CN2302631Y - Stepped starting high-strength gas discharge lamp electronic ballast - Google Patents
Stepped starting high-strength gas discharge lamp electronic ballast Download PDFInfo
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- CN2302631Y CN2302631Y CN 97203172 CN97203172U CN2302631Y CN 2302631 Y CN2302631 Y CN 2302631Y CN 97203172 CN97203172 CN 97203172 CN 97203172 U CN97203172 U CN 97203172U CN 2302631 Y CN2302631 Y CN 2302631Y
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Abstract
The utility model is composed of a commutation filtering circuit, an inverter, a resonance circuit, and an abnormal protection circuit. The abnormal protection circuit comprises an over voltage protection circuit and a starting protection circuit. The resonant circuit is connected to an output circuit of the inverter, the abnormal protection circuit can detect abnormal signals, the output of the abnormal protection circuit can control the input of the inverter, and the resonant circuit is composed of a starting resonator, a working resonator, and a change-over switch. The working resonator is connected in series with the change-over switch, and then the working resonator is connected in parallel with the starting resonator. The change-over switch can be controlled by a starting commutation circuit which acts according to lamp current. The utility model lessens the requirements of the current of a switch tube, and the reliable start of a lamp tube can be realized without the excessive increase of the rated current capacity of the switch tube.
Description
The utility model relates to electronic ballast of high intensity gas discharge lamp, belongs to the illuminating power electronic technology field.
Domestic and international existing electronic ballast of high intensity gas discharge lamp, the half-bridge or the full-bridge high-frequency switch that adopt high-power switch tube to constitute, DC power supply is reverse into the high frequency voltage of 20～50KH, by series parallel resonance loop and fluorescent tube coupling, before starting, lamp do not provide resonance step-up by the shunt-resonant circuit, to start fluorescent tube, fluorescent tube starts the back provides bigger operating current by series resonant tank.
Owing to do not have the assistant starting electrode in the high-pressure sodium lamp, this class high-intensity gas discharge lamp of metal halide lamp, can only lean against its two electrode and add high-tension method and force gas ionization to puncture and start.The high-pressure sodium lamp cold start needs 2～2.5KV, metal halide lamp needs the cold start of 3～4KV ability, and hot starting, hot start voltage will be up to more than the 20KV, high-pressure sodium fluorescent tube pressure is 100～110V during operate as normal, metal halide lamp is 130～140V, and promptly their starting resistor is more than 20 times of normal working voltage.Because high-pressure sodium lamp, metal halide lamp generally all are high-power lamps, operating current is bigger, provide bigger operating current to wish that then the resonant inductance amount is very little, and resonant inductance just need bridge circuit to provide very big starting current could produce resonance high-voltage and start fluorescent tube when measuring very for a short time.Common starting current will reach more than 10 times of steady operation electric current; if high-power switch tube is chosen by the steady operation current capacity; concerning start-up course each time, all be very dangerous then; because the starting current bigger more than 10 times than steady-state current will cause great stress to power electronic device; when particularly sending a telegram here again abnormality appears or runs into instantaneous power-off in fluorescent tube; or fluorescent tube is in when hot; resonance potential can not start fluorescent tube; if the protective circuit time-delay is big, moment just may be burnt high power valve.If select high-power switch tube by more than 10 times of steady-state current capacity, though can relax the contradiction that some start overcurrents, when entering normal operating conditions, electric current will have only 1/10th of rated capacity, cause significantly improving of price and lose the possibility of popularization.
The purpose of this utility model aims to provide a kind of stepped starting type electronic ballast for high strength gas discharge lamp, it can reduce the requirement excessive to the switch tube current in start-up course, increase switching tube rated current capacity that promptly need not be undue just can be realized the reliable startup of fluorescent tube.
The utility model is based on following thinking and realizes:
Inductance in the electric ballast resonant circuit and electric capacity are divided into startup inductance and electric capacity, work inductance and electric capacity two parts, will start inductance and electric capacity and often insert resonant tank; Detect lamp current, in case after fluorescent tube starts, just work inductance and electric capacity are incorporated into resonant tank.Work inductance and electric capacity also can be subdivided into several grades, incorporate resonant tank then step by step into.
The stepped starting type electronic ballast for high strength gas discharge lamp designed according to this thinking; by current rectifying and wave filtering circuit; inverter; resonant circuit; abnormity protection circuit is formed; abnormity protection circuit comprises overvoltage crowbar and starts protective circuit; resonant circuit is connected in the output loop of inverter; abnormity protection circuit detects abnormal signal; the input of its output control inverter; it is characterized in that: described resonant circuit is by starting resonator; the work resonator; diverter switch is formed; work resonator and diverter switch series connection back are in parallel with the startup resonator, and this diverter switch is by a startup commutation circuit control of moving according to lamp current.
