JPH04251573A - Inverter - Google Patents

Abstract

PURPOSE:To reduce power loss and enable restart by applying operation power voltage only for a specified time with a control signal for start so as to start it. CONSTITUTION:When a control signal for start is generated by a signal 6, a receiving circuit 7 applies operating power voltage only for a specified time required for the start of an inverter circuit 2 from a first power circuit 3 to a circuit annexed to an inverter 5. Thereupon, the circuit 5 annexed to the inverter operates and the inverter main circuit 2 starts oscillation. Hereby, the power loss arising at the time of power supply to the circuit annexed to the inverter can be reduced, and a starting signal is sent from the signal to a receiving circuit, whereby restart becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inverter device used as an electronic ballast for lighting fluorescent lamps and the like.

[Conventional technology]

FIG. 3 is a circuit diagram showing the configuration of a conventional inverter device (see Japanese Patent Laid-Open No. 63-297278).

The circuit configuration will be explained below. Commercial AC power supply A
C is connected to diode bridge DB via power switch S1
is connected to the AC input terminal of the

A smoothing capacitor C01 is connected to the DC output terminal of the diode bridge DB. The above is DC power supply 1
It consists of When the power switch S1 is turned on, the AC voltage of the commercial AC power supply AC is full-wave rectified by the diode bridge DB, and a DC power supply voltage is obtained across the capacitor C01.

A series circuit of transistors Tr1 and Tr1 and a series circuit of capacitors C1 and C2 are connected in parallel to the DC power supply 1, and these constitute an inverter main circuit 2.

A load L such as a fluorescent lamp is connected between the connection point of the transistors Tr1 and Tr2 and the connection point of the capacitors C1 and C2.
is connected.

The oscillation circuit A includes NAND gates G1 and G2 and a resistor R2,
It is composed of R3 and capacitor C2, and generates an output signal that is alternately inverted to high and low levels.

This output signal is the transistor Tr3 in the drive circuit B.
, is supplied to the base of Tr4. Transistor Tr
3. The output of Tr4 is connected to drive transformers T2 and T3, respectively.
and transistors Tr1 and T via resistors R5 and R6.
It is added between the base and emitter of r2.

The oscillation circuit A and drive circuit B described above constitute an inverter auxiliary circuit, and control the oscillation operation of the inverter main circuit 2.

The operating power supply voltage VDD of the oscillation circuit A is the commercial AC power supply AC.
From one end (or the positive terminal of diode bridge DB), capacitor C02 is connected via diode D1 and resistor R1.
Obtained by charging.

Further, the operating power supply voltage VCC of the drive circuit B is applied to the capacitor C from one end of the commercial AC power supply AC (or the positive terminal of the diode bridge DB) via the diode D1 and the resistor R7.
After the inverter main circuit 2 starts oscillating, the oscillation output of the inverter main circuit 2 generated at both ends of the load L is connected to the capacitor via the transformer T1, resistor R12, and diode D2. Obtained by charging C03.

The above oscillation circuit A consists of integrated circuit components such as NAND gates G1 and G2, so its power consumption is relatively small, but the drive circuit B has to supply the base current of the transistors Tr1 and Tr2, so the power consumption is Power is relatively large. Therefore, the smoothing capacitor C02 that constitutes the power supply of the oscillation circuit A may have a smaller capacity than the smoothing capacitor C03 that constitutes the power supply of the drive circuit B.

Note that the resistor R7 is a resistor for providing initial starting power to the drive circuit B after the power is turned on, and its resistance value is set larger than that of the resistor R1, so that the power loss in the resistor R1 is extremely small. .

With this configuration, in an inverter device that converts DC power supply voltage into high-frequency voltage, the oscillation circuit A has low power consumption and needs to continue stable oscillation after the power is turned on. The operating power supply voltage is supplied by dividing the voltage, while the drive circuit B consumes a large amount of power and the stability of the power supply voltage is not much of a problem, so it operates by rectifying and smoothing the oscillation output of the inverter main circuit 2. Since the power supply voltage is supplied, it has the advantage of stable oscillation after the power is turned on, and since oscillation circuit A consumes little power, there is no power loss even if the DC power supply voltage is always divided and supplied. It doesn't get bigger.

