KR20150017791A - Led lighting device using ballast - Google Patents

Abstract

The present invention relates to an LED lighting device using a ballast. The LED lighting device includes: an LED unit including at least one LED device; a rectifier unit to rectify a current power signal output from the ballast; and a current driver which receives an output current of the rectifier unit to control power transferred from the ballast to the LED unit. The current driver includes: a switch to conduct or block some of output power of the ballast to the LED unit; a diode to continuously flow a current to the LED unit when the switch is turned-off; a capacitor to store or discharge the energy when the switch is turned on/off; and a transformer to electrically separate the ballast from the LED unit.

Description

{LED LIGHTING DEVICE USING BALLAST}

The present invention relates to an LED lighting apparatus using a ballast.

In recent years, light-emitting diodes (LEDs) have been increasingly used as new lighting devices in place of filament lamps and fluorescent lamps. LEDs can be driven at low voltage, have a longer lifetime, lower power consumption, faster response speed and stronger impact resistance than other lighting devices, and can be made smaller and lighter. However, since the LED is operated by a relatively low DC power source and is turned on in a manner different from the fluorescent lamp lighting, a normal LED lamp can not be used as it is in the fluorescent lamp system. In particular, in the case of an electronic ballast, since a commercially available 60 Hz AC power source is converted into a high frequency of several tens of kilohertz to provide the lamp, there has been an inconvenience to remove all existing lighting devices including a ballast to use an LED lighting apparatus. If the LED driving circuit is directly connected to the connection terminal of the conventional ballast without removing the ballast, etc., the LED driving circuit can not handle the high frequency or voltage such as the ballast properly, And the like.

Accordingly, in recent years, an LED lighting apparatus capable of directly connecting to a ballast without removing the ballast has been developed.

Korean Patent No. 10-0949087 (published on Mar. 22, 2010)

SUMMARY OF THE INVENTION The present invention has been made to solve all the problems of the prior art described above.

It is another object of the present invention to provide a ballast-compatible LED lighting device that controls power delivered from various ballasts.

It is still another object of the present invention to provide an LED lighting apparatus using a passive element of a LED lighting apparatus or a ballast capable of protecting a chip.

It is still another object of the present invention to provide an LED lighting device that increases the power consumption efficiency of power transmitted from a ballast.

It is still another object of the present invention to provide an LED lighting device which isolates a ballast and an LED to improve stability.

The LED lighting device using the ballast according to an embodiment of the present invention includes an LED unit including at least one LED element, a rectifying unit for rectifying a current power signal output from the ballast, and a rectifier for receiving an output current of the rectifying unit, A switch for conducting or blocking part of the output power of the input ballast from being transmitted to the LED unit, a diode for continuously flowing current to the LED unit when the switch is off, A capacitor for storing or releasing energy, respectively, when the switch is on or off, and a transformer for electrically separating the ballast and the LED unit.

According to the embodiment, a current sensor for sensing the magnitude of the current flowing through the LED unit; And a controller for receiving the magnitude of the current flowing from the current sensor to the LED unit and controlling on / off of the switch.

According to the embodiment, the duty of the switch is increased when the current flowing through the LED portion is larger than the predetermined current value, and the duty of the switch is decreased when the current is smaller than the predetermined current value.

According to an embodiment, a first connection terminal CT1 having a first electrode and a second electrode and receiving power from the ballast; And a second connection terminal (CT2) having a third electrode and a fourth electrode and receiving power from the ballast, wherein the rectification section includes a first filament capacitor connected in parallel with the first electrode and the second electrode, A first rectifying section including a bridge diode of the first rectifying section; And a second rectification part including a second filament capacitor and a plurality of bridge diodes connected in parallel with the third electrode and the fourth electrode.

According to an embodiment, the transformer may include an auxiliary winding for sensing a voltage applied to the LED portion.

According to an embodiment of the present invention, the apparatus may further include a filter unit for smoothing the output signal of the current driving unit and transmitting the smoothed output signal to the LED unit.

According to an embodiment of the present invention, a light emitting device includes an LED portion including at least one LED element, a rectifying portion for rectifying a current power signal output from the ballast, and a current driving portion for receiving an output current of the rectifying portion and controlling power transmitted from the ballast to the LED portion The current driving unit includes a switch for conducting or blocking part of the output power of the input ballast to be transmitted to the LED unit, a diode for allowing the current to flow continuously to the LED unit when the switch is in the OFF state, And a transformer that stores or emits energy when the switch is on or off and senses a voltage applied to the LED unit.

According to an embodiment, the transformer may include a clamping circuit for clamping a voltage proportional to the voltage applied to the LED portion.

According to an embodiment, the clamping circuit can clamp the negative voltage applied to the secondary coil of the transformer when the switch is on.

According to the embodiment of the present invention, it is possible to provide an LED lighting apparatus compatible with a conventional ballast.

According to the embodiment of the present invention, it is possible to provide a compatible LED lighting device for a ballast that controls power transmitted from various ballasts.

According to the embodiment of the present invention, it is possible to provide an LED lighting apparatus using a passive element of a LED lighting apparatus or a ballast capable of protecting a chip.

