KR100628622B1 - Power control apparatus - Google Patents

Abstract

Provided is a power control device which prevents occurrence of flicker in brightness due to a failure of a thyristor at light load.

The dimmer has a first phase control circuit PC1 having self-excited control elements Q1, Q2, a second phase control circuit PC2 having thyristors T1, T2, and an AC voltage half wave. The second phase control circuit is operated when the self-extinguishing control elements Q1 and Q2 of the first phase control circuit PC1 are operated by the inclination control at a desired phase of ripple, and then the conduction is almost saturated. The self-protecting control element is supplied to the thyristors T1 and T2 of the PC2 for a short time that is continuous for the firing time, and before the end of the AC voltage half-wave, at least the reset time is secured and terminated. And control means CC configured to turn on Q1 and Q2.

Description

Power control apparatus

1 is a circuit block diagram showing a first embodiment of a light control apparatus according to the power control apparatus of the present invention.

2 is a voltage and current waveform diagram illustrating the operation timing of each unit in the same manner.

Fig. 3 is a voltage and current waveform diagram illustrating the operation timing of each unit showing the second embodiment of the dimmer according to the power control device of the present invention.

4 is a circuit block diagram showing a third embodiment of the light control apparatus according to the power control apparatus of the present invention.

5 is a voltage and current waveform diagram illustrating the operation timing of each unit in the same manner.

6 is a chart diagram showing the operation flow of the phase control circuit in the same manner.

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

AS: AC Power CC: Control Means

DM: Dimmer IL: Load

l1, l2: AC power line PC1: First phase control circuit

PC2: 2nd phase control circuit Q1, Q2: Self-extinguishing type control element

T1, T2: thyristor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power control apparatus having a first phase control circuit having a self-extinguishing control element and a second phase control circuit having a thyristor.

The first phase control circuit having the self-extinguishing type control element and the second phase control circuit having the thyristor are connected in parallel to intervene in series between the AC power supply and the load, and the first phase has a desired phase of the AC voltage half wave. The self-extinguishing control element of the control circuit is operated by tilt control, and when the conduction is almost saturated, the trigger signal is supplied to the thyristor of the second phase control circuit and the signal is fired. Power control devices such as light control devices configured to perform control are already known (see, for example, claims 5 and 12 of Patent Document 1).

According to Patent Document 1, since the inclination control is performed at the start of the rank-up control, the generation of acoustic noise from a load or a reactor inserted in series into the load circuit is suppressed, and the resistance is relatively small after the inclination control. Since the load current mainly flows through the thyristor side by turning on the thyristor, the heat generation of the light control device is reduced.

[Patent Document 1]

Japanese Unexamined Patent Publication No. 6-338395

In the prior art described in Patent Literature 1, in the case of a light load, since the trigger current does not flow enough for the thyristor to fire, the thyristor may not be turned on. It is configured to continue.

By the way, in the said prior art, even if the polarity of an alternating voltage is reversed and becomes the next half wave, the thyristor may continue to turn on, and there exists a problem that the brightness flickers in a load at this time. . On the other hand, when a dummy resistor is connected in parallel with a load as already known, the thyristor can be reliably turned on at light loads without supplying a trigger signal which continues to the end of the AC voltage half-wave as described above. However, this configuration has a problem that the power loss increases and the cost increases.

It is an object of the present invention to provide a power control device which prevents occurrence of flicker in brightness due to a failure of a thyristor at light loads.

The power control device of claim 1 further comprises: a first phase control circuit having a self-extinguishing control element inserted into an AC power supply line for phase controlling the AC voltage; A second phase control circuit having a thyristor inserted into the AC power line to control the phase of the AC voltage; The firing time is required for the thyristor of the second phase control circuit when the self-protection type control element of the first phase control circuit is operated by the inclination control at a desired phase of the AC voltage half wave, and then the conduction is almost saturated. And a control means configured to supply a short-time trigger signal which at least ensures a reset time and terminates before the end of the AC voltage half-wave, and turns on the self-protection type control element. It features.

