KR200431006Y1 - Three Wavelength Electrodeless Fluorescent Lamp - Google Patents

Abstract

The present invention relates to driving an electrodeless fluorescent lamp, wherein the electrodeless fluorescent lamp has a circular cross section, is curved in a donut shape, has a bulb filled with an encapsulating gas therein, and a ferrite core and is coupled to the bulb to have a high frequency. Including a high-frequency generator for generating a high frequency is characterized in that it induces ultraviolet light by reacting with the encapsulation gas. As a result, it has excellent efficiency, long life, energy saving, low heat generation, low cooling cost, and high color rendering to produce natural colors. Provide a fluorescent lamp.

Electrodeless, fluorescent lamps, ferrite cores

Description

Three Wavelength Electrodeless Fluorescent Lamp

1 is a perspective view illustrating an electrodeless lamp.

2 is a block diagram of a lighting system according to the present invention.

3 is a block diagram of a lighting system illustrating in detail a high frequency generator according to an embodiment of the present invention.

4 is a view for explaining a driving principle of the electrodeless fluorescent lamp.

FIG. 5 is a diagram for describing the oscillation control circuit of FIG. 3.

FIG. 6 is a diagram for describing the decision circuit of FIG. 5.

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

111: Electromagnetic Interference Filter

112: rectifier 113: PFC (Power Factor Correction) circuit

115: oscillation control circuit 120: electrodeless lamp

121: bulb 122: long side

123: short side 126: ferrite core

The present invention relates to a three-wavelength electrodeless fluorescent lamp, and more specifically, closer to natural colors to reduce eye fatigue, satisfy the needs of consumers in the well-being era, as well as excellent efficiency and long life. An electrodeless fluorescent lamp having a high frequency generator is provided.

Fluorescent lamps pass a current through the filament in the fluorescent lamp through a ballast dedicated to low-pressure discharge lamps, the electrons emitted from the heated filament stimulates mercury to generate ultraviolet rays. At this time, the generated ultraviolet rays stimulate the fluorescent material applied to the inner surface of the glass tube to generate visible light. In contrast, an electrodeless fluorescent lamp is a lamp in which a ferrite core is installed outside the bulb instead of an electrode (filament, light emitting tube) inside a gas-filled bulb, unlike a conventional lamp, and the high frequency switching (250kHz, When energy is supplied from a special inverter (electronic ballast for electrodeless lamps) capable of 2.65MHz), a magnetic field is generated in the lamp to excite the encapsulated gas inside the bulb to emit light. Can be.

These electrodeless fluorescent lamps significantly reduce power consumption and dramatically increase their lifetime. Accordingly, since the heavy metal gas that is discarded can be reduced, the electrodeless fluorescent lamp is in the spotlight as an environmentally friendly light source. As such, the principle of the electrodeless fluorescent lamp was 1907 PC. Proposed by Hewitt, various types of electrodeless fluorescent lamps have been commercialized in recent years. In 1991, Matsushita introduced 'Everlight', an electrodeless fluorescent lamp. Everlight operates at 13.56MHz and has an efficiency of 37.0 lm / W. In 1991, Philips introduced a 'QL' lamp that operates at 2.65MHz and has an efficiency of 65.0 lm / W. In 1994, GE introduced Genura, which operates at 2.65MHz and has an efficiency of 48.0 lm / W. In the same year, Osram announced Endura, which operates at 0.25MHz and has an efficiency of 75.0 lm / W.

However, such conventional electrodeless fluorescent lamps operate at a relatively high frequency, which may cause electromagnetic interference, deteriorate the stability of the driving circuit, and there is still room for improvement in power efficiency.

In addition, it can be said that a unique and unique bulb design is required in response to various consumer needs. Therefore, research on electrodeless fluorescent lamps with superior design, long lifetime, high efficiency, and high color rendering are urgently needed.

In addition, since the existing discharge lamp has a problem such as energy consumption and room temperature rise by emitting a high heat amount, it can be said that a new lamp that can solve this problem is required.

Accordingly, the present invention is to solve the above problems, an object of the present invention, to efficiently generate a high frequency AC power applied to the electrodeless fluorescent lamp to drive stably while increasing the light efficiency of the electrodeless fluorescent lamp To provide a high frequency generator.

