CN100562204C - Has the electronic ballast that crest factor is proofreaied and correct - Google Patents
Has the electronic ballast that crest factor is proofreaied and correct Download PDFInfo
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- CN100562204C CN100562204C CNB031491111A CN03149111A CN100562204C CN 100562204 C CN100562204 C CN 100562204C CN B031491111 A CNB031491111 A CN B031491111A CN 03149111 A CN03149111 A CN 03149111A CN 100562204 C CN100562204 C CN 100562204C
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Abstract
Because in the known technology, the electronic ballast that has the high power factor of crest factor electric current correction does not cheaply have the function of crest factor electric current correction, cause producing high crest factor and useful life of influencing fluorescent tube.The invention provides one and have the electronic ballast that crest factor is proofreaied and correct cheaply, according to voltage feedback signal, by controlling lamp current simply to reach the function of crest factor electric current correction by the change operation frequency.
Description
Technical field
The invention relates to electric stabilizer, particularly relevant for having the electronic ballast that crest factor is proofreaied and correct.
Background technology
Lamp current crest factor (the Crest Factor of fluorescent lamp (Fluorescent Lamp), C.F.) definition is meant when using electric stabilizer that fluorescent tube is lit a lamp, and lamp current is sealed the ratio that the peak current that produced is tried to achieve divided by current effective value (the root means quare value-RMS value of electric current).But hidden many dithers in the waveform of general alternating current, caused the crest factor of actual state can be higher than 1.414 ideal value.And the numerical values recited of this crest factor had directly and the impact that concerns life-span of fluorescent tube, and this numerical value is advised preferably less than 1.7 by most fluorescent tube manufacturers, and too high numerical value causes the fluorescent tube melanism easily, reduced the useful life of fluorescent tube.
Require to the countries in the world generality electronic ballast have higher power factor (PF) (Power FactorCorrection, PFC), the efficient that produces with the power that improves electronic ballast.But the extra power apparatus that increases can increase the manufacturing degree of difficulty of electronic ballast and improve the cost of electronic ballast, and the burden major part on these costs all can be married again on one's body the user.
Therefore for the engineer of many electronic ballasts, main task is exactly to develop the method with cost-benefit Active PFC.
Power factor correction circuit has two kinds of basic types: a kind of is active power factor correction circuit; Another kind is the passive type power factor correction circuit.
Fig. 1 has shown a kind of traditional active power factor correction circuit, wherein 10 represents bridge rectifier (Bridge Rectifier).This circuit has used booster type topology circuit (Boost Topology) and high frequency to switch an effect electric crystal, can operate in the variable mode of continuous electric inducing current or critical conduction mode (CricalConduction Mode), wherein before beginning one new charge cycle, inductance L 1 allows to release energy to zero.This circuit can satisfy the requirement of harmonic wave fully, therefore can reach high power factor (PF).The power factor correction circuit of this type can reach the power factor (PF) up to 99%.Yet,, cause its material cost (Material Cost) quite high owing to need controller PFC, inductance L 1, high-speed power field to send a telegraph crystal Q1 and fast recovery diode D1.
The passive type power factor correction circuit only uses passive spare part, so its cost is lower than active power factor correction circuit.Fig. 2 has shown simple LC passive type power factor correction circuit.This type circuit operation is at low frequency (50 hertz or 60 hertz), and the low pass or the band pass filter framework (Low Pass or Band Pass Filter Configuration) that have used and used silicon steel plate packing inductance (PFC Choke) L1 and capacitor C 1 to operate as low frequency.Unfortunate, because circuit operation is in low frequency, its lc circuit needs all suitable big of the physical property size of big inductance value and capacitance, especially inductance L 1 and weight, and can produce the buzzer of disturbing the people in use.Therefore, though the passive type power factor correction circuit can reach good performance performance, this type circuit is less at present is used.