With the configuration shown in Figure 3 above, it is certainly possible to significantly reduce power loss compared to a configuration that divides the DC power supply voltage and obtains power to be supplied to all inverter attached circuits. It is. However, during the operation of the inverter device,
There is always a loss due to the resistor R1, and this loss cannot be ignored.

This becomes more noticeable when the configuration of the oscillation circuit A becomes more complicated.

An inverter device as shown in FIG. 4 can be cited as a conventional example that compensates for the above-mentioned drawbacks. In this inverter device, the configuration and operation of the inverter main circuit 2, oscillation circuit A, and drive circuit B are the same as those already shown in FIG. Only the configuration of the power supply circuit 9 that applies an operating power supply voltage to the inverter-attached circuit consisting of the drive circuit B will be described.

First, when the power is turned on, since the inverter main circuit 2 is not operating, the operating power supply voltage for the inverter auxiliary circuit cannot be obtained from the transformer T1, and a starting power supply circuit is required. This startup power supply circuit includes diodes D1, D2, resistors R1, R13, transistor Tr1, and capacitor C1.
, C02, and a Zener diode ZD2. The operation will be explained below.

First, by turning on the power switch S1, the base current of the transistor Tr2 flows through the capacitor C5 and the resistor R1.
3, the transistor Tr1 is in the on state only during that time, and the diode D1 and the resistor R1
Capacitor C02 is charged through.

When a sufficient amount of charge is stored in the capacitor C5, the base current of the transistor Tr2 stops flowing, so that the transistor Tr1 is turned off. In this way, charge is stored in the capacitor C02. However, the voltage across the capacitor C02 never becomes higher than the Zener voltage of the Zener diode ZD2.

Now, since sufficient charge has already been stored in the capacitor C02 at this time, the oscillation circuit A has started operating, and the inverter main circuit 2 is operating, so the capacitor C02 is connected to the capacitor C02 from the transformer T1 via the diode D2. is charged and the operation of the inverter main circuit 2 does not stop, power continues to be supplied to the inverter auxiliary circuit consisting of the oscillation circuit A and the drive circuit B.

With this configuration, the operating power supply voltage can be obtained from the resistor R1 for a moment at startup, and thereafter from the inverter main circuit 2, reducing power loss even more than the inverter device shown in Fig. 3. can do.

[Problem to be solved by the invention]

The inverter device shown in FIG.
If the oscillation stops for some reason, there is a problem in that it cannot be restarted using an external signal.

An object of the present invention is to provide an inverter device that can reduce power loss in a power supply circuit that supplies power to an inverter auxiliary circuit, and that can stop and restart oscillation of an inverter main circuit.

[Means to solve the problem]

The inverter device of the present invention includes an inverter main circuit that converts a DC power supply voltage into a high-frequency voltage, and an inverter auxiliary circuit that has a function of controlling the oscillation operation of the inverter main circuit.

Furthermore, first and second power supply circuits are provided for applying an operating power supply voltage to the inverter-attached circuit. The first power supply circuit divides the DC power supply voltage to create an operating power supply voltage for the inverter-attached circuit. The second power supply circuit is
The output voltage of the inverter main circuit is rectified and smoothed to create an operating power supply voltage for the inverter auxiliary circuit, which is then applied to the inverter auxiliary circuit.

Further, a signal device and a receiving circuit are provided to control the oscillation of the inverter main circuit. The signal generator generates a start control signal and a stop control signal for starting and stopping the oscillation operation of the inverter main circuit.

The receiving circuit applies an operating power supply voltage from the first power supply circuit to the inverter auxiliary circuit for a predetermined period of time required for starting the inverter main circuit in response to a starting control signal generated from the signal device. The oscillation control operation of the inverter attached circuit is stopped in response to the control signal.

