JPH03141598A - Inverter apparatus - Google Patents

Abstract

PURPOSE:To supply operational electrical power of a controlling circuit sufficiently by installing an electric power source circuit for controlling to obtain the whole or a part of the electric power for controlling through a signal supplied from outside through a signal wire. CONSTITUTION:A capacitor C0 is charged by signal voltage of signal wires l3, l4 through a diode D4 and the capacitor C0 supplies operational electric power source of a controlling circuit 13. The signal voltage of the signal wires l3, l4 are separated into those for electric power source and signal through diodes D4, D5 and one is used for electric power source for controlling through the diode D4 and the other is used for signal for controlling through the diode D5. In this way, the whole or a part of the electric power source for controlling is obtained from signal supplied from outside through the signal wires l3, l4 and thus, not like a conventional one, large electric power consumption owing to a resistor for voltage decrease is not caused and wasteful electric power consumption in an inverter apparatus is prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an inverter device whose output is variable based on an external signal, and can be used, for example, in a lamp load dimming system or a motor speed control system. It is something that will be done.

[Prior Art] FIG. 5 shows a conventional example of a four-wire multi-flash simultaneous dimming system. The AC voltage of the AC power supply Vs is supplied to the inverter device 1 via a power line 12. The inverter device 1 includes an inverter lighting circuit 11, a lamp load 12, and a control circuit 13. The inverter lighting circuit 11 converts a DC voltage obtained by rectifying and smoothing the AC voltage of the AC power supply Vs into a high-frequency voltage, and supplies the high-frequency voltage to the lamp load 12 . The control circuit 13 controls the oscillation operation of the inverter lighting circuit 11 according to a dimming signal supplied from the outside, and controls the lamp load 12.
Controls the power supplied to the device and makes the light output variable. The dimming signal output from the external dimming circuit 2 is transmitted through a separately wired signal line 1. ．． The signal is supplied to the control circuit 13 via 14. Power lines fll, b and signal lines 1. ．． 1°, a plurality of inverter devices 1 are connected in parallel, and by changing the dimming signal output from the external dimming circuit 2, the light output of the plurality of lamp loads 12 can be changed simultaneously. .

FIG. 6 is a specific circuit diagram of the inverter device 1 used in such a dimming system. The circuit configuration will be explained below. The AC voltage of the AC power supply Vs is full-wave rectified by the diode bridge DB, smoothed by the capacitor C1, and becomes the DC power supply EI. At both ends of the capacitor C3, there are transistors Q, , Q, which are main switching elements.
series circuits are connected in parallel, and each transistor Q, ,Q,
diodes D + and D 2 are connected in antiparallel to each other. A resonance capacitor C1 is connected to both ends of the transistor Q2 via a coupling capacitor C5 for cutting DC components, a current limiting and resonance inductor, and a current transformer CT for feeding back the load current. A parallel circuit of lamp loads 12 is connected. The lamp load 12 is two discharge lamps A.

B, and a capacitor C3 and a current transformer CT that constitute the filament preheating circuit. The inductor forms an LC resonant circuit together with the capacitors C, , C, and the load current becomes an oscillating current. This oscillating current is the current transformer C
T, flows through the primary winding of T. Therefore, a voltage whose polarity changes depending on the oscillating current flowing through the load is induced in the secondary winding of the current transformer CT, and this induced voltage is applied between the base and emitter of the transistor Q2 via the resistor R2. and switches the transistor Q.

The output signal of the control circuit 13 is supplied to the base of the transistor Q. The control circuit 13 includes a transistor Q
, a drive circuit 13a for driving , and an external dimming circuit 2
It is provided with a conversion circuit 13b that converts a dimming signal made of a rectangular wave voltage supplied from a DC voltage into a DC voltage. Drive circuit 13
In a, the voltage across the transistor Q is detected, and after the voltage across the transistor Q falls, the transistor Q is turned on for a predetermined period of time.

This predetermined time is determined according to the DC voltage output from the conversion circuit 13b.

The inverter lighting circuit 11 includes a starting circuit for starting self-oscillation operation when the DC power source E1 is turned on. This startup circuit is activated by capacitor C2 when the power is turned on.
is charged through the resistor R, and when the charging voltage reaches the breakover voltage of the two-terminal thyristor Q, the two-terminal thyristor Q is turned on, and the base of the transistor Q is connected to the base of the two-terminal thyristor Q. A current is passed through the transistor Q3 to first turn on the transistor Q3 and start the oscillation operation.