Inductance value is big, startup electric capacity is little owing to start, i.e. characteristic impedance of resonant tank and Q value are big, can obtain the reliable startup that higher resonance potential guarantees fluorescent tube like this, can require the current capacity to switching tube to reduce 4～6 times simultaneously.After fluorescent tube started, the startup commutation circuit of moving according to lamp current was just incorporated resonant tank into by will work inductance and electric capacity of diverter switch.Because the characteristic impedance in the resonant tank is because of total inductance reduces, total capacitance increases and reduces, so can provide bigger operating current to fluorescent tube at this moment.Because starting current is close with the steady operation electric current, so need not select for use excessive switching tube just can realize the reliable effect that starts and move.
Applying of electronic ballast of high intensity gas discharge lamp is decided by its reliability and rational price; and reliability depends mainly on start-up course and abnormal condition protection characteristic; only thoroughly solve under rational price after the excessive technical barrier of power electronic device stress in the start-up course, electronic ballast of high intensity gas discharge lamp is promoted the use of just possible.The utility model has solved this problem preferably.
Below in conjunction with embodiment the utility model is elaborated.
Fig. 1 and Fig. 2 are respectively the circuit block diagram and the schematic diagram of the utility model most preferred embodiment;
Fig. 3 is the circuit theory diagrams of the utility model second embodiment.
Electronic ballast of high intensity gas discharge lamp is made up of current rectifying and wave filtering circuit shown in Figure 1, inverter, resonant circuit, abnormity protection circuit; resonant circuit is connected in the output loop of inverter; abnormity protection circuit detects abnormal signal, the input of its output control inverter.Wherein: inverter by noncontacting switch, the main switch of quadrature current instrument transformer and series connection successively, recommend high frequency transformer and constitute the secondary input that connects main switch of quadrature current instrument transformer.Resonant circuit is made up of startup resonator, work resonator, diverter switch, work resonator and diverter switch series connection back are in parallel with the startup resonator, this diverter switch is by a startup commutation circuit control of moving according to lamp current, this startup commutation circuit is by current transformer and be connected on the secondary rectifier of this current transformer, transistor, relay and constitute, the contact of this relay constitutes described diverter switch, the secondary output of current transformer by rectifier rectification after the transistor driving relay.Abnormity protection circuit comprises overvoltage crowbar and starts protective circuit; starting protective circuit is made up of the counter and the restart circuit of the accumulative total number of starts; the input of restart circuit connects the output from described startup resonator; the output of restart circuit connects the control input end of noncontacting switch in the counting end of counter and the described inverter, and the output of counter connects the control input of restart circuit.Overvoltage crowbar is made up of the electric voltage observation circuit of monitoring light tube electric voltage, and the output of electric voltage observation circuit connects the elementary of quadrature current instrument transformer.
Below in conjunction with Fig. 2 the operation principle of electric ballast of the present utility model is described:
In current rectifying and wave filtering circuit: P is that protector, VR are piezo-resistance, and when the serious overvoltage of input voltage, VR blows insurance P by big electric current, thus the protection subsequent conditioning circuit.L01, L02, C0 form anti-jamming circuit, and the high-frequency current of filtering ballast enters electrical network.D1～D4 is a rectifier bridge, and C1, C2, D5～D7 form by the streaming filter circuit, and the angle of flow that makes input current pollutes electrical network greater than 120 degree to improve input power factor and to reduce high order harmonic component as far as possible.C15 is the high-frequency current filter capacitor, and the high direct voltage after the rectification directly is added to the central point of recommending high frequency transformer T2.
