CN108463022A

CN108463022A - A kind of multi-layer ceramic capacitance constant current driver circuit for LED

Info

Publication number: CN108463022A
Application number: CN201710086365.4A
Authority: CN
Inventors: 周徐达
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-02-17
Filing date: 2017-02-17
Publication date: 2018-08-28
Anticipated expiration: 2037-02-17
Also published as: CN108463022B

Abstract

The present invention relates to LED drive circuits, more particularly to multi-layer ceramic capacitance constant current driver circuit for LED：Including multi-layer ceramic capacitance and iron inductance, between multi-layer ceramic capacitance and the iron inductance series connection LED light group driven and power frequency AC input terminal；Multi-layer ceramic capacitance has Dc bias effect, and capacity under the conditions of maximum allowable Dc bias is not more than the 70% of its nominal capacity, and the both end voltage virtual value in specified max-flow overcurrent is not less than the 50% of rated supply voltage virtual value；The pressure voltage of multi-layer ceramic capacitance is not less than 0.8 times of rated supply voltage peak value；Both end voltage virtual value of the iron inductance in specified max-flow overcurrent is not less than rated supply voltage virtual value 20%.This programme have resistance to thunder ability is strong, have many advantages, such as self-healing ability, using scrap element resources, using scrap lamp ballasts, reduce grid loss, without electromagnetic interference, tolerance mains fluctuations ability is strong, is run convenient for flicker or light modulation.

Description

A kind of multi-layer ceramic capacitance constant current driver circuit for LED

Technical field

The present invention relates to a kind of LED drive circuit, more particularly to a kind of multi-layer ceramic capacitance constant current driver circuit for LED.

Background technology

LED light source long lifespan, light efficiency are high, can dim on a large scale, and LED lighting technology is expected to as a kind of green lighting technique Replace traditional gas-discharge lamp and incandescent lamp, mass energy is saved for society.LED is a kind of device with constant-voltage characteristic, It must all be lacked in the presence of some by driving circuit, however for several driving circuits of the prior art using when mains-supplied Point makes LED light source be affected in the popularization of lighting area, especially in high-power outdoor or industrial and mineral lighting area, LED illumination Occupation rate of market so far less than 20%, various aspects research shows the reliability of service life bottleneck of driving power be restrict its hair The most basic reason of exhibition.

Most common LED electricity drivings circuit mainly has 3 kinds in the prior art：The first is capacitance-resistance driving circuit, its profit The capacitive reactance of electricity container presses current limliting, the LED light string to be connect to provide a metastable electric current mains voltage drop, this The advantages of kind of circuit is at low cost, small, and for disadvantage it is also obvious that dash current is big when starting, constant-current characteristics is bad, power because Number is low, is unable to high-power.Second is linear constant current driving circuit, it limits LED current using current regulator diode class device, Advantage is at low cost, small, however makees current limiting device due to the use of resistance element, and efficiency is low, fever is big, cannot play LED The power savings advantages of light source, it is also difficult to high-power.Third class is hf switching power supply, this kind of circuit control method, topology Structure species are various, and advantage is that efficient, constant-current characteristics is good, however this kind of circuit structure is complicated, parts number up to 30-60, Lightning protection capability is poor, and reliability and service life are bad, only 2-4 years actual life, is used for indoor lighting no problem, but use In high-power outdoor or industrial and mineral illumination, due to severe working environment, user generally reflects that short life, decreasing failure rate are high.

With the rapid development of LED technology, the market penetration rate of LED illumination nearly 50% at present, a large amount of conventional incandescents, Energy-saving lamp is replaced by LED light source, however in high-power outdoor illumination field, LED market acceptances are generally relatively low, traditional gas Charging source still accounts for dominant position, causes the energy saving progress of high-power outdoor illumination field slow, and basic reason is exactly unique is suitble to Great power LED driving the universal reliability of switching power circuit is low, short life, later stage repair rate are high, even if the prior art is to it A large amount of improvement has been made, due to its unmodifiable circuit complexity, durability, reliability do not have essence so far Progress.

Chinese patent CN102088811A discloses a kind of constant current driver circuit for LED based on LCL resonant networks, the circuit Using simple passive reactance device, capacitor element, realize that the constant current of LED light source drives using the resonance effect of capacitor and inductor, The circuit structure is simple, without active switching devices, and it is low not to overcome existing switch power source driving circuit short life, reliability Foot, however the required reactor capacity of the technology is very big, small product size weight is the 5-8 of prior art Switching Power Supply product Times, additionally, due to the requirement of resonance, component required precision is quite high, therefore cost is also very high, does not have practicability, therefore, grinds Hair one kind both having had long lifespan, reliability height, the low feature of failure rate, cost bulking value and lower Novel constant-flow driving power Circuit just seems particularly necessary.

The ingenious bias characteristic that multi-layer ceramic capacitance is utilized of the present invention, switch is realized with simple passive circuit scheme The performance of constant current, wide input voltage, High Power Factor, low harmony wave, small in volume that power circuit could be realized, while The feature for the reliability high life length that the LCL resonance schemes described in Chinese patent CN102088811A have is realized, and Be also equipped with other advantageous effects not available for said program, be expected to be substantially improved the performance of high-power LED illumination technology with The indicator of costs, promoted LED high-power outdoor illumination field promotion rate.

Invention content

In view of above-mentioned technical problem defect, the present invention provides a kind of multi-layer ceramic capacitance constant current driver circuit for LED, the drives Dynamic circuit can effectively overcome the short slab of the prior art, have that constant current effect is good, reliability is high, long lifespan, at low cost, dash current Outstanding advantages small, power factor is high.

Technical solution is used by the present invention solves above-mentioned technical problem：

A kind of multi-layer ceramic capacitance constant current driver circuit for LED, which includes：

One multi-layer ceramic capacitance C1 and iron inductance a L1, the multi-layer ceramic capacitance C1 and the iron inductance L1 It is connected in series between driven LED light group and power frequency AC input terminal；

The multi-layer ceramic capacitance (C1) has Dc bias effect, capacity under the conditions of maximum allowable Dc bias No more than the 70% of its nominal capacity；Both end voltage of the multi-layer ceramic capacitance (C1) in specified max-flow overcurrent is effective 25% of value not less than rated supply voltage virtual value；The pressure voltage of the multi-layer ceramic capacitance (C1) is not less than rated power supply electricity The 20% of voltage crest value；Both end voltage virtual value of the iron inductance (L1) in specified max-flow overcurrent is not less than specified electricity The 20% of source voltage effective value.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein the multi-layer ceramic capacitance C1 is by more A multi-layer ceramic capacitance series, parallel or connection in series-parallel composition.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein the multi-layer ceramic capacitance C1 by Multiple multi-layer ceramic capacitances be connected into it is multigroup, after every group of serial fuse F1, then it is multigroup compose in parallel, the volume of the fuse F1 Determine blowout current and is less than whole group multi-layer ceramic capacitance C1 rated current virtual values.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein the iron core of the iron inductance L1 Equipped with Unequal distance air gap, the impedance value in rated maximum current is 40-the 100% of its initial impedance value.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein the iron inductance L1 includes gas Body discharging lamp impedance type Inductive ballast.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein the driven LED light group with Rectifier bridge D1 is connected between power frequency AC input terminal, the exchange side of the rectifier bridge D1 is gone here and there with the multi-layer ceramic capacitance C1 Connection is followed by power frequency AC input terminal, and the DC side of the rectifier bridge D1 is connect with the LED light group driven, the iron core electricity Sense L1 connects with the exchange side of the rectifier bridge D1 or DC side.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein the DC side of the rectifier bridge D1 It is parallel with filter condenser C2 and discharge resistance R2.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein the driven LED light group with Industrial Frequency Transformer T is connected between power frequency AC input terminal.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein the driven LED light group with Decompression capacitor C3 is serially connected between power frequency AC input terminal.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein further include that there are one overvoltage to protect It is in parallel with the multi-layer ceramic capacitance C1 to protect device R1, the overvoltage protection device R1；One temperature switch or thermal protector S, The temperature switch or thermal protector S are contacted with the overvoltage protection device R1 appearances, and with power frequency AC input terminal Series connection.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein further include that there are one over current protections Device F is protected, the overcurrent protective device F connects with power frequency AC input terminal.