In this invention and each following invention, the definition and technical meaning of a term are as follows unless there is particular notice. The power control apparatus of the present invention relates to a configuration of a so-called dimming unit of a power circuit portion having a phase control circuit and a control means for directly controlling the same, and is actually used by adding a dimming control circuit portion for producing illumination. There are many cases. However, the present invention is not limited only to this combination.

<First Phase Control Circuit>

The first phase control circuit is provided with a self-extinguishing control element, and is controlled by the control means described below to start phase control by rank-phase control to a desired phase of an AC voltage half wave. As the self-extinguishing control element, for example, an Insulated Gate Bipolar Transistor (IGBT), a MOSFET, an SIT, or the like can be used. In order to control the ranking, the so-called inclination control, that is, the linear on operation, in which the increase of the current is increased obliquely, is performed.

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 them can be used.

<2nd phase control circuit>

The second phase control circuit is provided with a thyristor which is inserted into an AC power supply line and is on-operated controlled by the control means described later in the first phase control circuit in the desired phase of the AC voltage half wave. In addition, the circuit configuration for phase-controlling an AC power supply voltage is not limited to a specific circuit.

Typically, a configuration in which a pair of thyristors are connected in parallel and in parallel can be used.

<About control means>

The control means cooperatively control the first and second phase control circuits as described below. That is, in the desired phase of the AC voltage half-wave, firstly, the first phase control circuit is operated by tilt control of the self-protection type control element, and then, when the conduction, that is, the load current is almost saturated, the second phase. The short-time trigger signal is supplied to the thyristor of the control circuit to perform the phase control operation. In addition, in the present invention, the "short-time trigger signal" is a time required for continuation of the thyristor by the time required for the thyristor to fire, but before the end of the AC voltage half-wave, the time required from when the trigger signal is stopped until the thyristor starts up. It refers to a trigger signal with a relatively short duration that can at least secure an in reset time.

In addition, the control means supplies a short-time trigger signal to the thyristor, and at least at this time, turns on the self-extinguishing control element.

According to the above configuration of the control means, the first phase control circuit may be turned off while the short time trigger signal of the thyristor is supplied, and may be turned on almost simultaneously with the end of the short time trigger signal. Alternatively, it may be turned on continuously while the thyristor short-time trigger signal is supplied following the tilt control. This is because the self-extinguishing control element can control the thyristor while it is on because the voltage drop at the time of conduction is larger than the voltage drop of the thyristor.

<The function of this invention>

In the present invention, having the above configuration, the first and second phase control circuits are controlled by the control means to cooperatively operate with each other to perform phase control. That is, in the AC voltage half wave, firstly, the first phase control circuit operates by the inclined operation to start phase control of the load current. In the first phase control circuit, when the conduction of the self-protection type control element, i.e., the load current is almost saturated, a short time trigger signal is supplied from the control means to the thyristor of the second phase control circuit. If the load is small, that is, not a light load, the thyristor turns on when a short time trigger signal is supplied. If the thyristor is turned on, the load current flows in the thyristor of the second phase control circuit in which the voltage drop at the time of conduction is smaller than the voltage drop of the self-protected control element even if the self-protected control element is continuously on.

When the AC voltage half-wave ends and its polarity is reversed, the short-time trigger signal has already terminated, and since the reset time has elapsed, the thyristor automatically turns off more reliably.

When the polarity of the AC voltage is reversed to become the next half wave, the above operation is repeated again in the reverse polarity AC voltage half wave. Thus, phase control of the load, that is, dimming, is performed.