According to the embodiment of the present invention, it is possible to provide an LED lighting device which increases the power consumption efficiency of the power transmitted from the ballast.

According to the embodiment of the present invention, it is possible to provide an LED lighting device in which stability is enhanced by isolating the ballast and the LED portion.

1 is a circuit diagram of an LED lighting device using a ballast.
2 is a block diagram of an LED lighting apparatus using a ballast according to an embodiment of the present invention.
3 is a circuit diagram of an LED lighting apparatus using a ballast according to an embodiment of the present invention.
FIG. 4A is a circuit diagram showing a connection with a choke magnetic ballast using a rectifying part having both ends of the lamp short-circuited to two terminals, FIG. 4B is a view showing a connection with a rapid start magnetic ballast using a rectifying part where both ends of the lamp are short- FIG. 4C is a circuit diagram showing a connection with a rapid start electronic ballast using a rectifying part in which a resistance corresponding to a filament is inserted, and FIG. 4D is a circuit diagram showing a connection with a rapid start electronic ballast, FIG. Fig. 4E is an equivalent circuit of Fig. 4D.
5 is a circuit diagram of a rectifying unit according to an embodiment of the present invention.
6A to 6D are circuit diagrams illustrating various implementations of the rectifying unit according to the embodiment of the present invention.
7A to 7D are circuit diagrams of a LED lighting apparatus using a rectifying unit according to an embodiment of the present invention and connection diagrams with various ballasts.
8A is an LED lighting device including a current buck converter, and Fig. 8B is an LED lighting device including a current boost converter.
9 is a circuit diagram of an LED lighting apparatus according to another embodiment of the present invention.
10 is a circuit diagram of an LED lighting apparatus according to another embodiment of the present invention.
11A is a waveform diagram of a circuit and a specific signal of a current driver including a current boost converter, and FIG. 11B is a waveform diagram of a current driver circuit and a specific signal using a transformer.
12A and 12B are waveform diagrams of voltage of an LED lighting device using a ballast including a boost converter according to an embodiment of the present invention and an output node according to ON / OFF of a switch.
13A and 13B are waveform diagrams of a secondary winding voltage of an LED lighting apparatus and a transformer using a transformer using a transformer according to an embodiment of the present invention.
FIG. 14A is a circuit diagram schematically showing a circuit in which the auxiliary winding is added to the transformer of FIG. 10, FIG. 14B is a circuit diagram showing the switch when the switch is in the ON state, and FIG.

The following detailed description of the invention refers to the accompanying drawings, which illustrate, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different, but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with an embodiment. It is also to be understood that the position or arrangement of the individual components within each disclosed embodiment may be varied without departing from the spirit and scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is to be limited only by the appended claims, along with the full scope of equivalents to which such claims are entitled, if properly explained. In the drawings, like reference numerals refer to the same or similar functions throughout the several views.

[Preferred Embodiment of the Present Invention]

The principle of the LED lighting apparatus using the ballast applied to the LED lighting apparatus using the ballast according to the embodiment of the present invention will be briefly described.

1 is a view showing an LED lighting apparatus using a ballast.

Referring to FIG. 1, the LED lighting apparatus receives AC power from the power supply units 31 and 33 through the power input terminals 15 and 16. The rectifying unit 35 receives power from the power source units 31 and 33, performs full wave rectification, and transmits the rectified power to the filter unit 39. The filter unit 39 smoothes the full-wave rectified voltage from the rectifying unit 35 into a direct-current voltage and transmits the smoothed voltage to the driving unit 41. The driving unit 41 includes a buck-boost converter and controls the voltage and the current supplied to the LED by using the DC voltage outputted from the filter unit 39 to be constant.

However, the LED lighting apparatus shown in Fig. 1 has a structure for controlling only the electric power to be transmitted to the LEDs without consideration of the output of the ballast using a voltage converter. When the output power of the ballast is larger than the power required by the LED, Energy is accumulated in the capacitor of the unit 39 and the voltage continuously increases. More specifically, if the current input from the ballast is increased for some reason in a steady state LED lighting device, the amount of charge accumulated in the capacitor of the filter unit 39 increases, so that the voltage across the capacitor of the filter unit 39 Is increased. Since the LED lamp consumes a certain amount of electric power, the amount of electric current that is transmitted from the filter unit 39 to the LED lamp becomes smaller than in the normal state. Therefore, since the amount of current output from the filter unit 39 is greater than the current input to the filter unit 39, the voltage across the capacitor of the filter unit 39 is increased, A voltage exceeding the allowable value is applied to the filter section 39 made of a capacitor, thereby causing a problem that the passive element or the chip of the LED lighting apparatus is damaged. That is, there is a problem that the lifetime of the LED lighting apparatus is shortened. In addition, it is not compatible with various ballasts of different standards, and stability due to change of power source is weak. Particularly, the ballasts such as fluorescent lamps and halogen lamps, which are widely used at present, have various problems to be directly connected to each other due to different operation method of the LED elements.

The LED lighting apparatus using the ballast according to the embodiment of the present invention described later can overcome the disadvantages of such LED lighting apparatus.