The present invention also provides an electrodeless lamp with a unique design and long life, high efficiency, and high color rendering property.

In addition, it has a low calorific value not only reduces the cooling cost, but also to produce a natural color with high color rendering, to provide an electrodeless lamp that can meet the consumer's desire for well-being.

The electrodeless fluorescent lamp according to an aspect of the present invention for achieving the object of the present invention as described above is a bulb having a circular cross-section, a donut shape and filled with a gas filled therein, and a ferrite core, the bulb The high frequency includes a high frequency generator coupled to the to generate a high frequency, characterized in that to induce ultraviolet light by reacting with the encapsulation gas.

The high frequency generator comprises: an EMI filter for filtering electromagnetic waves of the incoming AC signal; And a rectifier for generating the DC signal from the signal from which the electromagnetic wave is filtered, and when generating the DC signal from the signal from which the electromagnetic wave is filtered, filtering the electromagnetic wave to correct a power factor of the incoming AC signal. It may further include a PFC circuit for controlling the phase of the signal.

The oscillation control circuit includes: a first capacitor connected between a terminal of the output AC signal and a first node; A second capacitor connected between the first node and a second node; A first inductor coupled between the second node and a terminal of the first ramp signal; A third capacitor connected between the terminal of the first ramp signal and a third node; A second inductor connected between the third node and a terminal of the second lamp signal; And a first resistor coupled between the third node and ground.

The second inductor is a first coil of a transformer, and the oscillation control circuit uses the first ramp signal and the second coil of the transformer according to a dimmer control signal by using a signal received from the second coil of the transformer. A determination circuit for generating a first dimmer signal and a second dimmer signal for determining the oscillation of the ramp signal; A first MOSFET of the N channel whose drain is connected to a predetermined power supply; A second MOSFET of N channel having a source connected to ground; A first auxiliary circuit adjusting a voltage of the first dimmer signal between a gate and a source of the first MOSFET, and supplying the adjusted first dimmer signal to the gate of the first MOSFET; And a second auxiliary circuit configured to adjust the voltage of the second dimmer signal between the gate and the source of the second MOSFET, and supply the adjusted second dimmer signal to the gate of the second MOSFET.

The oscillation control circuit may further include a variable resistor for generating the dimmer control signal.

The determination circuit generates a protection signal informing of a short circuit or opening of the first ramp signal or the second ramp signal, and the oscillation control circuit selectively converts the output AC signal to the first capacitor in accordance with the protection signal. It may further include a protection circuit for outputting.

The determination circuit may include a protection signal generation unit configured to generate the protection signal from the signal received from the first ramp signal and the second coil of the transformer; A comparison unit comparing a first voltage corresponding to a signal received from the first lamp signal and a second coil of the transformer with a second voltage corresponding to the dimmer control signal; And a frequency determiner configured to increase or decrease the frequencies of the first dimmer signal and the second dimmer signal by a predetermined magnitude to fix the frequencies of the first ramp signal and the second ramp signal according to the comparison result. .

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings and the contents described in the accompanying drawings, but the present invention is not limited or limited to the embodiments. Like reference numerals in the drawings denote like elements.

1 is a perspective view illustrating an electrodeless lamp. As shown therein, the electrodeless lamp 120 includes a bulb 121 and a ferrite core 126.

The bulb 121 seals the encapsulation gas therein, and has a circular cross section and is curved in a donut shape as a whole. The bulb 121 is bent in a rectangular shape having two long sides 122 and two short sides 123, respectively, and the curved interior is empty like a donut.

The bulb 121 has no electrodes (filaments, light emitting tubes) like ordinary fluorescent lamps, and contains various mixed gases.

The ferrite core 126 is mounted to the bulb 121, and the two ferrite cores 126 are disposed to face each other. It is apparent that the number and mounting positions of the ferrite cores 126 may vary.

2 is a block diagram of a lighting system according to the present invention, Figure 3 is a block diagram of a lighting system showing a high frequency generator in more detail according to an embodiment of the present invention.

Referring to this, referring to this, the ferrite core 126 is part of the high frequency generator 124 and is connected to the circuit unit of the high frequency generator 124. The high frequency generator 124 is connected to an external power source 125 to receive power.

