JP2008041463A - Phase control device and phase control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phase control device and a phase control method with two wire type and capable of making a light control unit case small in size. <P>SOLUTION: The phase control device 10 is installed in the middle of a main current circuit 12 and wiring of commercial power supply E, a lamp L, and the phase control device 10 is made by two wires. A control part 18 discharges a gate charge of a switching element which the main current flows to switch off the switching element and flows the main current to a gate of the switching element on the reverse phase side and charges the charge. When changed to the next cycle, the switching element on the reverse phase side in which charges are stored in the gate is switched on and the lamp L is lighted. Discharge and its timing are carried out by a gate charge discharge circuit 24 and a discharge timing setting circuit 26. It is not necessary to install a gate starting power supply part and a control by a CPU, thereby, the light control unit case can be made small in size. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a phase control device and a phase control method, and more particularly to a phase control device and a phase control method for dimming a lighting fixture.

  Today, dimmers for dimming light bulbs (lighting fixtures) are installed in facilities such as hotels and studios, and users of the facilities can adjust the brightness of the light bulbs. As dimmers, dimmers that perform phase control of commercial power supplies are widely used, and thyristors are used as switching elements for the control. In particular, a dimmer using a triac that is relatively easy to drive a gate is often used.

However, when dimming is performed using a triac, high-frequency noise and noise in the audible region are generated because the rising at the time of energization in a half cycle of alternating current is steep.
Since this wide-band noise causes an obstacle to radios, televisions, photographing machines, recording machines and the like used in various facilities, a low-noise phase control device has been conventionally demanded.

  The use of a large choke coil or a low-pass filter is known as an effective means for suppressing noise in the commercial power supply line. However, the size of the case of the dimmer unit is set to a predetermined size according to the standard, and large components cannot be used for the wiring device.

Therefore, a phase controller or a phase control device that solves the above problems is currently provided (for example, Patent Document 1 and Patent Document 2).
JP-A-11-161346 JP-A-6-222846

  The phase controller of Patent Document 1 includes a main current circuit, a switching circuit in which IGBTs provided in the main current circuit are connected in anti-series, and a control circuit including a CPU that performs drive control of the switching circuit. Phase control is performed by obtaining a gentle waveform at the start of energization in a half cycle of the AC waveform. Thereby, a phase controller capable of effectively reducing noise is provided.

  However, the above-mentioned phase controller requires a power supply circuit for starting up the CPU, and it is necessary to connect the AC power source, the load, and the phase controller with four wires, and there is a disadvantage that the wiring needs to be changed.

The phase control device of Patent Document 2 is formed using a main current circuit, a switching circuit in which MOSFETs provided in the main current circuit are connected in anti-series, a control unit that performs gate control of the switching circuit, and a current transformer. Power supply unit. The phase controller uses a current transformer to form a power supply unit so that the phase control device, the AC power supply, and the load can be connected by two wires.
The control unit includes a transistor, and controls the power supplied from the AC power source to the load by controlling the gate voltage for driving the MOSFET by turning the transistor on and off in a cycle synchronized with the AC power source. This suppresses radio noise.

  However, when the current transformer is stored in the case of the dimming unit, a large part is used for the wiring device, and there is a drawback that it is difficult to reduce the size of the dimming unit case.

  In order to solve the above-described drawbacks, an object of the present invention is to propose a phase control device and a phase control method that are two-wire and that allow a dimming unit case to be miniaturized.

A phase control device according to the present invention is provided in the middle of a main current circuit, and includes a main current switching circuit including a switching element connected in series and connected in reverse to the main current circuit, and a main current passing through the switching circuit. A main current off control for controlling off by discharging a gate charge of a switching element through which a main current of the main current circuit is energized. A circuit, a gate charge charging circuit for charging the charge by energizing the main current to the gate of the switching element on the opposite phase side simultaneously with the main current off control, and a gate charge for operating the main current off control circuit at a predetermined timing A discharge circuit and a discharge timing setting circuit for determining the timing are provided.
Further, the switching element is an IGBT.

The phase control method of the present invention is provided in the middle of the main current circuit, and includes a main current switching circuit including a switching element connected in series with the main current circuit, and a main current passing through the switching circuit. And a control unit configured to control a current, wherein the control unit controls to turn off a switching element through which the main current of the main current circuit flows, and at the same time, the main current is gated to the switching element on the opposite phase side. The current is charged to charge the battery.
Further, the switching element is an IGBT.