Hereinafter, an LED lighting apparatus using a ballast according to an embodiment of the present invention will be described.

2 is a block diagram of an LED lighting apparatus using a ballast according to an embodiment of the present invention.

2, an LED lighting apparatus using a ballast according to an exemplary embodiment of the present invention includes an LED unit 130 including at least one LED device, a rectifier unit 100 for rectifying a current power signal output from the ballast 10, And a current driver 110 receiving the output signal of the rectifier 100 and controlling the power transmitted from the ballast 10 to the LED unit 130.

The LED lighting apparatus 200 using the ballast according to the embodiment of the present invention may further include a filter unit 120 that smoothes the output signal of the current driving unit 110 and transmits the smoothed output signal to the LED unit 130 .

The ballast according to the embodiment of the present invention may be a ballast used for a fluorescent lamp, a halogen lamp or the like.

3 is a circuit diagram of an LED lighting apparatus using a ballast according to an embodiment of the present invention.

3, the rectifying unit 100 of the LED lighting apparatus 200 using the ballast according to the embodiment of the present invention includes a first rectifying unit 101 for rectifying a current power input from the ballast 10, 2 rectification part 102. [ The current driver 110 receives the output current of the rectifier 100 and controls power transmitted from the ballast 10 to the LED unit 130. The current driving unit 110 transmits a current having a magnitude larger than the magnitude of the output current of the rectifying unit 100 to the LED unit 130. The current driver 110 may include a current boost converter including a capacitor 111, a diode 112, an inductor 113 and a switch 114. Diode 112 may be a switching element that operates complementarily to switch 114. The filter unit 120 may be implemented as a capacitor unit 121 including at least one capacitor, and the LED unit 130 may include at least one LED device.

Hereinafter, the rectifying unit 100 of the LED lighting apparatus 200 using the ballast according to an embodiment of the present invention will be described.

The LED lighting apparatus to which the rectifying unit 100 according to the embodiment of the present invention is applied will be briefly described.

4A shows a connection with a choke magnetic ballast using a rectifying part having both ends of the lamp short-circuited to two terminals, and FIG. 4B shows a connection with a rapid start magnetic ballast using a rectifying part in which both ends of the lamp are short- , FIG. 4C shows the connection with the rapid start electronic ballast using the rectifying part with the resistance corresponding to the filament inserted therein, and FIG. 4D shows the connection with the rapid start electronic ballast in which the rectifying part is inserted at each end of the lamp. Fig. 4E is an equivalent circuit of Fig. 4D.

As shown in Fig. 4A, the choke type ballast 11 uses a choke (starter) that changes to an open or short-circuited state at a certain point in time to obtain a discharge voltage. The choke magnetic ballast 11 using the general rectifier 21 does not separate the starter path which is the auxiliary path 3 necessary for discharging. Therefore, since the voltage source path which is the main path 2 and the starter path which is the auxiliary path 3 are not separated from each other, it is possible to cause malfunction of choke in which open or short-circuit alternately occurs.

4B, the rapid start magnetic ballast 12 preheats the filament to the first and second transformers T1 and T2 and utilizes the first and second transformers T1 and T2 to adjust the characteristics of the current source . However, if the main path 2 and the auxiliary path 3 are short-circuited, an overcurrent may be generated by the transformer, which may cause a problem in stability and reduce the efficiency of the ballast.

As shown in FIG. 4C, in the case of the rapid start electronic ballast 13, when about 3? Resistors R1 to R4, which are resistance values corresponding to filaments, are inserted into the rectifying unit 23, All the problems caused by the short circuit of (3) can be solved. However, power consumption occurs in the resistors R1 and R4 of the current source path which is the main path 2, thereby reducing the efficiency of the lighting apparatus.

On the other hand, when the rectifying section 24 having the first and second rectifying sections at both ends of the LED lamp is applied to the magnetic ballast, the problem caused by the short circuit due to the starter or the transformer path being disconnected is solved. However, if the rectifying section 24 having the first and second rectifying sections is applied to the rapid-start electronic ballast 13 as shown in Fig. 4D, the parallel capacitors Cp included in the resonator of the electronic ballast 13 The resonance characteristic of the ballast 13 is changed, so that the operation of the normal ballast is impossible. Referring to FIG. 4E, the rectifying unit 24 transmits the power received from the stabilizer 13 to the driving unit or the LED unit, but it is impossible to transmit power from the driving unit or the LED unit to the rectifying unit 24. Therefore, although the effect of isolating the auxiliary path 3 is generated, it is preferable in the magnetic ballast, but in the electronic ballast 13, the auxiliary path 3 is opened and the Cp is removed, so that the ballast malfunctions due to the resonator change There is concern to cause.

On the other hand, although not shown in FIGS. 4A to 4E, some program start electronic ballasts may occasionally turn on later or not at all because no voltage is sensed in the filament during short-circuiting of the filament.

Fig. 5 shows a rectifying part according to an embodiment of the present invention which can solve the problems of the rectifier shown in Figs. 4A to 4E.