The high frequency generator 124 of the lighting system may include an electromagnetic interference (EMI) filter 111, a rectifier 112, a power factor correlation circuit 113, a DC-AC inverter 114. ), And an oscillation control circuit 115.

The electrodeless lamp 120 is a light source capable of emitting light to the electrodeless without a filament (light filament) or a light emitting plate having a common fluorescent lamp inside the discharge tube. As shown in FIG. 2, the electrodeless lamp 120 may be made in an annular shape. However, the present invention is not limited thereto, and the electrodeless lamp 120 may be manufactured in other shapes such as a quadrangle, a coil type, a parallelogram, and the like according to a user's request.

The electrodeless lamp 120 receives high frequency AC power from the high frequency generator 124 through a coil wound around a ferrite core. As shown in FIG. 1 or FIG. 2, the ferrite cores mounted on the electrodeless lamp 120 may be installed at each side of the discharge tube. At this time, one terminal of the coils wound on the two ferrite cores are connected to each other, and one terminal of each coil receives high frequency AC power from the high frequency generator 124.

When a high frequency AC power is applied from the high frequency generator 124, an induction electric field is generated inside the discharge tube according to the operation of the coils wound around the two ferrite cores of the electrodeless lamp 120. The induction electric field thus generated excites the encapsulating gas inside the discharge tube, for example, an inert gas such as mercury, and the generated electrons excite other particles again, creating ultraviolet rays by the high energy gas particles. . At this time, the visible light is finally emitted by the reaction of the three-wavelength fluorescent material applied to the inside of the discharge tube with ultraviolet rays. Since the electrodeless lamp 120 has a long lifespan unlike a general electrode lamp such as a metal lamp or a sodium lamp, the electrodeless lamp 120 reduces pollution of heavy metal gas and provides an environmentally friendly light source.

Hereinafter, the high frequency generator 124 for generating the high frequency AC power to drive the electrodeless lamp 120 will be described in detail. In particular, the high frequency generator 124 is designed to stably drive the electrodeless lamp 120 manufactured at low cost and long in life with high light efficiency, for example, 80lm / W or more. The high frequency AC power generated by the high frequency generator 124 has a lower operating frequency than that of the prior art, for example, 0.1 to 0.4 MHz, thereby reducing electromagnetic interference.

In FIG. 3, the EMI filter 111 included in the high frequency generator 124 filters an incoming alternating current (AC) signal, for example, an electromagnetic wave of a 220 volt AC power signal in a home. The voltage level of the power supply to the home may not be ideally supplied due to instability of the supplier's equipment or the external environment, eg thunder, lightning or other factors, to minimize the effects of electromagnetic interference that may occur. In order to achieve the EMI filter 111. The EMI filter 111 limits the incoming AC signal not to become larger or smaller than a predetermined size.

The rectifier 112 generates a direct current (DC) signal from the signal from which the electromagnetic wave is filtered. A bridge type diode circuit may be used as the rectifier 112.

In addition, when the rectifier 112 generates the DC signal from the signal from which the electromagnetic wave is filtered, the PFC circuit 113 may be used to correct a power factor of the incoming AC signal. The PFC circuit 113 reduces reactive power by controlling a phase of the signal filtered by the electromagnetic wave using a power capacitor. The PFC circuit 113 may supply stable current to subsequent circuits, minimize power loss, and reduce interference of electromagnetic waves.

As described above, the DC signal stably generated according to the operation of the rectifier 112 and the PFC circuit 113 is converted into an AC signal by the DC / AC inverter 114 and the DC / AC inverter 114. Generates an output AC signal oscillating at a frequency higher than the frequency of the AC signal drawn into the EMI filter 111. For example, the frequency of the AC signal introduced into the EMI filter 111 is typically about 60 Hz, and the frequency of the output AC signal from the DC / AC inverter 114 may be 0.25 MHz.

The output AC signal generated from the DC / AC inverter 114 is controlled by the oscillation control circuit 115 and then supplied to two terminals A1 and A2 of the coil of the electrodeless lamp 120. That is, the oscillation control circuit 115 generates a first ramp signal through at least one capacitor and at least one inductor connected in series with the terminal of the output AC signal, and generates a passive device. ) Generates a second ramp signal from the first ramp signal. The oscillation control circuit 115 supplies the first lamp signal and the second lamp signal to two terminals A1 and A2 of the coil of the electrodeless lamp 120.

