CN102711346B - Electronic ballast with multiple outputs - Google Patents

Abstract

The invention relates to a multi-output electronic stabilizer for driving a plurality of groups of lamp tubes, which comprises an alternating current-direct current conversion circuit, a voltage stabilizing circuit and a voltage stabilizing circuit, wherein the alternating current-direct current conversion circuit converts alternating current input voltage into high-voltage direct current voltage; the first inverter circuit selectively converts the high-voltage direct-current voltage into a first alternating-current output voltage; the second inverter circuit converts the high-voltage direct current voltage into a second alternating current output voltage; an auxiliary voltage generating circuit for generating an auxiliary voltage; the control circuit selectively receives the electric energy of the auxiliary voltage according to the conducting state of the first external switch to generate a control signal to the first inverter control circuit; when the control signal generated by the control circuit is transmitted to the first inverter control circuit, the first inverter control circuit starts to operate, so that the first inverter circuit converts the high-voltage direct-current voltage into a first alternating-current output voltage. The invention can save the cost of the power element, and has the advantages of small volume, no space occupation and the like.

Description

Electronic ballast with multiple outputs

technical field

The invention relates to an electronic ballast, in particular to a multi-output electronic ballast which can selectively stop outputting part of the output voltage.

Background technique

Lighting is the basic need of human beings. In recent years, with the frequent global economic, trade and commercial activities, and the improvement of the quality of home life, lighting power consumption has also risen. The overall lighting power demand is very considerable. Currently, the most widely used lamp body is A low-pressure gas discharge lamp, also known as a fluorescent lamp or a fluorescent lamp. Therefore, if we can devote ourselves to the energy saving of this kind of low-pressure gas discharge lamp, we can save considerable electric energy. With the evolution of the times and the improvement of social living standards, ordinary lighting The drive circuit is no longer sufficient, low electromagnetic interference, high efficiency, high power factor, no flicker and light weight, high-quality lighting, energy-saving electronic ballasts have become the mainstream of lighting equipment in recent years.

The circuit structure of this type of electronic ballast is slightly complicated. The known single-output electronic ballast includes an AC-DC conversion circuit and an inverter circuit. DC voltage, and then the inverter circuit converts the high-voltage DC voltage into a high-frequency AC output voltage to drive the lamp. Among them, the AC-DC conversion circuit can include a power factor correction (PFC) function to improve the power of the electronic ballast factor, and the inverter circuit achieves high-efficiency, flicker-free, high-quality lighting by adjusting the operating frequency.

Now in places with large spaces, such as warehouses, a large number of fluorescent lamps are used as indoor lighting. During the daytime, when the outdoor light is sufficient or when there is no personnel working indoors, some fluorescent lamps can be selectively turned off, for example, one of the two sets of lamp tubes can be turned off to avoid wasting energy and achieve the purpose of energy saving.

In order to achieve the dimming technology that can selectively turn off some lamps, the current practice is to provide a multi-output electronic ballast to drive two sets of lamps (the first set of lamps and the second set of lamps). A known multi-output electronic ballast includes a first AC-DC conversion circuit, a second AC-DC conversion circuit, a first inverter circuit and a second inverter circuit, wherein the first AC-DC conversion circuit has A first input terminal and a first output terminal, the first output terminal is electrically connected to the first inverter circuit, and the power loop formed by the first AC-DC conversion circuit and the first inverter circuit is used to drive the first similarly, the second AC-DC conversion circuit has a second input terminal and a second output terminal, the second output terminal is electrically connected to the second inverter circuit, and the second AC-DC conversion circuit and The power loop formed by the second inverter circuit is used to drive the second group of lamp tubes.

In order to allow the user to control whether the two sets of lamps emit light, a first switch is connected in series at the first input end, and a second external switch is connected in series at the second input end, and the input is determined by the conduction of the external switch. Whether the voltage is respectively introduced into the first or the second AC-DC conversion circuit, so that the lamp tube can be selectively turned off through an external switch.

Since the power circuits for driving each group of lamp tubes are independent of each other, the multi-output electronic ballast contains multiple AC-DC conversion circuits, and the AC-DC conversion circuit contains multiple high-cost power components. The output electronic ballast not only takes up space due to its large size, but also costs a lot.

Therefore, how to develop a method that can solve the high cost and space occupation of the known multi-output electronic ballast is an urgent problem to be solved at present.

