. Next, at the time point t4, the supply of the gate signal shown in (c) to the phase control circuit 1 is stopped to turn it off. As a result, since the phase control circuit 1 is turned OFF with zero cross, the output voltage shown in (a) is lost, and accordingly, the load current shown in (b) is cut off and the direct power output mode stops.

When dimming the load 7 in the dimming output mode, the control means 5 turns off the first relay 4 and the second relay 9 so that the phase control circuit 1 is phase controlled as required. The gate signal is supplied to perform phase control.

Fig. 5 is a timing chart of each part in the direct power output mode of the dimmer as one embodiment for implementing the phase control device of the third invention. In addition, in this form, a circuit diagram is the same as that of one form in 2nd invention shown in FIG. 4, the same code | symbol is attached | subjected to the same part, and description is abbreviate | omitted.

Next, the control operation will be described with reference to FIGS. 3 and 5.

When energizing the load 7 in the direct power output mode, the control means 5 first supplies a control signal to the second relay 9 as shown in (e) at time point t01, and the second relay. Turn on (9). As a result, the reactor 2 is short-circuited and its impedance does not affect the direct power output circuit.

Next, the gate signal shown by (c) is supplied to the phase control circuit 1 at the time point t1, and this is turned on. As a result, the output voltage shown in (a) is applied from the phase control circuit 1 to the load 7. At this time, even if the load current shown in (b) becomes the inrush current, the inrush current passes through the phase control circuit 1. Thus, when the load current monitored by the current sensor 3 becomes equal to or less than the predetermined value Ia (-Ia), the control means 5 controls the control signal shown in (d) to the first relay 4 at the time point t2. To turn this on. As a result, switching to the direct power output mode is completed, so that the AC voltage can be output directly. On the other hand, in this embodiment, since the phase control circuit 1 and the second relay 9 are controlled as shown in (c) and (e) in the direct power output mode, they are kept in the ON state. .

When stopping the direct power output mode, the control means 5 first stops the supply of the control signal shown in (d) to the first relay 4 at time point t3 and turns it off. Next, at the time point t4, the supply of the gate signal shown in (c) to the phase control circuit 1 is stopped and turned off to zero cross. Finally, as shown in (e), when the second relay 9 is switched to the OFF state at the time t5, the direct power output mode stops. As a result, the output voltage shown in (a) disappears, whereby the load current shown in (b) is cut off, and the direct power output mode stops.

In this way, since the load current is already interrupted as described above when the relay 9 is turned off, the influence of the impedance of the reactor 2 is eliminated and protected even when the direct power output mode is stopped.

When dimming the load 7 in the dimming output mode, the control means 5 turns off the first relay 4 and the second relay 9 so that the phase control circuit 1 is phase controlled as required. The gate signal is supplied to perform phase control.

6 and 7 show one embodiment for implementing the light modulation apparatus of the fourth invention, FIG. 6 is a circuit diagram, and FIG. 7 is a timing chart of each part. In this embodiment, the dimmer includes a first phase control circuit 11, a second phase control circuit 12, a load current detection means 13, and a control means 14, and phases the load 15. It is configured to illuminate the light by controlled alternating current. Incidentally, for example, an incandescent lamp is used for the load 15 as an illumination load.

The first phase control circuit 11 is inserted into an AC power supply line 17 that extends from the AC power supply 16 to the load 15 and includes a self-extinguishing control element. In the self-extinguishing control element, the pairs 11a and 11b are connected in reverse series and the diodes 11c and 11d are connected in reverse parallel as shown in the figure. In addition, an IGBT is used as the self-removal control element 11a.

The second phase control circuit 12 is connected in parallel with the first phase control circuit 11 and includes a thyristor. As for the thyristor, the pair 12a, 12b is anti-parallel connected. In addition, SCR is used as the thyristors 12a and 12b.

The load current detecting means 3 is a means for detecting a load current flowing through the AC power supply line 17. In this embodiment, the current transformer is inserted into the AC line.

The control means 14 is composed mainly of the micon, the direct current is obtained from the AC power supply 16, the force is applied, and the load current detected by the load current detection means 13 is controlled to input the first. The phase control circuit 11 and the second phase control circuit 12 are controlled as described later.

Next, the timing of each control is demonstrated based on the timing chart of FIG. In the figure, (a) is an output voltage waveform, (b) is an output current waveform, (c) is a gate signal waveform of one polarity in the first phase control device, and (d) is similarly the other polarity. The gate signal waveform of (e) shows the gate signal waveform in the second phase control circuit in a manner consistent with time. On the other hand, in FIG. 7, the case where it intends to conduct over electricity is shown.

In other words, when the load 15 is turned on by half-wave conduction, the control means 14 first supplies the gate signal of (c) to the first phase control device 1 at time t1. . As a result, since the self-protection type control element 1a is turned on, the output voltage of (a) and the output current of (b) are started. At this time, since the load 5 is an incandescent lamp, the output current of (b) becomes a rush current and becomes large.

Thus, when the load current exceeds the predetermined value x set in advance at the adjacent time point t2 after the time point t1, the control means 14 starts to supply the gate signal of (e) to the second phase control circuit 12. In addition, the supply of the gate signal of (c) is stopped. By the gate signal of (e), the thyristors 12a and 12b of the second phase control circuit 12 are alternately turned on every half wave of the AC voltage. In addition, the first phase control circuit is stopped by the supply stop of the gate signal of (c). As a result, the output voltage of (a) and the output current of (b) are supplied to the load 15 by flowing over almost all of the AC half-waves via the second phase control circuit 12 in succession to the above starting. The incandescent lamp of the load 15 lights up all of the lights.