3 and 5, the bridge diodes D11 to D14 of the first rectification part 101 and the bridge diodes D21 to D24 of the second rectification part 102 are connected to the first connection terminal CT1) and the second connection terminal CT2, the same wiring (connection direction of diodes, etc.). This is in order to cope with arbitrary connection between connection terminals or between electrodes in an ordinary lighting device. The rectifying unit 100 according to the embodiment of the present invention may include a first electrode J1, a second electrode J2, a third electrode J3, and a fourth electrode J4.

3 and 5, when the ballast, which is an AC power source having four or two electrodes, is inputted through the first to fourth electrodes J1 to J4, the first rectifying part 101 and the second rectifying part 101, The current driver 102 outputs the full-wave rectified voltage to the current driver 110. It is preferable that the bridge diode combination D11 to D14 and D21 to D24 use a high frequency diode for processing AC power having a frequency several hundred times as much as the commercial power output from the ballast.

In addition, the rectifying unit 100 according to the embodiment of the present invention removes the auxiliary path for preheating the starter or filament of the ballast when connected to the magnetic ballast, and a circuit for connecting the auxiliary path when connected to the electronic ballast . The rectifying unit 100 according to the embodiment of the present invention is configured such that the first impedance Z1 (f) is connected in parallel to the first electrode J1 and the second electrode J2, And a second impedance Z2 (f) are connected in parallel to the fourth electrode J4. The first impedance Z1 (f) and the second impedance Z2 (f) may vary depending on the input frequency f.

6A to 6D show a specific circuit form of the rectifying unit 100 according to the embodiment of the present invention.

Referring to FIG. 6A, the first impedance Z1 (f) and the second impedance Z2 (f) may be implemented by a first filament capacitor Cf1 and a second filament capacitor Cf2, respectively. Therefore, the first and second filament capacitors Cf1 and Cf2 are opened at a low frequency and short-circuited at a high frequency. Since the magnetic ballast uses the low frequency signal of about 50 to 60 Hz and the electronic ballast uses the high frequency signal of 20 kHz or more, the auxiliary path is opened in the magnetic ballast using the low frequency signal, and in the electronic ballast using the high frequency signal, . It is preferable that the capacitance of the first and second filament capacitors Cf1 and Cf2 is sufficiently larger than the capacitance of the parallel capacitor Cp of the electronic ballast. Therefore, the impedance due to the first and second filament capacitors Cf1 and Cf2 is negligible when viewed from the auxiliary path. It is preferable that the first and second filament capacitors Cf1 and Cf2 have a value of 30 nF or more because the capacitance of the parallel capacitor Cp of the conventional electronic ballast is about 5 nF.

Referring to FIG. 6B, the first impedance Z1 (f) and the second impedance Z2 (f) may be implemented by a first switch SW1 and a second switch SW2, respectively.

The first and second switches SW1 and SW2 operate to open both ends of the switch when the magnetic ballast is connected and to short both ends of the switch when the electronic ballast is connected. Therefore, if the ON / OFF of the first and second switches SW1 and SW2 is set in advance according to the type of the ballast, it is compatible with both the magnetic ballast and the electronic ballast. Further, the rectifying section may further include a circuit for sensing the output frequency of the ballast to change the state of the switch. The ON / OFF operation of the first and second switches SW1 and SW2 can be controlled by the control voltage Vcon. Meanwhile, the first and second switches SW1 and SW2 may be transistors for fast switching, and may be specifically a field effect transistor (MOSFET) or a bipolar junction transistor (BJT).

Referring to FIG. 6C, the first impedance Z1 (f) and the second impedance Z2 (f) may be implemented by a first variable resistor VR1 and a second variable resistor VR2, respectively.

When the magnetic ballast is connected, the first and second variable resistors VR1 and VR2 have a very large resistance value so that both ends of the variable resistance are close to the open state, and when the electronic ballast is connected, And has a very small resistance value. Therefore, if the resistance values of the first and second variable resistors VR1 and VR2 are set in advance according to the type of the ballast, it is compatible with both the magnetic ballast and the electronic ballast. Further, the rectifying section may further include a circuit for sensing the output frequency of the ballast to change the resistance value of the variable resistor. The resistance values of the first and second variable resistors VR1 and VR2 can be realized by a resistor and a switch. This switch can be controlled by the control voltage Vcon.

Referring to FIG. 6D, the first impedance Z1 (f) and the second impedance Z2 (f) may be implemented by a first resonator and a second resonator, respectively.

6D, the first resonator may be a band-pass filter including two inductors Lf1 and Lf2 and one capacitor Cf1, and the second resonator may include two inductors Lf3 and Lf4, And may be a band-pass filter including one capacitor Cf2.

When the magnetic ballast is connected, the passband frequency is set such that both ends of the capacitors Cf1 and Cf2 are opened in the first resonator and the second resonator. When the electronic ballast is connected, the capacitors Cf1 and Cf2 are short- The band frequency is set. Specifically, since the electronic ballast operates at 30 to 75 kHz, it can be realized as a low-selectivity LC resonator with low impedance in the 30 to 75 kHz band. A method of varying the capacitors Cf1 and Cf2 of the first and second resonators may also be used to adjust the passband. The variable of the capacitor can be implemented by a plurality of capacitors and switches.