The operation of the circuit shown in FIG. 6 will be explained below. When the power is turned on, transistor Q is activated by the startup circuit.

is turned on, and the voltage across it becomes the "Lou+" level. As a result, the drive circuit 13a is triggered and its output becomes "High" level, and the transistor Q,
remains on. When transistor Q is turned on, diode D0 becomes conductive and capacitor C2 is no longer charged, so the starting circuit stops. At this time, the secondary winding of the current transformer CT is wound with a polarity that applies a reverse bias voltage between the base and emitter of the transistor Q2, so the transistor Q2 remains in the OFF state. , after a predetermined period of time has elapsed, the drive circuit 13
The output of a becomes “Low” level, and the transistors Q,
is turned off. When transistor Q is turned off, the collector current of transistor Q decreases, and the residual inductance of inductor L generates an opposite induced voltage, and the oscillating current flowing through the inductor tends to flow in the same direction, so diode D , conducts. Furthermore, the secondary winding of the current transformer CT1 generates a reverse induced voltage, so that the transistor Q2 is forward biased, and the transistor Q2 is turned on. When the current in diode D becomes zero, current flows through transistor Q2 using the accumulated charge in capacitor C5 as a power source.

At this time, the core of the inductor L is linearly magnetized toward the saturation magnetic flux. Eventually, when the core reaches saturation magnetic flux, the inductance rapidly goes toward zero, and as a result, the amount of time change in the collector current of transistor Q2 becomes infinite. When the collector current of the transistor Q2 reaches hfe times the base current, the transistor Q2 becomes unsaturated, the base current fed back from the current transformer CT decreases, and the transistor Q2 turns off. Even after the transistor Q2 is turned off, the oscillating current flowing through the inductor tends to flow in the same direction, so the diode D2 becomes conductive and becomes an inductor, and the lamp load 12 and the capacitor C1
, a diode D2 through which current flows in the path of the DC power source El.
When the transistor Q becomes conductive, the voltage across the transistor Q becomes zero, so the drive circuit 13a is triggered and the drive circuit 1
The output of 3a becomes High” level, and the transistor Q
, is forward biased. After the oscillating current flowing through the diode D2 becomes zero, the DC power supply E1 connects the capacitor C1, the lamp load 12, the inductor, and the transistor Q.
.

Current flows through the path. Thereafter, by repeating the above-described operation, the oscillation operation of the inverter is continued.

As the dimming signal supplied from the external dimming circuit 2 to the conversion circuit 13b, as shown in FIG. 8(a), a signal with a constant period 1+ and a variable on-time t2 is used.

The 81st ffi (b) shows the relationship between the on-duty (t2/l+) of the dimming signal and the optical output. Here, when the on-duty (t2/1l) of the dimming signal is increased, the optical output decreases almost linearly.

FIG. 7 shows details of the drive circuit 13a and the conversion circuit 13b. The conversion circuit 13b is supplied with a dimming signal whose on-duty is variable from the external dimming circuit 2, and controls the output pulse width of the drive circuit 13a. The drive circuit 13a is a general-purpose integrated circuit (for example, NEC μP).
D4538) monostable multivibrator IC,
It is equipped with In this monostable multi-bibreak IC, after the falling trigger input terminal B changes from the "High" level to the "Low" level, the output terminal Q is at the "High" level and the output terminal q is at the "Low" level for a certain period of time. In this embodiment, the voltage across the transistor Q is detected by dividing it with a series circuit of resistors R, , R4, and is used as a trigger signal for the monostable multivibrator IC.The output terminal of the monostable multivibrator IC. Q
is at “High” level (output terminal q is at “Lo
The time it takes for w to reach the level is determined by the resistor R6 and capacitor C,
determined by the time constant of

The output terminal Q is connected to the base of the driving transistor Q4, and the output terminals are connected to the base of the driving transistor Q4. Transistor Q.

The collector of is connected to the positive terminal of the capacitor C0, and the transistor Q
The emitters of , are respectively connected to the negative terminal of the capacitor C0, and the emitters of the transistors Q, and the transistors Q,
The collector of is connected to the base of transistor Q via resistor R9. Therefore, the monostable multivibrator IC operates as a timer circuit for determining the on period of transistor Q3. The output of the operational amplifier C2 is connected to the connection point of the time constant setting resistor R6 of the monostable multivibrator IC and the capacitor C1 via a diode D and a resistor Rt.