Contents of the invention

A main purpose of the present invention is to provide a multi-output electronic ballast, which has the advantages of low cost, small size and no space occupation, and allows the user to selectively turn off multiple groups (units) of lamp tubes. Purpose.

In order to achieve the above purpose, a more generalized embodiment of the present invention is to provide a multi-output electronic ballast to drive multiple groups of lamps, including: an AC-DC conversion circuit connected to a second external switch and a DC a bus, which converts an AC input voltage through the second external switch into a high-voltage DC voltage; a first inverter circuit, connected to the DC bus, selectively converts the high-voltage DC voltage into a first AC output voltage to a first group of lamp tubes; a second inverter circuit connected to the DC bus to convert the high-voltage DC voltage into a second AC output voltage to a second group of lamp tubes; an auxiliary voltage generating circuit for generating an auxiliary voltage; and a control circuit connected to a first external switch, the auxiliary voltage generating circuit and a first inverter control circuit of the first inverter circuit, the control circuit according to the conduction of the first external switch The state selectively receives the electric energy of the auxiliary voltage to generate a control signal to the first inverter control circuit; wherein, when the control signal generated by the control circuit is transmitted to the first inverter control circuit, the first inverter The inverter control circuit starts to operate so that the first inverter circuit converts the high-voltage DC voltage into the first AC output voltage to the first group of lamp tubes.

The present invention only includes a single AC-DC conversion circuit, and through the control circuit, controls whether one of the inverter circuits is running, which is different from the known multi-output electronic ballast that contains multiple AC-DC conversion circuits, so that AC-DC conversion circuits can be saved. The cost of the power components inside the DC conversion circuit, and the control circuit is simple, so the multi-output electronic ballast of the present invention has the advantages of small size and no space occupation.

Description of drawings

FIG. 1 is a schematic circuit block diagram of a multi-output electronic ballast according to a preferred embodiment of the present invention.

FIG. 2 is a detailed schematic diagram of a control circuit of a multi-output electronic ballast according to a preferred embodiment of the present invention.

FIG. 3 is a detailed circuit diagram of a multi-output electronic ballast according to a preferred embodiment of the present invention.

The reference numerals in the above-mentioned accompanying drawings are explained as follows:

Lamp 1

Multi-output electronic ballast 2

Multiple (groups) lamps 3

Power supply equipment 4

The first end 4a of the power supply device

The second terminal 4b of the power supply device

The first group of lamps 31

The second group of lamps 32

DC bus 20 (DC bus)

AC-DC conversion circuit 21

The first inverter circuit 22

The second inverter circuit 23

Auxiliary voltage generating circuit 24

control circuit 25

EMI filtering unit 211

Rectifier circuit 212

Power Factor Correction Circuit 213

The first inverter control circuit 221

The first switch circuit 222

The second voltage divider circuit 223

First resonant circuit 224

First preheating coil 225

The first protection circuit 226

The second inverter control circuit 231

Second switch circuit 232

The third voltage divider circuit 233

Second resonant circuit 234

Second preheating coil 235

Second protection circuit 236

Detection circuit 251

Power factor correction control circuit 2131

Voltage divider rectifier circuit 2511

The first voltage divider circuit 2512

The detection terminal 25a of the control circuit

The first switching element Q1

The control terminal Q1a of the first switching element

The current input terminal Q1b of the first switching element

Second switching element Q2

The control terminal Q2a of the second switching element

The current input terminal Q2b of the second switching element

The third switching element Q3

The control terminal Q3a of the third switch element

Fourth switching element Q4

Fifth switching element Q5

AC input voltage Vin

AC input current Iin

The first AC output voltage Vo1

The second AC output voltage Vo2

Auxiliary voltage Vcc

High voltage DC voltage Vdc

Switching signal Vs1

First external switch S1

Second external switch S2

Control signal Vc

The first DC voltage Vdc1

Second DC voltage Vdc2

The first capacitor C1

Second capacitor C2

The third capacitor C3

Fourth capacitor C4

The first resistor R1

Second resistor R2

The third resistor R3

Fourth resistor R4

Fifth resistor R5

Sixth resistor R6

Seventh resistor R7

Eighth resistor R8

Ninth resistor R9

first diode D1

second diode D2

third diode D3

Fourth diode D4

The first Zener diode ZD1

Second zener diode ZD2

The first inductance L1

Bus capacitance Cb

The first resonant inductance Lr1

The first resonant capacitor Cr1

Detailed ways

Some typical embodiments embodying the features and advantages of the present invention will be described in detail in the description in the following paragraphs. It should be understood that the present invention is capable of various changes in different ways without departing from the scope of the present invention, and that the description and drawings therein are illustrative in nature rather than limiting the present invention.