Having at present needs many power factor correction circuits cheaply, for example: the power factor correction circuit of the smooth circuit of tool (Valley Fill PFC Circuit).Fig. 3 (A) has shown the power factor correction circuit of the smooth circuit of tool that can reach high power factor (93%-95%).In this circuit, through per half period that the interchange of rectification is imported, filter capacitor C1, C2 charge by diode D2 with the polyphone form, and charge to the interchange peak voltage (suppose that diode is an ideal diode, do not have cross-pressure on the diode) of half.All charged to the interchange peak voltage of half as capacitor C 1, C2 after, only there is voltage in DC line just can provide output current drop to half interchange peak voltage along with sinusoidal waveform below by capacitor C 1, C2.Process at output current, capacitor C 1 and C2 provide load current with the state of parallel connection, until the ac voltage of rectification is higher than the voltage of electric capacity once again when next cycle, it is desirable that (capacitance of supposing electric capacity is very big down, voltage does not have decline behind the capacitor discharge), this value is the interchange peak voltage value of half, and the voltage waveform of direct current output is shown in Fig. 3 (B).Can learn that via simple calculating it is full-time about 37% being lower than peaked half time at the sine-shaped numerical value that changes along with time shaft, this is worth the work frequency of electric capacity (Duty Cycle) value just.Idle (Idle) time of electric capacity remaining 63%, then provide by importing directly through the interchange of rectification.Such framework can significantly increase power quality and power factor (PF).But the shortcoming of the power factor correction circuit maximum of the smooth circuit of tool promptly is that very big ripple voltage (Ripple Voltage) is arranged, and is about half of AC-input voltage.The electronic ballast that any use is such will not cause sizable crest factor value if do not revise lamp current.Major part is used in the semibridge system field effect electric crystal (MOSFET) of electronic ballast of fluorescent lamp though driver or controller cost are low, does not have the function of adjusting lamp current.Under most situation, determined sequential electric capacity (timing capacitor) and resistance after, the frequency of operation of driver has just been decided.The field effect electric crystal drives or uses the electronic ballast of controller cheaply, and its lamp tube current is all unjustified.Therefore when direct current chain (DC bus) when voltage changes, lamp current also can be along with direct voltage ripple (DC ripple) variation.This might make the crest factor value of lamp current cause the useful life that reduces fluorescent tube above 1.7.Therefore, for not having the stable controller of low cost of electric current adjustment capability, and be not suitable for using the power factor correction circuit of the smooth circuit of tool.Fig. 4 (A) has shown a typical electrical minor stabilizer that makes the power factor correction circuit of the smooth circuit of apparatus, wherein 20 represent semibridge system field effect electric crystal driver (Half-BridgeMOSFET Driver), 30 represent fluorescent tube, and Fig. 4 (B) has shown the current waveform of fluorescent tube 30.Owing to do not revise lamp current, the crest factor of its lamp current will be easy to just exceed 1.7.
Summary of the invention
In above-mentioned background of invention, known technology is the electronic ballast of high power factor cheaply, owing to do not have the function of crest factor electric current correction, causes producing high crest factor and useful life of influencing fluorescent tube.The suitable height of cost of electronic ballast of high power factor that perhaps has the function of crest factor electric current correction.
Main purpose of the present invention has provided simply and has had the electronic ballast that crest factor is proofreaied and correct cheaply, makes to have the function that has crest factor to proofread and correct under the High Level DC Voltage ripple, with useful life of prolonging lamp tube effectively.
Another object of the present invention is to utilize electronic type to stabilize controller correcting current crest factor, to reduce the crest factor of lamp current.
For achieving the above object, the invention provides a kind of electronic ballast that crest factor is proofreaied and correct that has, comprise:
One full-wave rectifying circuit becomes a commutating voltage in order to rectification one AC-input voltage;
One transducer converts this commutating voltage to an output AC voltage;
One power factor correction circuit is connected between this full-wave rectifying circuit and this transducer, in order to improve the power factor (PF) of this full-wave rectifying circuit;
One voltage signal generator is connected between this power factor correction circuit and this transducer, so that a voltage signal to be provided;
One controller is connected between this voltage signal generator and this transducer, switches signal to this transducer according to this voltage signal to export one;
One LC oscillating circuit comprises a concussion inductance and a concussion electric capacity, and this oscillating circuit is connected between this transducer and the fluorescent lamp;
Wherein when this commutating voltage raises, this transducer improves a concussion frequency of this output AC voltage according to this switching signal, the electric current that flows through this concussion inductance is suppressed, and when commutating voltage reduces, this transducer reduces this concussion frequency according to this switching signal, and the fall of the electric current that flows through this concussion inductance is reduced.
