KR20130026634A - Led fluorescent lamp - Google Patents

Abstract

PURPOSE: An LED fluorescent lamp is provided to increase lifetime of an LED fluorescent lamp by preventing high-frequency on-off switching of an LED, and to increase luminance efficiency and to be usable with a regulator for an existing fluorescent lamp without changing a separate designated regulator or a line and by minimizing a crest factor of LED operating current. CONSTITUTION: An LED fluorescent lamp including a capacitive device unit changing impedance of a fluorescent lamp regulator connected through an external connection pin while being connected between an LED array and an external connection pin includes an external connection pin including a first connection pin and a second connection pin, an LED array(310) including a plurality of serially connected LEDs and a capacitor(320) for current regulation while being connected in parallel with the LED array. [Reference numerals] (310) LED array

Description

LED Fluorescent Lamp {LED FLUORESCENT LAMP}

The present invention relates to an LED fluorescent lamp, and more particularly to a long-life, high-efficiency LED fluorescent lamp having an internal structure that can use the ballast of the existing fluorescent lamp as it is.

With the development of technology, the light efficiency of LEDs (Light Emitting Diodes), which have been used only for small power indicators such as indicators in the past, is being improved enough to be used in real life. In addition, unlike other light sources, LED is an environmentally friendly light source that does not contain mercury, and is widely used as a next-generation light source used for a backlight for a mobile phone, a backlight for an LCD TV, a vehicle lamp, and general lighting. In the 2000s, the cost of power generation increased rapidly due to the rise in oil prices.In response to the rise of environmental problems, incandescent and fluorescent lamps, which have been used as the main light source for lighting for the last 100 years, are being replaced by LED lamps. .

However, in the case of LED lamps, incandescent lamps can be replaced in the case of E26 base compatible lamps, but when replacing fluorescent lamps that are the mainstream of general lighting, lighting fixtures or dedicated ballasts must be installed separately. . Therefore, there is a difficulty in changing the wiring inside the luminaire, so that the fluorescent LED lamp is not widely used.

An object of the present invention is to increase the light efficiency of the LED fluorescent lamp by increasing the lifetime of the LED fluorescent lamp as much as possible by preventing the LED from switching on / off switching at high frequency and to minimize the crest factor of the LED operating current It is to provide LED fluorescent lamp that can be used in existing fluorescent ballast without changing dedicated ballast or wiring.

An embodiment of the present invention, an external connection pin including a first connection pin and a second connection pin, an LED array including a plurality of LEDs connected in series, a current stabilizing capacitor connected in parallel with the LED array and the The LED fluorescent lamp may include a capacitive element connected between an LED array and the external connection pin to change an impedance of a fluorescent ballast connected through the external connection pin.

According to another aspect of the present invention, the external connection pin may further include a third connection pin and a fourth connection pin, wherein the capacitive element part is connected to the first connection pin at one end and the other end of the LED array. A first capacitor connected to an anode side terminal of the first terminal, one end of which is connected to the second connection pin, the other end of which is connected to a cathode side terminal of the LED array, and one end of the third connection pin The other end may include at least one of a third capacitor connected to an anode side terminal of the LED array, and one end of which is connected to the fourth connection pin, and the other end of which is connected to a cathode side terminal of the LED array. Can be.

Yet another aspect of the present invention may further include a diode unit connected to both ends of the LED array to form a one-way current path in the LED array.

According to the present invention, it is possible to use an existing ballast for fluorescent lamps without installing a separate dedicated ballast or changing wiring inside the luminaire, there is no flicker phenomenon, and a long-life, high-efficiency LED fluorescent lamp is provided. Therefore, it is possible to simply replace the existing fluorescent lamp without incurring a special cost, making it easier to use the environment-friendly, high efficiency lighting.

1 is a basic configuration diagram of an LED fluorescent lamp.
2 is a graph showing the voltage applied to the LED fluorescent lamp and the current waveform flowing through the LED array.
3 is a circuit diagram of an LED fluorescent lamp according to one embodiment of the present invention.
4 is a circuit diagram of an LED fluorescent lamp according to another embodiment of the present invention.
5 is a circuit diagram of an LED fluorescent lamp according to still another embodiment of the present invention.
6 is a circuit diagram of an LED fluorescent lamp according to still another embodiment of the present invention.
7 is a circuit diagram of an LED fluorescent lamp according to still another embodiment of the present invention.
8 is a circuit diagram of an LED fluorescent lamp according to still another embodiment of the present invention.
9 is a circuit diagram of an LED fluorescent lamp according to still another embodiment of the present invention.
10A to 10D are graphs for explaining the operation of the LED fluorescent lamp according to the embodiment of the present invention.