Next, phase control in the case of light load is demonstrated. That is, in such a case, since the supply to the thyristor is a short-time trigger signal, the thyristor does not reach the self-holding current, and thus may not be turned on. However, even in such a case, since the self-extinguishing control element of the first phase control circuit continues to turn on in the inclination control operation or turns on again at the same time as the end of the short-time trigger signal, the self-extinguishing control element performs phase control instead. Do As described above, the voltage drop when the self-removal type control element is on is larger than the voltage drop of the thyristor, but since it is a light load, heat generation is not a problem.

The features of the present invention described above are summarized as follows.

1. Even if the thyristor is not turned on at light loads, phase control is automatically performed instead of the self-extinguishing control element. Therefore, it is possible to prevent the occurrence of flicker in brightness due to the thyristors not turning on.

2. Since the trigger signal is a short time trigger signal, it is possible to prevent the thyristors from continuously turning on during the polarity inversion of the AC voltage. Therefore, it is possible to prevent the occurrence of flicker in brightness due to the continuous on operation of the thyristor.

3. Other Features

(1) A self-protecting control element having a relatively small rated current value can be employed. Since the self-extinguishing type control element only performs phase control instead of when the thyristor is not turned on during the on operation and light load by the inclination control, the load current that the first phase control circuit is in charge can be set small. Therefore, a self-protection type control element having a relatively small rated current value can be employed.

(2) The load does not generate acoustic noise. Inclination control by the self-extinguishing control element of the first phase control circuit causes the load current to rise slowly (di / dt is small), and the load does not generate acoustic noise.

(3) The magnetic extinguishing control element is hard to be damaged. Since the self-extinguishing control element can always be used below the maximum instantaneous allowable current value, the self-extinguishing control element is hardly damaged.

(4) In order to turn on the thyristor at light load, a dummy resistor connected in parallel with the load is unnecessary.

The power control device of the invention of claim 2 further comprises: a first phase control circuit having a self-extinguishing control element inserted into an AC power supply line for phase controlling the AC voltage; A second phase control circuit having a thyristor inserted into the AC power line to control the phase of the AC voltage;

Detection means for directly or indirectly detecting a signal corresponding to the phase controlled output;

When the self-extinguishing control element of the first phase control circuit is operated by the inclination control at a desired phase of the AC voltage half-wave, the trigger signal is supplied to the thyristor of the second phase control circuit when the conduction is almost saturated. When the signal detected by the detecting means is equal to or less than the predetermined value while being supplied, it is characterized by including control means configured to perform phase control only by the first phase control circuit.

<About the first phase control means>

The first phase control means is controlled by the control means described later, and is responsible for the whole phase control when the phase control of the AC voltage rises and at light loads.

<About the second phase control means>

The second phase control means is configured to take charge of the flow of the load current after starting the phase control of the AC voltage, and to not operate at light load.

<Measuring means>

The detection means allow being able to directly or indirectly detect a signal corresponding to a phase controlled output, such as detecting a load current, detecting a dimming signal or an output power. Moreover, even when it is comprised by detecting a load current, the specific means is not limited to a specific structure. For example, a current transformer, a current detector resistor, a semiconductor current detector, or the like can be appropriately used. Moreover, 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 end of a dimming position, and the 1st and 2nd phase control circuit. However, if necessary, a pair of current detection means may be distributed and arranged by connecting them in series to each of the first and second phase control circuits.

<About control means>

The control means controls the first and second phase control circuits respectively as in the invention of claim 1, but the trigger signal supplied to the thyristor of the second phase control circuit is a short time trigger signal as in the invention of claim 1. Although it is preferable, even if it is a trigger signal which continues to near the end of AC voltage half wave like patent document 1, a reset period should be ensured.