Described electronic ballast with crest factor correction, wherein above-mentioned full-wave rectifying circuit is to be bridge rectifier.
Described electronic ballast with crest factor correction, wherein above-mentioned transducer is to be the semibridge system AC/DC converter.
Described electronic ballast with crest factor correction, wherein above-mentioned semibridge system AC/DC converter comprises two field effect electric crystals.
Described electronic ballast with crest factor correction, wherein above-mentioned power factor correction circuit is to be a smooth circuit.Refer in particular to this moment and be applicable to a kind of electronic ballast that is used for fluorescent tube with crest factor correction.
Described electronic ballast with crest factor correction, wherein above-mentioned smooth circuit comprises at least two electric capacity and three diodes, when making one of these two electric capacity electric capacity cross-pressure be lower than this commutating voltage, make these two electric capacity carry out a charging process with the series connection form, when one of these two electric capacity electric capacity cross-pressure was higher than this commutating voltage, these two electric capacity carried out a discharge process with parallel form.
Described electronic ballast with crest factor correction, wherein above-mentioned voltage signal generator are to be a series connection resistance circuit.
Described electronic ballast with crest factor correction, wherein above-mentioned controller is by carrying out warm with a resonance frequency that is higher than this LC oscillating circuit.
Described electronic ballast with crest factor correction, wherein above-mentioned controller is by starting this fluorescent lamp with the resonance frequency near this LC oscillating circuit.
Described have an electronic ballast that crest factor is proofreaied and correct, the scope of wherein above-mentioned switching signal for the 50k hertz to the 80K hertz.
In sum, the present invention utilizes voltage feedback signal to adjust the frequency of operation of electronic ballast by controlling lamp current simply by the change operation frequency.Therefore can be by by the stable controller of electronic type simply and cheaply, the function that electronic ballast is had have crest factor to proofread and correct under the High Level DC Voltage ripple is with the crest factor that reduces lamp current effectively and the useful life of prolonging lamp tube.
Description of drawings
Fig. 1 is the circuit diagram of active Active PFC in the known technology;
Fig. 2 is the circuit diagram of passive type Active PFC in the known technology;
Fig. 3 (A) and Fig. 3 (B) are the circuit diagram and the output voltage waveforms thereof of the Active PFC of the smooth circuit of tool in the known technology;
Fig. 4 (A) and Fig. 4 (B) are the electronic ballast schematic diagram and the lamp current waveforms thereof of the power factor correction circuit of the smooth circuit of tool in the known technology;
Fig. 5 is the circuit diagram of the electronic ballast of a preferred embodiment of the present invention;
Fig. 6 is the calcspar with stable controller of electronic type of crest factor correction of the present invention;
Fig. 7 is the lamp current waveform of electronic ballast of the present invention.
Embodiment
Some embodiments of the present invention can be described in detail as follows.Yet except describing in detail, the present invention can also be widely implements at other embodiment, and scope of the present invention do not limited, its with after claim be as the criterion.
Moreover for clearer description being provided and being more readily understood the present invention, graphic interior each several part is not drawn according to its relative size, and some size is compared with other scale dependents and exaggerated; Incoherent detail section is not drawn fully yet, in the hope of graphic succinct.