Hereinafter, with reference to the drawings will be described the present invention in more detail.

1 is a configuration diagram of an LED fluorescent lamp. The LED fluorescent lamp 100 is a LED array 110, a plurality of capacitors (131, 132, 133, 134) and a plurality of diodes (141, 142, 143, 144, 145, 146, 147, 148, 149, 150 ) May be included. The LED fluorescent lamp can be operated even if the LED fluorescent lamp is directly connected to the conventional fluorescent lamp ballast by the plurality of capacitors and diodes. The operation and characteristics of such LED fluorescent lamps are described in detail in Korean Patent No. 0981854. In the present specification, 'LED fluorescent lamp' refers to a fluorescent lamp type lamp using the LED as a light source, the external shape includes a variety of forms, such as straight, curved.

2 is a graph illustrating a voltage waveform (1) applied to the LED array and a current waveform (2) flowing through the LED array when the LED fluorescent lamp of FIG. 1 is driven by an electronic ballast having high frequency operation.

Referring to FIG. 2, the voltage waveform (①) applied to the LED array forms a sine wave shape, and the current (②) flows in the LED array only in a section in which the applied voltage is greater than or equal to the threshold value V _{TH of} the LED array. do. Therefore, in the section tb-tc in which the lamp voltage is less than or equal to the threshold of the LED array, a dark angle in which no current flows in the LED array occurs, resulting in a decrease in light efficiency of the entire LED array and on / off every cycle. The in-rush current flows by the operation, which shortens the life of the LED fluorescent lamp.

3 is a circuit diagram of an LED fluorescent lamp 300 according to one embodiment of the present invention.

The LED fluorescent lamp 300 according to the present embodiment includes first to fourth external connection pins 1, 2, 3, and 4, an LED array 310, a current stabilizing capacitor 320, and a capacitive element unit 331. , 332, 333, 334.

The LED array 310 may include a plurality of LEDs connected in series, and a plurality of LEDs in series may be connected in parallel. The configuration of the LED array used in the present embodiment can be implemented in various ways, the LED may be an LED chip, may be a package or a chip on board (COB) package in which a plurality of LED chips are mounted.

The external connection pins 1, 2, 3, and 4 have a first external connection pin 1 and a third external connection pin 3 formed at one end of an anode side of the LED array 310, and a second external connection pin. The connection pin 2 and the fourth external connection pin 4 may be formed at the other end of the cathode side of the LED array 310. The first to fourth external connection pins can be used to mount the LED fluorescent lamp according to the present embodiment to a luminaire for a conventional fluorescent lamp. The four external connection pins may be connected to all four external connection pins to the ballast, depending on the shape of the ballast mounted in a conventional fluorescent lamp luminaire, one end and the other end of the external connection pins connected to one end of the LED array 310 Only the other of the external connection pins connected to the ballast may be connected to the ballast. In addition, by shorting the first external connection pin (1) and the third external connection pin (3) connected to one end of the LED array 310 to use as one external connection pin and the second external connection pin (2) connected to the other end It may also be possible to short the fourth external connection pin 4 to be used as another external connection pin.

The capacitive element units 331, 332, 333, and 334 may be connected to a circuit of an electronic fluorescent ballast connected through the external connection pin to change a resonant frequency of a series resonant circuit including an inductor and a capacitor, or an LED array. It may serve to control the current flowing in (310). In the present exemplary embodiment, the capacitive element unit may include a first capacitor 331 having one end connected to the first connection pin 1 and the other end connected to an anode side terminal of the LED array 310, and one end of the second capacitor 331. The second capacitor 332 is connected to the connecting pin (2) and the other end is connected to the cathode side terminal of the LED array 310, one end is connected to the third connection pin (3) and the other end is the LED array 310 A third capacitor 333 connected to an anode side terminal of the c) and one end connected to the fourth connection pin 4 and the other end of the fourth capacitor 334 connected to the cathode side terminal of the LED array 310. It may include.

In the figure, the first external connection pin and the third external connection pin, and the second external connection pin and the fourth external connection pin are shown in an open state (a), respectively, the LED fluorescent lamp of the present embodiment When connecting to an instant start ballast, the first external connection pin and the third external connection pin is shorted to obtain more stable and uniform optical characteristics (b), or the second external connection pin and the fourth external connection The connection pin may be formed by shorting (c) or shortening both the first external connection pin and the third external connection pin, and the second external connection pin and the fourth external connection pin (d).