In other words, the rectifying unit 100 according to the embodiment of the present invention includes two rectifying units 101 and 102, and when the magnetic ballasts are connected, the rectifying units 101 and 102 are opened And when the electric ballast is connected, the main path and the auxiliary path are short-circuited. In addition, the circuit constituting the first and second impedances Z1 (f) and Z2 (f) in FIGS. 6A and 6D is not necessarily implemented independently, but may be implemented by including two or more circuits.

7A to 7D are block diagrams of an LED lighting device including a rectifying part according to an embodiment of the present invention.

As shown in Figs. 4A and 7A, when the conventional rectifying part 21 is applied to the choke magnetic ballast 11, the starter path 3 required for the voltage discharge is not separated from the current source path 2 The first and second impedances Z1 (f) and Z2 (f) are opened because the rectifying section 100 according to the embodiment of the present invention receives a low frequency signal of the magnetic ballast. Therefore, the possibility of malfunction is eliminated since the starter path 3 is isolated.

As shown in Figs. 4B and 7B, when the current source path 2 and the auxiliary path 3 are short-circuited, a general current rectifier 22 is applied to the rapid start magnetic ballast 12, Can cause problems and reduce the efficiency of the ballast. However, since the rectifier 100 according to the embodiment of the present invention receives the low-frequency signal of the magnetic ballast, the magnitude of the filament current approaches zero. Therefore, it is possible to solve the problem of stability of the LED lighting apparatus and the problem of reduction of the ballast efficiency.

As shown in Figs. 4C and 7C, when the general rectifying part 23 is applied to the rapid start electronic ballast 13, most of the problems caused by the short circuit are solved, but the power in the resistance of the current source path 2 Thereby reducing the efficiency of the lighting apparatus. However, since the rectifying unit 100 according to the embodiment of the present invention receives the high frequency signal of the electronic ballast, the first and second impedances Z1 (f) and Z2 (f) are short- There is no loss of power and the efficiency of the lighting apparatus can be increased.

On the other hand, in the case of the instant-start electronic ballast 14 having a two-terminal output, as shown in Fig. 7 (d), the rectifying unit 100 according to the embodiment of the present invention is influenced by a short- It is also compatible with 2-terminal output ballast because it does not receive.

In summary, the rectifying unit 100 according to the embodiment of the present invention is compatible with both the electronic ballast and the magnetic ballast, and has a small power consumption.

Next, the current driving unit 110 of the LED lighting apparatus 200 using the ballast according to the embodiment of the present invention will be described.

As described briefly above, the LED lighting device using the ballast shown in FIG. 1 uses a voltage converter such as a voltage boost converter or a voltage buck converter to supply a constant power to the LED unit. However, since the power supplied from the ballast to the LED lighting device is a current source, not a voltage source, there is a limit in controlling power using a voltage converter. Therefore, in the LED lighting apparatus using the ballast shown in FIG. 1, a filter unit for converting a current source input from the ballast into a voltage source is connected between the rectifying unit and the voltage converter. In this voltage converter, when the amount of current input from the ballast increases, the amount of current output to transmit a constant power to the LED unit is reduced, so that the voltage applied to the capacitor of the filter unit is further increased. As a result, there is a problem that the voltage applied to the capacitor of the filter portion is excessively increased.

In order to solve the above problem, the current driving unit 110 of the LED lighting device using the ballast according to the embodiment of the present invention uses a current boost converter for controlling the current power applied from the rectifying unit 100 .

As shown in FIG. 3, the current driver 110 receives the rectified signal from the rectifier 100, and controls power transmitted from the ballast to the LED unit. That is, the ballast output is used to output the rated voltage and current signals for the LED unit 130. The current driving unit 110 includes a first terminal N1 and a second terminal N2 and receives the current signal rectified by the rectifying unit 100 through the first terminal N1 and the second terminal N2, . The current driver 110 may include a current boost converter that receives current power from the rectifier 100 and supplies current power to the LED 130. The current driving unit 110 includes a switch 114 for conducting or blocking part of the inputted ballast output power from being transmitted to the LED unit, a diode 112 for continuously flowing current to the LED unit when the switch is in the off state, And a capacitor 111 and an inductor 113, respectively, which store or emit energy when the switch is on or off. The switch 114 may be implemented as a transistor. In the embodiment of the present invention, the current is continuously supplied to the LED unit 130 by using the diode 112. However, the device in which the current flows continuously through the LED unit 130 must be a diode 112), and a switching element that operates complementarily with the switch 114 is sufficient. As such a switching element, a field effect transistor (MOSFET) or a bipolar junction transistor (BJT) or the like may be used.

3, the capacitor 111 is connected between the first terminal N1 and the second terminal N2 and the diode 112 is connected between the first terminal N1 and the first terminal N1, And is connected to one end of the switch 114 and one end of the LED unit 130. The inductor 113 has one end connected to the first terminal N1 and the other end connected to the positive or negative terminal of the LED unit 140. The switch 114 has one end connected to the second terminal N2, And may be connected to the positive or negative terminal of the LED unit 140.