FIG. 5 is a diagram for explaining the oscillation control circuit 115 of FIG. 3. Referring to FIG. 5, the oscillation control circuit 115 may include a first capacitor C1, a second capacitor C2, a first inductor L1, a third capacitor C3, a transformer L2, The first resistor R1 and the second resistor R2 are included. In addition, the oscillation control circuit 115 may include a protection circuit 310, a determination circuit 320, a first MOSFET Q1, a second MOSFET Q2, a first auxiliary circuit 330, and a second auxiliary circuit ( 340).

The first capacitor C1 is connected between the terminal of the output AC signal generated by the DC / AC inverter 114 and the first node ND1. The second capacitor C2 is connected between the first node ND1 and the second node ND2. The first inductor L1 is connected between the second node ND2 and one terminal A1 of the coil of the electrodeless lamp 120. That is, the output AC signal is a first lamp signal through the first capacitor C1, the second capacitor C2, and the first inductor L1, and the first lamp signal is the electrodeless lamp ( It is supplied to one terminal A1 of the coil of 120.

The third capacitor C3 is connected between the terminal A1 of the first ramp signal and the third node ND3. The first resistor R1 is connected between the third node ND3 and the ground GND. The first coil of the transformer L2 is connected between the third node ND3 and the other terminal A2 of the coil of the electrodeless lamp 120. That is, the first ramp signal is a second ramp signal by the first coil of the third capacitor C3, the first resistor R1, and the transformer L2, and the second ramp signal is the second ramp signal. It is supplied to the other terminal A2 of the coil of the electrodeless lamp 120. The first coil of the transformer L2 connected between the third node ND3 and the terminal A2 of the second ramp signal acts as an inductor.

The decision circuit 320 uses the first ramp signal at A1 and a signal received from the second coil of the transformer L2 interacting with the first coil of the transformer L2 between A2 and ND3. According to the dimmer control signal DIM, a first dimmer signal DMO1 and a second dimmer signal DMO2 for determining oscillation frequencies of the first ramp signal and the second ramp signal are generated.

The dimmer control signal DIM is generated by the second resistor R2 connected between the predetermined element in the determination circuit 320 and the ground GND. The second resistor R2 may be a variable resistor, and the brightness of the electrodeless lamp 120 may be adjusted by changing the value of the second resistor R2. That is, the brightness can be adjusted by dividing the road or the room by varying the second resistor R2, thereby contributing to the reduction of power consumption.

For this dimmer operation, the drain of the first MOSFET Q1 is connected to the power supply VCC, and the source of the second MOSFET Q2 is connected to the ground GND. The first MOSFET Q1 and the second MOSFET Q2 are preferably N-channel MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors).

The first auxiliary circuit 330 adjusts the voltage of the first dimmer signal DMO1 between the gate and the source of the first MOSFET Q1, and adjusts the voltage of the first dimmer signal DMO1. Supply to the gate of the first MOSFET (Q1). The first auxiliary circuit 330 may include a transformer, a resistor, a diode, etc. to adjust the voltage of the first dimmer signal DMO1.

The second auxiliary circuit 340 adjusts the voltage of the second dimmer signal DMO2 between the gate and the source of the second MOSFET Q2, and adjusts the voltage of the second dimmer signal DMO2. Supply to the gate of the second MOSFET (Q2). The second auxiliary circuit 340 may include a resistor, a diode, etc. to adjust the voltage of the second dimmer signal DMO2.

As described above, when the first dimmer signal DMO1 and the second dimmer signal DMO2 are adjusted to drive the first MOSFET Q1 and the second MOSFET Q2, The voltage or frequency is changed, and thus, the frequencies of the first lamp signal and the second lamp signal supplied to the two terminals A1 and A2 of the coil of the electrodeless lamp 120 may vary. To this end, the first dimmer signal DMO1 and the second dimmer signal DMO2 may have an AC shape having a predetermined frequency.

For example, when the frequency of the signal supplied to the electrodeless lamp 120 is increased by the first dimmer signal DMO1 and the second dimmer signal DMO2, the ferrite core of the electrodeless lamp 120 is increased. As the value of the inductance component of the wound coil is increased, the brightness of the electrodeless lamp 120 is reduced and power consumption is also reduced. On the contrary, when the frequency of the signal supplied to the electrodeless lamp 120 decreases due to the first dimmer signal DMO1 and the second dimmer signal DMO2, it is wound around the ferrite core of the electrodeless lamp 120. By reducing the value of the inductance component of the coil, the brightness of the electrodeless lamp 120 is increased and power consumption is also increased.