라 놓고, 상기 전자안정기 내부의 커패시터가 상기 C1 보다 매우 크다고 하면, 이때의 LED 어레이(310)에 흐르는 전류는 When the LED fluorescent lamp is connected to the electronic ballast of the instant start method, the capacitance of the capacitors 331 to 334 connected to each external connection pin is referred to as C ₁ , and the angular velocity of the frequency of the voltage applied from the electronic ballast is determined.

If the capacitor inside the electronic ballast is much larger than the C1, the current flowing in the LED array 310 at this time is

In the case of (a) above

In the case of (b) and (c)

In the case of (d)

It is controlled by the composite impedance of.

The current stabilizing capacitor 320 may have one end connected to one end of the LED array 310 and the other end connected to the other end of the LED array 310 in parallel with the LED array.

Looking at the basic operation by the current stabilizing capacitor 320, the current flowing through the LED fluorescent lamp 300 by Kirchhoff's law can be expressed by the following equation.

은, 외부 안정기로부터 상기 외부 연결핀을 통해 LED 형광램프로 흐르는 전류,

는 LED 어레이(310)에 흐르는 전류,

는 전류안정용 캐패시터(320)를 흐르는 전류를 나타낸다. here,

Silver, the current flowing from the external ballast to the LED fluorescent lamp through the external connection pin,

Is a current flowing in the LED array 310,

Denotes a current flowing through the current stabilizing capacitor 320.

Here, when the capacitance value of the current stabilizing capacitor 320 connected in parallel across the LED array 310 is more than a few tens of microfarads (uF) capable of supplying a sufficient current to the LED array, the LED by the current stabilizing capacitor 320 In the array 310, a smooth DC current always flows.

By the above equation 1,

는 안정기로부터의 전류 값

에서 전류안정용 캐패시터(320)를 통해 흐르는 전류값인

를 뺀 값 즉

만큼 역 바이어스가 걸린 값으로 나타낼 수 있다.It can be obtained, the current flowing through the LED array 310

Is the current value from the ballast

Is a current value flowing through the current stabilizing capacitor 320 at

Minus

Can be expressed as a reverse biased value.

Therefore, assuming that the value of the current stabilizing capacitor 320 is sufficiently large, the smoothing DC current flows through the LED array load by the role of the capacitor 320, and thus the pulse voltage component from the ballast as shown in FIG. It is possible to prevent the dark section of the operating current caused by the LED, and the LED fluorescent lamp luminous flux efficiency is improved by decreasing the crest factor of the current by the direct current flowing through the LED array, and the LED array is turned on / off during every operating cycle. By preventing the in-rush current by the long life of the LED fluorescent lamp is possible.

In the LED fluorescent lamp described in the following embodiments, the LED array and the current stabilizing capacitor connected in parallel with the LED array are both included as common components. Therefore, in the following description, redundant description of the LED array and the current stabilizing capacitor will be omitted, and the description will be mainly focused on the characteristic configuration and operation in each embodiment.

4 is a circuit diagram of an LED fluorescent lamp 400 according to another embodiment of the present invention.

In the embodiment of FIG. 4, a first diode 441 and a second diode 442 connected in series with both ends of the LED array 410 are added as compared to the LED fluorescent lamp according to the embodiment of FIG. 3. The first diode 441 and the second diode 442 may allow current to flow in the LED array 410 only in the forward direction. Therefore, when the zener diodes are connected in parallel to the LEDs in the LED array 410 in the reverse direction, current may flow through the zener diodes in a negative period to prevent power loss from occurring. In the present embodiment, two diodes 441 and 442 are included, but only one diode of the two diodes may be connected according to the use environment.

5 is a circuit diagram of an LED fluorescent lamp 500 according to another embodiment of the present invention.

The LED fluorescent lamp 500 according to the embodiment of FIG. 5 may further include third to tenth diodes 543 to 550 as compared to the LED fluorescent lamp according to the embodiment of FIG. 4. In this embodiment, the third, fourth, fifth, and sixth diodes 543, 544, 545, 546 are respectively opposite both ends of the first to fourth capacitors 531, 532, 533, 534. It is connected to the first to the fourth capacitor may be connected in parallel. The third to sixth diodes 543, 544, 545, and 546 may appear to be short or open according to the phase of the voltage applied from the electronic ballast, and thus, the first to fourth connected in parallel. Capacitors 531, 532, 533, and 534 and the series resonant capacitor C inside the electronic ballast may be combined to change a complex impedance for controlling current.