In the phase control device and the phase control method of the present invention, the phase control device is provided in the middle of the main current circuit. As a result, the phase control device, the AC power source, and the load can be connected by two wires, so that no wiring change is necessary.
In the present invention, charge is stored in the gate of the switching element on the opposite phase side by the main current flowing through the main current circuit simultaneously with dimming, and the switching element on the opposite phase side is turned on in the next half cycle. The power supply unit using the is not necessary, and the dimmer unit case can be downsized. Further, since the phase control by the CPU or the like is not used unlike the prior art, the circuit can be simplified. As a result, the dimmer unit case can be reduced in size, and an inexpensive dimmer can be provided.
The present invention performs reverse phase control using a main current switching circuit composed of switching elements connected in series and reversely connected. Thereby, high frequency noise and noise in the audible region are reduced, and a low noise phase control device can be provided. Further, since the noise can be reduced without using a noise suppressing choke coil or the like, the dimmer unit case can be downsized.

  The present invention achieves low noise phase control while solving the disadvantages of the prior art that require wiring changes or the use of large wiring fixture parts.

A phase control device of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a dimmer using the phase control device of the present invention. FIG. 2 is an embodiment of the dimmer of FIG.
As shown in FIG. 1, the phase control device 10 of the present invention is provided in the middle of the wiring between the commercial power source (AC power source) E and the light bulb (load) L of the main current circuit 12, that is, in the middle of the main current circuit 12. The dimmer 14 of FIG. 1 performs the connection of the phase control device 10, the commercial power source E, and the light bulb L with two wires. Further, the phase control device 10 includes a main current switching circuit 16 including a switching element connected in reverse to the main current circuit 12 and a control unit 18 that controls the main current supplied to the switching circuit 16. It is configured.
As shown in FIG. 2, the main current switching circuit 16 includes a series-reversely connected switching element connected to the main current circuit 12.
The control unit 18 supplies the main current to the gate of the switching element on the opposite phase side when the main current is turned off, and the main current off control circuit 20 that controls the main current flowing through the main current switching circuit 16 by the switching element. A gate charge charging circuit 22 for charging the charge, a gate charge discharging circuit 24 for discharging the gate charge of the switching element at a predetermined timing, and a discharge timing setting circuit 26 for determining the timing for discharging the gate charge of the switching element. Is.

Hereinafter, the phase control device of the present invention will be described in detail based on the circuit diagram of the dimmer shown in FIG.
In the middle of the main current circuit 12, a phase control device 10 is provided, and the commercial power source E, the light bulb (load) L, and the phase control device 10 are connected by two wires.

The main current switching circuit 16 is a circuit composed of switching elements IGBTs Q1 and Q2 with built-in flywheel diodes D1 and D2 connected in reverse to the main current circuit 12.
The main current switching circuit 16 is in a state where a predetermined charge is stored in the gate of the IGBT Q1, and when the positive side of the AC waveform is applied to the collector side of the IGBT Q1, the collector-emitter is turned on and reversely connected in series. The current flows to the light bulb L through the diode D2 of the IGBT Q2 on the opposite phase side, and the light bulb L is turned on. Further, when the gate charge of the IGBT Q1 is discharged while a current is flowing through the light bulb L, the collector-emitter between the IGBT Q1 is turned off, and the power supply to the light bulb L is stopped.
On the other hand, in a state where a predetermined charge is stored in the gate of the IGBT Q2, when the positive side of the AC waveform is applied to the collector side of the IGBT Q2, the collector-emitter is turned on, and a current is supplied to the light bulb L through the diode D1 of the IGBT Q1. The light bulb L is turned on. Further, when the gate charge of the IGBT Q2 is discharged, energization to the light bulb L is stopped.

In the control unit 18, the main current off control circuit 20 includes an NPN type switching transistor Tr1, an IGBT Q1 side off control circuit comprising a resistor R2 connected between the collector of the transistor Tr1 and the gate of the IGBT Q1, and an NPN type switching transistor Tr2. The IGBT Q2 side off control circuit is composed of a resistor R3 connected between the collector of the transistor Tr2 and the gate of the IGBT Q2.
When the transistor Tr1 of the IGBT Q1 side off control circuit is turned on at the dimming timing set by the discharge timing setting circuit 26 to be described later, the charge of the gate of the IGBT Q1 is discharged through the resistor R2, and the light bulb L is not energized. Stopped. Further, when the transistor Tr2 of the IGBT Q2 side off control circuit is turned on, the charge of the gate of the IGBT Q2 is discharged through the resistor R3, and energization to the light bulb L is stopped.