The control means operates only the first phase control circuit when the magnitude of the load determined based on the detection data of the detection means is equal to or less than a predetermined value, that is, a light load. Here, the trigger signal for the thyristor may not be supplied, and the second phase control circuit may not be operated. For example, the trigger signal may be supplied to the thyristor, and the operation start voltages of the thyristor and the self-protection control element may be adjusted. By the difference, substantially only the first phase control circuit may be operated. In addition, in order to operate the first phase control circuit, a drive signal to the self-protection type control element is supplied, but the drive signal may be continuously supplied in succession to the inclination control, or the drive signal may be supplied after a short time of continuous time. good. In addition, "when the signal detected by the detection means is below a predetermined value" has a correlation with the magnitude of the load, and the predetermined value can be appropriately set as desired. When the detection means detects the load current, it is relatively practical to set it to 20% or less of the rated current.

In addition, the control means can control the first phase control circuit similarly to the case of light load when the load is other than the light load and when the load is other than the tilt control. However, it is not necessary to operate the first phase control circuit as desired.

<The function of this invention>

According to the present invention, the inclination control is performed by the self-extinguishing control element of the first phase control circuit at the time of starting the phase control by the control means regardless of the degree of load. Since the thyristor of the second phase control circuit is turned on when the conduction is almost saturated, the thyristor is turned on to take charge of the subsequent load current and phase control is performed.

Next, the operation at light load will be described. In other words, when the detection data detected by the detection means is equal to or less than a predetermined value, the thyristor of the second phase control circuit does not operate substantially. At the same time, a drive signal is supplied to the self-removal type control element of the first phase control circuit. As a result, at light load, phase control is performed only by the first phase control circuit. Therefore, it is possible to prevent the occurrence of flickering of brightness due to the failure of the thyristor firing. In addition, as described above, the self-extinguishing control element has a large voltage drop at the time of conduction due to the thyristor, but is a light load, so there is no practical problem due to heat generation.

The features of the present invention described above are summarized as follows.

1. Since the phase control is performed by the first phase control circuit including the self-extinguishing element without turning on the thyristors at light loads, it is possible to prevent the occurrence of the flicker of brightness due to the thyristors not turning on.

2. Since the phase control by the self-extinguishing element of the first phase control circuit is only at light load, there is no practical problem due to heat generation.

3. Other Features

(1) A self-protecting control element having a relatively small rated current value can be employed. Since the self-extinguishing type control element only performs on-state operation by tilt control and phase control at light load, the load current in charge of the first phase control circuit can be set small.

Therefore, it is possible to employ a self-protection type control element having a relatively small rated current value.

(2) The load does not generate acoustic noise. Inclination control by the self-extinguishing control element of the first phase control circuit causes the load current to rise slowly (di / dt is small), and the load does not generate influence noise.

(3) The magnetic extinguishing control element is hard to be damaged. Since the self-extinguishing control element can always be used below the maximum instantaneous allowable current value, the self-extinguishing control element is hardly damaged.

(4) In order to turn on the thyristor at light load, the dummy resistor connected in parallel with the load becomes unnecessary.

Embodiment of the Invention

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings.

1 and 2 show a dimming device as a first embodiment of the power control device of the present invention, FIG. 1 is a circuit block diagram, and FIG. 2 is a voltage and current waveform diagram illustrating the operation timing of each part. to be.

This embodiment corresponds to the invention of claim 1. In Fig. 1, reference numeral AS denotes an AC power supply, DM denotes a dimmer, and IL denotes a load.

AC power source (AS) consists of a commercial AC power supply.

The dimmer DM consists of a first phase control circuit PC1, a second phase control circuit PC2, and a control means CC, and a pair of input terminals extending from an anode of the AC power source AS. Is connected to the AC power source AS through the AC power supply lines l1 and l2 and the load IL.

The first phase control circuit PC1 is provided in series with one of the AC power supply lines l1 and includes a self-protecting control element for phase controlling the AC voltage. In this embodiment, it consists of a pair of self-protection type control elements Q1 and Q2 and a pair of diodes D1 and D2. The pair of self-extinguishing control elements Q1 and Q2 are made of, for example, Insulated Gate Bipolar Transistors (IGBTs), which are reverse polarity to each other and are connected in series to the AC power supply line l1.