Preferably, above-mentioned multi-layer ceramic capacitance constant current driver circuit for LED, wherein further include that there are one overvoltage to protect Device (R3) is protected, the overvoltage protection device (R3) is parallel to power frequency AC input terminal after connecting with a fuse (F2), Or it is parallel between power frequency AC input terminal and earthing of casing end.

Above-mentioned technical proposal has the following advantages that or advantageous effect：

1, of low cost：It ingenious the shortcomings that multi-layer ceramic capacitance bias characteristic is utilized of the invention, turns harm into good, passes through letter This disadvantage is changed to the automatic control circuit of energy automatic constant current by single scheme, is realized with extremely simple passive circuit The electric current of LED accurately controls function, avoid chip, transistor etc. active devices use, complete machine component number can drop To 10 or so, in addition its inductance element volume very little, therefore cost is only a few minutes of prior art Switching Power Supply constant current scheme One of.

2, reliability is high：Entire circuit is made of passive devices such as inductance, capacitances completely, and core passive device only has Series loop, avoid using chip, transistor etc. Active controls device, also avoid LCL resonance scheme T-type resonant tank because Component parameters variation is possible to cross resonance overstress, can effectively promote product stability, high temperature, humidity, overvoltage, power grid resonance Etc. adverse circumstances adaptability also greatly improve, expose to the sun and rain outdoors, under the adverse circumstances of lightning impulse, it is inherent Sturdy and durable characteristic can bring high reliability and long-life durable, experiments have shown that its decreasing failure rate is up to 0.5/1000th Hereinafter, less than 1/10th of prior art Switching Power Supply, further increased than LCL resonance scheme reliabilities.

3, small, light-weight：The ceramic condenser that the present invention uses has very big power density, power density It is more times of the 20-300 of general thin capacitor；The maximum iron inductance of the present invention wherein volume, rated current also with input Or output current is suitable, voltage is only slightly larger than supply voltage 20%, therefore volume very little, machine volume weight of the present invention It is slightly less than in same power fluorescent lamp ballast, it is suitable with the LED drive power of existing mainstream technology, and LCL resonance schemes need Two inductors, the capacity of one of inductor have been more than just 2 times of iron inductance capacity of the present invention, machine volume weight It is 5-8 times of the present invention, also very high to the required precision of element, cost is 6 times or more of the present invention, in view of the small of LED illumination Type, cost effective developing direction, hardly have practical value.

4, resistance to thunder ability is strong：Since the Lightning Incoming Wave of passive device, high current stress tolerance are far above active half Conductor device, Lightning performance of the invention are far above prior art Switching Power Supply, coordinate the special connection of iron inductance, experiment card The bright present invention can reach the integrated lightning protection performance of tens times of the prior art, and the year Cumulative Failure Rate that multi-thunder area uses can be less than thousand / mono-.

5, has fault self-recovery ability：The essence of the present invention is the capacitance for using automatic transforming impedance, the simple string of inductance Connection circuit directly controls alternating current and carrys out constant LED current, under the conditions of least favorable, if encountering ceramic condenser breakdown or electricity The problems such as anti-device internal short-circuit, filter capacitor are withered as long as Resistor-Capacitor Unit parameter type selecting is reasonable, be also only for LED light group Series impedance element Parameters variation, the current handling capability decline of electric current are controlled, however can still maintain luminous lighting, only Brightness or stroboscopic index decline, and lamp group remains to luminous lighting, as long as and damaging one in tens elements of prior art Switching Power Supply A, entire lamp often extinguishes failure immediately；For LCL resonance schemes, due to the complexity of T-type resonant network, once element is short Road punctures or the small size variation of parameter, and will break meeting condition of resonance makes LED light group overcurrent burn, it is seen that the present invention has existing Core element failure " self-healing " ability that technology does not have, to bring extremely low crash rate, highway, airport harbour, The high tower illumination occasion of the maintenance difficults such as mine railway will greatly reduce maintenance and repair cost using the present invention.If this The ceramic condenser C1 of invention uses multigroup ceramic condenser connection in series-parallel, or by fuse connection in series-parallel, then some ceramic condenser punctures Or open circuit, it is only the micro variation for causing entire electric power outputting current, performance indicator is almost unchanged, realizes more prominent Self-healing ability, it can be ensured that the entirely ineffective rate in its practical application reaches ten thousand/several hereinafter, very less than the prior art One of.

6, with spontaneous temperature compensation function：The two class ceramic condensers that the present invention uses all have apparent temperature system Number, i.e., capacity is reduced after temperature increases, in this way, when lamp temperatures are higher, ceramic condenser is reduced by thermal capacity, and capacitive reactance increases Greatly, so that output current is reduced, play spontaneous temperature compensation function, for two class ceramic condensers of most of specification, in pole 90% when capacity when limiting temperature is about 20 degree, in this way when lamp temperatures are higher, the output current of power supply can reduce automatically A few percent had not only extended the service life of LED element, but also did not influenced to illuminate, since the effect temperature compensation is by the object of ceramic condenser The spontaneous generation of rationality matter is not necessarily to additional control element, therefore cost increase is zero, and the prior art has temperature compensation function Product, price are generally more high.

7, available to scrap element resources：Ceramic condenser is usually scrapped because bias characteristic test is not up to standard, and this hair Bright to be exactly this disadvantage using ceramic condenser and make a silk purse out of a sow's ear, capacity, which reduces, for the present invention, under maximum voltage is more than The bad ceramic condenser of initial value 70% is exactly the key that the present invention reaches technical purpose, and the present invention is a large amount of former by re-using The waste ceramic capacitance of the unqualified sale that can not dispatch from the factory of Ben Yin bias indexs, not only enables the production cost of itself further decrease, Largely discarded component resource is also used, especially makes the rare metal resources in waste ceramic capacitance that will not waste repetition profit With.

8, it can be recycled and scrap light source electric appliance：In recent years as the LED energy-savings of a large amount of fluorescent lamps are transformed, a large amount of inductance Ballast is discarded, and Inductive ballast performance itself is stable, the service life is extremely long, its parameter of iron inductance of the invention and inductance town It flows device to approach, can directly utilize the Inductive ballast of gas-discharge lamp, in this way, a large amount of Inductive ballasts discarded originally can weigh It is multiple to utilize, it not only saves the nonferrous metal resources such as a large amount of iron copper, LED reducing energy consumptions, the regeneration of waste and old light source electric appliance can also be constituted The green circulatory ecology utilized, has further played the environmental benefit of the present invention, has been cost of the present invention additionally, due to iron inductance Middle accounting the best part, due to reclaiming component, cost of the invention can be used to be expected to be reduced to considerable journey Degree, and the inductance element of prior art, it is far from each other with frequency, the induction reactance parameter of Inductive ballast, it cannot utilize completely.