Noncontacting switch, quadrature controllable current instrument transformer T1, R14, R19, D11, D12, C11, C12, main switch BG4 and BG7, sustained diode 14 and D15, non-loss buffer C13 and C14, high frequency push-pull transformer T2 constitute self-excitation frequency modulation inverter.T1 detects output current, with driving switch pipe BG4 and BG7, constitutes positive feedback self-oscillation.Wherein D11, D12 are rectifier diode at a slow speed, so that certain dead band to be provided to drive current, avoid main switch BG4 and BG7 conducting simultaneously, make switching tube work in the soft on off state of resonance to reduce turn-off power loss.Quadrature coil to quadrature controllable current instrument transformer T1 feeds direct current, can be equivalent to reduce the electric current coefficient of mutual inductance, force switching tube to turn-off in advance, thereby free-running frequence raises.Noncontacting switch is made up of R15～R18, BG2, BG3, BG5, BG6, when its to R16, when R17 provides direct current, BG2, BG5 are open-minded, the base stage shorted to earth of BG3, BG6, self-excited oscillator can be worked; When withdrawing from the electric current of R16, R17, the self-excited oscillator forced outage.R21, C10, R20, DW4 constitute the start-oscillation circuit of self-excited oscillator, and after the self-excited oscillator starting of oscillation, C10 is by the D13 short circuit, and start-oscillation circuit no longer disturbs self-excited oscillator.For raising the efficiency, reduce the volume weight of high frequency transformer, high frequency transformer is output as the self coupling step-down.Theory analysis is pointed out, for the very big power voltage of fluorescent tube is set in 115V, need 200V square wave excitation resonant tank, half-bridge can only obtain the 140V square-wave voltage, start difficulty when electrical network is under-voltage, and full-bridge circuit is output as the 280V square wave, the reactive power of resonant tank and fly-wheel diode exchange is too big, strengthen the burden of switching tube, increased energy consumption.Employing is recommended the self coupling step-down transformer and then can be obtained best voltage matches effect, and its best no-load voltage ratio is 2 * 280: 200=2.8: 1.
IC is a counter, and restart circuit is made of BG1, SCR1, SCR2.SCR1, SCR2 constitute the bistable state reverse-blocking tetrode thyristor, in order to provide out, to stop signal to the contactless electronic beam switch circuit, when running in the start-up course can not normally start fluorescent tube the time, signal through starting inductance L 1 secondary commutation is added to SCR2 control by DW3, R11 and extremely goes up after R22, C19 time-delay, trigger the SCR2 conducting, force the self-excited oscillator failure of oscillation by contactless electronic beam switch.So the restart circuit that is made of BG1, C5, R5, R7, C6, R8, DW2 enters the time-delay state, the voltage after about 1 minute on the C6 reaches 32V, and SCR1 is triggered, and forces SCR2 to turn-off by C8, and noncontacting switch gets electric, the self-excited oscillator starting of oscillation.IC is binary counter CD4024, when exploration is restarted when reaching 16 times, if lamp still can not start, then the 6th pin of IC becomes high level, forces the BG1 conducting, blocks restart circuit, make circuit enter hibernation-like state, make output can periodically not produce high pressure, to increase fail safe, unless send a telegram here again.
C16, C17, L1 constitute the startup resonator, and L2, C22 constitute the work resonator, and C16, C17 also play the effect of isolating the electrical network high pressure except that constituting the high-frequency resonant network.After self-excited oscillator work, be added on the fluorescent tube Na-Hg after by C16, C17, L1, C25, TR output voltage being boosted by parallel resonance, fluorescent tube is started.After starting, fluorescent tube has that small electric circulation overcurrent instrument transformer T4's is elementary, its secondary BG8 base stage that after rectification, is added to, relay J adhesive after the BG8 conducting, work inductance L 2, the mutual capacitance C22 resonant tank that inserts in parallel, because in parallel work inductance and mutual capacitance in this moment resonant tank, make the characteristic impedance of resonant tank reduce,, make fluorescent tube heat, increase air pressure so can provide bigger operating current to fluorescent tube.After light tube electric voltage rose about 10 minutes, just enter the work of steady operation point.The inductance value that starts inductance is bigger 2～5 times than work inductance, and the capacitance that starts electric capacity is littler 2～10 times than mutual capacitance.
When if fluorescent tube is in sodium consumption dummy status owing to long-term work, light tube electric voltage will rise, to rise through the voltage of rectification by T3 level of light tube electric voltage instrument transformer this moment, make DW6 conducting, BG9 enter conducting state, so the flow through quadrature magnetizing coil of quadrature current instrument transformer T1 of electric current is arranged, force switching tube to turn-off in advance, the natural frequency of vibration rises, the reactance of L1, L2 increases, lamp current will reduce, light tube electric voltage is forced to about 120V, thereby forms the closed loop pressure limiting, so just can not cause the overpower phenomenon.
The fluorescent tube overpower that is caused by the electrical network overvoltage also only is controlled on the power points by this closed loop pressure limiting.
TR is a semistor PTC element, mainly be for adapting on discharge tube around tungsten filament, when fluorescent tube is heated to 300 ℃, utilize Penning effect pipeline start up by preheating fluorescent tube to use, when not being the pipeline start up by preheating fluorescent tube, after time-delay in several seconds, the PTC element is equivalent to open circuit, and resonance potential rises to and can start general fluorescent tube.