When the LED fluorescent lamp according to the present embodiment is connected to a half bridge fluorescent lamp ballast having a series resonance circuit, the third and fourth external connection pins 3 and 4 are respectively switched outputs of the ballast internal inverter. The first and second external connection pins 1 and 2 may be connected to the capacitor C for series resonance inside the ballast. At this time, when the potential of the third external connection pin 3 is higher than the potential of the fourth connection pin 4, the third external connection pin 3-the fifth diode 545-the first capacitor 531. ), The external resonant capacitor C-the second capacitor 532-the current flows in the path of the sixth diode 546, the potential of the third external connection pin (3) is the potential of the fourth external connection pin (4) If lower, the fourth external connection pin 4-the fourth capacitor 534-the fourth diode 544-the external resonant capacitor C-the third diode 543-the third capacitor 533-the third Current flows through the path of the external connection pin 3 and changes the capacitances of the four capacitors 531-534 so that at least some of the four capacitors 531-534 and the composite impedance of the external resonant capacitor C in series configuration It is possible to control the current flowing in the LED array 500 by changing the.

The seventh to tenth diodes 547, 548, 549, and 550 serve to operate a LED fluorescent lamp by allowing a forward current to flow in the LED array regardless of a phase change of an AC voltage in various fluorescent ballasts. In charge.

In an improved form of the present embodiment, one end of the current stabilizing capacitor 520 may be connected to the anode of the first diode 541 and the other end may be connected to the cathode of the second diode 542. .

6 is a circuit diagram of an LED fluorescent lamp 600 according to still another embodiment of the present invention.

In the LED fluorescent lamp 600 according to the present embodiment, the third to sixth diodes 643, 644, 645, and 646 are respectively compared to the LED fluorescent lamp according to the embodiment of FIG. 5. It is connected in series. The third to sixth diodes 643, 644, 645, and 646 and the seventh to tenth diodes 647, 648, 649, and 650 are forward currents to the LED array regardless of the phase of the AC voltage in various ballasts. Can be made to operate the LED fluorescent lamp according to the present embodiment.

When the LED fluorescent lamp 600 according to the present embodiment is connected to the electronic fluorescent lamp ballast of the instant start method, the first external connection pin 1 and the second external connection pin 2 are connected to the output line of the ballast. The third external connection pin 3 and the fourth external connection pin 4 may be open or shorted. An internal capacitor connected in series to the first external connection pin 1 of the LED fluorescent lamp may be disposed in the ballast.

When the output from the electronic ballast is applied to the first external connection pin 1 and the second external connection pin 2, the voltage of the first external connection pin 1 is reduced to that of the second external connection pin 2. If the voltage is higher than the current, the current is controlled by the current control capacitor inside the ballast-the first external connection pin 1-the first capacitor 631-the third diode 643-the first diode 641-the LED array 610 and It may flow through the current stabilizing capacitor 620, the second diode 642, the fourth diode 644, the second capacitor 632, and the second external connection pin 2. On the contrary, when the voltage of the first external connection pin 1 is lower than the voltage of the second external connection pin 2, the current is changed from the second external connection pin 2 to the second capacitor 632 to the eighth diode 648. )-First diode 641-LED array 610 and current stabilizing capacitor 620-second diode 642-seventh diode 647-first capacitor 631-first external connection pin 1 )-Can flow through the current control capacitor inside the ballast. That is, the current value flowing through the LED array and the current stabilizing capacitor 620 is controlled by the series complex impedance of the capacitor inside the ballast and the first capacitor 631 and the second capacitor 632 in the electronic ballast. When the capacitance of the ballast internal capacitor is C and the capacitances of the first to fourth capacitors 631-634 are each C ₁ , a complex impedance for controlling the current flowing through the LED array 610 and the current stabilizing capacitor 620. Is

As shown in Fig.

In addition, the third external connection pin 3 and the fourth external connection pin 4 is connected to the output line of the ballast of the instant start method, the first external connection pin 1 and the second external connection pin ( 2) may be in the open form, the direction of the current is controlled by the fifth, sixth, ninth, and tenth diodes (645, 646, 649, 650), the current can flow in the LED array, Even in this case, the current value flowing through the LED array is a series complex impedance value of the capacitor-third capacitor 633 and the fourth capacitor 634 in the ballast as described above.

To be controlled.

The first external connection pin 1 and the third external connection pin 3 and / or the second external connection pin 2 and the fourth external connection pin 4 according to the form of the instant start ballast. In this case, the current control complex impedance value is

이 된다.

.

