JP2010027406A - Antiphase controller, and antiphase illumination control system using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the number of part items, to compactify a size and to reduce a cost, in an antiphase controller for illumination-controlling an illumination load, by antiphase-controlling an input voltage from an alternating current source. <P>SOLUTION: This antiphase controller 1 is provided with a rectifier 11 for full-wave rectifying the alternating current voltage V1; an n-type FET 12 interposed between the rectifier 11 and the illumination load 2, and for controlling the continuity of a current flowing in the illumination load 2; a zero-cross detecting part 13 for detecting zero crossing of the full-wave rectified voltage; a dimming control level setting part 14 for setting a dimmming control level of the illumination load 2; and a control part 15 for turning on and off the FET, at the timing of the zero cross, and for turning on and off the FET 12 at a fixed fringe angle, in response to the illumination control level. The illumination load 2 is thereby continuity-controlled in the antiphase control for the alternating current voltage V1 by the one switching element, and consequently, the number of part items is reduced to make the size small and to reduce the cost. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a reverse phase control device that controls power supplied to a load by performing reverse phase control of an AC power supply, and a reverse phase dimming control system using the same.

  Conventionally, in an anti-phase control device, for example, in order to perform dimming control of an illumination load of an incandescent lamp or LED, a switching element connected in series between an AC power source and the illumination load is set at a zero cross point of an AC voltage waveform The power supplied to the lighting load is controlled by turning on and turning off at a constant phase angle.

  This kind of anti-phase control device is equipped with a switching element that controls the conduction with the lighting load for each positive and negative voltage of the half cycle of the AC power supply, and dimming the lighting load by controlling the AC power supply in reverse phase with each switching element An anti-phase control device for controlling is known (for example, see Patent Document 1). A configuration example of this type of anti-phase control device will be described with reference to FIGS. 4 and 5.

  In FIG. 4, an antiphase control device 100 controls two transistors Q1 and Q2 for switching connected in reverse series between an AC power source and a lighting load 101, and controls conduction of these transistors Q1 and Q2. Unit 102. The control unit 102 sends positive and negative dimming control signals to the transistors Q1 and Q2, respectively, corresponding to the positive and negative waveforms of the AC power supply voltage, and switches the transistors Q1 and Q2 to control the lighting load 101. As the transistors Q1 and Q2, a power control switching element such as an insulated gate bipolar transistor (IGBT) or a power MOSFET is used. The transistors Q1 and Q2 are connected in parallel with bypass diodes Da and Db that are turned on when they are in the non-conductive mode, respectively.

  In FIG. 5, the anti-phase control device 100 controls two switching transistors Q1 and Q2 connected in antiparallel between the AC power source and the illumination load 101, and the conduction of these transistors Q1 and Q2, respectively. A first gate control unit 103 and a second gate control unit 104 are provided. These gate controllers 103 and 104 control the lighting load 101 by controlling the lighting load 101 by sending positive and negative dimming control signals to the gates of the transistors Q1 and Q2, respectively, corresponding to the positive and negative waveforms of the AC power supply voltage.

However, in the antiphase control device 100 shown in FIGS. 4 and 5, the transistors Q1 and Q2 that are opposite to each other are switched for each positive and negative voltage of the half cycle of the AC power supply voltage. And two bypass diodes Da and Db are also required. These switching elements are expensive and require a heat dissipation member and a driver circuit for driving the switching elements. For this reason, the circuit scale and the circuit board area are increased, the size is increased, the number of parts is increased, and the cost is increased. In addition, the circuit configuration becomes complicated, such as requiring a gate control unit that outputs positive and negative gate control signals and a positive and negative DC power supply circuit to control switching elements that are opposite to each other.
JP-A-6-203967

  The present invention has been made to solve the above problems, and in an anti-phase control device that performs dimming control of an illumination load by performing anti-phase control on an input voltage from an AC power supply, the number of components is reduced, An object of the present invention is to provide an anti-phase control device that can be reduced in size and cost.

  In order to achieve the above object, the invention of claim 1 includes a rectifier that performs full-wave rectification of an AC power supply voltage, a switching element that is interposed between the rectifier and the load, and controls conduction of a current flowing through the load. The switching element includes an anti-phase controller that turns on at a zero-cross timing of a full-wave rectified voltage and turns off at a constant firing angle.

  According to a second aspect of the present invention, there is provided a light source having a resistive load component, a rectifier that performs full-wave rectification of an AC power supply voltage, and a field effect that is interposed between the rectifier and the light source and controls conduction of current flowing through the light source. A transistor, and an antiphase controller that turns on the field-effect transistor at a zero-cross timing of a full-wave rectified voltage and turns off at a constant firing angle, and a source or drain of the field-effect transistor, The GND levels of the antiphase control units are the same.