Please refer to Fig. 1, which is a circuit block diagram of a multi-output electronic ballast in a preferred embodiment of the present invention. As shown in Fig. 1, a multi-output electronic ballast 2 and a plurality (groups) of lamp tubes 3 are arranged on a lamp 1, wherein the multi-output electronic ballast 2 outputs a plurality of output voltages to respectively drive a plurality (groups) of lamp tubes 3, in this embodiment, the multi-output electronic ballast 2 uses the AC The input voltage Vin is converted into a high-frequency first AC output voltage Vo1 and a second AC output voltage Vo2, and each set of lamp tubes 31 and 32 includes at least one lamp tube, but not limited thereto. The multi-output electronic ballast 2 includes an AC-DC conversion circuit 21, a first inverter circuit 22, a second inverter circuit 23, an auxiliary voltage generating circuit 24 and a control circuit 25, wherein the AC-DC conversion circuit The input side of 21 is connected to the power supply device 4, and the output side of the AC-DC conversion circuit 21 is connected to the DC bus 20 (DC bus), so as to convert the AC input voltage Vin (mains power) into a high-voltage DC voltage Vdc, for example 450V.

The input side of the first inverter circuit 22 is connected to the DC bus 20, and the output side of the first inverter circuit 22 is connected to the first group of lamp tubes 31 for selectively converting the high-voltage DC voltage Vdc into a high-frequency first AC output voltage Vo1. The input side of the second inverter circuit 23 is connected to the DC bus 20, and the output side of the second inverter circuit 23 is connected to the second group of lamp tubes 32 for converting the high-voltage DC voltage Vdc into a high-frequency second AC output voltage Vo2. The auxiliary voltage generating circuit 24 is used to generate an auxiliary voltage Vcc, such as 15V. The control circuit 25 is connected to the DC bus 20, the auxiliary voltage generating circuit 24, and a first inverter control circuit 221 of the first inverter circuit 22, and is connected to the power supply device 4 through an external first external switch S1 to be used according to The state of the first external switch S1 selectively introduces the auxiliary voltage Vcc or the high-voltage DC voltage Vdc into the first inverter control circuit 221 through the control circuit 25 to control whether the first inverter circuit 22 is running, so as to achieve selective shutdown The purpose of the first group of lamp tubes 31 . In this embodiment, the multi-output electronic ballast further includes a bus capacitor Cb connected to the DC bus 20 for filtering the high voltage DC voltage Vdc.

Please refer to Fig. 1 again, in order to allow the user to control whether the two groups of lamp tubes 31, 32 emit light, the first external switch S1 is connected in series to the detection terminal 25a of the control circuit 25, and the input side of the AC-DC conversion circuit 21 is connected in series A second external switch S2 is connected, and the operation of the first inverter circuit 22 and the second inverter circuit 23 is determined by whether the second external switch S2 is turned on or not. When the second external switch S2 is turned on, the AC input voltage Vin is introduced into the input side of the AC-DC conversion circuit 21 through the second external switch S2, and the AC-DC conversion circuit 21 converts the AC input voltage Vin into a high-voltage DC voltage Vdc. The second inverter circuit 23 converts the high voltage DC voltage Vdc into a second AC output voltage Vo2 to drive the second group of lamps 32 to emit light.

One end of the first external switch S1 can be connected to a first end 4a (fire wire) or a second end 4b (ground wire) of the power supply device 4, and the other end of the first external switch S1 is connected to the detection of the control circuit 25 In this embodiment, the first external switch S1 is connected to the second terminal 4b of the power supply device 4 . When the first external switch S1 is turned on, the energy of the AC input voltage Vin will be transmitted to the detection terminal 25a of the control circuit 25, so that the control circuit 25 generates a control signal Vc to the first inverter according to the conduction state of the first external switch S1. The inverter control circuit 221, wherein the electric energy required for the operation of the control signal Vc is selectively provided by the auxiliary voltage Vcc or the high-voltage DC voltage Vdc. At this time, the first inverter control circuit 221 of the first inverter circuit 22 will The first inverter circuit 22 is controlled to start operating, and converts the high-voltage DC voltage Vdc into the first AC voltage Vo1 to make the first group of lamp tubes 31 emit light. Conversely, during daytime, when the outdoor light is sufficient or when no one is working indoors, the user can turn off the first external switch S1, so that the energy of the AC input voltage Vin cannot be transmitted to the detection terminal 25a of the control circuit 25 through the first external switch S1, The control circuit 25 stops generating the control signal Vc to the first inverter control circuit 221 according to the off state of the first external switch S1 to control the first inverter circuit 22 to stop running.