In an improved form of the present embodiment, one end of the current stabilizing capacitor 620 may be connected to the anode of the first diode 641 and the other end may be changed to the cathode of the second diode 642. .

7 is a circuit diagram of an LED fluorescent lamp 700 according to still another embodiment of the present invention.

The LED fluorescent lamp 700 according to the embodiment of FIG. 7 includes an LED array 710, a current stabilizing capacitor 720 connected in parallel with the LED array, and first to fourth connecting pins 1, 2, 3, and 4. And first to fourth capacitors 731, 732, 733, and 734 having one end connected to the first to fourth external connection pins 1, 2, 3, and 4, respectively, wherein a forward current is applied to the LED array. It may include a diode portion disposed to flow.

The diode unit may include a first diode 741 having an anode connected to the other end of the first capacitor 731 and a cathode connected to one end of the LED array 710, and an anode connected to the other end of the LED array 710. A cathode connected to the other end of the second capacitor 732, a cathode connected to the other end of the second capacitor 732, and a cathode connected to one end of the LED array 710. The diode 743 and the anode may include a fourth diode 744 connected to the other end of the LED array 710 and the cathode connected to the other end of the third capacitor 733.

The first diode 741 may allow a current flowing through the first external connection pin 1 or the third external connection pin 3 to flow into the LED array, and the second diode 742 may be connected to the LED array. It is possible to prevent the current flowing through the second external connection pin 2 and the fourth external connection pin 4 directly flowing in the reverse direction of the LED array 710. The third diode 743 may change the path of the current introduced through the second external connection pin 2 and the fourth external connection pin 4 so that the current flows in the forward direction to the LED array 710. In addition, the fourth diode 744 has a current flowing through the second external connection pin 2 and the fourth external connection pin 4 through the LED array 710 to allow the first external connection pin ( 1) or to the third external connection pin (3). That is, the third diode 743 and the fourth diode 744 are the present embodiment irrespective of the phase change of the voltage applied to the first to fourth connection pins 1, 2, 3, and 4 in various fluorescent ballasts. LED fluorescent lamp according to the operation can be made.

In the figure, the first external connection pin and the third external connection pin, and the second external connection pin and the fourth external connection pin are shown in the open state, respectively, the instantaneous start of the LED fluorescent lamp of the present embodiment When the ballast is connected to the ballast, the first external connection pin and the third external connection pin is shorted, or the second external connection pin and the fourth external connection pin are shorted to obtain more stable and uniform optical characteristics. In addition, the first external connection pin and the third external connection pin, and the second external connection pin and the fourth external connection pin may be formed by shorting.

8 is a circuit diagram of an LED fluorescent lamp 800 according to still another embodiment of the present invention.

The LED fluorescent lamp 800 according to the present embodiment includes an LED array 810, a current stabilizing capacitor 820 connected in parallel with the LED array, first to fourth connecting pins 1, 2, 3, and 4, and First to fourth capacitors 831, 832, 833, and 834 having one end connected to the first to fourth external connection pins 1, 2, 3, and 4, respectively, so that forward current flows through the LED array. It may include a diode unit disposed.

The LED fluorescent lamp 800 according to the embodiment of FIG. 8 has only the directions of the fifth to eighth diodes 845, 846, 847, and 848 as compared to the LED fluorescent lamp 700 according to the embodiment of FIG. 7. Reversed. As such, even if the polarities are reversely connected, only the path through which the current flows is different, and the basic operation may be the same as described above with reference to FIG. 7.

9 is a circuit diagram of an LED fluorescent lamp 900 according to still another embodiment of the present invention.

The LED fluorescent lamp 900 according to the present embodiment includes an LED array 910, a current stabilizing capacitor 920 connected in parallel with the LED array, first to fourth connecting pins 1, 2, 3, and 4, and First to fourth capacitors 931, 932, 933, and 934 having one end connected to each of the first to fourth external connection pins 1, 2, 3, and 4 so that a forward current flows through the LED array. It may include a diode unit disposed.

The diode unit includes a first diode 941 having an anode connected to the other end of the first capacitor 931 and a cathode connected to one end of the LED array 910, and an anode connected to the other end of the LED array 910. And a second diode 942 having a cathode connected to the other end of the second capacitor 932, an anode connected to the other end of the LED array 910, and a cathode connected to the other end of the third capacitor 933. The third diode 943 and the anode may include a fourth diode 944 connected to the other end of the fourth capacitor 934 and a cathode connected to one end of the LED array 910.