For simplifying power supply, the protective circuit on-line operation is in high direct voltage, and the IC circuit is CMOS, only needs very little operating current, and it is powered behind resistance step-down voltage-stabiliser tube with high direct voltage, the shared secondary coil power supply that lays out from T2 of relay and closed loop voltage limiter.
Second embodiment of the present utility model as shown in Figure 3.Its maximum characteristics are to increase cost hardly, do not lower efficiency and realize input power factor is corrected to more than 0.98, and total harmonic current is also compressible below 8%.
This embodiment adopts half-bridge structure, and its inverter is made of quadrature current instrument transformer, noncontacting switch, half-bridge structure main switch, and the output of the secondary and noncontacting switch of quadrature current instrument transformer connects the input of main switch.The sinusoidal adjuster of input current that serial connection is made of L3, C30 in the output loop of current rectifying and wave filtering circuit.The sinusoidal adjuster of input current and oscillator common elements BG7, D14 belong to the simplest circuit topological structure.But because of BG7 flows through the common current of the sinusoidal adjuster of oscillator and input current, its heating is bigger than BG4, so need the radiator structure of increase BG7.
Its operation principle is: when positive half cycle, C30 provides energy for BG4, is coupled to resonant tank and supplies with fluorescent tube.BG7 conducting during negative half period, it also provides the energy storage electric current for L3 except that providing the electric current for oscillator.When BG7 turn-offed, D14 provided the afterflow passage for oscillation circuit and L3, and the hysteresis of oscillator is idle to feed back to C30 to energy by D14, and the magnetic field energy that is stored in simultaneously among the L3 is the C30 charging by D30 simultaneously also.Be to reduce the requirement to rectifier bridge, behind rectifier bridge and 1 microfarad range capacitor C 31 of hf channel is arranged, it can not cause big power current to impact, thereby only needs common rectifier bridge and do not need quick rectifier bridge.D30 realizes the coupling of electrical network and oscillator, and because of the electric current by L3 is discontinuous high frequency triangle wave, D30 needs fast diode to reduce switching loss.D14 also needs the diode of fast recovery characteristics, even adopt the power transistor that damping is arranged, also need incorporate fast diode again into to reduce the switching loss of diode.
So just input current is proofreaied and correct and be the high frequency triangle wave electric current of sinusoidal envelope, pass through the passive correction of C1, L0, C0 again, just can realize and the input voltage homophase, the current waveform of waveform similarity has improved input power factor and has lowered the pollution of harmonic wave to electrical network, particularly can reduce negative phase-sequence higher harmonic current in the center line greatly to three-phase power supply system.
Because of half-bridge circuit power tube emitter common-battery position not, so BG2 adopts optical coupler, to realize signal coupling and potential isolation.
Need realize with a power high frequency transformer T2 step-down rectifier filtering the relay power supply.To the purpose of relay parallel voltage-stabilizing diode DW5 is rapid dissipation and don't over-voltage breakdown triode in order to quicken its magnetic energy, when the electrical network transient state has a power failure, relay can discharge rapidly, so that excision work inductance capacitance when electrical network is sent a telegram here again, prevent to start and cause the instantaneous overcurrent phenomenon owing to fluorescent tube is hot.
The symmetry of C15, C16 is placed except that as the coupling of series parallel resonance loop, can also accomplish can not burn circuit when lamp lead shorted to earth fault, and the function of isolating line voltage is arranged because of C15, C16.
The other parts of circuit and embodiment one are similar.
Consider when running into millisecond when the power failure of hundred Milliseconds is sent a telegram here again, electromagnet inertia and machinery inertial because of relay, impossible abrupt release work resonant circuit, at this moment present low characteristic impedance because of the work resonant circuit, when supposing that dispatch from foreign news agency is sent a telegram here again, if the self-excited oscillator starting of oscillation, then can cause serious overcurrent to impact and burn power switch pipe.Therefore also be connected to the transient state power failure protection circuit that the normally closed contact by relay J constitutes in Fig. 2,3 circuit, this contact is serially connected in the current supply circuit of counter, restart circuit.When fluorescent tube started the back steady operation, the power supply of counter, restart circuit was cut off because of the normally closed contact disconnection of relay.When running into above-mentioned situation, because of the power supply of counter, restart circuit is blocked by this normally closed contact, so can remove the dynamic harzard of circuit.Simultaneously during the fluorescent tube steady operation, the power supply that cuts off counter, restart circuit also can reduce loss.