For electronic ballast, the most cost-efficient topology circuit diagram is semibridge system LC resonant circuit (Half-Bridge L-C Resonant Circuit).Fig. 5 has shown that the present invention makes the preferred embodiment of semibridge system LC resonating electron formula stabilizer of the power factor correction circuit of the smooth circuit of apparatus, wherein 40 represents one to have the stable controller of electronic type that crest factor is proofreaied and correct cheaply.Resistance R 1 provides voltage Vdd positive voltage as controller 40.Resistance R 2, R3 series connection provides the Voltage Feedback signal V of a dividing potential drop as controller 40 in the mode of dividing potential drop at an A
FB, also can provide this voltage feedback signal V with any voltage signal generator
FB, but be minimum with the cost of the formed voltage signal generator of series resistance circuit.The semibridge system DC/AC transducer that the second half section of this circuit then is made up of two high-voltage field effect electric crystals Q1, Q2, by control end points Hi, Lo two high-voltage field effect electric crystal Q1, Q2 are switched in different time points, just DC can be converted to AC power supplies and drive fluorescent tube 30 by controller 40.The stable controller 40 of electronic type with crest factor correction uses minimum part to reach fluorescent tube startup (Lamp Ignition) and lamp current restriction.At this topology circuit, by switching frequency being operated resonance frequency, so that the LC resonant circuit can start fluorescent tube 30 near resonance trough L, C4.After starting, L can be used as the lamp tube current limiting element.The impedance of inductance is proportional to frequency of operation.So, when the voltage of direct current chain raises, the voltage of Voltage Feedback signal VFB also and then improves, when controller 40 is received the signal of direct current chain voltage rising, can improve the switching rate of high-voltage field effect electric crystal Q1, Q2, reach the effect that suppresses electric current by the impedance that can improve inductance by the raising frequency of operation.On the contrary, when the voltage of direct current chain reduces, the voltage of Voltage Feedback signal VFB also and then reduces, when controller 40 is received the signal of direct current chain voltage reduction, can reduce the switching rate of high-voltage field effect electric crystal Q1, Q2, the impedance that can reduce inductance by the reduction frequency of operation slows down the lamp current fall.Therefore, can control lamp current simply by the change operation frequency.
Fig. 6 has shown the simple block diagram of the stable controller of electronic type with crest factor correction.Voltage Vdd is the positive voltage of controller, by the height that can adjust input voltage with reference circuit 50, when voltage Vdd was too high, Zener diode D4 conducting was with deboost, voltage Vdd crosses when hanging down, the misoperation when preventing brownout by low-voltage lock-in circuit 60.Switch signal Hi, Lo for providing by high potential driver 80 and electronegative potential driver 100.By signal Vs, Hi and Lo driving signal as half-bridge field effect electric crystal (as Q1, the Q2 of Fig. 5).Pipeline start up by preheating control 120 is carried out after the preheating in starting fluorescent tube with the frequency of operation near resonance frequency with the resonance frequency that is higher than the LC oscillating circuit.Protection logic controller 130 is the protection logic controller of known technology, closes stabilizer when with the protection stabilizer misoperation being arranged.Voltage control oscillator 110 is accepted Voltage Feedback signal V
FB, to produce concussion frequency input control logic circuit 90.Level shift circuit 70 becomes the current potential of driving voltage in order to the current potential of the controlling signal of conversion and control logical circuit 90.Above-mentioned each functional circuit 50,60,70,80,90,100,110,120 and 130 functional circuits that can use in the known technology.
The present invention is based on the Voltage Feedback V of direct voltage ripple
FBAdjust lamp current, to reach lower crest factor value.When the voltage of direct current chain raise, the voltage of striding on the serial resistance of R2 and R3 raise, so the feedback voltage V of importing via A point
FBAlso can raise, voltage controller oscillator 110 improves frequency of operation at this moment.Therefore the impedance of inductance L also suppresses lamp current thereupon increasing.On the contrary, when the voltage of direct current chain reduced, the voltage of striding on the serial resistance of R2 and R3 reduced, so the feedback voltage V that imports via A point
FBAlso can reduce, this moment, voltage controller oscillator 110 reduction frequency of operation were with the lamp current fall of releiving.Output current wave after adjusting frequency is for as shown in Figure 7, all by cancellation, therefore can effectively reduce the crest factor value in the higher and lower part of electric current.Preferable frequency conversion rate scope of the present invention for the 50k hertz to the 80k hertz.Utilize the method, system can reduce the crest factor value easily makes it less than 1.7.