FIG. 8A shows an LED lighting device using a ballast including a current buck converter, and FIG. 8B shows an LED lighting device using a ballast including a current boost converter according to an embodiment of the present invention.

The current buck driver 109 using the current buck converter shown in FIG. 8A and the current driver 110 including the current boost converter shown in FIG. 8B basically transmit the power to the load by receiving the current source. However, the current buck driver 109 shown in FIG. 8A controls the magnitude of the current delivered to the lower stage to be smaller than the magnitude of the current input to the current buck driver 109. Therefore, in order to transmit a predetermined amount of power to the lower end, the magnitude of the voltage transmitted to the lower end increases. When the lower end is an LED element, a high voltage of 60 V or more may be applied to the LED element. In some areas such as the United States, it is necessary to use tempered glass in order to secure stability when a voltage of 60 V or more is applied to the LED lighting device, thereby lowering the transparency and thus lowering the light efficiency. However, in contrast to the current buck driver 109 described above, the current driving unit 110 including the current boost converter increases the current applied to the LED device, so that the magnitude of the voltage applied to the LED device is reduced. Therefore, there is an effect that the problem of the current buck driver 109 described above does not occur. That is, the current driving unit 110 including the current boost converter according to the embodiment of the present invention has advantages of stability against voltage, low cost, and excellent light efficiency when applied to an illumination device than the current buck driving unit 109 have. In addition, the ballast is a non-ideal current source having a parallel capacitor Cp. Therefore, the current buck structure having the current source input and the parallel switching may discharge the capacitance of the parallel capacitor Cp, thereby reducing the efficiency of the lighting device. Therefore, a current boost structure in which the switches are not connected in parallel to the current source input Is advantageous.

Referring to FIG. 3, the filter unit 120 includes a capacitor to smooth the voltage and current controlled by the current driving unit 110, and provides the smoothed voltage and current to the LED unit 130. The filter unit 120 may include a capacitor unit having one or more capacitors. The filter unit 120 is designed to have a sufficient time constant for smoothing the power source including the high frequency ripple supplied from the current driving unit 110 so that the current value can be prevented from flickering due to the change .

The LED unit 130 includes LED elements that emit light using voltage and current supplied from the filter unit 120. The LED elements included in the LED unit 130 are connected in parallel or in series and are lighted.

9 is a circuit diagram of an LED lighting apparatus using a ballast according to an embodiment of the present invention, which further includes a control unit for controlling a current flowing through the LED unit.

9, the current driving unit 110 includes a capacitor 111, a diode 112, an inductor 113, and a switch 114 of FIG. 3, And a current sensor 116 that senses a current flowing through the LED unit 130 and transmits the detected current to the controller 115.

That is, by controlling the duty of the switch 114 of the current driving unit 110 for various ballasts having different device values, the magnitude of the power consumed by the LED unit 130 can be controlled to be constant . Specifically, the control unit 115 receives the magnitude of the current flowing from the current sensor 116 to the LED unit 130, and controls on / off of the switch 114. The duty of the switch 114 is increased when the current flowing through the LED unit 130 is larger than the predetermined current value and the duty of the switch is decreased when the current flowing through the LED unit 130 is smaller than the predetermined current value, Voltage and current. Accordingly, since the constant power can be supplied to the LED unit 130 through on / off control of the switch 114 irrespective of the device characteristics of the ballast, it is advantageous to be compatible with various ballasts. In addition, since the power required by the LED unit 130 is supplied, the output power of the ballast does not match with the power consumed by the LED lighting apparatus, so that energy is accumulated in the filter unit 120 or LED brightness is not controlled The passive elements such as the filter unit 120 and the chips can be prevented from being damaged.

Further, the rectifying unit 100 according to the embodiment of the present invention includes two rectifying units each having a filament capacitor, and is compatible with all the ballasts of the magnetic type and the electronic type.

10 shows a current driver according to another embodiment of the present invention.

Referring to FIG. 10, the current driver 131 of the LED lighting device 201 according to another embodiment of the present invention includes a transformer circuit.

11A shows a waveform of a specific signal of the current driver including the current boost converter, and FIG. 11B shows a waveform of a specific signal of the current driver using the transformer.

Referring to Figs. 11A and 11B, when the switch is in the OFF state, the current and the voltages ic and Vc applied to the capacitors C1 and C2 and the voltages (ic and Vc) applied to the capacitors C1 and C2 It can be seen that the current and voltage (ic, Vc) have the same waveform.

10, the current driving unit 131 including the transformer 212 controls the electric power transmitted from the ballast 10 to the LED unit 130. As shown in FIG. The current driving part 131 of the LED lighting device 201 according to the embodiment of the present invention is configured such that a current having a magnitude larger than the magnitude of the output current of the rectifying part 100 or a current having a smaller magnitude To the LED unit 130. [0050] That is, the magnitude of the current transmitted to the LED unit 130 can be controlled according to the turns ratio of the first and second windings of the transformer 212. The current driving unit 131 according to the embodiment of the present invention includes a switch 214 for conducting or blocking part of the output power of the input ballast 10 to the LED unit 130, A capacitor 211 for storing or releasing energy when the switch 214 is on or off and a capacitor 211 for storing the energy when the switch 214 is turned on or off, And a transformer 212 that electrically isolates the portion 130.