  According to the first aspect of the invention, since the switching element is turned on / off after full-wave rectification of the AC power supply, the current conduction to the load can be controlled by one switching element, the number of parts can be reduced, and the size can be reduced. And cost reduction.

  According to the invention of claim 2, since the field effect transistor is turned on / off after full-wave rectification of the AC power supply, the conduction control can be performed with one field effect transistor, and the size and cost can be reduced. When the FET is n-type, its source matches the GND level of the anti-phase control unit, so conduction control can be performed simply by applying a positive control voltage to the gate, and the circuit design of the anti-phase control unit becomes easy. The circuit configuration can be simplified.

  Hereinafter, an antiphase control apparatus (referred to as this apparatus) according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the apparatus 1 includes a rectifier 11 that performs full-wave rectification of a sinusoidal AC power supply voltage (hereinafter referred to as AC power supply) V <b> 1, and a rectifier 11 and an illumination load (load, light source) 2. The field effect transistor (FET) 12 as a switching element that controls the conduction of the current flowing through the illumination load 2, the zero-cross detection unit 13 that detects the zero-cross of the full-wave rectified voltage, and the adjustment of the illumination load 2 The light control level setting part 14 which sets a light level, and the antiphase control part (henceforth a control part) 15 which turns off FET12 at the timing of a zero cross and turns off with a fixed firing angle are provided. The illumination load 2 is connected to the load connection unit 16.

  The illumination load 2 is an illumination lamp that has a resistance load component and is turned on upon receiving power supply as a load of the antiphase control device 1. As the illumination load 2, an incandescent bulb, a fluorescent lamp, a solid light emitting element made of a semiconductor such as an LED or an organic EL, and the like can be used.

  The rectifier 11 includes a diode bridge circuit including four diodes D1 to D4, and full-wave rectifies the input AC voltage V1. An AC voltage V1 is input between the intersection A of the diodes D1 and D2 and the intersection B of the diodes D3 and D4, and the drain of the FET 12 is connected to the intersection C of the diodes D2 and D4. Further, the intersection E of the diodes D1 and D3 and the source of the FET 12 are connected to the load connection portion 16. Further, this diode bridge circuit is less expensive than a switching element such as an FET.

  In the rectifier 11, when the AC voltage V1 is a positive voltage, the FET 12 is turned on, whereby a current flows through the circuits of the diode D2, the FET 12, the illumination load 2, and the diode D3. Similarly, when the AC voltage V1 is a negative voltage, a current flows through the circuits of the diode D4, the FET 12, the illumination load 2, and the diode D1 by turning on the FET 12. By this rectification operation, the output of the rectifier 11 becomes a full-wave rectified voltage V2 and a voltage waveform only in the positive direction.

  The FET 12 performs switching control of the full-wave rectified voltage V2 by the rectifier 11. Here, an n-type FET is used for the positive full-wave rectified voltage V2, and the source of the FET 12 is connected to the common ground line 17 so as to coincide with the GND level of the control unit 15. Therefore, the polarity of the control voltage input from the control unit 15 to the gate of the FET 12 has the same positive polarity as the full-wave rectified voltage V2. In addition, it can also be set as the structure which earth | grounded the drain of FET12, In this case, a gate control voltage waveform is inverted. Further, when each diode connection of the diode bridge circuit of the rectifier 11 is reversed and the full-wave rectified voltage is negative, the gate control voltage is also negative, and, for example, a p-type FET is used. Here, although the switching element is an FET, for example, a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor) capable of flowing a large amount of current, an IGBT, or the like can be used.

  The zero cross detection unit 13 detects a timing at which the input voltage from the AC power supply becomes zero cross, generates a zero cross signal at this timing, and inputs the zero cross signal to the control unit 15. The zero-cross detector 13 includes a switching circuit (not shown) that operates when the input voltage has a sine waveform at the positive voltage and the negative voltage, and detects when the switching operation is switched to detect the zero-cross. The FET 12 is turned on at this zero cross timing.

  The dimming level setting unit 14 sets the dimming rate of the illumination load 2 based on a dimming volume (not shown) or a dimming signal. When the dimming rate is set, the dimming level setting unit 14 sets the dimming level by setting the ON period of the FET 12 based on the specified dimming rate, and the set dimming level is controlled by the control unit. 15

  The control unit 15 includes a CPU and a memory, and controls the entire antiphase control device 1. The control unit 15 generates a PWM (Pulse Width Modulation) signal for phase control based on the dimming level set by the dimming level setting unit 14, and performs switching driving of the FET 12 by the PMW signal. The PWM signal is a pulse signal that is started with the generation timing of the zero cross signal detected by the zero cross detection unit 13 as a trigger. When this pulse signal becomes high (H) or low (L), the FET 12 is turned on / off, Switching driven. Further, the input voltage from the AC power supply is supplied to the illumination load 2 during the conduction period in which the FET 12 is turned on. At this time, the control unit 15 turns on the FET 12 at the high level of the PWM signal that rises in synchronization with the zero cross signal, and turns off the FET 12 at the timing when the PWM signal becomes low, thereby controlling the illumination load 2 in reverse phase. .