Compare with known technology, it is that known technology is unexistent that the present invention has many features. Such as Fig. 6 institute The stabilizer system that shows is solution quite cheaply. The lamp of level after in this circuit not being The mode of tube current feedback is controlled lamp current, on the contrary, is the voltage that utilizes the direct-current chain of prime Feedback VFB adjusts lamp current as a control signal. Known current feedback generally needs again Convert the lock signal that returns of lamp current (alternating current) to DC voltage feedback signal, need extra unit Part is obtained the feedback signal of electric current and is changed into voltage signal. Therefore voltage feedback signal is compared to electric current Feedback except cost is low, obtains and uses also easilier. Controller 40 is obtained the feedback of direct-current chain Voltage VFB and Adjustment operation frequency are adjusted lamp current to reduce crest factor. In addition, with Known have the electronic ballast of adjusting the lamp current function different be that the present invention does not need one Loop formula (Close-Loop) control system of individual costliness. Main purpose of the present invention is to reduce lamp The crest factor value of tube current, rather than want the size of current of rigorous control lamp current, so not Need expensive closed loop control system. Because this is that an open loop formula (Open-Loop) is System does not need to go to note unsettled problem as loop.
The supply factory of many traditional semibridge systems field effect electric crystal driver or low-cost stabilizer controller Merchant's suggestion solves this problem in discrete mode. And this solution needs extra part The change of the staged operating frequency that crest factor is proofreaied and correct is provided. But, the system of this discontinuous formula, Its cost is higher, and the performance performance is very not satisfactory yet. On the other hand, system of the present invention is collection Become circuit, and the reliable solution party that feedback provides the LINEAR CONTINUOUS of lamp current to adjust based on voltage Method. Therefore, the invention provides a low cost and more high performance reliable solution.
Claims (10)
1, a kind of electronic ballast with crest factor correction is characterized in that, comprises:
One full-wave rectifying circuit becomes a commutating voltage in order to rectification one AC-input voltage;
One transducer converts this commutating voltage to an output AC voltage;
One power factor correction circuit is connected between this full-wave rectifying circuit and this transducer, in order to improve the power factor (PF) of this full-wave rectifying circuit;
One voltage signal generator is connected between this power factor correction circuit and this transducer, so that a voltage signal to be provided;
One controller is connected between this voltage signal generator and this transducer, switches signal to this transducer according to this voltage signal to export one;
One LC oscillating circuit comprises a concussion inductance and a concussion electric capacity, and this oscillating circuit is connected between this transducer and the fluorescent lamp;
Wherein when this commutating voltage raises, this transducer improves a concussion frequency of this output AC voltage according to this switching signal, the electric current that flows through this concussion inductance is suppressed, and when commutating voltage reduces, this transducer reduces this concussion frequency according to this switching signal, and the fall of the electric current that flows through this concussion inductance is reduced.
2, the electronic ballast with crest factor correction according to claim 1 is characterized in that wherein above-mentioned full-wave rectifying circuit is to be bridge rectifier.
3, the electronic ballast with crest factor correction according to claim 1 is characterized in that wherein above-mentioned transducer is to be the semibridge system AC/DC converter.
4, the electronic ballast with crest factor correction according to claim 3 is characterized in that wherein above-mentioned semibridge system AC/DC converter comprises two field effect electric crystals.
5, the electronic ballast with crest factor correction according to claim 1 is characterized in that wherein above-mentioned power factor correction circuit is to be a smooth circuit.
6, the electronic ballast with crest factor correction according to claim 5, it is characterized in that, wherein above-mentioned smooth circuit comprises at least two electric capacity and three diodes, when making one of these two electric capacity electric capacity cross-pressure be lower than this commutating voltage, make these two electric capacity carry out a charging process with the series connection form, when one of these two electric capacity electric capacity cross-pressure was higher than this commutating voltage, these two electric capacity carried out a discharge process with parallel form.