The gate charge charging circuit 22 includes an IGBT Q2 side charging circuit including a resistor R1, a rectifying diode D3, and a resistor R3 for energizing a part of the main current of the main current circuit 12 to the gate of the IGBT Q2, and the main current circuit 12 The IGBT Q1 side charging circuit including a resistor R4, a rectifying diode D4, and a resistor R2 for energizing a part of the main current of the IGBT Q1 to the gate of the IGBT Q1.
The IGBT Q2 side charging circuit energizes a part of the main current to the gate of the anti-phase side IGBT Q2 at the same time when the main current energized to the IGBT Q1 is turned off at the dimming timing set by the discharge timing setting circuit 26. Then, the electric charge is charged up to a specified value voltage of the IGBT Q2. Similarly, the IGBT Q1 side charging circuit charges the gate of the reverse phase side IGBTQ1 to the specified voltage when the IGBTQ2 is turned off.

The gate charge discharge circuit 24 includes a rectifier diode D5, NPN type switching transistors Tr3, Tr4, IGBTQ1 side discharge circuit comprising resistors R5, R6, R7, a rectifier diode D6, NPN type switching transistors Tr5, Tr6, resistors R8, R9, It is a circuit comprised from the IGBTQ2 side discharge circuit which consists of R10.
In the IGBT Q1 side discharge circuit, the emitter of the transistor Tr3 and the collector of the transistor Tr4 are connected, and the emitter of the transistor Tr4 is connected to the base of the transistor Tr1. In the IGBT Q2 side discharge circuit, the emitter of the transistor Tr6 and the collector of the transistor Tr5 are connected, and the emitter of the transistor Tr5 is connected to the base of the transistor Tr2.

The discharge timing setting circuit 26 includes an NPN switching transistor Tr7, a PNP switching transistor Tr8, resistors R11, R12, R13, R14, and R15, a variable resistor VR1 for adjusting the brightness (dimming) of the light bulb L, capacitors C1 and C2, This is a programmable unijunction circuit (a circuit that can set the timing for discharging gate charge in a programmable manner) composed of rectifier diodes D7 and D8.
In the discharge timing setting circuit 26, the collector of the transistor Tr8 and the base of the transistor Tr7 are connected. The discharge timing setting circuit 26 is set so that the collector current flows at a timing when the base voltage becomes lower than the emitter voltage by constantly comparing the emitter voltage and the base voltage of the transistor Tr8. That is, by turning on both of the transistors Tr8 and Tr7, a current flows through the resistor R13, and the dimming timing can be determined. The dimming timing is changed by changing the variable resistor VR1.
The diode D7 is provided to prevent the charge charged in the capacitor C2 from being discharged, and the diode D8 is provided for the emitter-base reverse voltage protection of the transistor Tr8.

Here, the operation of the gate charge discharging circuit 24 will be described.
The base of the transistor Tr4 and the base of the transistor Tr5 of the gate charge discharge circuit 24 are connected by a wiring (conductive wire) 28. The wiring (conductive wire) 28 is connected to a wiring (conductive wire) 30 through which a current flowing through the emitter resistor R13 of the transistor Tr7 of the discharge timing setting circuit 26 is energized. Therefore, when a current flows through the emitter resistor R13, the current flows simultaneously to the bases of both the transistors Tr4 and Tr5 of the gate charge discharge circuit 24 through the wirings 30 and 28, and a signal enters the bases of the transistors Tr4 and Tr5.
If the collector-emitter voltage of the IGBT Q1 is turned on when the AC waveform on the power supply side L1 of the commercial power supply E is positive, the collector-emitter voltage (forward voltage: about 0.7 V) is generated by the resistors R5 and R6. This is divided and becomes the base voltage of the transistor Tr3.
Further, a voltage charged in the capacitor C1 of the discharge timing setting circuit 26 is applied to the collector of the transistor Tr3. At this time, when a signal enters the base of the transistor Tr4, both the transistors Tr3 and Tr4 are turned on. When both the transistors Tr3 and Tr4 are turned on, a current flows through the base of the transistor Tr1, the transistor Tr1 is turned on, and the gate charge of the IGBT Q1 is discharged through the resistor R2. That is, the IGBT Q1 is turned off.
On the other hand, when a signal enters the base of the transistor Tr4, a signal also enters the base of the transistor Tr5. However, when the power source side L1 of the commercial power source E is positive, the ground side L2 of the commercial power source E is negative. Therefore, even if a signal enters the base of the transistor Tr5, the transistors Tr5 and Tr6 are not turned on.
As described above, when a current flows through the emitter resistor R13 of the transistor Tr7, it flows into both the bases of the transistors Tr4 and Tr5, but only the gate charge of the dimming IGBT Q1 or Q2 can be discharged. That is, the gate charge discharge circuit 24 also operates as a positive / negative determination circuit that determines whether L1 and L2 are positive or negative.