In addition, the first to fourth capacitors 931, 932, 933, and 934 may include fifth to eighth diodes 945, 946, 947, and 948 connected in parallel.

In addition, a ninth diode 949 having an anode connected to the other end of the second capacitor 932 and a cathode connected to one end of the first capacitor 931, and an anode connected to one end of the second capacitor 932. And a tenth diode 950 having a cathode connected to the other end of the first capacitor 931, an anode connected to the other end of the third capacitor 933, and a cathode connected to one end of the fourth capacitor 934. The eleventh diode 951 and the anode may include a twelfth diode 952 connected to one end of the third capacitor 933 and a cathode connected to the other end of the fourth capacitor 934.

In the present embodiment, the first to fourth diodes 941, 942, 943, and 944 and the ninth to twelfth diodes 949, 950, 951, and 952 are used to connect the first to the fourth to various fluorescent ballasts. The LED fluorescent lamp according to the present embodiment can be stably operated regardless of the phase change of the AC voltage applied to the pins 1, 2, 3, and 4.

In an improved form of the present embodiment, one end of the current stabilizing capacitor 920 may be connected to the anode of the first diode 941, and the other end may be connected to the cathode of the second diode 942. In another modification, one end of the current stabilizing capacitor 920 may be connected to the third diode 943, and the other end may be connected to the anode of the fourth diode 944.

10A to 10D are graphs for explaining the operating characteristics of the LED fluorescent lamp according to the embodiment of the present invention.

(A) and (b) of FIG. 10 are measured by connecting an LED fluorescent lamp from which the current stabilizing capacitor 620 is removed from the LED fluorescent lamp 600 according to the embodiment of FIG. 6 to an instant start type electronic ballast. 10 (c) and 10 (d) are measured by connecting the LED fluorescent lamp 600 according to the embodiment of FIG. 6 to an instant start type electronic ballast.

In the graph of FIG. 10A, one of the first external connection pin 1 and the third external connection pin 3 and the second external connection pin 2, that is, the voltage applied across the LED fluorescent lamp 600, is illustrated. And the voltage v ₁ from the instant start type ballast applied to one of the fourth external connection pins 4 and the voltage v _d across the LED array after passing through the capacitors 631 to 634. It is shown that the phase of the voltage across the LED array is lag by t _d than the phase of the voltage across the LED fluorescent lamp by the role of the current control capacitors 631 to 634 connected across the LED array.

In the graph of Fig. 10 (b), it shows a current _(l i) flowing through the voltage (v _d) and LED arrays between the LED array. Since a plurality of diodes 647 to 650 disposed in the LED fluorescent lamp have currents flowing in the LED array in the forward direction even when the voltage across the LED fluorescent lamp is negative, the LED array 610 is connected. It can be seen that the frequency of the flowing current is twice the frequency of the voltage across the LED array. As such, when the current of the high frequency component flows through the LED array 610, the crest factor of the LED current is very high, and thus there is a disadvantage in that the high frequency flicker phenomenon and the luminous flux efficiency are deteriorated. Here, t _on represents a section in which current flows in the LED array, and t _off represents a section in which no current flows in the LED array.

The graph of Fig. 10 (c) shows the voltage v _{d at} both ends of the LED array when the current stabilizing capacitor 620 is connected to the LED array 610 in parallel, and the current flowing through the current stabilizing capacitor 620. (i _c ) A waveform is shown. Here, comparing the current waveform flowing through the LED array of FIG. 10 (b) with the current waveform flowing through the current stabilizing capacitor 620 of FIG. 10 (c) in comparison with FIG. 10 (b), the basic waveform is maintained as it is. It can be seen that the current flows by shifting the stabilized LED current value i _d in FIG. 10 (c).

Fig. 10 (d) shows the voltage v _d across the LED array and the current i _d flowing in the LED array 610 when the current stabilizing capacitor 620 is connected in parallel to the LED array 610. It is a graph.

Referring to (b), (c), and (d) of FIG. 10, when the current stabilizing capacitor 620 is connected in parallel with the LED array 610, high frequency components of current flowing through the entire LED fluorescent lamp are included. The current flows through the current stabilization capacitor, and the constant current from which the high frequency component is removed flows through the LED array. Equation 1 is applied to the graph as it is, it can be seen that the current characteristics appear.

As such, when the current stabilizing capacitor 620 is connected, all of the high frequency current components flow through the current stabilizing capacitor 620 and the constant current flows through the LED array 610 to eliminate the flicker phenomenon and also maximize the luminous flux efficiency. There is this.