 In addition, the determination circuit 320 may generate a protection signal PROT indicating a short circuit or an opening of the first ramp signal or the second ramp signal. Accordingly, the protection circuit 310 selectively outputs the high frequency output AC signal generated by the DC / AC inverter 114 to the first capacitor C1 according to the protection signal PROT. The first lamp signal or the second lamp signal may be opened or shorted by any cause at the electrodeless lamp 120. When the first lamp signal or the second lamp signal is open, since the electrodeless lamp 120 does not operate normally, the first capacitor outputs the high frequency output AC signal generated by the DC / AC inverter 114 to the first capacitor. There is no need to output to (C1). In addition, when the first lamp signal or the second lamp signal is short-circuited, the coil of the electrodeless lamp 120 or the circuit of each part of the oscillation control circuit 115 may be damaged due to overcurrent. It is not necessary to output the high frequency output AC signal generated by the DC / AC inverter 114 to the first capacitor C1.

FIG. 6 is a diagram for describing the decision circuit 320 of FIG. 5. Referring to FIG. 6, the decision circuit 320 includes a comparator 410, a frequency determiner 420, and a protection signal generator 430.

The comparator 410 is a signal flowing into the electrodeless lamp 120, that is, the first lamp signal at A1 and the transformer interacts with the first coil of the transformer L2 between A2 and ND3. A signal received from the second coil of L2 is collected, and a corresponding DC voltage is detected. Accordingly, the comparison unit 410 compares the detected predetermined DC voltage with the DC voltage corresponding to the dimmer control signal DIM generated through the second resistor R2 in FIG. 3.

According to a comparison result of the comparison unit 410, the frequency determiner 420, the first dimmer signal (DMO1) and the second dimmer to fix the frequency of the first ramp signal and the second ramp signal The frequency of the signal DMO2 is increased or decreased by a predetermined amount. For example, in order to fix the frequencies of the first ramp signal and the second ramp signal at a frequency higher (or lower) than the current frequency, the first dimmer signal DMO1 and the second dimmer signal DMO2. Do not raise (or lower) the frequency of at once. When the frequencies of the first dimmer signal DMO1 and the second dimmer signal DMO2 are increased (or decreased) by a predetermined magnitude, the comparison unit 410 according to the feedback of the first ramp signal and the second ramp signal. And the comparison result is different. Accordingly, the frequency determiner 420 determines whether to further increase (or decrease) the frequencies of the first dimmer signal DMO1 and the second dimmer signal DMO2. Generates corresponding dimmer signals.

In addition, the protection signal generator 430 may generate a protection signal PROT indicating a short circuit or an opening of the first lamp signal or the second lamp signal. The protection signal generator 430 interacts with a signal introduced into the electrodeless lamp 120, that is, the first lamp signal at A1 and the first coil of the transformer L2 between A2 and ND3. The protection signal PROT is generated from a signal received from the second coil of the transformer L2. Accordingly, the protection circuit 310 selectively outputs the high frequency output AC signal generated by the DC / AC inverter 114 to the first capacitor C1 of FIG. 3 according to the protection signal PROT. .

Table 1 is presented to show the effect of the electrodeless fluorescent lamp as described above. Table 1 shows the experimental data showing the color rendering, luminous flux and power factor according to the lamp rating.

As shown in Table 1, the conventional discharge lamp emits a high amount of heat generated to reach a high temperature of 300 ~ 400 ° C, such as energy waste and room temperature rise, while the electrodeless fluorescent lamp is approximately 80 ~ 90 It has a low calorific value of ° C has the effect of reducing the cooling cost. In addition, since the high color rendering to produce a natural color, there is an effect that can meet the needs of consumers who want well-being.

In addition, it has a 35% energy saving effect compared to existing discharge lamps. The average life span measured up to 60% of the initial luminous flux is about 100,000 hours, and the effective surface area measured up to 70% of the initial luminous flux is 60,000 hours. It has a long life, such as to reduce the maintenance cost.