Please refer to Fig. 2 and cooperate with Fig. 1, wherein Fig. 2 is the detailed circuit diagram of the control circuit of the multi-output electronic ballast of the preferred embodiment of the present invention, as shown in Fig. 2, the control circuit 25 comprises a detection circuit 251, a The first switch element Q1 and a first resistor R1, wherein the detection circuit 251 is connected to the control terminal Q1a of the first switch element Q1 and the first external switch S1 for controlling the first switch according to the conduction state of the first external switch S1 The element Q1 is turned on or off, and the first switching element Q1 is connected to the auxiliary voltage generating circuit 24 and connected to the first inverter control circuit 221 through the first resistor R1. In this embodiment, the detection circuit 251 includes a voltage divider rectifier circuit 2511, a first capacitor C1, a first Zener diode ZD1 (Zener Diode), a first voltage divider circuit 2512, a second switch element Q2 and A second resistor R2, wherein the voltage dividing and rectifying circuit 2511 is connected to the first external switch S1, the cathode terminal of the first Zener diode ZD1 is connected to the voltage dividing and rectifying circuit 2511 and one end of the first capacitor C1, and the first Zener diode The anode terminal of ZD1 is connected to the first voltage dividing circuit 2512, and the first voltage dividing circuit 2512 is connected between the first Zener diode ZD1 and the control terminal Q2a of the second switching element Q2, and the current input terminal Q2b of the second switching element Q2 It is connected to the control terminal Q1a of the first switching element Q1 through a second resistor R2.

In this embodiment, the voltage dividing and rectifying circuit 2511 includes a third resistor R3, a fourth resistor R4 and a first diode D1, and the third resistor R3, the fourth resistor R4, the first external switch S1 and the first diode D1 A diode D1 is connected in series to divide and rectify the AC input voltage Vin transmitted from the first external switch S1, and generate a first DC voltage Vdc1 to the first capacitor C1. The voltage value of the first Zener diode ZD1 used to limit the first DC voltage Vdc1 must be greater than, for example, a threshold voltage, such as 10V, before it can be turned on. When the first DC voltage Vdc1 charges the first capacitor C1 When the voltage value of the first direct current voltage Vdc1 is greater than the threshold voltage value, the first Zener diode ZD1 is turned on.

The first voltage divider circuit 2512 includes a fifth resistor R5 and a sixth resistor R6, the fifth resistor R5 is connected between the first Zener diode ZD1 and the control terminal Q2a of the second switching element Q2, and the sixth resistor R6 is connected to The fifth resistor R5 and the control terminal Q2a of the second switching element Q2, when the first Zener diode ZD1 is turned on, the first voltage divider circuit 2512 will pass the fifth resistor R5 and the sixth resistor R6 to the first DC voltage Vdc1 Divide the voltage to generate a second DC voltage Vdc2, the second DC voltage Vdc2 can turn on the second switch element Q2, then the detection circuit 251 will output a switching signal Vs1 of low potential, in this embodiment, due to the switching The signal Vs1 is relatively lower than the high voltage DC voltage Vdc or the auxiliary voltage Vcc, so the first switch element Q1 can be turned on. In this embodiment, the control circuit 25 further includes a seventh resistor R7 for current limiting, which is connected to the current input terminal Q1b of the first switching element Q1 and the DC bus 20. When the first switching element Q1 is turned on, the high voltage The DC voltage Vdc or the auxiliary voltage Vcc passes through the first switch element Q1 to the first inverter control circuit 221 to generate a control signal Vc to the first inverter control circuit 221 to make the first group of lamps 31 emit light.