9, extra long life：Passive device of the present invention, self deterioration speed is extremely slow, performance degradation unobvious, adds It is upper simple in structure, the extremely long service life is can reach, even if being filtered using electrolytic capacitor, since electrolytic capacitor of the present invention is used only for changing Kind stroboscopic can continue luminous lighting if operation LED as usual withered failure circuit, have obvious hundreds thousand of The extra long life of hour is 5-10 times of prior art Switching Power Supply, and its long-life is completely by its intuitive, simple rigid Circuit structure realize, have higher client's degree of recognition.

10, grid loss is reduced：The ceramic condenser element of the present invention is while current control, since it accounts for power supply electricity The terminal voltage of 25% or more pressure deducts the part that iron-core inductance compensation is offset, moreover it is possible to a certain proportion of lagging reactive power is generated, Lagging reactive power is provided from power grid is issued, accounts for about the 5-20% of lamps and lanterns active power, certain idle work(can be realized to power grid Rate compensates, and to reduce grid line loss, stablize network voltage, generates indirect energy saving benefit, the prior art either Switching Power Supply Or linear power supply or LCL resonance schemes, are resistive loads, cannot provide reactive power compensation.

11, low harmony wave, without electromagnetic interference：The Switching Power Supply class driving power of the prior art, electromagnetic interference is more serious, even if Good EMI filter circuit is used, still has a small amount of electromagnetic interference to leak, for the special lightings such as military affairs, scientific research, medical treatment field It closes, electromagnetic interference easy tos produce larger impact, and the present invention is a simple impedance circuit, power frequency state is worked in, in addition iron core Inductance accounts for the terminal voltage of 20% or more supply voltage, and huge induction reactance can make entire power supply to the inhibiting effect of higher hamonic wave Ac-side current be stable power frequency sine wave, will not generate any interference to sensitive equipment without EMI filter circuit, and And enable higher harmonic content extremely low, to have very high power factor.

12, simple production process environmental protection：The present invention is without active control circuit, and the normal parameter error of component will not be led The huge deviation of output current is caused, therefore design is simple, produces simple, test simply, the design cycle of Switching Power Supply is then complicated Much, uncertain factor is also very much, and as LCL resonance schemes, then very high to components accuracy requirement, component parameters error is slightly larger, Condition of resonance is just more big changes, and output current is just more big changes, the deuce to pay for causing design to produce.Because passive The robustness of device, circuit are not necessarily to consider that sealed heat-dissipating, common iron-clad simplify production technology without encapsulating, shell, Decrease the moisture-proof caused chemical solvent exhaust emission of the essential encapsulating of the prior art.

13, tolerance mains fluctuations ability is strong：The insulation performance of ceramic condenser can bear twice specified the short time Voltage will not puncture, (the certainly present invention puncture lamps and lanterns can luminous lighting), as long as of the invention improve ceramic condenser slightly Pressure voltage, you can bearing the voltage of abnormal power supply of 300V or more will not damage, and prior art Switching Power Supply supply voltage is super Cross 265V and may result in damage, China's street lamp power supply, road lamp power supply quality of voltage is not generally high, late into the night voltage be more than 270V frequent occurrence, cause LED street lamp frequent breakage, and the present invention by the outstanding pressure-resistant performance of ceramic condenser can bear be more than 300V supply voltage not Damage.For LCL resonance constant current schemes, if you need to be resistant to the high voltage of 300V, then the volume of two resonant inductances will also increase 20% or so, volume weight cost is almost unimaginable.

14, non-impact current, sparkling operation：Extremely simple impedance current limliting principle, in addition the current limliting of iron core reactor Effect so that its inrush current is ten parts of prior art Switching Power Supply less than 2 times of rated current, therefore collects Middle startup is hardly damaged control contactor, network voltage will not be caused to be recessed, also can directly flicker intermittent duty, is used for signal The occasions such as lamp, obstruction light replace incandescent lamp to obtain obvious energy saving effect.

15, extremely cheap tunable optical driving power is provided：LED is suitble to dim, however the switch based on the prior art Power supply has at high price, the complex circuit of dimming function, failure rate higher, and when dimming scope is big usually flickers, and The impedance constant current principle of the present invention, is allowed to the external dimmer ability for having born, as long as outside is by series impedance, capacitance or changes Become input voltage, can easily change brightness, enables the semiconductor control circuit of job insecurity since it is free of, in principle not It may cause to flicker.

16, scrap products recovery value is big, environmental pressure is small：It is not difficult to find out from circuit structure, 70% or more the present invention's Weight concentrates on iron inductance, and in addition to this account for most of total amount is exactly ceramic condenser, iron inductance in ceramic condenser 90% or more substance is recyclable, nonhazardous the metal simple-substances such as iron, copper, aluminium, nickel, other number of electronic components are seldom, because It is big that this scraps rear recovery value, even if properly recycling, will not cause environment larger harm, and the switch of the prior art is electric Source, not only short life, is equal to electronic waste after scrapping, and recovery value is low, it is likely that the environment caused by not being recycled properly Pollution.

17, new technical solution is provided for LED constant current control technology field：In LED drive power field, so far Only two kinds of generally acknowledged current constant control technology：Utilize the line for switching chop control or utilizing analog electronics technique of power electronic technique Property control program, the essence of two schemes be all the electric current of LED is controlled by controlled transistor, and the present invention using pottery The physicochemical property of porcelain capacitance piezoelectricity bias, forms spontaneous constant current effect, is substantially a kind of object using specific function material Rationality matter realize automatic current control new departure, it neither power electronic technique chop control, nor simulation electronic The Linear Control of technology less relies on the resonant process of conventional passive element, it is seen that it is that one kind being totally different from the prior art Novel control program, provide a kind of distinguished brand new technical scheme for LED control technology fields.

Description of the drawings

Upon reading the detailed description of non-limiting embodiments with reference to the following drawings, the present invention and its feature, outer Shape and advantage will become more apparent.Identical label indicates identical part in whole attached drawings.Not can according to than Example draws attached drawing, it is preferred that emphasis is shows the purport of the present invention.

Fig. 1 is the circuit diagram of multi-layer ceramic capacitance constant current driver circuit for LED in the embodiment of the present invention one；

Fig. 2 is multi-layer ceramic capacitance constant current driver circuit for LED multi-layer ceramic capacitance C-V characteristic schematic diagram of the present invention；

Fig. 3 is multi-layer ceramic capacitance constant current driver circuit for LED multi-layer ceramic capacitance bias characteristic schematic diagram of the present invention；

Fig. 4 is the circuit diagram of multi-layer ceramic capacitance constant current driver circuit for LED in the embodiment of the present invention two；

Fig. 5 is the circuit diagram of multi-layer ceramic capacitance constant current driver circuit for LED in the embodiment of the present invention three；

Fig. 6 is the circuit diagram of multi-layer ceramic capacitance constant current driver circuit for LED in the embodiment of the present invention four；

Fig. 7 is the circuit diagram of multi-layer ceramic capacitance constant current driver circuit for LED in the embodiment of the present invention five.

Fig. 8 is the circuit diagram of multi-layer ceramic capacitance constant current driver circuit for LED in the embodiment of the present invention six.

Specific implementation mode

The present invention is further illustrated with specific embodiment below in conjunction with the accompanying drawings, but not as the limit of the present invention It is fixed.