Apparatus and method according to the present invention can be implemented in the form of program instructions that can be executed by various computer means may be recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention, or may be known and available to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks, such as floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. The medium may be a transmission medium such as an optical or metal wire, a waveguide, or the like including a carrier wave for transmitting a signal specifying a program command, a data structure, or the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

Although the present invention has been described with reference to the limited embodiments and drawings, the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the utility model registration claims as described below and equivalents to the utility model registration claims.

As described above, in the high frequency generator according to the present invention, the electrodeless lamp manufactured at low cost and long in life can be stably driven with high efficiency. In addition, since the electrodeless lamp can be driven at a relatively low operating frequency, electromagnetic interference is reduced, and brightness can be adjusted by dividing the road or the room, thereby contributing to the reduction of power consumption. In addition, since it operates to ensure a long life of the electrodeless lamp, it can contribute to reducing pollution of heavy metal gas and providing an environment-friendly light source.

In addition, it has a 35% energy saving effect compared to existing discharge lamps. The average life span measured up to 60% of the initial luminous flux is about 100,000 hours, and the effective surface area measured up to 70% of the initial luminous flux is 60,000 hours. It has a long lifespan, such as to reduce the maintenance cost.

Claims (9)

A bulb having a circular cross section, curved in a donut shape, and filled with a gas filled therein; And A high frequency generator having a ferrite core and coupled to the bulb to generate a high frequency; Including; The high frequency generator A DC / AC inverter for generating an output AC signal that oscillates a DC signal generated from an incoming AC signal at a frequency higher than a frequency of the incoming AC signal; Generating a first ramp signal through at least one capacitor and at least one inductor serially connected to a terminal of the output AC signal, and generating a second ramp signal from the first ramp signal using a passive element; And an oscillation control circuit for supplying a lamp signal and the second lamp signal to two terminals of the coil of the electrodeless lamp, wherein the high frequency wave reacts with the encapsulating gas to induce ultraviolet light. The method of claim 1, The oscillation control circuit A first capacitor coupled between the terminal of the output AC signal and a first node; A second capacitor connected between the first node and a second node; A first inductor coupled between the second node and a terminal of the first ramp signal; A third capacitor connected between the terminal of the first ramp signal and a third node; A second inductor coupled between the third node and a terminal of the second ramp signal; And A first resistor coupled between the third node and ground; Three-wavelength electrodeless fluorescent lamp comprising a. The method of claim 2, The second inductor is a three-wavelength electrodeless fluorescent lamp, characterized in that the first coil of the transformer. The method of claim 3, The oscillation control circuit A first dimmer signal and a second dimmer signal for determining oscillation of the first ramp signal and the second ramp signal according to a dimmer control signal by using the signal received from the first ramp signal and the second coil of the transformer; A decision circuit to generate; A first MOSFET of the N channel whose drain is connected to a predetermined power supply; A second MOSFET of N channel having a source connected to ground; A first auxiliary circuit adjusting a voltage of the first dimmer signal between a gate and a source of the first MOSFET, and supplying the adjusted first dimmer signal to the gate of the first MOSFET; And A second auxiliary circuit configured to adjust a voltage of the second dimmer signal between a gate and a source of the second MOSFET, and supply the adjusted second dimmer signal to the gate of the second MOSFET; Three-wavelength electrodeless fluorescent lamp further comprising a. The method of claim 4, wherein The oscillation control circuit And a variable resistor for generating the dimmer control signal. The method of claim 4, wherein The determining circuit generates a protection signal informing of a short or an opening of the first ramp signal or the second ramp signal, The oscillation control circuit, And a protection circuit for selectively outputting the output AC signal to the first capacitor in accordance with the protection signal. The method of claim 6, The decision circuit is A protection signal generator configured to generate the protection signal from the signal received from the first ramp signal and the second coil of the transformer; A comparison unit comparing a first voltage corresponding to the first ramp signal with a signal received from the second coil of the transformer and a second voltage corresponding to the dimmer control signal; And And a frequency determination unit configured to increase or decrease the frequencies of the first dimmer signal and the second dimmer signal by a predetermined magnitude to fix the frequencies of the first ramp signal and the second ramp signal according to the comparison result. A three-wave long electrodeless fluorescent lamp characterized by. delete delete

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