[Effect]

When a starting control signal is generated from the signal device, the receiving circuit applies the operating power supply voltage from the first power supply circuit to the inverter auxiliary circuit for a predetermined period of time required to start the inverter main circuit, so the inverter auxiliary circuit operates and the inverter auxiliary circuit operates. The main circuit starts oscillating.

When the inverter main circuit starts oscillating, the second power supply circuit generates an operating power supply voltage and applies it to the inverter auxiliary circuit. Even if the supply of operating power supply voltage from the circuit to the inverter auxiliary circuit is stopped, the operation of the inverter auxiliary circuit continues, and therefore the inverter main circuit also continues to oscillate.

Further, when the stop control signal is generated from the signal device, the receiving circuit stops the oscillation control operation of the inverter auxiliary circuit, and therefore also stops the oscillation operation of the inverter main circuit.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 1 and 2. This inverter device, as shown in Figure 1,
An inverter main circuit 2 that converts a DC power supply voltage supplied from a DC power supply 1 into a high-frequency voltage, and an inverter auxiliary circuit 5 that has a function of controlling the oscillation operation of the inverter main circuit 2 are provided.

In addition, a first power supply circuit 3 and a second power supply circuit 4 are connected to each other in order to apply an operating power supply voltage to the inverter attached circuit 5.
has been established. The first power supply circuit 3 has a function of dividing the DC power supply voltage of the DC power supply 1 to create an operating power supply voltage for the inverter attached circuit 5. The second power supply circuit 4 has a function of rectifying and smoothing the output voltage of the inverter main circuit 2 to create an operating power supply voltage for the inverter auxiliary circuit 5 and applying it to the inverter auxiliary circuit 5 .

The first power supply circuit 3 is created by dividing the DC power supply voltage of the DC power supply 1 that supplies power to the inverter main circuit 2 using resistors, and always generates a DC power supply voltage regardless of the operation of the inverter main circuit 2. do. The second power supply circuit 4 is
Step down the output of the inverter main circuit 2 using a transformer, for example,
The DC power supply voltage is created by rectification and smoothing, and the DC power supply voltage is generated only during the operation period of the inverter main circuit 2. To summarize the characteristics of the respective power supply circuits 3 and 4, the first power supply circuit 3 always generates a DC power supply voltage, but when used constantly, power loss due to resistance becomes large. Further, although the second power supply circuit 4 has a small power loss, if the operation of the inverter main circuit 2 is stopped, a DC power supply voltage cannot be obtained.

Further, a signal device 6 and a receiving circuit 7 are provided to control the oscillation of the inverter main circuit 2. The signal device 6 has a function of generating a start control signal and a stop control signal for starting and stopping the oscillation operation of the inverter main circuit 2. The receiving circuit 7 applies an operating power supply voltage from the first power supply circuit 3 to the inverter auxiliary circuit 5 for a predetermined time required for starting the inverter main circuit 2 in response to the starting control signal generated from the signal device 6. It has a function of stopping the oscillation control operation of the inverter-attached circuit 5 in response to a stop control signal generated from the inverter 6.

According to this inverter device, when a starting control signal is generated from the signal device 6, the receiving circuit 7 transmits the operating power supply voltage from the first power supply circuit 3 to the inverter auxiliary circuit 5 for a predetermined time period required for starting the inverter main circuit 2. Since the voltage is applied, the inverter auxiliary circuit 5 operates and the inverter main circuit 2 starts oscillating.

When the inverter main circuit 2 starts oscillating, the second power supply circuit 4 generates an operating power supply voltage to supply the inverter auxiliary circuit 5.
Therefore, even if the supply of operating power supply voltage from the first power supply circuit 3 to the inverter attached circuit 5 stops after a predetermined period of time has elapsed after the generation of the start-up control signal, the operation of the inverter attached circuit 5 will continue. Therefore, the inverter main circuit 2 also continues to oscillate.