The operational amplifier IC2 is a buffer amplifier having an inverting input terminal connected to an output terminal, and outputs the voltage of the capacitor C7 applied to the non-inverting input terminal with low impedance. The output terminal of an operational amplifier IC is connected to the capacitor C1 via a resistor R8. operational amplifier IC,
is a buffer amplifier having an inverting input terminal connected to an output terminal, and outputs a dimming signal applied to a non-inverting input terminal with low impedance. Resistor R8 and capacitor C7
constitutes a CR integration circuit, which converts a dimming signal consisting of a rectangular wave voltage into a DC voltage VCt. This DC voltage vc
, becomes higher as the on-time t2 in the dimming signal becomes longer. The operational amplifier ■C2 receives the above DC voltage ■through the control resistor R1. , is passed in parallel with the resistor R6. Therefore, as the DC voltage VC increases, the charging current of the capacitor C6 increases, the time constant of the monostable multivibrator C2 decreases, and the drive circuit 13
Since the output pulse width of a becomes smaller, the output of the inverter lighting circuit 11 decreases.

In addition, in Figure 6, a circuit for two lamps is used as the lamp load 12, and in Figure 7, a circuit for one lamp is used, but in this dimming system, which circuit is used? Also good.

[Problems to be Solved by the Invention] In the conventional example described above, the control circuit 1
3 operating power source is obtained. Specifically, the operating current of the monostable multivibrator ■c, operational amplifiers IC2 and IC3, and transistors Q = and Qs is expressed by the capacitor C.
I'm getting it from 0. However, since the charging voltage of the capacitor C1 is a high voltage of, for example, about 100 to 200 V, and the charging voltage of the capacitor C0 is a low voltage of, for example, about 10-odd V, power loss in the resistor R0 becomes a problem. In particular, like the simultaneous multi-flash dimming system shown in Figure 5,
When a large number of inverter devices 1 are connected in parallel, the resistor R0 of each inverter device 1 causes wasteful power consumption, so when totaled as a whole, a non-negligible amount of power consumption occurs. Become. Another possible method is to step down the AC voltage from the AC power supply Vs using a dedicated step-down transformer and obtain the operating power for the control circuit 13 using a dedicated rectifying and smoothing circuit, but in this case, the weight and shape of each inverter device 1 will be large. There is a problem with becoming.

The present invention has been made in view of the above points, and its purpose is to efficiently use the operating power source of a control circuit in an inverter device in which the power supplied to the load is varied by a signal supplied from the outside. The goal is to be able to supply it well.

[Means for Solving the Problems] In the present invention, in order to solve the above problems, the first
As shown in Figures to Figure 4, from the AC power supply Vs to the power line 1
．． AC power is supplied through 12, and signal lines are connected from the outside! In an inverter device that can control power supplied to a load according to a signal supplied via the signal line !, all or part of the control power source is connected to the signal line ! A control power supply circuit 14 for obtaining signals supplied from the outside via terminals 1 and 14.
It is characterized by having the following.

[Effect] In the inverter device of the present invention, the power line l.

Unlike the conventional example in which all of the power for control was supplied from AC power supplied through the signal line 12.

! Since all or part of the control power source is obtained from the signal supplied from the outside through , as in the conventional example,
The step-down resistor R0 does not consume a large amount of power, and wasteful power consumption in the inverter device can be prevented.

[Embodiment 1] FIG. 1 is a circuit diagram of an embodiment of the present invention. In this embodiment, in the conventional example shown in FIG. 6, the step-down resistor R0 is omitted, and the diode D, via signal line 13,1
．． The capacitor C0 is charged by the above signal voltage,
The operating power for the control circuit 13 is supplied from this capacitor C0. In addition, signal lines 1, . 1. The above signal is input to the control circuit 13 via the diode D. In other words, signal line 1. ．． The signal voltage on 14 is connected to diode D,
, D, are used for power supply and for signals, and one side is diode D.

The other is used as a control power source via a diode D5, and the other is used as a control signal via a diode D5.

[Example 2] FIG. 2 is a circuit diagram of a second embodiment of the present invention.

In this embodiment, the signal line 1s, 1= is connected to the AC input end of the diode bridge DB2, and the capacitor C0 is connected to the DC output end of the diode bridge DB2, so that the signal line 1ts, 1< The capacitor C0 is charged by the above signal voltage. Also, the - side signal tl
In this embodiment, the signal lines ez and l- are connected to the input end of the conversion circuit 13b to input external signals to the conversion circuit 13b, even if the signal lines ez and l- are connected in reverse. , there is an advantage that a DC voltage of normal polarity can be obtained at the capacitor Co.

Example 3] FIG. 3 is a circuit diagram of a third embodiment of the present invention.

In this embodiment, in the circuit shown in FIG.
A capacitor C0, which serves as a control power source, is connected to the capacitor C0 through a voltage step-down resistor R0.