7, the electronic ballast with crest factor correction according to claim 1 is characterized in that, wherein above-mentioned voltage signal generator is to be a series connection resistance circuit.
8, the electronic ballast with crest factor correction according to claim 1 is characterized in that wherein above-mentioned controller is by carrying out warm with a resonance frequency that is higher than this LC oscillating circuit.
9, the electronic ballast with crest factor correction according to claim 1, wherein above-mentioned controller is by starting this fluorescent lamp with the resonance frequency near this LC oscillating circuit.
10, according to claim 1 have an electronic ballast that crest factor is proofreaied and correct, it is characterized in that, the scope of wherein above-mentioned switching signal for the 50k hertz to the 80K hertz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031491111A CN100562204C (en) | 2003-06-17 | 2003-06-17 | Has the electronic ballast that crest factor is proofreaied and correct |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031491111A CN100562204C (en) | 2003-06-17 | 2003-06-17 | Has the electronic ballast that crest factor is proofreaied and correct |
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| Publication Number | Publication Date |
|---|---|
| CN1568124A CN1568124A (en) | 2005-01-19 |
| CN100562204C true CN100562204C (en) | 2009-11-18 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNB031491111A Expired - Fee Related CN100562204C (en) | 2003-06-17 | 2003-06-17 | Has the electronic ballast that crest factor is proofreaied and correct |
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5085397B2 (en) * | 2008-04-11 | 2012-11-28 | ルネサスエレクトロニクス株式会社 | Power supply device and semiconductor integrated circuit device |
| TWI407670B (en) | 2009-10-21 | 2013-09-01 | Delta Electronics Inc | Buck and buck/boost pfc circuit systems having auxiliary circuits and method thereof |
| CN102044958B (en) * | 2009-10-23 | 2014-01-01 | 台达电子工业股份有限公司 | Voltage reducing and boosting PFC (Power Factor Correction) circuit system with auxiliary circuit and method thereof |
| CN109039036A (en) * | 2018-08-30 | 2018-12-18 | 维沃移动通信有限公司 | A kind of ac filter circuit, charger and mobile terminal |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2132381Y (en) * | 1992-08-21 | 1993-05-05 | 葛少明 | High power electronic ballast with preheating protective function |
| CN2317595Y (en) * | 1997-11-24 | 1999-05-05 | 陈倜 | Electronic ballast controlled by one-chip computer |
| US6034489A (en) * | 1997-12-04 | 2000-03-07 | Matsushita Electric Works R&D Laboratory, Inc. | Electronic ballast circuit |
| US6107753A (en) * | 1998-12-18 | 2000-08-22 | Philips Electronics North America Corporation | Radio frequency electronic ballast with integrated power factor correction stage |
| CN1341342A (en) * | 1999-12-22 | 2002-03-20 | 皇家菲利浦电子有限公司 | Ballast |
| CN2517223Y (en) * | 2001-10-18 | 2002-10-16 | 上海复旦微电子股份有限公司 | Preheating starting and overcurrent protection control device of electric ballast |
-
2003
- 2003-06-17 CN CNB031491111A patent/CN100562204C/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2132381Y (en) * | 1992-08-21 | 1993-05-05 | 葛少明 | High power electronic ballast with preheating protective function |
| CN2317595Y (en) * | 1997-11-24 | 1999-05-05 | 陈倜 | Electronic ballast controlled by one-chip computer |
| US6034489A (en) * | 1997-12-04 | 2000-03-07 | Matsushita Electric Works R&D Laboratory, Inc. | Electronic ballast circuit |
| US6107753A (en) * | 1998-12-18 | 2000-08-22 | Philips Electronics North America Corporation | Radio frequency electronic ballast with integrated power factor correction stage |
| CN1341342A (en) * | 1999-12-22 | 2002-03-20 | 皇家菲利浦电子有限公司 | Ballast |
| CN2517223Y (en) * | 2001-10-18 | 2002-10-16 | 上海复旦微电子股份有限公司 | Preheating starting and overcurrent protection control device of electric ballast |
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| CN1568124A (en) | 2005-01-19 |
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