Furthermore, when a stop control signal is generated from the signal device, the receiving circuit stops supplying power to the inverter auxiliary circuit 5, or stops supplying the drive signal from the inverter auxiliary circuit 5 to the inverter main circuit 2, etc. , since the oscillation control operation of the inverter auxiliary circuit 5 is stopped, the oscillation operation of the inverter main circuit 2 is also stopped.

Hereinafter, the specific circuit configuration of the inverter device of this embodiment will be explained in detail based on FIG. 2.

The configurations of the DC power supply 1 and the inverter main circuit 2 in this inverter device are the same as those of the conventional example shown in FIG. Further, the configuration of the inverter-attached circuit 5 is also composed of an oscillation circuit A and a drive circuit B, and is the same as that of the conventional example. Therefore, the explanation regarding this point will be omitted.

First, the first power supply circuit 3 includes a Zener diode ZD1
, a diode D1, a resistor R1, and a capacitor C02, and when the power switch S1 is on, a DC power supply voltage is always generated across the capacitor C02. Next, the second power supply circuit 4 includes a transformer T1, a diode D2, and a capacitor C02, and a DC power supply voltage is generated across the capacitor C02 only while the inverter main circuit 2 is operating. The signal device 6 generates a start control signal and a stop control signal for starting and stopping the oscillation operation of the inverter main circuit 2. When the switch S2 is on the a side, the signal generator 6 generates a start control signal and a stop control signal. When is on the b side, it becomes a stop control signal.

The receiving circuit 7 includes resistors R4, R2 to R11, comparator CP1, transistors Tr5 to Tr7, and capacitor C4.
, and a diode D3, and its operation is as follows.

First, the case of starting the oscillation operation will be described. When the switch S2 is on the a side, the voltage VDD is output from the signal device 6.
is output and input to the positive terminal of comparator CP1. The negative terminal of comparator CP1 has a voltage of V
Since the voltage of DD is divided by the resistors R9 and R10, the output of the comparator CP1 becomes high level. Therefore,
Transistor Tr5 via resistor R4 and capacitor C4
A base current flows through the transistor Tr5, and the transistor Tr5 is turned on. However, the ON period is only determined by the values of resistor R4 and capacitor C4. While the transistor Tr5 is on, current flows from the capacitor C02 of the first power supply circuit 3 to the capacitor C03 via the resistor R7, and the oscillation circuit A and drive circuit B of the inverter attached circuit 5 start operating. Note that the transistor T
Since the inverter main circuit 2 starts operating before r5 turns off, the inverter main circuit 2 starts operating with power supplied from the second power supply circuit 4 after the transistor Tr5 is turned off. Further, during this period, the transistors Tr6 and Tr7 are in an off state.

Next, a case will be described in which the oscillation operation is stopped.

When the switch S2 is on the b side, the signal device 6 outputs a voltage of 0V, and the output of the comparator CP1 becomes a low level. Therefore, the charge stored in the capacitor C4 is released via the diode D2, the capacitor C4, the resistor R4, and the comparator CP1. At this time, the transistor Tr5 is always in an off state.

A base current flows through the transistors Tr6 and Tr7 via the resistor R2 and the comparator CP1, and the outputs of the NAND gates G1 and G2 are always at a low level.

By doing so, the transistors Tr3 and Tr4 are always turned off, the drive signals for the transistors Tr1 and Tr2 are stopped, and the oscillation operation of the inverter is stopped.

According to the inverter device of this embodiment, the first power supply circuit 3 divides the DC power supply voltage of the DC power supply 1 to create the operating power supply voltage of the inverter auxiliary circuit 5, and the output voltage of the inverter main circuit 2 is rectified. A second power supply circuit 4 is provided which smooths and creates an operating power supply voltage for the inverter auxiliary circuit 5, and when a starting control signal is generated from the signal device 6, the receiving circuit 7
Therefore, power is supplied from the first power supply circuit 3 to the inverter attached circuit 5 only for a predetermined time, and thereafter power is supplied from the second power supply circuit 4, and when a stop control signal is generated from the signal device 6, the receiving circuit 7 Since the oscillation control operation of the inverter attached circuit 5 is stopped, the first power supply circuit 3
The time required to supply power to the inverter auxiliary circuit 5 from the inverter auxiliary circuit 5 is only short when the inverter main circuit 2 is started, and there is almost no power loss in the first power supply circuit 3 during other periods, and the power supply to the inverter auxiliary circuit 5 is It is possible to reduce the power loss that occurs when Moreover, the power supply to the receiving circuit 7 is not stopped, and there is an effect that the oscillation of the inverter main circuit 2 can be stopped and restarted.