Referring to Fig. 1, this be first embodiment of the invention circuit diagram, this is the most basic one embodiment of the present invention, Seem very simple on this circuit structure, an exactly multi-layer ceramic capacitance and iron inductance be connected on AC power with Between LED light group, however in fact, this simple circuit makes it creatively obtain by the ingenious combination of component, type selecting It obtained a series of complex active control circuit and is all difficult to the advantageous effect reached.

The operation principle of this circuit is similar to prior art LED capacitance-resistance driving circuits, is being exchanged by capacitor Capacitive reactance in circuit hinders alternating current, to keep the electric current being added in LED element basicly stable in mains voltage variations, However since traditional capacitance-resistance actuation techniques use general thin capacitor, capacitive reactance to immobilize, therefore when AC power electricity Be only capable of control when buckling and flow through the curent change amplitude of LED, can not complete constant current, such as when supply voltage is higher When 10%, for the output current of prior art capacitance-resistance power supply by bigger than normal 12-25%, this will influence the service life of LED element, due to resistance Each element voltage electric current relations of distribution for holding power supply obey impedance triangle relationship, and current fluctuation is excessive in order to prevent, is only capable of subtracting The side pressure of small LED light group, this power factor for allowing for entire lamps and lanterns are greatly lowered, and cause the capacitance-resistance power of the prior art Factor is difficult not adapt to existing technical standard more than 0.5.Therefore the capacitance-resistance driving circuit of the prior art is difficult to high-power Change, because high-power driving power supply has higher requirement to power factor, constant current performance.It is known that multi-layer ceramic capacitance (MLCC capacitances) has the advantages that small, reliable operation, however for using two class ceramic condensers of ferroelectric piezoelectric body medium, Its disadvantage is it is also obvious that be exactly that capacity is unstable, due to the specific physical property of piezoelectric ceramics body, the capacity of multi-layer ceramic capacitance Large change can be generated because of the variation of temperature, Dc bias, frequency, fiber crops are brought using design to many electrical equipments It is tired, such as its capacity reduces rapidly with the raising for applying DC voltage, as shown in Fig. 2, however the present invention be utilized instead it is more This disadvantage of layer ceramic condenser, many experiments show that multi-layer ceramic capacitance also has apparent bias effect under work frequency It answers, i.e., capacity is reduced rapidly as operating voltage improves, and the C-V characteristic of the typical multi-layer ceramic capacitance of test shows (such as Fig. 3 It is shown), capacitive reactance is increased rapidly with alive raising is applied, so that after applying voltage more than certain amplitude, voltage is substantially Electric current rises unobvious after rising, produces spontaneous constant current effect.

In the present invention, the selection requirement of multi-layer ceramic capacitance C1 Dc bias effects is, in nominal DC operating voltage When capacity be not more than the 70% of its rated capacity, experiments have shown that can have obvious constant current effect in this way, if bias is imitated Should be weaker, then constant current effect is poor；Since bias effect is notable under multi-layer ceramic capacitance power frequency, nonlinear characteristic is strong, directly logical It crosses nominal capacity and determines that the current parameters of complete machine are highly difficult, generally can rise situation according to its maximum allowable ripple current and temperature, A safe clearance is stayed, as its specified max-flow over current value, then determines its both end voltage model under the maximum current It encloses, is at least not less than the 25% of rated supply voltage virtual value at this time, so that it may certain constant current effect is generated, if further subtracted Low capacity makes terminal voltage improve, then constant current is better, if having connected decompression capacitor on circuit again as embodiment three C3 is divided, and the terminal voltage of this 25% accounting can also have apparent constant current effect；If the ceramic condenser bias effect selected It answers unobvious and also without decompression capacitor, then the terminal voltage under maximum current will also tune up；If wanted to constant current accuracy It asks high or mains fluctuations is larger, then the terminal voltage under maximum current will also tune up, and experiment shows generally to be adjusted to 80% or more Afterwards, output current amplification when supply voltage increases 20% can control below 10%.Generally by simply testing and hindering The voltage distribution of anti-triangle calculates the specification type that just can determine that and select capacitance, in addition it is also noted that the pressure resistance of ceramic condenser C1 Value can not be less than the 20% of rated supply voltage peak value, because of the reverse voltage compensating action of iron inductance, even if series connection decompression Capacitor, the terminal voltage of ceramic condenser C1 also can be more than the level of half supply voltage, it is contemplated that the insulation surplus of ceramic condenser Larger, pressure voltage can not also be less than 0.2 times of rated supply voltage peak value, to prevent from puncturing.The ceramic condenser C1 of the present embodiment It is made of multiple multi-layer ceramic capacitance connection in series-parallel, and respectively parallel discharge resistance, as long as the specifications parameter of each capacitance meets string The parameters such as total pressure resistance, capacity after parallel connection meet the requirements.It is resistance to force down since the universal capacity of ceramic condenser is small, it needs multiple Connection in series-parallel can be only achieved the capacity and pressure voltage of needs, and the present embodiment uses multiple ceramic condensers, first connects again in parallel, appoints in this way One capacitance breakdown of meaning, the volume change of whole group capacitance are little, it is ensured that entire supply unit continues to run with, and performance indicator does not have yet How many variation, plays the role of good fault self-recovery.

It should be noted that for multi-layer ceramic capacitance is with respect to thin-film capacitor, general equivalent series resistance is larger, especially exists Industrial frequency AC application scenario has certain calorific value, therefore in terms of board design, with due regard to heat dissipation problem, example It is first-class such as to increase copper thickness and area, back of circuit board patch cooling fin or metal shell inner wall at welding circuit board ceramic condenser Deng, make the operating temperature of ceramic condenser less than permission maximum temperature, and pay attention to the adhesive of circuit board and cage connection, It needs thermal conductivity preferably and has the glue ability of certain elasticity, avoid external impacts from damaging ceramic condenser, be also avoided that ceramic condenser Noise amplification generates sense of discomfort.The other embodiment of the present invention is also same.

However it is far from enough only to carry out constant current using only multi-layer ceramic capacitance, (prior art also has using such capacitance current-limiting ), because the constant current performance of ceramic condenser itself is not good enough, far from the constant current accuracy performance requirement for reaching LED power, secondly The higher hamonic wave and power factor problem of circuit can not meet the requirement of high-power illumination, and being finally multi-layer ceramic capacitance has Apparent audible noise, people are generally impatient at the illuminator for sending out noise, and the present invention is in the ceramic condenser thus On the one hand the frequency inductance L1 that connected again in circuit inhibits higher hamonic wave using the smooth function of current of the inductance, on the one hand Also the advanced reactive component for correcting ceramic condenser generation, to improve power factor and make the harmonic wave and power factor of power supply Index is up to standard；In addition constant current row energy can be further promoted, when ceramic condenser is in constant current area by the saturation of iron inductance Between when, capacitive reactance with electric current increase and increase, if at this time the induction reactance of inductance L1 with electric current increase and reduce, unit can be increased The change rate of entire impedance loop under current increment, to promote constant current accuracy.The iron inductance of the present embodiment is using uneven Iron core air gap, a part of iron core air-gap-free or intersection are inserted, and can be comparatively fast saturated, and constant current, a part of iron core is assisted to have air gap, can be in volume Determine to maintain linear condition under maximum current, play the role of smooth electric current, hoisting power factor, certain inductance also can whole lines Property, but constant current effect can be also promoted, because the voltage that it is compensated makes ceramic condenser both end voltage increase, to enable ceramic condenser work Make in more vertical VA characteristic curve section.Experiment shows that impedance value of the inductor in rated maximum current is that it is initial 40-the 100% of impedance value can have preferable constant current effect；Terminal voltages of the iron inductance L1 in rated maximum current be not low In the 20% of rated supply voltage virtual value, preferably in 40% or more supply voltage, too small then filter effect is poor, and harmonic wave index is not It can be up to standard.This iron inductance also makes the current waveform for flowing through ceramic condenser C1 tend to be round and smooth, can reduce ceramic electrical in this way The audible noise of appearance and the low-frequency vibration of generation, prevent noise from having a negative impact.The a small amount of LED capacitance-resistances driving electricity of the prior art Source also uses ceramic condenser, but due to failing to find the physical property that ceramic condenser is special, unreasonable matching and circuit structure It is allowed to almost without constant current effect, the indexs such as harmonic wave, power factor, noise, cost are also bad, therefore only cheap in small-power It is applied in LED bulb field, it is difficult to high-power.