Principle according to Fig. 1; if select rate of doing work switches such as high-power control power electronic device VDMODFET, IGBT, SIT, MCT for use; with third generation monolithic Active Power Factor Correction, PWMM/ frequency modulation control, integrated ML4830 of protection; in conjunction with the stepped starting circuit, can make high-power electronic ballast of high intensity gas discharge lamp from 1 kilowatt to 100 kilowatts.
Claims (10)
1. stepped starting type electronic ballast for high strength gas discharge lamp; form by current rectifying and wave filtering circuit, inverter, resonant circuit, abnormity protection circuit; abnormity protection circuit comprises overvoltage crowbar and starts protective circuit; resonant circuit is connected in the output loop of inverter; abnormity protection circuit detects abnormal signal; the input of its output control inverter is characterized in that:
Described resonant circuit is made up of startup resonator, work resonator, diverter switch, and work resonator and diverter switch series connection back are in parallel with the startup resonator, and this diverter switch is by a startup commutation circuit control of moving according to lamp current.
2. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 1, it is characterized in that: described startup commutation circuit is by the current transformer that detects lamp current and be connected on the secondary rectifier of this current transformer, transistor, relay and constitute, the contact of this relay constitutes described diverter switch, the secondary output of current transformer by rectifier rectification after the transistor driving relay.
3. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 1 is characterized in that: in described resonant circuit, the inductance value that starts inductance is bigger 2～5 times than work inductance, and the capacitance that starts electric capacity is littler 2～10 times than mutual capacitance.
4. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 1; it is characterized in that: described startup protective circuit is made up of the counter and the restart circuit of the accumulative total number of starts; the input of restart circuit connects the output from described startup resonator; the output of restart circuit connects the control input end of the counting end and the described inverter of counter, and the output of counter connects the control input of restart circuit.
5. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 1, it is characterized in that: described inverter by noncontacting switch, the main switch of quadrature current instrument transformer and series connection successively, recommend high frequency transformer and constitute the secondary input that connects main switch of quadrature current instrument transformer.
6. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 5 is characterized in that: described overvoltage crowbar is made up of the electric voltage observation circuit of monitoring light tube electric voltage, and the output of electric voltage observation circuit connects the elementary of quadrature current instrument transformer.
7. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 5 is characterized in that: described step-down ratio of recommending high frequency transformer is 2.8: 1.
8. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 1 is characterized in that: the sinusoidal adjuster of serial connection input current in the output loop of described current rectifying and wave filtering circuit.
9. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 1, it is characterized in that: described inverter is made of quadrature current instrument transformer, noncontacting switch, half-bridge structure main switch, and the output of the secondary and noncontacting switch of quadrature current instrument transformer connects the input of main switch; The sinusoidal adjuster of serial connection input current in the output loop of described current rectifying and wave filtering circuit, the shared half-bridge main switch down of current sinusoidal adjuster and inverter.
10. stepped starting type electronic ballast for high strength gas discharge lamp as claimed in claim 1; it is characterized in that: described diverter switch comprises Chang Kai and normally closed contact, and its normally closed contact is serially connected in and constitutes the transient state power failure protection circuit in the current supply circuit of restart circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 97203172 CN2302631Y (en) | 1997-04-10 | 1997-04-10 | Stepped starting high-strength gas discharge lamp electronic ballast |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 97203172 CN2302631Y (en) | 1997-04-10 | 1997-04-10 | Stepped starting high-strength gas discharge lamp electronic ballast |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2302631Y true CN2302631Y (en) | 1998-12-30 |
Family
ID=33924112
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 97203172 Expired - Fee Related CN2302631Y (en) | 1997-04-10 | 1997-04-10 | Stepped starting high-strength gas discharge lamp electronic ballast |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2302631Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104716941A (en) * | 2013-12-13 | 2015-06-17 | 上海普锐马电子有限公司 | High-frequency and high-voltage electronic switch with programmable control over conduction time |
| CN105208758A (en) * | 2015-10-15 | 2015-12-30 | 上海笙荣森电子有限公司 | Electronic ballast with overvoltage protection and self-recovery restart functions |
-
1997
- 1997-04-10 CN CN 97203172 patent/CN2302631Y/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104716941A (en) * | 2013-12-13 | 2015-06-17 | 上海普锐马电子有限公司 | High-frequency and high-voltage electronic switch with programmable control over conduction time |
| CN105208758A (en) * | 2015-10-15 | 2015-12-30 | 上海笙荣森电子有限公司 | Electronic ballast with overvoltage protection and self-recovery restart functions |
| CN105208758B (en) * | 2015-10-15 | 2018-12-28 | 上海笙荣森电子有限公司 | A kind of electric ballast for restarting function with overvoltage protection self- recoverage |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |