CN204829797U - Extension current drive's LED electric light source life's device - Google Patents

Abstract

The utility model provides an extension current drive's LED electric light source life's device, still is connected with the protective film piece including the power, drive module and the load LED banks that connect gradually on load LED banks, load LED banks includes LED chip and additional LED chip, effectively reduce effectively the compensate measure of LED junction temperature in order to prolong its life -span and the corresponding luminous quantity reduction problem of bringing to can obtain higher luminous efficacy under lower operating temperature state.

Description

A kind of device extending LED electrical light source service life that electric current drives

Technical field

The utility model belongs to light sources technical field, and particularly a kind of light emitting source that utilizes is in underloading duty to reduce caloric value and then to reduce junction temperature and the device extending LED electrical light source service life that electric current drives.

Background technology

Along with the enforcement of energy-saving and emission-reduction state basic policy, the lighting load accounting for power consumption 15% more and more adopts light emitting diode (solid LED, be called for short LED) lamp as electric light source, this is because LED itself to have luminous efficiency as light emitting diode high, the life-span such as to grow at the significant performance advantage.But up to now because the bad PN junction junction temperature that causes of dispelling the heat raises thus causes significantly decline service life having become its major technology bottleneck applied.Particularly for the LED light source being applied in vcehicular tunnel, road lighting field, because work under bad environment is changeable, installation site is remote and be in the unfavorable factors such as high-altitude, makes maintenance and changes all very difficult.How on natural heat dissipation mode basis, effectively to reduce die temperature further, thus realize the prolongation of light source life and the raising of luminous efficiency, keep in repair between the minimizing operating period and extend the replacement cycle, having great practical value and social effect.

According to A Leiniusi rule, LED junction temperature (being approximately die temperature) often reduces by 10 DEG C of its life-spans and will extend more than 2 times, and test proves: junction temperature is higher, and electro-optical efficiency is lower, namely often reduces by 10 DEG C of its electro-optical efficiencies and improves more than 8%; More frighteningly high junction temperature also will bring expendable light decay.The ideal operation state of 100000 hours can be reached as controlled the life-span of light decay 70% 65 DEG C time when junction temperature.The severity although LED generates heat unlike incandescent light source, but electric current is by producing certain Joule heat too while PN junction and connecting circuit thereof, light sent in addition causes all launching owing to producing refraction at encapsulating material interface, is also all consumed with form of heat.In a word according to law of conservation of energy, if the LED electrical light source electro-optical efficiency in current engineer applied is 35%, then remaining 65% is all for conversion into heat and causes knot core temperature to raise.Such as forward voltage is 3V, electric current is 1000mA(and 3W power) light emitting diode send outside the luminous flux of 300Lx, so also have 2W convert the rising that heat causes junction temperature to.Under LED light source normal operating conditions, these heats utilize natural heat dissipation method to reduce junction temperature usually, although LED light source have employed multiple natural heat dissipation measure and corresponding frame for movement raising radiating effect at present, its result is also not so good as people's will; Particularly after summer, environment temperature rose, the dust etc. fallen between fin gap under severe outdoor work environment inevitably will make its natural cooling effect then can be poorer, thus cause die temperature to raise further, and then have a strong impact on the service life of illuminating street lamp.Test proves, when junction temperature of light emitting diode (die temperature) is in more than 135 DEG C of critical-temperatures, its service life will be had a strong impact on, the factor such as aging under considering the transparent encapsulation material condition of high temperature again, common engineering requires die temperature is controlled the impact that as far as possible reduces below 85 DEG C the life-span.So how effectively to reduce its die temperature effectively extend the key technology that its service life just becomes street lighting class high-power LED light source.

Because adopt natural heat dissipation mode to be that in practical application, LED light source is uniquely effectively selected, and the heat that thermal source produces under coming from tube core normal operating conditions, comprise and flow through Joule heat and packed material interface that electric current produces because the heat etc. that converts to of the light that reflects of dielectric constant difference.So at the various cooling measures taked at present to reduce junction temperature: comprise the thermal resistance by reducing light emitting diode and fin immobilization material; Increasing heat radiation area as far as possible; Adopt dielectric constant to be above close to perfect means and measure close to the encapsulating material of illuminator to reduce the existing science and technology bases such as boundary reflection as far as possible, but still can not reach more satisfactory radiating effect situation.

Summary of the invention

For overcoming the deficiency existing for above-mentioned prior art, the purpose of this utility model is to provide a kind of device extending LED electrical light source service life that electric current drives, and has structure simple, effectively reduces LED junction temperature, extends the feature in light source service life.

For achieving the above object, the technical solution adopted in the utility model is: a kind of device extending LED electrical light source service life that electric current drives, comprises the power supply, driver module and the LED group that connect successively, LED group is also connected with protection module; Described load LED lamp group comprises LED chip and additional LED dies.

The DC current source needed for 220 volts of AC rectification apparatus for converting that civil power can provide by described power supply.

Described power supply is connected with solar panel, and power supply is connected with load LED lamp group.

Described driver module 2 is made up of DC-DC circuit and constant current driver circuit for LED.

Described protection module includes over-temperature protection device and overvoltage protection.

Described power acquisition constant-current source Is, directly additional LED dies in parallel on the basis of former LED chip.

The beneficial effects of the utility model are:

The utility model is under the prerequisite not affecting street lamp main performance, by reducing the method producing heat from source, the target of junction temperature under realization effective reduction LED normal operating conditions, make its summer exceedingly odious working environment and temperature conditions under, LED light source junction temperature still can be in desirable die temperature.