Since the current driver 131 according to the embodiment of the present invention uses the transformer 212 to isolate the ballast 10 as the primary side of the transformer 212 from the LED 130 as the secondary side, 201) can be increased. The LED lighting apparatus 201 including the current driving unit 131 using the transformer may also adjust the duty of the switch 214 to supply the desired rated voltage and current to the LED unit 130. [

Meanwhile, according to another embodiment of the present invention, the LED lighting device using the ballast may sense an abnormal condition in which the LED unit is opened or opened by sensing the voltage of the LED unit.

12A and 12B are waveform diagrams of voltage of an LED lighting device using a ballast including a boost converter according to an embodiment of the present invention and an output node according to ON / OFF of a switch.

12A, when the switch SW is in the off state, the diode D1 is conductive, so that the voltage Vo of the node at which power is input to the LED unit, that is, the output node of the ballast power, And the voltage (Vc) of the first capacitor (C1). Therefore, the output node voltage Vo = the first capacitor voltage Vc + the LED sub-voltage VLOAD. On the other hand, when the switch SW is turned on, one end of the LED portion is grounded, so that the output node voltage Vo becomes equal to the voltage VLOAD of the LED portion.

Referring to FIG. 12B, it can be seen that when the switch is off, the voltage Vo of the output node is Vc + VLOAD, and when the switch is on, it is lowered to VLOAD. At this time, the first capacitor voltage Vc is considerably larger than the voltage VLOAD of the LED portion. Therefore, in order to sense the output node voltage Vo, it is necessary to scale the output node voltage Vo with a resistor divider or the like. In this case, it is difficult to sense the output node voltage Vo very accurately . For example, assuming that the output node voltage Vo is 40 volts in the steady state and the first capacitor voltage Vc is 320 volts, sensing that the output node voltage Vo is + 20% (Vo) can rise to 320 + 48 = 368V. Therefore, in order to sense the output node voltage Vo using an IC of 3.3 V, it is necessary to divide it by approximately 1/112 (approximately 368 / 3.3). Therefore, the LED sub voltage (VLOAD) sensed when the switch is on is 40V / 112 = 0.36V, and 48V / 112 = 0.43V when the LED sub voltage (VLOAD) is increased by 20% Is only 70 mV, so it is difficult to perform fine sensing in order to distinguish between normal operation and abnormal operation.

In order to solve the difficulty of sensing, the current driving unit of the LED lighting device using the ballast according to another embodiment of the present invention stores or emits energy when the switch SW is on or off, And a transformer T1 for sensing a voltage to be applied.

13A and 13B are waveform diagrams of a secondary winding voltage of an LED lighting apparatus and a transformer using a transformer using a transformer according to an embodiment of the present invention.

Referring to FIG. 13A, the current driver of the LED lighting device according to another embodiment of the present invention includes a transformer.

13A, when the switch is in the OFF state, the voltage VL1 of the first winding of the transformer T1 is equal to the LED sub-voltage VLOAD. At this time, the voltage VT1 of the second winding of the transformer has a voltage proportional to the winding ratio n. On the other hand, when the switch is on, the first coil voltage VL1 of the transformer T1 becomes a value obtained by subtracting the first capacitor voltage Vc from the LED sub-voltage VLOAD.

As shown in FIG. 13B, when the voltage Vo of the output node is nVLOAD when the switch is in the OFF state and when the switch is ON, the voltage Vo of the output node is lowered to -n (Vc-VLOAD). At this time, the first capacitor voltage Vc is considerably larger than the voltage VLOAD of the LED portion. Here, as shown in Fig. 13B, the voltage Vo of the output node when the switch SW is in an ON state has a negative value. Therefore, the clamping circuit can be used to clamp the voltage Vo of the output node to obtain the sensing voltage Vs. Therefore, when the output node voltage Vo is clamped using the clamping circuit, the sensing voltage Vs is 0 when the switch is off, and when the switch is on, the first clamping resistor Rc1 and the second clamping resistor < Has a value proportional to nVLOAD according to the resistance ratio of Rc2. Therefore, it is only necessary to monitor the nVLOAD voltage level. Therefore, there is no need to sense the voltage Vo of the output node with a very high resolution in order to sense the voltage of the LED portion, so there is an effect that the open or short-circuit state of the LED portion can be sensed without a separate circuit or device.

14A is a circuit diagram briefly showing a circuit in which the auxiliary winding is added to the transformer 212 of Fig. 10 described above. Fig. 14B is a circuit diagram showing a state when the switch SW is on, And the switch SW is in an off state.

10 and 14A, the transformer 212 shown in FIG. 10 may include a primary winding T1, a secondary winding T2, and an auxiliary winding T3. And the voltage VLOAD applied to the LED can be sensed through the auxiliary winding T3.