When the first external switch S1 is turned on and the first switch element Q1 is turned on, the power of the control signal Vc is continuously provided by the auxiliary voltage Vcc, so that the first inverter circuit 22 outputs the first AC output voltage Vo1. The auxiliary voltage generating circuit 24 can use the electric energy of the second AC output voltage Vo2 or the high-voltage DC voltage Vdc to generate the auxiliary voltage Vcc. When the circuit starts to operate and the voltage value of the auxiliary voltage Vcc is insufficient, it cannot provide the first inverter control circuit 221 when it is running. For the required energy, in other embodiments, before and after the stable operation of the first inverter circuit 22, the electric energy of the control signal Vc can be provided by the high-voltage DC voltage Vdc or the auxiliary voltage Vcc respectively. In other words, when the voltage value of the auxiliary voltage Vcc is insufficient, the power of the high voltage DC voltage Vdc is transmitted to the first inverter circuit 221 through the first switching element Q1, that is, the power of the control signal Vc is provided by the high voltage DC voltage Vdc, which is connected to the auxiliary voltage When the voltage of Vcc rises to a sufficient voltage, the power of the auxiliary voltage Vcc is transferred to the first inverter circuit 221 through the first switching element Q1 , that is, the power of the control signal Vc is provided by the auxiliary voltage Vcc instead. In this embodiment, the control circuit 25 further includes a second Zener diode ZD2 and a second capacitor C2, wherein the second Zener diode ZD2 is connected to the current input terminal Q1b of the first switching element Q1 to prevent the control signal from The voltage value of Vc is too high, and the second capacitor C2 is connected to the current input terminal Q1b of the first switch element Q1 to filter and store the energy required by the control signal Vc. When the first external switch S1 is turned on to start the circuit and the voltage value of the auxiliary voltage Vcc is insufficient, the electric energy of the control signal Vc is simultaneously provided by the high-voltage DC voltage Vdc and the second capacitor C2, which can reduce the voltage drop of the control signal Vc After the auxiliary voltage Vcc rises to a sufficient voltage value, the power of the control signal Vc is provided by the auxiliary voltage Vcc. In this embodiment, the control circuit 25 further includes an eighth resistor R8, which is connected between the control terminal Q1a of the first switching element Q1 and the current input terminal Q1b, so as to prevent the malfunction of the first switching element Q1 due to noise interference. .

Please refer to FIG. 3 and cooperate with FIG. 1, wherein FIG. 3 is a detailed circuit schematic diagram of a multi-output electronic ballast in a preferred embodiment of the present invention. As shown in FIG. 3, the AC-DC power conversion circuit 21 includes an electromagnetic interference filtering unit 211 (EMI unit), a rectifier circuit 212 and a power factor correction circuit 213, wherein the electromagnetic interference filter unit 211 is connected to the first external switch S1 and the AC side of the rectifier circuit 212, and the DC side of the rectifier circuit 212 is connected to the power factor correction circuit The input side of the power factor correction circuit 213 is connected, and the output side of the power factor correction circuit 213 is connected to the DC bus 20 .

In this embodiment, the power factor correction circuit 213 includes a power factor correction control circuit 2131, a first inductor L1, a second diode D2, a ninth resistor R9 and a third switch element Q3, wherein the first One end of an inductor L1 is connected to the DC side of the rectifier circuit 212, the other end is connected to the anode end of the second diode D2, and the cathode end of the second diode D2 is connected to the DC bus 20, and the third switch element Q3 is connected to the DC bus 20. The ninth resistor R9 is connected to the first inductor L1 and the second diode D2. The power factor correction control circuit 2131 is connected to the control terminal Q3a of the third switching element Q3, and by controlling the third switching element Q3 to be turned on or off, the current distribution of the AC input current Iin is approximated to the sinusoidal waveform of the AC input voltage Vin, so that The power factor is increased, and the electromagnetic interference filter unit 211 is used to block the high-frequency noise of the multi-output electronic ballast 2 itself and the external noise from the AC input voltage Vin to avoid mutual interference.

In this embodiment, the first inverter circuit 22 includes a first inverter control circuit 221, a first switch circuit 222, a second voltage divider circuit 223 and a first resonant circuit 224, wherein the first inverter control circuit 221 is connected with the control circuit 25 and the first switch circuit 222 for controlling the operation of the first switch circuit 222 . The second voltage dividing circuit 223 is connected to the DC bus 20 for generating a divided voltage (Vdc/2). The first resonant circuit 224 includes a first resonant inductor Lr1 and a first resonant capacitor Cr1 to form a series resonant circuit for making the circuit generate a resonant response. When the first external switch S1 and the second external switch S2 are turned on at the same time, the AC-DC power conversion circuit 21 converts the AC input voltage Vin into a high-voltage DC voltage Vdc, and the control circuit 25 outputs a low-potential control signal Vc to the first The inverter control circuit 221 , at this time, the first inverter control circuit 221 controls the operation of the first switch circuit 222 so that the electric energy of the high voltage DC voltage Vdc is selectively output from the first switch circuit 222 to the first resonant circuit 224 .

In this embodiment, the first switch circuit 222 includes a fourth switch element Q4 and a fifth switch element Q5, the fourth switch element Q4 and the fifth switch element Q5 are connected in series, and the second voltage dividing circuit 223 includes a third capacitor C3 and The fourth capacitor C4, the third capacitor C3 and the fourth capacitor C4 are connected in series. The first inverter circuit 22 converts the high-voltage direct current voltage Vdc into a high-frequency first alternating current by alternately turning on or off the fourth switching element Q4 and the fifth switching element Q5 and the resonance reaction of the first resonant circuit 224. Output voltage Vo1. In this embodiment, the first inverter circuit 22 further includes a first preheating coil 225 (Winding), that is, the first preheating circuit, which has the same magnetic core as the first resonant inductor Lr1 in the first resonant circuit 224. (Core) structure for preheating the first group of lamp tubes 31 .

In addition, the second inverter circuit 23 includes a second inverter control circuit 231, a second switch circuit 232, a third voltage divider circuit 233, a second resonant circuit 234 and a second preheating coil 235, namely the second The second preheating circuit has the same connection relationship and operation mode as the first inverter circuit 22, so it will not be described again. The energy source of the second inverter control circuit 231 is provided by the auxiliary voltage Vcc generated by the auxiliary voltage generating circuit 24, so The second inverter circuit 23 can start running continuously when the second external switch S2 is turned on.

In this embodiment, the first and second inverter circuits 22, 23 further include a first protection circuit 226 and a second protection circuit 236, for when the first or second group of lamp tubes 31, 32 fails, Electronic ballast 2 to protect multiple outputs. The following will take the first group of lamp tubes 31 as an example. The first protection circuit 226 includes a third diode D3 and a fourth diode D4, which are connected to the second voltage divider circuit 223. When the first group of lamp tubes 31 fails, In the positive and negative half periods of the first AC output voltage Vo1, the discharge of the first group of lamp tubes 31 is asymmetrical, for example, only in the positive half period. This unilateral operation will occur without the connection of the first protection circuit 226. One of the voltage values of the third capacitor C3 or the fourth capacitor C4 is too high, for example, higher than the voltage value of the high-voltage DC voltage Vdc, and when, for example, the voltage value of the fourth capacitor C4 is higher than the voltage value of the DC voltage Vdc, The third diode D3 correspondingly connected to the fourth capacitor C4 is turned on, so that the fourth capacitor C4 cannot continue to be charged, so as to prevent the capacitor from being damaged due to an excessively high voltage value of the fourth capacitor C4. Similarly, the connection relationship and operation mode of the internal components of the second protection circuit 236 are similar to those of the first protection circuit 226 , and will not be repeated here.

In summary, the multi-output electronic ballast provided by the present invention only includes a single AC-DC conversion circuit, and controls whether one of the inverter circuits is running through the control circuit, which is different from the known multi-output electronic ballast that includes Multiple AC-DC conversion circuits can save the cost of power components inside the AC-DC conversion circuit. In addition, the control circuit is simple, so the multi-output electronic ballast of the present invention has the advantages of small size and no space occupation. Generally speaking, when the user turns off the first external switch, the control circuit can stop supplying the energy required for the operation of the first inverter control circuit, so that the first inverter circuit stops running, so as to selectively close the first inverter control circuit. Group of light tubes.

The present invention can be modified in various ways by those who are familiar with this technology, but they all do not depart from the scope of protection as claimed in the appended claims.

Claims (14)

1. an electric stabilizer for multi output, organize fluorescent tube to drive more, comprising:

One AC-DC change-over circuit, is connected to one second external switch and a DC bus, and the AC-input voltage via this second external switch is converted to a high-voltage dc voltage;

One first inverter circuit, is connected with this DC bus, optionally this high-voltage dc voltage is converted to one first ac output voltage to, first group of fluorescent tube;

One second inverter circuit, is connected with this DC bus, this high-voltage dc voltage is converted to one second ac output voltage to, second group of fluorescent tube;

One boost voltage produces circuit, in order to produce a boost voltage; And

One control circuit, be connected to one first external switch, one first inverter control circuit that this boost voltage produces circuit and this first inverter circuit, this control circuit optionally receives the electric energy of this boost voltage according to the conducting state of this first external switch and produces one and control signal to this first inverter control circuit;

Wherein, when this control signal that this control circuit produces is sent to this first inverter control circuit, this first inverter control circuit brings into operation and makes this first inverter circuit this high-voltage dc voltage is converted to this first ac output voltage to this first group of fluorescent tube.