Next, when the load current falls below the predetermined value x, the gate signals of (c) and (d) are supplied to the first phase control device 11 after the time point t3. As a result, the self-protection type control elements 11a and 11b alternately turn on, so that the output voltage of (a) and the output current of (b) continuously flow to the load 15. At time t3, the supply of the gate signal of (e) to the second phase control circuit 12 is stopped.

The case where the operation of the phase control device is stopped when the first phase control circuit 11 is operating in a state where the load current is equal to or less than the predetermined value x as described above will be described. At the time point t4 prior to the stop, the gate signal of (e) is supplied to the second phase control circuit 12 and the thyristors 12a and 12b are alternately turned on, and then the gates of (c) and (d) The supply of the signal is stopped to stop the operation of the first phase control circuit 11. At time t5, the supply of the gate signal of (e) to the second phase control circuit 12 is stopped to stop the operation of the second phase control circuit 12. Then, since the load current is cut in the zero cross phase, even if the inductive load is connected, the kickback voltage does not occur at the time of breaking the load current.

In the above operation description, the phase control operation is not mentioned, but is briefly described as follows. That is, in the phase at which conduction starts, the gate signal of (c) or (d) is supplied to the first phase control circuit 11 at a desired phase to start the load current by phase controlled gradient control, so that the load current If the predetermined value is exceeded, the gate signal of (e) is supplied to the second phase control circuit 12 to turn on the thyristors 12a and 12b, so that even if the load is light, phase control without lack of current waveforms can be performed. On the other hand, when the load current falls below the predetermined value x, the first phase control circuit 11 performs the phase control operation. In addition, when the phase control operation is stopped when the first phase control circuit 11 is operating while the load current is lower than or equal to the predetermined value, the second phase control circuit 12 is operated prior to the stop as described above. Then, the operation of the first phase control circuit 11 may be stopped, and then the operation of the second phase control circuit 12 may be stopped.

BRIEF DESCRIPTION OF THE DRAWINGS The circuit diagram of the light control apparatus as one form for implementing the phase control apparatus of 1st invention.

Fig. 2 is a timing chart of each part in the direct power output mode similarly.

FIG. 3 is a circuit diagram of an illuminating device as one embodiment for implementing the phase control device of the second invention. FIG.

4 is a timing chart of each part in the direct power output mode in the same manner.

Fig. 5 is a timing chart of each part in the direct power output mode of the dimming device as one embodiment for implementing the phase control device of the third invention.

Fig. 6 is a circuit diagram of a dimmer device as one embodiment for implementing the dimmer device of the fourth invention.

7 is similarly the timing chart of each part

<Description of the symbols for the main parts of the drawings>

1: phase control circuit 1a, 1b: thyristor

2: reactor 3: current sensor

4: relay 5: control means

6: AC power supply 7: load

8: ac power line 11: first phase control circuit,

11a, 11b: magnetic extinguishing control element 11c, 11d: diode

12 second phase control circuit 12a, 12b thyristor

13 load current detection means 14 control means

15 load 16 AC power

17: AC power line

Claims (4)

A phase control circuit having a thyristor inserted into an AC power line to phase control an AC voltage supplied to a load; A current sensor for monitoring the output current of the phase control circuit; A relay connected in parallel to the phase control circuit to turn on and off an AC voltage; In the direct power output mode, when starting the output, the phase control circuit is turned on at the timing of zero cross of the AC power supply voltage. When the output current of the phase control circuit reaches a predetermined value or less, the relay is turned on and the AC power supply voltage is output. And a control means for turning off the relay and turning off the phase control circuit when the output is stopped. A phase control circuit having a thyristor inserted into an AC power line to phase control an AC voltage supplied to a load; A current sensor for monitoring the output current of the phase control circuit; A reactor inserted into the AC power line and connected in series with the phase control circuit; A first relay connected in parallel to the phase control circuit and the series circuit of the reactor to turn on and off an AC voltage; A second relay connected in parallel to the reactor; In the direct power output mode, when the output is started, the phase control circuit is turned on at the timing of zero cross of the AC power supply voltage after the second relay is turned on, and the output current of the phase control circuit is below a predetermined value. When the first relay is turned on, the second relay is turned off, the AC power supply voltage is output, and when the output is stopped, control means for turning off the first control relay and then turning off the phase control circuit is provided. Device. A phase control circuit having a thyristor inserted into an AC power line to phase control an AC voltage supplied to a load; A current sensor for monitoring the output current of the phase control circuit; A reactor inserted into the AC power line and connected in series with the phase control circuit; A first relay connected in parallel to the phase control circuit and the series circuit of the reactor to turn on and off an AC voltage; A second relay connected in parallel to the reactor; In the direct power output mode, when the output starts, the second relay is turned on, and then the phase control circuit is turned on at the timing of zero cross of the AC power supply voltage. When the output current of the phase control circuit reaches a predetermined value or less, When the first relay is turned on and the AC power supply voltage is output and the output is stopped, the control to turn off the phase control circuit after turning off the first relay while the second relay is on, and then turn off the second relay. A light control apparatus provided with the means. A first phase control circuit having a self-extinguishing control element and inserted into an AC power supply line to phase control the AC voltage; A second phase control circuit having a thyristor and connected in parallel with the first phase control circuit to phase control the AC voltage; Load current detecting means for detecting a load current; In order to conduct the electric current between the AC half-waves in cooperation with the load current detecting means, the first phase control circuit is turned on at zero cross timing, and when the output current of a predetermined value or more flows in the first phase control circuit, the second phase is turned on. When the phase control circuit is turned on, the first phase control circuit is turned off, and the load current flowing through the second phase control circuit is less than a predetermined value, the first phase control circuit is turned on and the second phase control circuit is turned off. And a control means for turning off the first phase control circuit and then turning off the second phase control circuit when the output is turned off.

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