The driving power of the present embodiment design, when LED light group voltage reaches 220V, ± 20% range of mains fluctuations Interior current fluctuation can be not more than 6%, and power factor is up to 0.9 or more at this time, be provided simultaneously with good constant-current characteristics with compared with High power factor.

The advantageous effect of the present embodiment is：

1, of low cost：It ingenious the shortcomings that multi-layer ceramic capacitance bias characteristic is utilized, turns harm into good, passes through simple side This disadvantage is changed to the automatic control circuit of energy automatic constant current by case, and the electricity of LED is realized with extremely simple passive circuit Stream accurately controls function, avoid chip, transistor etc. active devices use, complete machine component number is few, and cost is only It is the part of prior art Switching Power Supply constant current scheme.

2, reliability is high：Entire circuit is completely in series by passive devices such as inductance, capacitances, without complicated T-type Resonance Neural Network Network can effectively promote product stability, and the adverse circumstances adaptability such as high temperature, humidity also greatly improves, expose to the sun and rain outdoors, Under the adverse circumstances of lightning impulse, inherent sturdy and durable characteristic can bring high reliability and long-life durable.

3, resistance to thunder ability is strong：Since the Lightning Incoming Wave of passive device, high current stress tolerance are far above active half Conductor device, Lightning performance of the invention be far above prior art Switching Power Supply, multi-thunder area use year Cumulative Failure Rate can Less than one thousandth.

4, has self-healing ability：Ceramic condenser breakdown or reactor internal short-circuit, filtering are such as encountered under the conditions of least favorable The problems such as capacitance dries up can still maintain luminous lighting as long as Resistor-Capacitor Unit parameter type selecting is reasonable, and only brightness or stroboscopic refer to Mark declines, it can be ensured that and the entirely ineffective rate in its practical application reaches ten thousand/several level.

5, with spontaneous temperature compensation function：Two class ceramic condensers all have apparent temperature coefficient, work as lamp temperatures When higher, the output current of power supply can reduce a few percent automatically, not only extend the service life of LED element, but also not influence to illuminate, nothing It is zero to need additional control element, cost increase.

6, available to scrap element resources：By re-using a large amount of sale that can not dispatch from the factory because bias index is unqualified originally Waste ceramic capacitance, enable the production cost of itself further decrease, also use largely discarded component resources, especially make Rare metal resources in waste ceramic capacitance will not waste recycling.

7, extra long life：Passive device used by the present embodiment, self deterioration speed is extremely slow, performance degradation unobvious, In addition it is simple in structure, the extremely long service life is can reach, there is obvious hundreds thousand of hours extra long lifes.

8, grid loss is reduced：The ceramic condenser element of the present embodiment can generate certain proportion while current control Lagging reactive power, issue certainly power grid provide lagging reactive power, account for about the 5-20% of lamps and lanterns active power, can to power grid reality Now certain reactive power compensation generates indirect energy saving benefit to reduce grid line loss, stablize network voltage.

9, low harmony wave, without electromagnetic interference：The present embodiment is a simple impedance circuit, can make the exchange side of entire power supply Electric current is stable power frequency sine wave, will not generate any interference to sensitive equipment without EMI filter circuit, and enable high order Harmonic content is extremely low, to have 0.9 or more High Power Factor.

10, simple production process environmental protection：The present embodiment will not amplify electricity without active control circuit, element normal parameter deviation Stream error, production mounting technology is simple, test is simple, simplifies production technology, decreases the essential filling of the prior art Chemical solvent exhaust emission caused by glue is moisture-proof.

11, tolerance mains fluctuations are very competent：The insulation performance of ceramic condenser can bear twice of volume the short time Constant voltage will not puncture, and the present embodiment by the outstanding pressure-resistant performance of ceramic condenser can bear be more than 300V supply voltage not Damage.

12, non-impact current, sparkling operation：Extremely simple impedance current limliting principle, in addition the current limliting of iron core reactor Effect so that its inrush current is ten parts of prior art Switching Power Supply less than 2 times of rated current, can be direct Flicker intermittent duty.

13, extremely cheap tunable optical driving power is provided：The impedance constant current principle of the present embodiment is allowed to have born External dimmer ability, by series impedance, capacitance or change input voltage as long as external, can easily change brightness, It can not possibly cause to flicker.

14, new technical solution is provided for LED constant current control technology field：It is that one kind being totally different from existing semiconductor The novel control program of electronic technology provides a kind of distinguished brand new technical scheme for LED control technology fields.

15, small, light-weight：Machine volume weight of the present invention is less than in same power fluorescent lamp ballast, with existing master The LED drive power of stream is suitable or smaller.

16, scrap products recovery value is big, environmental pressure is small：It is not difficult to find out from circuit structure, the present embodiment overwhelming majority Weight concentrates on iron inductance and ceramic condenser, wherein most substances are that iron, copper, aluminium, nickel etc. are recyclable, nonhazardous Metal simple-substance, it is big to scrap rear recovery value, even if properly recycling, will not cause environment larger harm.

Fig. 4 is the circuit diagram of second embodiment of the invention, also by multi-layer ceramic capacitance C1 and an iron inductance L1 group At, multi-layer ceramic capacitance C1 and iron inductance L1 are connected in series between driven LED light group and power frequency AC input terminal, Rectifier bridge D1 is connected between LED light group and power frequency AC, after the exchange side of rectifier bridge D1 is connected with multi-layer ceramic capacitance C1 Power frequency AC input terminal is connect, the DC side of rectifier bridge D1 is connect with the LED light group driven, and iron inductance L1 is series at whole The exchange side for flowing bridge D1, is made of gas-discharge lamp impedance type Inductive ballast；DC side then parallel filtering capacitor C2.In addition There are one overvoltage protection device R1 is in parallel with multi-layer ceramic capacitance C1；And a temperature switch or thermal protector S, temperature Switch or thermal protector S are contacted with overvoltage protection device R1 appearances, and are connected with power frequency AC input terminal；In addition also have One overcurrent protective device F connects with power frequency AC input terminal.

The principle of the embodiment is identical as embodiment one, becomes also with the capacitive reactance that multi-layer ceramic capacitance bias effect generates Change and coordinate with iron inductance, automatically controls output current, play the role of providing constant current, the Selection and Design of element for LED Method is also identical as embodiment one, is mainly characterized by the present embodiment and has also installed rectifier bridge D1, will be exchanged by rectifier bridge D1 Current transformation is DC current, can directly drive one group of unidirectional LED light group, without anti-using two groups to embodiment one To LED light group in parallel, and by the flat waves of filter condenser C2 in parallel, quite stable direct current can be provided to LED Stream, and eliminate stroboscopic.Although the present embodiment also uses the flat wave of electrolytic capacitor, since the present invention works in power frequency, unlike existing There is technology Switching Power Supply to will produce a large amount of high frequency ripples, therefore the electrolytic capacitor filter itself of the present invention hardly generates heat, therefore Service life is also extremely long, will not become service life bottleneck as the electrolytic capacitor in Switching Power Supply.Discharge resistance R2 is postboost for releasing Capacitance residual voltage, for current-limiting resistance R5 for limiting short circuit or dash current, protection LED light group is same as the prior art.