2. the electric stabilizer of multi output as claimed in claim 1, wherein this control circuit is more connected to this DC bus, and optionally receives the electric energy of this boost voltage or this high-voltage dc voltage according to the conducting state of this first external switch and produce this and control signal to this first inverter control circuit.

3. the electric stabilizer of multi output as claimed in claim 1, wherein this control circuit comprises:

One first switch element, produces circuit with this boost voltage and is connected;

One first resistance, is connected to this first inverter control circuit and this first switch element; And

One testing circuit, be connected to control end and this first external switch of this first switch element, the conducting state according to this first external switch controls this first switching elements conductive or cut-off.

4. the electric stabilizer of multi output as claimed in claim 3, wherein this testing circuit comprises:

One second resistance, is connected with the control end of this first switch element;

One bleeder rectifier circuit, is connected with this first external switch, to carry out dividing potential drop and rectification to this AC-input voltage and to produce one first direct voltage;

One first electric capacity, is connected with this bleeder rectifier circuit;

One first Zener diode, is connected to this first electric capacity and this bleeder rectifier circuit, is greater than a threshold voltage value with the magnitude of voltage limiting this first direct voltage;

One first bleeder circuit, is connected with this first Zener diode, produces one second direct voltage to carry out dividing potential drop to this first direct voltage; And

One second switch element, the control end of this second switch element is connected with this first bleeder circuit, and the current input terminal of this second switch element is connected with this second resistance.

5. the electric stabilizer of multi output as claimed in claim 4, wherein this bleeder rectifier circuit comprises: one the 3rd resistance, one the 4th resistance and one first diode, and the 3rd resistance, the 4th resistance, this first diode and this first external switch are connected in series.

6. the electric stabilizer of multi output as claimed in claim 4, wherein this first bleeder circuit comprises: one the 5th resistance and one the 6th resistance, 5th resistance is connected between this first Zener diode and control end of this second switch element, and the 6th resistance is connected to the control end of the 5th resistance and this second switch element.

7. the electric stabilizer of multi output as claimed in claim 3, wherein this control circuit more comprises one second Zener diode, is connected to the current input terminal of this first switch element, to prevent the magnitude of voltage of this control signal too high.

8. the electric stabilizer of multi output as claimed in claim 3, wherein this control circuit more comprises one second electric capacity, is connected to the current input terminal of this first switch element, to store the energy needed for this control signal.

9. the electric stabilizer of multi output as claimed in claim 3, wherein this control circuit more comprises one the 7th resistance, is connected to current input terminal and this DC bus of this first switch element.

10. the electric stabilizer of multi output as claimed in claim 3, wherein this control circuit more comprises one the 8th resistance, is connected to control end and the current input terminal of this first switch element, to prevent the first switch element misoperation.

The electric stabilizer of 11. multi output as claimed in claim 1, wherein this first inverter circuit comprises:

One first switching circuit, is connected with this DC bus;

One second bleeder circuit, is connected to this DC bus, to produce a branch pressure voltage;

One first resonant circuit, is connected to this first switching circuit; And

One first inverter control circuit, is connected to this first switching circuit and this control circuit, receives the electric energy of this control signal and controls the operation of this first switching circuit.

The electric stabilizer of 12. multi output as claimed in claim 11, wherein this first inverter circuit more comprises one first protective circuit, is connected with this second bleeder circuit, to prevent the magnitude of voltage of this second bleeder circuit too high.

The electric stabilizer of 13. multi output as claimed in claim 10, wherein this first inverter circuit more comprises one first preheat circuit, to carry out preheating to this first group of fluorescent tube.

The electric stabilizer of 14. multi output as claimed in claim 1, wherein this AC-DC change-over circuit comprises:

One EMI Filtering unit, is connected with this first external switch;

One rectification circuit, is connected with this EMI Filtering unit; And

One circuit of power factor correction, is connected to this rectification circuit and this DC bus, to increase power factor.