When no capacitor is connected When connecting capacitor Total luminous flux [Lm] 1548 1622 Input power [W] 21.6 20.31 Luminous Efficiency [Lm / W] 73.16 79.86 LED Current Crest Factor 2.63 1.36

Table 1 shows data measured by comparing the case where the current stabilizing capacitor is not connected to the case of the LED fluorescent lamp shown in the embodiment of FIG. 6. In this embodiment, the LED fluorescent lamp was connected to the electronic ballast of the instant method, the LED array 610 was connected in parallel two pairs of 56 LED array in series. The current stabilizing capacitor 620 has a capacity of 1500 pF.

As shown in Table 1, the luminous flux efficiency when the current stabilizing capacitor is connected under the same conditions has an effect of increasing the efficiency of about 9.2% compared to the luminous flux efficiency when the current stabilizing capacitor is not connected, and the LED current Crest factor is about 43% lower from 2.63 to 1.36.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the invention as defined by the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

1, 2, 3, 4: first to fourth external connection pins
100: LED Fluorescent Lamp
131, 132, 133, 134: capacitor
141, 142, 143, 144, 145, 146, 147, 148, 149, 150: multiple diodes
300: LED Fluorescent Lamp
310: LED array 320: current stabilizing capacitor
331, 332, 333, 334: capacitive element portion
400: LED fluorescent lamp 410: LED array
441: first diode 442: second diode
500: LED fluorescent lamps 543 to 550: third to tenth diodes
531, 532, 533, and 534: first to fourth capacitors
600: LED Fluorescent Lamp
610: LED array 620: current stabilizing capacitor
631-634: 1st-4th capacitor
641 to 650: first to tenth diodes
700: LED Fluorescent Lamp
710: LED array 720: current stabilizing capacitor
731, 732, 733, 734: first to fourth capacitors
741, 742, 743, 744: first to fourth diodes
800: LED fluorescent lamp
810: LED Array
820: Current Stabilization Capacitor
831, 832, 833, 834: first to fourth capacitor
845, 846, 847, 848: fifth to eighth diodes
900: LED Fluorescent Lamp
910: LED Array
920: current stabilizing capacitor
931, 932, 933, 934: first to fourth capacitors
941 to 952: first to twelfth diodes

Claims (15)