In the above embodiment, the inverter-attached circuit 5 includes only the oscillation circuit A and the drive circuit B, but the oscillation circuit and the drive circuit, for example, control the power supplied to the load L for dimming the discharge lamp. It is perfectly possible to include other control circuits such as an output control circuit, such as a load abnormality detection circuit for detecting abnormalities in the load L such as exhaustion of the emitter of the discharge lamp or broken filament. In short, among the circuits that operate on the DC power supply voltage, all the circuits except the receiving circuit 7 may be included in the inverter-attached circuit.

Further, the inverter device may be of a two-stone type as shown in FIG. 2, or may be of other types such as a one-stone type or a four-stone type.

The signal device 6 that generates the control signal may not only generate a start control signal and a stop control signal for starting and stopping the oscillation operation of the inverter, but may also generate an output control signal. If the load L is a discharge lamp,
For example, a knob is provided on the signal device 6, and by turning this knob to change the switch, all modes of stopping inverter oscillation, starting inverter oscillation, starting discharge lamp (dimming state), and turning on all discharge lamps can be controlled externally. There is no problem with a circuit that can be controlled from anywhere.

〔Effect of the invention〕

According to the inverter device of the present invention, the first power supply circuit divides the DC power supply voltage to create the operating power supply voltage of the inverter auxiliary circuit, and the output voltage of the inverter main circuit is rectified and
A second power supply circuit that smooths and creates an operating power supply voltage for the inverter-attached circuit is provided, and when a starting control signal is generated from the signal device, the receiving circuit transfers the voltage from the first power supply circuit to the inverter-attached circuit for a predetermined period of time. After that, power is supplied from the second power supply circuit, and when a stop control signal is generated from the signal device, the receiving circuit stops the oscillation control operation of the inverter attached circuit. The time required to supply power from the circuit to the inverter auxiliary circuit is very short and only occurs when the inverter main circuit starts up, and there is almost no power loss in the first power supply circuit during other periods, which occurs when power is supplied to the inverter auxiliary circuit. Power loss can be reduced. Furthermore, since the power supply to the receiving circuit continues, sending a starting control signal from the signal device to the receiving circuit has the effect of making it possible to stop oscillation and restart the inverter main circuit.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an inverter device according to an embodiment of the present invention, FIG. 2 is a circuit diagram showing a specific configuration of the inverter device shown in FIG. 1, and FIG. 3 is a block diagram showing the configuration of a conventional inverter device. Circuit Diagram FIG. 4 is a circuit diagram showing the configuration of another conventional inverter device.

Claims (1)

[Claims] An inverter main circuit that converts a DC power supply voltage into a high-frequency voltage, an inverter auxiliary circuit that has a function of controlling the oscillation operation of the inverter main circuit, and an operating power supply voltage for the inverter auxiliary circuit that divides the DC power supply voltage. a first power supply circuit that rectifies and smoothes the output voltage of the inverter main circuit to create an operating power supply voltage for the inverter auxiliary circuit and applies it to the inverter auxiliary circuit; and the inverter main circuit. a signal device that generates a start control signal and a stop control signal for starting and stopping the oscillation operation of the inverter; and a signal device that outputs a start control signal and a stop control signal from the first power supply circuit to the inverter auxiliary circuit in response to the start control signal generated from the signal device. an inverter device comprising: a receiving circuit that applies an operating power supply voltage for a predetermined time required to start up the inverter main circuit and stops the oscillation control operation of the inverter auxiliary circuit in response to a stop control signal generated from the signal device; .