The iron inductance of the present embodiment is made of gas-discharge lamp impedance type Inductive ballast, it is known that gas discharge The impedance type Inductive ballast of lamp is exactly an iron inductance, and for 220V network voltages, specified terminal voltage is in 140- Between 205V, for rated current between 0.15-10A, which can effectively inhibit the harmonic wave of circuit generation, and energy substantially Ceramic condenser is set to be operated in close in the constant current curved section of rated voltage, therefore using the Inductive ballast generation of certain current specification Feasible for inductance of the present invention, in recent years as the LED energy-savings of a large amount of fluorescent lamps are transformed, a large amount of Inductive ballasts are given up It abandons, and Inductive ballast performance itself is stable, the service life is extremely long, iron inductance of the invention can directly utilize the electricity of gas-discharge lamp Feel ballast, is utilized in this way, a large amount of Inductive ballasts discarded originally are repeatable, not only saving a large amount of iron copper etc. has coloured gold The green circulatory ecology for belonging to resource, can also constituting LED reducing energy consumptions, waste and old light source electric appliance regeneration, has further played this The environmental benefit of invention is further greatly reduced with season manufacturing cost, because iron inductance L1 is that cost is highest in the present invention One component.

The present embodiment is in parallel with multi-layer ceramic capacitance C1 provided with an overvoltage protection device R1, to absorb overvoltage, Protect ceramic condenser；One temperature switch contacted with overvoltage protection device or thermal protector S, the temperature switch or temperature-sensitive are protected Shield device is connected with power frequency AC input terminal, is used for short-circuit protection, when the output terminal shortcircuit of the present embodiment, ceramic condenser C1 Both ends will appear higher overvoltage, by overvoltage protection device absorb overvoltage after, overvoltage protection device will largely be sent out Heat cuts off the input of AC power to make the temperature switch S contacted reach operating temperature threshold value, plays short-circuit guarantor Shield act on, in addition when entire driving power when the temperature is excessively high, the temperature switch also can action power dump, play overheating protection work With the temperature switch can be by the replacements such as thermal protector or PPTC self- recoverage protectors, and principle is identical, is routinely selected The temperature switch or rated current of 80-120 degree can reach effect slightly larger than the common thermal protector of the specified input current of circuit Fruit.Since the short circuit of the present invention has hard contact temperature switch or the spontaneous realization of PTC temperature-sensitive elements with overheating protection, controlled with using The prior art of coremaking piece software realization is compared, and is had the advantages that simple in structure, reliability is high, is not easy to malfunction.Over current protection Shield device F connects with power frequency AC input terminal, is used for the total overcurrent or short-circuit protection of entire driving circuit, further promotes electricity The safety in source.

The ceramic condenser C1 of the present embodiment be connected by multiple multi-layer ceramic capacitances it is multigroup, after every group of serial fuse F1, Multigroup again to compose in parallel, the rated blowing-current of fuse F1 is less than whole group multi-layer ceramic capacitance C1 rated current virtual values.This The purpose of sample is, once a ceramic condenser component breakdown, series connection with it another may also over-voltage breakdown, although at this time By the metering function of iron inductance, LED light group can still be lighted, but power supply loses constant current ability, due to fuse F1's It accesses, the ceramic condenser of this group of failure is just removed isolation at this time, plays constant current by remaining several groups of ceramic condensers, can for guarantee By fusing, the blowout current of fuse F1 is less than the rated current of entire ceramic condenser group C1, although output current can slightly subtract It is small, but entire power supply still has constant current effect, and other performance indicators will not decline, and embody self-healing function.

Further to consolidate lightning protection properties, the present embodiment is also connected to fuse F2 in ac power input end and is protected with overvoltage Device R3 is protected, is connected between the phase line of ac power input end, zero curve, the advanced protection of overvoltage Intruding wave is used for, due to fusing The access of device F2, so that it may entire power supply short circuit failure, overvoltage protection device caused by overvoltage protection device aging breakdown be avoided to hit By fuse F2 fusing excisions after wearing, the normal work of power supply can be unaffected, and certainly to reduce the cost, F2 can also be saved, Or shared overcurrent protective device F, overvoltage protection device R3 also can be by TVS diode, gas-discharge tubes etc. as the prior art Instead of parameter selection method is also same as the prior art.

It is clear that the present embodiment similarly with embodiment one have it is of low cost, reliability is high, the service life is super Long, resistance to thunder ability is strong, have temperature-compensating, have self-healing ability, using scrapping element resources, reduce grid loss, without electricity Magnetic disturbance, simple production process environmental protection, tolerance mains fluctuations ability be strong, convenient for recycling after flickering or dim operation, scrapping It is worth the advantages that big.

Fig. 5 is the circuit diagram of third embodiment of the invention, also by multi-layer ceramic capacitance C1 and an iron inductance L1 group At multi-layer ceramic capacitance C1 is connected between driven LED light group and power frequency AC input terminal, and LED light group is handed over power frequency Rectifier bridge D1 is connected between galvanic electricity source, the exchange side of rectifier bridge D1 is connected and is followed by with multi-layer ceramic capacitance C1, decompression capacitor C3 Power frequency AC input terminal, the DC side of rectifier bridge D1 are connect with the LED light group driven, and iron inductance L1 is series at rectification The DC side of bridge D1.It connects with power frequency AC input terminal there are one overcurrent protective device F, multi-layer ceramic capacitance C1 is same Also it is composed in series with fuse F1 by the series connection of multigroup multi-layer ceramic capacitance, again.

The principle of the embodiment is identical as embodiment one, two, the appearance generated also with multi-layer ceramic capacitance bias effect Resistanceization coordinates with iron inductance, automatically controls output current, plays the role of providing constant current for LED, the present embodiment The DC side in rectifier bridge is arranged in iron inductance, naturally it is also possible to is made of gas-discharge lamp impedance type Inductive ballast, iron core Inductance is connected on DC side, can equally play the role of inhibiting harmonic wave and dash current, but the inductor of DC side is in exchange side It is smaller to form reactive power, the terminal voltage of ceramic condenser cannot be made to significantly increase, to make the constant current reduced performance of ceramic condenser, But advantage is that the terminal voltage of ceramic condenser C1 is just smaller, may be used the lower ceramic condenser of pressure voltage to reduce at This, in addition adds concatenated decompression capacitor C3, can further decrease the terminal voltage of ceramic condenser C1, even if output terminal shortcircuit, The voltage at ceramic condenser both ends will not increase very much, can utilize the resistance to ceramic condenser forced down in this way, can not also need specially The overvoltage protection device of door is protected, and residual charges of the discharge resistance R4 for decompression capacitor C3 discharges, this embodiment is another Outer advantage is, the DC current for flowing through LED light group can be made to tend to be steady by iron inductance stable DC side electric current, To avoid again the increased cost of parallel filtering capacitance institute.In addition the present embodiment is also provided with overcurrent protective device F and is handed over power frequency Power input series connection is flowed, the total overcurrent or short-circuit protection and overvoltage protection device R3 for entire driving circuit are for electricity The protection of the overvoltage Intruding wave of source input terminal further promotes the safety and reliability of power supply.Overvoltage protection device R3 is removed It is replaced using TVS diode etc. outer, the compound varistor for having breakdown protection function can also be used, so that it may save specially The fuse of door.