An external connection pin including a first connection pin and a second connection pin;
An LED array comprising a plurality of LEDs connected in series;
A current stabilizing capacitor connected in parallel with the LED array;
And a capacitive element unit connected between the LED array and the external connection pin to change an impedance of a fluorescent ballast connected through the external connection pin.
The method of claim 1,
The external connection pins LED fluorescent lamp further comprises a third connection pin and the fourth connection pin.
The method of claim 2,
The capacitive element portion,
A first capacitor having one end connected to the first connection pin and the other end connected to an anode side terminal of the LED array;
A second capacitor having one end connected to the second connection pin and the other end connected to a cathode side terminal of the LED array;
A third capacitor having one end connected to the third connection pin and the other end connected to an anode side terminal of the LED array; And
A fourth capacitor having one end connected to the fourth connection pin and the other end connected to a cathode side terminal of the LED array;
LED fluorescent lamp comprising at least one of.
The method of claim 3,
Diode units connected to both ends of the LED array to form a one-way current path in the LED array
LED fluorescent lamp further comprising.
5. The method of claim 4,
The diode unit includes:
A first diode having a cathode connected to one end of the LED array and an anode commonly connected to the other end of the first capacitor and the other end of the third capacitor; And
A second diode having an anode connected to the other end of the LED array and a cathode commonly connected to the other end of the second capacitor and the other end of the fourth capacitor
LED fluorescent lamp comprising at least one of.
The method of claim 5,
Including all of the first to fourth capacitors,
The diode unit includes:
A third diode having an anode connected to one end of the first capacitor and a cathode connected to the other end of the first capacitor;
A fourth diode having a cathode connected to one end of the second capacitor and an anode connected to the other end of the second capacitor;
A fifth diode having an anode connected to one end of the third capacitor and a cathode connected to the other end of the third capacitor;
A sixth diode having a cathode connected to one end of the fourth capacitor and an anode connected to the other end of the fourth capacitor;
LED fluorescent lamp further comprises at least one of.
The method of claim 5,
Including all of the first to fourth capacitors,
The diode unit includes:
A seventh diode having an anode connected to the other end of the second capacitor and a cathode connected to one end of the first capacitor;
An eighth diode having an anode connected to one end of the second capacitor and a cathode connected to the other end of the first capacitor;
A ninth diode having an anode connected to one end of the fourth capacitor and a cathode connected to the other end of the third capacitor;
A tenth diode connected to the other end of the fourth capacitor and a cathode connected to one end of the third capacitor
LED fluorescent lamp further comprises at least one of.
5. The method of claim 4,
Including all of the first to fourth capacitors,
The diode unit includes:
A first diode having a cathode connected to one end of the LED array;
A second diode having an anode connected to the other end of the LED array;
A third diode having an anode connected to the other end of the first capacitor and a cathode connected to the anode of the first diode;
A fourth diode having an anode connected to the cathode of the second diode and a cathode connected to the other end of the second capacitor;
A fifth diode having an anode connected to the other end of the third capacitor and a cathode connected to the anode of the first diode;
A sixth diode having an anode connected to the cathode of the second diode and a cathode connected to the other end of the fourth capacitor;
A seventh diode having an anode connected to the cathode of the second diode and a cathode connected to the other end of the first capacitor;
An eighth diode having an anode connected to the other end of the second capacitor and a cathode connected to the cathode of the third diode;
A ninth diode having an anode connected to the other end of the fourth capacitor and a cathode connected to a capacitor of the fifth diode; And
A tenth diode having an anode connected to the cathode of the second diode and a cathode connected to the other end of the third capacitor
LED fluorescent lamp comprising a
5. The method of claim 4,
Including all of the first to fourth capacitors,
The diode unit includes:
A first diode having an anode connected to the other end of the first capacitor and a cathode connected to one end of the LED array;
A second diode having an anode connected to the other end of the LED array and a cathode connected to the other end of the second capacitor;
A third diode having an anode connected to the other end of the second capacitor and a cathode connected to one end of the LED array;
A fourth diode having an anode connected to the other end of the LED array and a cathode connected to the other end of the third capacitor
LED fluorescent lamp comprising a.
10. The method of claim 9,
A fifth diode having an anode connected to one end of the first capacitor and a cathode connected to the other end of the first capacitor;
A sixth diode having an anode connected to one end of the second capacitor and a cathode connected to the other end of the second capacitor;
A seventh diode having an anode connected to one end of the third capacitor and a cathode connected to the other end of the third capacitor;
An eighth diode having an anode connected to one end of the fourth capacitor and a cathode connected to the other end of the fourth capacitor;
LED fluorescent lamp further comprising.
10. The method of claim 9,
A fifth diode having an anode connected to the other end of the first capacitor and a cathode connected to one end of the first capacitor;
A sixth diode having an anode connected to the other end of the second capacitor and a cathode connected to one end of the second capacitor;
A seventh diode having an anode connected to the other end of the third capacitor and a cathode connected to one end of the third capacitor;
An eighth diode having an anode connected to the other end of the fourth capacitor and a cathode connected to one end of the fourth capacitor;
LED fluorescent lamp further comprising.
5. The method of claim 4,
Including all of the first to fourth capacitors,
The diode unit includes:
A first diode having an anode connected to the other end of the first capacitor and a cathode connected to one end of the LED array;
A second diode having an anode connected to the other end of the LED array and a cathode connected to the other end of the second capacitor;
A third diode having an anode connected to the other end of the LED array and a cathode connected to the other end of the third capacitor; And
A fourth diode having an anode connected to the other end of the fourth capacitor and a cathode connected to one end of the LED array;
LED fluorescent lamp comprising a.
The method of claim 12,
The diode unit includes:
A fifth diode having an anode connected to one end of the first capacitor and a cathode connected to the other end of the first capacitor;
A sixth diode having an anode connected to the other end of the second capacitor and a cathode connected to one end of the second capacitor;
A seventh diode having an anode connected to the other end of the third capacitor and a cathode connected to one end of the third capacitor;
An eighth diode having an anode connected to one end of the fourth capacitor and a cathode connected to the other end of the fourth capacitor;
LED fluorescent lamp further comprising. The method of claim 13,
The diode unit includes:
A ninth diode having an anode connected to the other end of the second capacitor and a cathode connected to one end of the first capacitor;
A tenth diode having an anode connected to one end of the second capacitor and a cathode connected to the other end of the first capacitor;
An eleventh diode having an anode connected to the other end of the third capacitor and a cathode connected to one end of the fourth capacitor;
A twelfth diode having an anode connected to one end of the third capacitor and a cathode connected to the other end of the fourth capacitor;
LED fluorescent lamp further comprising.
The method of claim 1,
Diode units connected to both ends of the LED array to form a one-way current path in the LED array
LED fluorescent lamp further comprising.

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