However, the resistance value of the step-down resistor R0 is set higher than that of the conventional example shown in FIG. For this reason, the resistance R
Although the power consumption at 0 is smaller than that of the conventional example shown in FIG. 6, since the current supplied from capacitor C1 to capacitor C0 is reduced, the power supplied to control circuit 13 is insufficient. Diode D,
Through the signal line 1. ．． f, is supplied from the above square wave voltage. As a result, the control circuit 13 is sufficiently supplied with the power necessary for its operation, and the power consumption in the inverter device 1 is reduced compared to the conventional example shown in FIG.

Example 4 FIG. 4 is a circuit diagram of a fourth embodiment of the present invention.

In this embodiment, a chopper circuit 16 is provided on the input side of the inverter lighting circuit 11. A large number of inverter devices 1 are connected to a power line 1. , t'2, by providing such a chopper circuit 16 in each inverter device 1, the input power factor can be improved, and
Harmonic components of input current can be reduced. chopper circuit 1
As the lamp load 6, any of the step-up type, step-down type, and buck-boost type may be used, but as in this embodiment, the lamp load 1 for two lamps
2, in order to increase the input DC voltage of the inverter lighting circuit 11, it is particularly preferable to use a step-up chopper circuit 16.
At the DC output end of the diode bridge DB,
The inductor is connected through the transistor Q, and the transistor Q.

A smoothing capacitor C1 is connected to both ends of the line via a backflow blocking diode D6. transistor Q
4 is switched at high frequency by the output of the chopper control circuit 15. First, when transistor Q4 is on, the DC current from diode bridge DB flows through transistor Q4 to inductor L+, and energy is stored in inductor L1.
(When the inductor L1 is turned off, the inductor L1 generates a voltage across it, and the voltage obtained by adding the voltage across the DC output terminal of the diode bridge DB and the voltage across the inductor L is applied to the capacitor C1 via the diode D6. As a result, a voltage higher than the voltage at the DC output terminal of the diode bridge DB can be obtained at the capacitor C4.

By the way, when such a step-up chopper circuit 16 is provided, if a method is used in which the capacitor C0 is charged from the capacitor C3 through the step-down resistor R8, as shown in FIG. Power consumption is a particular problem. Therefore, in this embodiment, the signal 11 m! Ko, l
<The above rectangular wave voltage charges the capacitor C0 via the resistor R3 and the diode D, and the chopper control circuit 1
5 operating power source.

Although the method of supplying control power to the control circuit 13 of the inverter lighting circuit 11 is not particularly illustrated, either method shown in FIG. 1 or FIG. 3 may be used.

Note that the signals transmitted through the signal lines 1s and 14 are not limited to rectangular wave voltages, but may also be DC voltages with variable voltage values, or AC voltages with variable amplitudes or frequencies. It may be.

Further, the load of the inverter device is not limited to a lamp load, but may be a motor or other load.

[Effects of the Invention] As described above, the present invention is capable of supplying AC power from an AC power supply via a power line, and controlling the power supplied to a load according to a signal supplied from the outside via a signal line. The inverter device is equipped with a control power supply circuit for obtaining all or part of the control power supply from a signal supplied from the outside via the signal line, so the signal line is more important than the power line. Because it handles low voltage, it has the advantage of being able to supply control power more efficiently than a method that supplies all of the control power from high-voltage AC power supplied via the power line via a step-down resistor. .

Furthermore, compared to the method of supplying control power from AC power through a step-down transformer and a rectifying and smoothing circuit, this method has the effect that the inverter device can be made smaller and lighter.

In addition, in a system where many inverters are connected in parallel to power lines and signal lines, if one high-capacity low-voltage power supply circuit is provided as the signal supply source to the signal lines, each inverter Since a voltage power supply circuit is not required, the overall size and weight can be reduced and power consumption can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a first embodiment of the present invention, Fig. 2 is a main circuit diagram of a second embodiment of the invention, Fig. 3 is a circuit diagram of a third embodiment of the invention, and Fig. 4 is a circuit diagram of a third embodiment of the invention. is a circuit diagram of a fourth embodiment of the present invention, FIG. 5 is a block diagram of a conventional dimming system, FIG. 6 is a circuit diagram of an inverter device used in the above, and FIG. 7 shows details of a control circuit used in the same. FIG. 8(a) is a waveform diagram of a dimming signal used in the same as above, and FIG. 8(b) is a diagram showing the relationship between the dimming signal and optical output in the same as above. Vs is an AC power supply, 1 is an inverter device, 2 is an external dimming circuit, 14 is a control power supply circuit, 1. ．． 12 is a power line; 1.
, (1, is a signal line.

Claims (1)

[Claims] (1) In an inverter device that is supplied with AC power from an AC power source via a power line and is capable of controlling the power supplied to a load according to a signal supplied from the outside via a signal line, all or An inverter device comprising a control power supply circuit that obtains a portion of the signal from a signal supplied from the outside via the signal line.