It is clear that the present embodiment similarly with above-mentioned other embodiment have it is of low cost, reliability is high, the longevity Life overlength, resistance to thunder ability is strong, have self-healing ability, has temperature compensation capability, using scrapping element resources, reduce power grid damage Consumption, without electromagnetic interference, simple production process environmental protection, tolerance mains fluctuations ability it is strong, convenient for flickering or dim operation, scrap The advantages that recovery value is big afterwards.

Fig. 6 is the circuit diagram of four embodiment of the invention, also by multi-layer ceramic capacitance C1 and an iron inductance L1 group At being connected to Industrial Frequency Transformer T between LED light group and power frequency AC input terminal, the vice-side winding of Industrial Frequency Transformer T connects rectification The exchange side of bridge D1, multi-layer ceramic capacitance C1 are series between the vice-side winding of Industrial Frequency Transformer T and rectifier bridge exchange side, rectification The DC side of bridge D1 is connect with the LED light group driven, and iron inductance L1 is series at the primary side winding of Industrial Frequency Transformer T and exchanges Between power input.It connects with power frequency AC input terminal there are one overcurrent protective device F.Multi-layer ceramic capacitance C1 is same Sample can be also composed in series by multigroup multi-layer ceramic capacitance connection in series-parallel or grouping with fuse.

The principle of the embodiment is identical as above-mentioned other embodiment, is generated also with multi-layer ceramic capacitance bias effect Capacitive reactance variation coordinates with iron inductance, automatically controls output current, plays the role of providing constant current, the present embodiment for LED An Industrial Frequency Transformer is used, voltage is reduced by transformer, and be isolated with ac high-voltage power grid, can be provided to LED light group Safer low-voltage power supply, primary side or secondary side, ceramic condenser C1 in transformer, which is arranged, in iron inductance L1 equally can also set The primary side in transformer T or secondary side are set, but is arranged on secondary side, voltage is relatively low, and the price of low pressure ceramic capacitance is usually less than height The specification of pressure can reduce the cost of ceramic condenser.Iron inductance since the short-circuit impedance of transformer can provide a part of inductance value, Therefore its volume can reduce 15-30% or so with inductance value compared with no transformer, and gas can also be used in certain iron inductance Discharge lamp Inductive ballast may also be arranged on the DC side of rectifier bridge.The present embodiment be equally also provided with overcurrent protective device F with Power frequency AC input terminal is connected, and is used for the total overcurrent or short-circuit protection of entire driving circuit, is further promoted the peace of power supply Quan Xing.Since transformer tolerance overvoltage ability is stronger and Lightning Incoming Wave is difficult to be transmitted to low-pressure side by transformer, because The overvoltage protection of this present embodiment does not need the protection of overvoltage protection element substantially with regard to fairly simple.

It should be noted that the inductance that the present embodiment is provided due to Transformer Short Circuit Impedance, if to harmonic wave index request It is not high, iron inductance L1 can be also saved, but essence is identical, and iron is realized only with the short-circuit impedance of transformer itself The function of core inductance L1 reduces volume again if harmonic wave index should be improved, and transformer T can be also designed as to leakage field transformation Device plays the filter action of iron inductance L1 using the larger leakage reactance of leakage transformer, can be in the base for saving iron inductance L1 Reach harmonic wave forcible authentication standard on plinth.In addition rectifier bridge can also make change according to transformer secondary discernment method, such as use Voltage multiplying rectifier bridge, double diode full-wave rectifying circuit replace common rectifier bridge, or are formed using common cathode common anode Schottky diode Low-loss rectifier bridge etc., these conventional flexible means are equal completely with technical scheme of the present invention.

It is clear that the present embodiment similarly with other embodiments of the invention have it is of low cost, reliability is high, Overlong service life, resistance to thunder ability are strong, have self-healing ability, using scrap element resources, reduce grid loss, without electromagnetic interference, It the advantages that simple production process environmental protection, tolerance mains fluctuations ability strong, convenient for flicker or light modulation operation, is also equipped in addition The performance of the primary and secondary electrical isolation more better than prior art isolated form driving power, because the present embodiment does not have electromagnetism dry It disturbs, anti-interference capacitor, therefore its electrical isolation ability need not be set between the former secondary side of high frequency transformer as the prior art Also it is much better than the isolated power supply of the prior art, in the application scenario for needing primary and secondary to be strictly isolated, the present embodiment advantage ten is clearly demarcated It is aobvious.

Fig. 7 is the circuit diagram of fifth embodiment of the invention, is also made of multi-layer ceramic capacitance C1 and iron inductance L1, more Layer ceramic condenser C1 and iron inductance L1 is connected in series between driven LED light group and power frequency AC input terminal, multilayer Ceramic condenser C1 is composed in series by several multi-layer ceramic capacitances, since the bias constant current of multi-layer ceramic capacitance acts on, once one Breakdown, remaining to remain to that output current is maintained not increase very much, the constant current performance of circuit remains to be protected；LED light group and work Rectifier bridge D1 is connected between frequency AC power, the exchange side of rectifier bridge D1 is connected with multi-layer ceramic capacitance C1 is followed by industrial-frequency alternating current Source input terminal, the DC side of rectifier bridge D1 are connect with the LED light group driven, iron inductance L1 have two groups of windings, two around One end of group is connected with power frequency AC input terminal, and is series at the exchange side of rectifier bridge D1；DC side then filter in parallel Wave capacitor C2 and discharge resistance R2, filter condenser C2 use nonpolarity thin film capacitor, realize longer than electrolytic capacitor In the service life, in addition there are overvoltage protection device R1 to connect with overcurrent protective device F with power frequency AC input terminal, and finally also one A continued flow resistance R6, it is in parallel with ac power input end, when being used for SCR light regulation, it is not turned on to thyristor gating circuit offer Trigger circuit charging current in period is identical as the continued flow resistance of phase-controlled dimming power supply of the prior art.

The principle of the embodiment is identical as other embodiment, the capacitive reactance generated also with multi-layer ceramic capacitance bias effect Variation coordinates with iron inductance, automatically controls output current, plays the role of providing constant current, the iron of the present embodiment for LED Core inductance is made of two groups of windings, is connected at ac power input end, the purpose for the arrangement is that lightning protection can be played preferably Effect, it is understood that the wave head frequency of Lightning Incoming Wave is very high, and the huge inductance value of iron inductance can play Lightning Incoming Wave To prodigious weakening effect, the winding of iron inductance is divided into two in this way, series connection and AC power arrival end, can have respectively Effect absorb relatively, the overvoltage Intruding wave of zero curve over the ground can play extremely outstanding lightning protection effect if cooperation lightning protection component Fruit.Although simple rigid structure of the present invention itself itself has inborn lightning protection capability, mountain area, minefield etc. distinguishingly Area uses, then the present embodiment can play lightning protection effect more outstanding, and after tested, the present embodiment model machine can continuously be born The surge impact voltage tens times of phase --- ground, zero --- 15KV, 1ms between ground are without damage, and integrated lightning protection effect is higher than existing Tens times of technology Switching Power Supply product, the year broken by lightning rate in practical application in multi-thunder area is only one thousandth, damage Probability is only 1 percent or so of prior art Switching Power Supply.To further increase lightning protection properties, the present embodiment is in alternating current Source input terminal and DC output end are connected to fuse F2 and overvoltage protection device R3, and above-mentioned two element is divided into three groups, and one Group is connected between ac power input end phase line, zero curve, and another group is connected between phase line or zero curve and earthing of casing end, last Group is connected between DC output end positive and negative anodes, is used for the full protection of overvoltage Intruding wave, the effect of fuse F2 and embodiment Two is identical.Certain overvoltage protection device R3 equally also can be by replacements such as TVS diode, gas-discharge tubes.The present embodiment is equally Provided with an overvoltage protection device R1 is in parallel with multi-layer ceramic capacitance C1 and a temperature contacted with overvoltage protection device Switch S is used for short-circuit protection, plays the role of short-circuit protection, temperature switch S equally also can be by the provided as one homogeneous element structure such as thermal protector At overcurrent protective device F connects with power frequency AC input terminal, is used for the overcurrent or short-circuit protection of entire driving circuit.