In addition, the pair of diodes D1 and D2 are connected in anti-parallel to each of the self-extinguishing control elements Q1 and Q2.

Similarly, the second phase control circuit PC2 is inserted in one AC power supply line l1 in series, and is thus provided with a thyristor for connecting the first phase control circuit PC1 in parallel to phase control the AC voltage. . In this embodiment, it consists of a pair of thyristors T1 and T2. The pair of thyristors T1 and T2 are inversely connected to each other.

The control means CC comprises a microcomputer, is applied and operated from an AC power source AS, and is controlled so that the first and second phase control circuits PC1 and PC2 cooperate with each other. That is, the phase control by the inclination control by the 1st phase control circuit PC1 is performed first with respect to an AC voltage half wave. When the conduction of the self-extinguishing control elements Q1 and Q2, i.e., the load current is almost saturated, a short time trigger signal is supplied to the thyristors T1 and T2 of the second phase control circuit PC2 to supply the thyristors T1 and T2. When turned on, the second phase control circuit PC2 performs phase control in place of the first phase control circuit PC1.

The load IL consists of incandescent bulbs.

Next, with reference to FIG. 2, the circuit operation | movement of the light control apparatus in this embodiment is demonstrated. In Fig. 2, (a) is an AC power voltage waveform, (b) is a drive signal current waveform of a self-protection type control element, (c) is a short time trigger signal current waveform, and (d) is a phase control output voltage waveform. Conceptually.

That is, the first leading edge of the bipolar drive signal current shown in FIG. 2 (b) is placed in the control terminal circuit of the self-removal type control element Q1 in the desired phase of the AC voltage half-wave of the sine wave shown in FIG. Causes the first signal portion A to be inclined to flow, the self extinguishing control element Q1 starts the inclination operation along the inclination of the first signal portion A, so that the load current reaches the degree of the AC power supply AS. In FIG. 1 of the upper pole, the AC power supply line l1, the self-extinguishing control element Q1, the diode D2, the load IL, the AC power supply line l2, and the AC power supply AS in FIG. The path of the lower pole flows in order as the load current increases in order, and the tilting operation at the start of phase control is performed.

When the load current is almost saturated, the control means CC next stops the first signal portion A and simultaneously flows the short-time trigger signal current shown in Fig. 2C to the gate circuit of the thyristor T1. As a result, since the thyristor T1 is turned on this time, the phase control output voltage shown in Fig. 2 (d) is applied to the load IL, so that the load current is set from the first phase control circuit PC1. Instead of the thyristor T1 of the two-phase control circuit PC2, the above-described path flows.

When the short time trigger signal current ends, the thyristor T1 remains on. And the control means CC shows the drive signal electric current of the self-protection type control element Q1 of the 1st phase control circuit PC1, as shown to the 2nd part B of FIG. Since it flows again, the self-protection type control element Q1 turns on again. However, since the voltage drop side of the thyristor T1 connected in parallel to the self-extinguishing control element Q1 is small, the load current does not flow through the self-extinguishing control element Q1.

Therefore, even when the thyristor T1 is not turned on due to the short-time trigger signal current under light load, the self-protection type control element Q1 causes the load current to flow in place of the thyristor T1.

Thus, when the AC voltage is reversed in polarity and a half wave of opposite polarity is applied to the AC power supply lines l1 and l2, this time the self-protecting control element Q2 and the diode D1 of the first phase control circuit PC1 are turned on. The thyristor T2 of the second phase control circuit PC2 is turned on, but operates as described above, as shown in the right half of FIG. As a result, phase control is performed for each half wave of each polarity of the AC voltage.

Fig. 3 is a voltage and current waveform diagram illustrating the operation timing of each unit showing the second embodiment of the dimmer according to the power control device of the present invention. In addition, about the same part as FIG. 2, the same code | symbol is attached | subjected and description is abbreviate | omitted. This embodiment corresponds to the invention of claim 1.