Next, the operation of the dimmer circuit will be described.
When the power source side L1 of the commercial power source E is positive, the main current flows from the power source side L1 of the commercial power source E to the light bulb L, resistor R1, diodes D5 and D7, resistor R14, capacitor C2 and resistor R15, and diode D2 of IGBT Q2. Then, it flows to the power source side L2 of the commercial power source E, and the capacitor C2 is charged. When the ground side L2 of the commercial power source E is positive, the main current is commercialized from the ground side L2 of the commercial power source E via the resistor R4, the diodes D6 and D7, the resistor R14, the capacitor C2 and the resistor R15, and the diode D1 of the IGBT Q1. It flows to the power supply side L1 of the power supply E, and the capacitor C2 is charged. That is, the main current that has passed through the diodes D5 and D6 becomes a full-wave rectified DC power supply with pulsating current, and the capacitor C2 is charged with the full-wave rectified voltage.

Further, when the power source side L1 of the commercial power source E is positive, the main current flows from the power source side L1 of the commercial power source E to the gate of the IGBT Q2 through the light bulb L, the resistor R1, the diode D3, and the resistor R3. At this time, the gate voltage is charged to the gate of the IGBT Q2 at a voltage limited to the specified voltage of the IGBT Q2 by the Zener diode ZD2. In addition, since the reverse voltage is applied between the collector and the emitter of the IGBT Q2, the IGBT Q2 is not turned on even when the gate of the IGBT Q2 is charged.
On the other hand, when the ground side L2 of the commercial power source E is positive, the main current flows from the ground side L2 of the commercial power source E to the gate of the IGBT Q1 via the resistor R4, the diode D4, and the resistor R2. At this time, the gate voltage is charged to the gate of the IGBT Q1 at a voltage limited to the specified voltage of the IGBT Q1 by the Zener diode ZD1. In addition, since the reverse voltage is applied between the collector and the emitter of IGBT Q1, IGBT Q1 is not turned on even if the gate of IGBT Q1 is charged.

In the state where the gate charge of the IGBT Q2 is charged at the specified voltage, when the AC waveform changes to the next cycle and the ground side L2 of the commercial power source E becomes positive, the collector-emitter of the IGBT Q2 is turned on, From the ground side L2 of the commercial power source E to the IGBT Q2, the diode D1, the light bulb L, and the power source side L1 of the commercial power source E, the light bulb L is turned on.
In addition, when the AC waveform changes to the next cycle and the power supply side L1 of the commercial power supply E becomes positive while the gate charge of the IGBT Q1 is charged with the specified voltage, the collector-emitter of the IGBT Q1 is turned on. Then, it flows from the power source side L1 of the commercial power source E to the light bulb L, IGBT Q1, diode D2, and the ground side L2 of the commercial power source E, and the light bulb L is turned on.

In the present invention, the dimming timing is determined at the timing when the transistors Tr7 and Tr8 of the discharge timing setting circuit 26 are turned on.
For example, when the bulb Q is turned on while the collector-emitter of the IGBT Q1 is on, the collector-emitter voltage (forward voltage of about 0.7 V) of the IGBT Q1 is the resistance R1, the diode D5, and the resistance R12. A forward voltage of about 0.7 V is applied to the base of the transistor Tr8 via At this time, since the voltage charged in the capacitor C1 is higher than the base voltage of the transistor Tr8, the charge in the capacitor C1 is discharged. When the base voltage of the transistor Tr8 decreases and drops below the emitter voltage due to the discharge of the capacitor C1, both the transistors Tr8 and Tr7 are turned on. When the transistors Tr8 and Tr7 are both turned on, a current flows through the emitter resistor R13 of the transistor Tr7. 3A shows the emitter voltage waveform of the transistor Tr8, FIG. 3B shows the base voltage waveform of the transistor Tr8, and FIG. 3C shows the emitter voltage waveform of the transistor Tr7.