It is clear that the present embodiment similarly with embodiment one have it is of low cost, reliability is high, the service life is super Long, resistance to thunder ability is extremely prominent, have self-healing ability with temperature compensation capability, damages using scrapping element resources, reduce power grid Consumption, without electromagnetic interference, simple production process environmental protection, tolerance mains fluctuations ability is strong, it is big to scrap rear recovery value, convenient for dodging The advantages that bright or light modulation operation.

Fig. 8 is the circuit diagram of sixth embodiment of the invention, is also made of multi-layer ceramic capacitance C1 and iron inductance L1, and Decompression capacitor C3 partial pressures are added as embodiment three, to reduce the pressure voltage of ceramic condenser C1 to further decrease into This, the multi-layer ceramic capacitance C1 of the present embodiment is divided into three groups, three groups connect respectively with the contact of switch controller S1 after again with Iron inductance L1 is connected in series between driven LED light group and power frequency AC input terminal, in this manner it is possible to by switching The contact of controller S1 switches, to select different ceramic condenser groups, to realize incremental dimming or switch, with external dimmer side Formula is compared, and is had many advantages, such as that light modulation loss is small, is not likely to produce harmonic wave, the design method of switch controller S1 is very flexible, can tie It closes the prior art and is designed to external signal, if carrier wave, WIFI, Bluetooth transmission control or sensor automatically control, or directly lead out Catcher moves switching circuit, it might even be possible to and directly it is divided into multiple taps and draws, output current size is directly controlled using external cabling, To realize driving power light modulation, the diversification of control mode, the present embodiment is additionally provided with flat wave inductor L2 in addition, for limiting The dash current of short circuit current or LED element abnormal conditions can also assist in filtering, improve stroboscopic.The principle of circuit other parts It is identical with other embodiment.Certainly, the present embodiment can also be by being divided decompression capacitor C3 or iron inductance L1 Group connection in series-parallel, setting switching device contact draw tap, realize light modulation or switch control, principle is identical.

It is clear that the present embodiment similarly with embodiment one have it is of low cost, reliability is high, the service life is super Long, resistance to thunder ability is extremely prominent, have self-healing ability with temperature compensation capability, damages using scrapping element resources, reduce power grid Consumption, without electromagnetic interference, scrap that rear recovery value is big, simple production process is environmentally friendly, tolerance mains fluctuations ability is strong, convenient for dodging The advantages that bright or light modulation operation.

It should be appreciated by those skilled in the art that those skilled in the art are combining the prior art and above-described embodiment can be with Realize the change case, this will not be repeated here.Such change case does not affect the essence of the present invention, not superfluous herein It states.

Presently preferred embodiments of the present invention is described above.It is to be appreciated that the invention is not limited in above-mentioned Particular implementation, wherein the equipment and structure be not described in detail to the greatest extent are construed as giving reality with the common mode in this field It applies；Any technical person familiar with the field, without departing from the scope of the technical proposal of the invention, all using the disclosure above Methods and technical content many possible changes and modifications are made to technical solution of the present invention, or be revised as equivalent variations etc. Embodiment is imitated, such as increases reactive-load compensation element, increase redundancy with multiple element connection in series-parallel, certain conventional control device of plugging into Etc., this is not affected the essence of the present invention, and the "a" or "an" before element of the present invention is not excluded for occurring multiple this Element, therefore, every content without departing from technical solution of the present invention according to the technical essence of the invention does above example Any simple modifications, equivalents, and modifications, still fall within technical solution of the present invention protection in the range of.

Claims

1. a kind of multi-layer ceramic capacitance constant current driver circuit for LED, which is characterized in that include：

One multi-layer ceramic capacitance (C1) and an iron inductance (L1), the multi-layer ceramic capacitance (C1) and the iron inductance (L1) it is connected in series between driven LED light group and power frequency AC input terminal；

Wherein, the multi-layer ceramic capacitance (C1) has Dc bias effect, appearance under the conditions of maximum allowable Dc bias 70% of amount no more than its nominal capacity；Both end voltage of the multi-layer ceramic capacitance (C1) in specified max-flow overcurrent has Valid value is not less than the 25% of rated supply voltage virtual value；The pressure voltage of the multi-layer ceramic capacitance (C1) is not less than rated power supply The 20% of voltage peak；Both end voltage virtual value of the iron inductance (L1) in specified max-flow overcurrent is not less than specified The 20% of supply voltage virtual value.

2. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that the multi-layer ceramics Capacitance (C1) is made of multiple multi-layer ceramic capacitance series, parallel or connection in series-parallel.

3. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that the multilayer pottery Porcelain capacitance (C1) be connected by multiple multi-layer ceramic capacitances it is multigroup, after every group of serial fuse (F1), then it is multigroup compose in parallel, institute The rated blowing-current for stating fuse (F1) is less than whole group multi-layer ceramic capacitance (C1) rated current virtual value.

4. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that the iron inductance (L1) iron core is equipped with Unequal distance air gap, and the impedance value in rated maximum current is 40-the 100% of its initial impedance value.

5. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that the iron inductance (L1) include gas-discharge lamp impedance type Inductive ballast.

6. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that described driven Be connected to rectifier bridge (D1) between LED light group and power frequency AC input terminal, the exchange side of the rectifier bridge (D1) with it is described more Layer ceramic condenser (C1) series connection is followed by power frequency AC input terminal, the DC side of the rectifier bridge (D1) and the LED driven Lamp group connects, and the iron inductance (L1) is connected with the exchange side of the rectifier bridge (D1) or DC side.

7. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 4, which is characterized in that the rectifier bridge (D1) DC side parallel has filter condenser (C2) and discharge resistance (R2).

8. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that described driven Industrial Frequency Transformer (T) is connected between LED light group and power frequency AC input terminal.

9. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that described driven Decompression capacitor (C3) is serially connected between LED light group and power frequency AC input terminal.

10. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that there are one further including Overvoltage protection device (R1), the overvoltage protection device (R1) are in parallel with the multi-layer ceramic capacitance (C1)；One temperature switch Or thermal protector (S), the temperature switch or thermal protector (S) are contacted with the overvoltage protection device (R1) appearance, and It connects with power frequency AC input terminal.

11. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that there are one further including Overcurrent protective device (F), the overcurrent protective device (F) are connected with power frequency AC input terminal.

12. multi-layer ceramic capacitance constant current driver circuit for LED according to claim 1, which is characterized in that there are one further including Overvoltage protection device (R3), the overvoltage protection device (R3) are parallel to power frequency AC after connecting with a fuse (F2) Input terminal, or be parallel between power frequency AC input terminal and earthing of casing end.