Referring to FIG. 14B, the LED lighting device using the ballast includes an ideal primary winding T1, a secondary winding T2, an auxiliary winding T3, and a magnetizing inductor T1_m connected in parallel to the primary winding T1 , magnetizing inductor). When the switch SW is in the ON state, current flows through the magnetizing inductor T1_m and energy is stored, and the voltage applied to the primary winding T1 is the first capacitor voltage Vc. At this time, since the voltage applied to the secondary side is applied with a reverse voltage to the diode D1, the diode D1 can not be turned on.

Referring to FIG. 14C, when the switch SW is off, the current of the magnetizing inductor T1_M on the primary side flows to the ideal transformers T1, T2, and T3. Therefore, the voltage is applied to the secondary winding T2 as in the polarity shown in Fig. 14B, and therefore the diode D1 is turned on. At this time, the voltage of the LED becomes equal to the voltage applied to the secondary winding (T2), and the voltage across the tertiary winding is determined by the turns ratio between the secondary winding and the tertiary winding. So that the voltage of the LED can be sensed.

As described above, the LED lighting device using the ballast for transmitting energy using the transformer can sense the open or short-circuited state of the LED by sensing the voltage applied to the LED as well as transmitting the energy using the transformer.

As described above, according to the embodiment of the present invention, the LED lighting device using the ballast can be easily implemented. That is, the passive element or the chip of the lighting apparatus can be protected by transmitting the electric power required from the ballast through the current driver through the LED unit. In addition, it is possible to supply a rated voltage and current to the LED section and reduce the burden imposed on other passive elements or chips. Accordingly, it is compatible with any conventional ballast according to the power control of the controller, and stable power supply and circuit element protection are possible.

The features, structures, effects and the like described in the embodiments are included in at least one embodiment of the present invention and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects and the like illustrated in the embodiments can be combined and modified by other persons skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

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 taken by way of illustration, It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

1: current source
2: Main path
3: Auxiliary path
10: Ballast
11: Choke magnetic ballast
12: Rapid-start magnetic ballast
13: Rapid Start Electronic Ballast
14: Instant start electronic ballast
21, 22, 23, 24:
100: rectification part
101: first rectification part
102: second rectifying part
109: Current buck driver
110: Current driver
111: Capacitor
112: diode
113: Inductor
114: switch
115:
116: Current sensor
120:
121:
130: LED section
131:
200, 201: LED lighting device
211: Capacitor
212: Transformer
213: Diode
214: switch

Claims (9)

An LED comprising: at least one LED element;
A rectifier for rectifying a current power signal output from the ballast; And
A current driver for receiving an output current of the rectifying unit and controlling power transmitted from the ballast to the LED unit,
Lt; / RTI >
The current driver includes:
A switch for conducting or blocking part of the output power of the input ballast from being transmitted to the LED unit,
A diode for allowing a current to flow continuously to the LED unit when the switch is in an OFF state,
A capacitor for storing or releasing energy, respectively, when the switch is on or off, and
And a transformer for electrically isolating the ballast from the LED unit.
LED lighting device using ballast. The method according to claim 1,
A current sensor for sensing a magnitude of a current flowing through the LED unit;
Further comprising a control unit for receiving the magnitude of a current flowing from the current sensor to the LED unit and controlling ON / OFF of the switch,
LED lighting device using ballast. 3. The method of claim 2,
Wherein,
Wherein the duty of the switch is increased when the current flowing through the LED unit is larger than a predetermined current value and the duty of the switch is decreased when the current is smaller than a predetermined current value. The method according to claim 1,
A first connection terminal (CT1) having a first electrode and a second electrode to receive power from the ballast; And
And a second connection terminal (CT2) having a third electrode and a fourth electrode for receiving power from the ballast,
The rectifying unit includes:
A first rectifying part including a first filament capacitor and a plurality of bridge diodes connected in parallel with the first electrode and the second electrode; And
And a second rectification part including a second filament capacitor and a plurality of bridge diodes connected in parallel with the third electrode and the fourth electrode,
LED lighting device using ballast. The method according to claim 1,
Wherein the transformer comprises:
And an auxiliary winding for sensing a voltage applied to the LED unit.
LED lighting device using ballast. 6. The method according to any one of claims 1 to 5,
And a filter unit for smoothing the output signal of the current driving unit and transmitting the smoothed output signal to the LED unit.
LED lighting device using ballast. An LED comprising: at least one LED element;
A rectifier for rectifying a current power signal output from the ballast; And
A current driver for receiving an output current of the rectifying unit and controlling power transmitted from the ballast to the LED unit,
Lt; / RTI >
The current driver includes:
A switch for conducting or blocking part of the output power of the input ballast from being transmitted to the LED unit,
A diode for allowing a current to flow continuously to the LED unit when the switch is in an OFF state,
A capacitor for storing or releasing energy when the switch is on or off, and
A switch for storing or emitting energy when the switch is on or off and a switch for sensing a voltage applied to the LED,
/ RTI >
LED lighting device using ballast. 8. The method of claim 7,
Wherein the transformer comprises:
And a clamping circuit for clamping a voltage proportional to a voltage applied to the LED unit.
LED lighting device using ballast. 9. The method of claim 8,
The clamping circuit comprising:
And clamping a negative voltage applied to the secondary coil of the transformer when the switch is on,
LED lighting device using ballast.

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