When a current flows through the emitter resistor R13, the IGBT Q1 can be turned off at a certain point in a half cycle by the gate charge discharge circuit 24 (IGBTQ1 side discharge circuit) and the main current off control circuit 20 (IGBTQ1 side off control circuit). . Simultaneously with the turn-off of the IGBT Q1, the main charge of the main current circuit 12 is supplied to the gate of the IGBT Q2 by the gate charge charging circuit 24 (IGBTQ1-side charging circuit), and the charge can be charged. The light bulb L can be dimmed. 4A is a voltage waveform between the emitter and the collector of the IGBT Q1 at 90 degrees dimming, FIG. 4B is an emitter voltage waveform of the transistor Tr7, and FIG. It is a voltage waveform across the bulb L at 90 degrees. The IGBT Q1 is turned off when the emitter voltage waveform (whisker-like pulse) of the transistor Tr7 in FIG. 4B is generated, and the gate of the IGBT Q2 is charged with the voltage in FIG.
The timing of dimming is determined by the discharge time of the capacitor C1. The set value of the discharge time of the capacitor C1 can be determined by the variable resistor VR1 and the resistor R11 connected in parallel to the capacitor C1.

As described above, by discharging the charge stored in the gate of the switching element at the timing of dimming, energization of the light bulb L can be stopped halfway through the cycle. At the same time, the main current, which has been de-energized halfway, is energized to the gate of the switching element on the opposite phase side to charge the charge, so that the switching element on the opposite phase side is turned on when the next half cycle starts. can do. Dimming is possible by repeating this operation every half cycle.
Therefore, there is no need to provide a power supply unit using a current transformer as in the prior art, and the dimming unit case can be downsized. Further, phase control by a CPU or the like is not necessary, and the phase control device 10, the commercial power source E, and the light bulb L can be connected by two lines.

  According to the experiment of the present embodiment, when the charge was stored at the gate specified value voltage of 15 V of the IGBT Q1 or Q2, the collector-emitter of the IGBT Q1 or Q2 could be turned on with the specified voltage. Further, dimming of 500 W was possible.

  The phase control device and the phase control method of the present invention are not limited to a light control device, but are a phase control device and a phase control method that are also effective as a rotational speed regulator such as a ventilation fan or a fan.

It is a block diagram of a dimmer using a phase control device of the present invention. FIG. 2 is a circuit diagram of the dimmer of FIG. 1. 3A shows the emitter voltage waveform of the transistor Tr8, FIG. 3B shows the base voltage waveform of the transistor Tr8, and FIG. 3C shows the emitter voltage waveform of the transistor Tr7. 4A shows the emitter-collector voltage waveform of the IGBT Q1 when the dimming is 90 degrees, FIG. 4B is the emitter voltage waveform of the transistor Tr7, and FIG. 4C is the dimming 90 degrees. It is the voltage waveform of both ends of the light bulb L.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Phase control apparatus 12 Main current circuit 16 Main current switching circuit 18 Control part 20 Main current OFF control circuit 22 Gate charge charge circuit 24 Gate charge discharge circuit 26 Discharge timing setting circuit Q1, Q2 Switching element

Claims (4)

A main current switching circuit which is provided in the middle of the main current circuit and includes a switching element connected in series to the main current circuit and connected to the main current circuit, and a control unit which controls the main current passing through the switching circuit. A phase control device comprising:
The control unit includes: a main current off control circuit that performs off control by discharging a gate charge of a switching element through which a main current of the main current circuit is energized; A gate charge charging circuit for energizing the gate of the switching element to charge the charge; a gate charge discharging circuit for operating the main current off control circuit at a predetermined timing; and a discharge timing setting circuit for determining the timing. A characteristic phase control device. The phase control apparatus according to claim 1, wherein the switching element is an IGBT. A main current switching circuit which is provided in the middle of the main current circuit and includes a switching element connected in series to the main current circuit and connected to the main current circuit, and a control unit which controls the main current passing through the switching circuit. In the configured phase control device,
A phase control method, wherein the control unit performs off control of a switching element through which a main current of the main current circuit flows, and at the same time, supplies the main current to the gate of the switching element on the opposite phase side to charge the charge. The phase control method according to claim 3, wherein the switching element is an IGBT.

Images