That is, in this embodiment, the 1st part A and the 2nd part B in FIG. 2 of the drive signal current with respect to the self-protection type control element Q1 of the 1st phase control circuit PC1 are continuous. It is different in that it is done. On the other hand, the circuit operation is basically the same as in the first embodiment.

4 and 5 show a third embodiment of the dimming device as a power control device of the present invention, FIG. 1 is a circuit block diagram, and FIG. 2 is a voltage and current waveform diagram illustrating the operation timing of each part. In addition, in each drawing, the same code | symbol is attached | subjected about the same part as FIG. 1 and FIG. 2, and description is abbreviate | omitted. This embodiment corresponds to the invention of claim 2.

That is, in this embodiment, the load current detection means CD is provided as a detection means, and the detection data is controlled-input to the control means CC. The load current detecting means CD is made of a current transformer, and is magnetically coupled to the AC power supply line 11 between the first and second phase control circuits PC1 and PC2 and the load IL. Then, the load current is detected and control inputted to the control means CC described later.

Thus, when the load current is equal to or less than the predetermined value, as shown in the flowchart shown in Fig. 6, the control means CC supplies the trigger signal current to the thyristors T1 and T2 of the second phase control circuit PC2. Stop. For this reason, the phase control is performed in place of the self-protection type control elements Q1 and Q2 of the first phase control circuit PC1.

According to the invention of claim 1, the first phase control circuit including the self-protection type control element, the second phase control circuit with the thyristors, and the self phase control type of the first phase control circuit with the desired phase of AC voltage half wave When the element is operated by the inclination control and the conduction is almost saturated next, at least the reset time is continued for the thyristors of the second phase control circuit by the firing time, and before the end of the AC voltage half-wave. And a control means configured to turn on the self-protection type control element while supplying a short-time trigger signal for ensuring and terminating the circuit, thereby preventing occurrence of brightness flicker due to the firing failure of the thyristor at light load. A power control device can be provided.

According to the invention of claim 2, it comprises: a first phase control circuit having a self-protection type control element inserted into an AC power supply line for phase controlling the AC voltage; A second phase control circuit having a thyristor inserted into the AC power line to control the phase of the AC voltage; Detection means for directly or indirectly detecting a signal corresponding to the phase controlled output; When the self-extinguishing control element of the first phase control circuit is operated by the inclination control at a desired phase of the AC voltage half-wave, the trigger signal is supplied to the thyristor of the second phase control circuit when the conduction is almost saturated. When the signal detected by the detecting means is equal to or less than the predetermined value, the control means is configured to perform phase control only with the first phase control circuit, thereby causing the flicker of brightness due to the failure of the thyristors during light load. It is possible to provide a power control device for preventing this from occurring.

Claims (2)

A first phase control circuit having a self-extinguishing control element inserted into an AC power line for phase controlling the AC voltage; A second phase control circuit having a thyristor inserted into the AC power line to control the phase of the AC voltage; The firing time is required for the thyristor of the second phase control circuit when the self-protection type control element of the first phase control circuit is operated by the inclination control at a desired phase of the AC voltage half wave, and then the conduction is almost saturated. And a control means configured to supply a short-time trigger signal which at least ensures a reset time and terminates before the end of the AC voltage half-wave, and turns on the self-protection type control element. Power control device. A first phase control circuit having a self-extinguishing control element inserted into an AC power line for phase controlling the AC voltage; A second phase control circuit having a thyristor inserted into the AC power line to control the phase of the AC voltage; Detection means for directly or indirectly detecting a signal corresponding to the phase controlled output; When the self-extinguishing control element of the first phase control circuit is operated by the inclination control at a desired phase of the AC voltage half-wave, the trigger signal is supplied to the thyristor of the second phase control circuit when the conduction is almost saturated. And a supply means configured to perform phase control only with the first phase control circuit when the signal detected by the detection means is equal to or less than the predetermined value while being supplied.

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