  Here, with reference to FIGS. 2A to 2E, the operation of the light control by the control unit 15 will be described. FIG. 2A shows a sine waveform of the AC voltage V1, and this AC voltage V1 is full-wave rectified by the rectifier 11 to become a full-wave rectified voltage V2 shown in FIG. The zero-cross detector 13 detects the zero-cross every half cycle of the AC voltage V1, and generates a zero-cross signal having a pulse waveform as shown in FIG. FIG. 4D shows a PWM signal output from the control unit 15, and when the PWM signal is high, the FET 12 is turned on. Thus, when this PWM signal is applied to the FET 12, the FET 12 is turned on only during the ON period Ta of the PWM signal. FIG. 4E shows the load supply voltage supplied to the illumination load 2 in the on period Ta, and here, the phase angle in the half cycle of the AC voltage V1 corresponding to the on period Ta is represented by the firing angle θ. That is, this load supply voltage shows a voltage waveform applied to the illumination load 2 from the zero cross current on timing t1 to the time t2 when the PWM signal is turned off at the firing angle θ. The on period Ta of the PWM signal is changed by the user changing the dimming rate by the volume or the like, and the lighting load 2 is dimmed and controlled.

  As described above, according to the present embodiment, the FET 12 is turned on / off using the full-wave rectified voltage V2 obtained by full-wave rectifying the AC voltage V1 as a power source, so that the conduction control to the illumination load 2 can be performed by one switching element. In addition, the heat dissipating member for dissipating the switching element and the driver circuit for driving are reduced, and the circuit board area is also reduced. Further, positive and negative gate control voltages are not required, and therefore, two gate control units, positive and negative DC power supply circuits and the like are not required. Therefore, the number of parts can be reduced, and the cost and size can be reduced. In the present embodiment, the load of the anti-phase control device 1 is the lighting load 2, but the load is not limited to the lighting load 2 and may be any load that can be operated with an AC power supply voltage controlled in anti-phase. Further, the anti-phase control device 1 of the present embodiment can be integrated with the illumination load (light source) 2 and configured as an anti-phase dimming control system that performs dimming by anti-phase control.

  Next, a modification according to the first embodiment of the present invention will be described with reference to FIG. FIG. 3 shows a connection configuration between the control unit 15 and the FET 12 in the antiphase control device 1 of the present modification. In this modification, the control unit 15 is configured by a CPU, and a gate driver 18 for amplifying the gate control voltage is connected between the output port of the CPU that outputs a gate control voltage composed of a PWM signal and the gate of the FET 12. It is.

  According to this modification, even when the gate of the FET 12 cannot be directly turned on with a gate control voltage (for example, 3.3 V to 5.0 V) from the CPU, the gate driver 18 can amplify the gate control voltage. It is possible to reliably turn on the FET 12 and control conduction.

  In addition, this invention is not limited to the structure of said each embodiment, A various deformation | transformation is possible in the range which does not change the meaning of invention. In the above embodiment, the rectifier is a single-phase bridge rectifier circuit, but may be formed of two single-phase full-wave rectifier circuits with two diodes.

The block diagram of the anti | reverse | negative phase control apparatus which concerns on the 1st Embodiment of this invention. (A) is a waveform diagram of the input voltage of the device, (b) is a waveform diagram of the full-wave rectified voltage, (c) is a diagram showing the zero-cross signal, (d) is a diagram showing the PWM signal, (e ) Is a diagram showing a load supply voltage controlled by the PWM signal of (d). The figure which shows the connection structure of the control part and FET in the modification of the said 1st Embodiment of this invention. The block diagram of the conventional antiphase control apparatus. The block diagram of the other conventional antiphase control apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antiphase control apparatus 11 Rectifier 12 FET (field effect transistor)
13 Zero Cross Detection Unit 14 Dimming Level Setting Unit 15 Control Unit (Antiphase Control Unit)
16 Load connection 17 Ground line 2 Lighting load (load, light source)
θ firing angle

Claims (2)

A rectifier for full-wave rectification of the AC power supply voltage;
A switching element that is interposed between the rectifier and the load and controls conduction of a current flowing through the load;
The switching element is turned on at the zero-cross timing of the full-wave rectified voltage, and is turned off at a constant firing angle, and
An anti-phase control device comprising: A light source having a resistive load component;
A rectifier for full-wave rectification of the AC power supply voltage;
A field effect transistor that is interposed between the rectifier and the light source and controls conduction of a current flowing through the light source;
The field effect transistor is turned on at a zero-cross timing of a full-wave rectified voltage and has an anti-phase control unit turned off at a constant firing angle,
The antiphase dimming control system characterized in that the source or drain of the field effect transistor and the GND level of the antiphase control unit match.

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