The utility model for LED type street lamp install and maintenance subsequently and trial period to the extremely inconvenient feature of rear replacing, still cannot obtain more satisfactory junction temperature according to adopting at present various external structure in natural heat dissipation mode and become the present situation affecting its life-span principal element, trace it to its cause is that this natural heat dissipation structure and encapsulating material thereof have been close to improve and can dig without potentiality on prior art performance basis, if so can the heat reducing pyrotoxin generation under Specifeca tion speeification condition be being ensured, to be by reducing the effectively life-extending effective way improving electro-optical efficiency of junction temperature mode simultaneously undoubtedly.It is made to be in duty-light condition lower than rated power all the time particular by reducing the mode of each chip operation electric current, thus produce less heat and after natural heat dissipation, reach the effect effectively reducing junction temperature, and realize solid light source working life simultaneously and effectively extend and improve the target of electro-optical efficiency; And the problem that the output effective power that causes thus reduces, then to make up by suitably increasing the method for installing some LED chip because in street lamp the space of installing some LED chip more be existence with affluence, be in this way feasible.Although cause street lamp cost increase owing to installing LED chip more, with in use procedure because junction temperature is high cause light decay thus compared with the huge administrative expenses frequently changing street lamp, the former just seems insignificant, thus makes the method have very high practical value.

The direct current boosting that power supply provides by DC-DC circuit or the rated voltage be depressurized to needed for LED group, a constant operating current lower than rated current is provided to each LED chip in LED group again by constant current driver circuit for LED, each LED chip is made to be in duty lower than rated power, thus reach effectively reduction LED junction temperature, the target increased the service life.

The utility model, while reducing LED junction temperature, increasing the service life, can also improve LED chip electro-optical efficiency, and increase luminous quantity, slow down the aging of encapsulating material epoxy resin.

The utility model has not only been found one and has effectively been reduced LED junction temperature to extend effective Compensation measures of its life-span and the corresponding luminous quantity minimizing problem brought, and the more important thing is obtain higher luminous efficiency under lower operating temperature state, thus theory and practice combines the cost performance that upper entirety improves LED light source.

Accompanying drawing explanation

Fig. 1 is overall structure schematic diagram of the present utility model.

Fig. 2 is the electrical block diagram of the utility model LED group.

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, illustrate the utility model further, the present embodiment is implemented under premised on technical solutions of the utility model, should understand these embodiments and only be not used in restriction scope of the present utility model for illustration of the utility model.

As illustrated in fig. 1 and 2, the new equipment that a kind of LED electrical light source of driven with current sources increases the service life, comprises the power supply 1, driver module 2 and the load LED lamp group 3 that connect successively, load LED lamp group 3 is also connected with protection module 4.

The DC current source needed for 220 volts of AC rectification apparatus for converting that civil power can provide by described power supply.

Described power supply is connected with solar panel, and power supply is connected with load LED lamp group 3, for load LED lamp group provides DC current source.

Described driver module 2 is made up of DC-DC circuit and constant current driver circuit for LED; The direct current boosting that power supply provides by DC-DC circuit or the rated voltage be depressurized to needed for load LED lamp group 3, a constant operating current lower than rated current is provided to each LED chip in load LED lamp group 3 again by constant current driver circuit for LED, each LED chip is made to be in duty lower than rated power, thus reach effectively reduction LED junction temperature, the target increased the service life.

Described LED group is in the duty lower than rated power, if do not increase the quantity of LED chip, then there will be the situation that this lamp brightness of illumination meets technical requirement not.In actual applications, in the whole shell of street lamp, there is the space of installing more LED chip, so make up accordingly brightness of illumination minimizing by the quantity suitably increasing LED chip.

The rising of street lamp cost can be caused owing to installing LED chip more, but with in use procedure because temperature affect LED street lamp service life short and frequently change street lamp great expense compared with, the former just seems very little.So there is very large practical value.

Described protection module includes over-temperature protection device and overvoltage protection.

Described device, while reducing LED junction temperature, increasing the service life, can also improve LED chip electro-optical efficiency, and increase luminous quantity, slow down the aging of encapsulating material epoxy resin.

Described power acquisition constant-current source Is, directly additional LED dies (3-2) in parallel on the basis of former LED chip (3-1).

When constant-current source Is drives load LED lamp group (3), the load that directly additional LED dies (3-2) in parallel forms on the basis of former LED chip (3-1), not only achieve whole electric light source load and be in underloading duty, and compensate for again reduced luminous power, obtain higher luminous efficiency under being in low junction temperature condition simultaneously.

In fig. 2, original load LED lamp group comprises LED chip 3-1.After increasing additional LED dies 3-2 with parallel way again, for current source Is, both made whole load LED lamp group 3 be in light condition, and compensate for again the luminous power caused thus and reduce.And the more important thing is the reduction of junction temperature, electro-optical efficiency is improved.

Below by way of a specific embodiment, the utility model is described:

, the road of wide 10 meters, usual pole height is 6 meters, and street lamp installing space is 20 meters.And in order to reduce expense, be all take to use monolateral pattern of lighting on the low-pressure electric pole of roadside usually, then need to select 90W high-power LED street lamp could meet the lighting requirement of street road.As shown in Figure 2, the 90WLED street lamp of certain manufacturer production domestic is made up of 90 1W high-power LED chip 3-1.Wherein, every ten LED chip are connected into one group, and 90 chips, are just divided into nine groups, are often interconnected by parallel way rear by driven with current sources between group altogether.If each LED chip rated voltage is 3.3V, rated current is 0.35A, for ensureing to work under nominal power, need for lamp group 3 provides the power drives of the voltage of 3.3V*10=33V and the electric current of 0.35A*9=3.15A, DC current source is adopted to drive as preferred plan at this, because directly adopt photovoltaic power generation plate as power supply in current many situations, photovoltaic power generation plate is then close to desirable current source.When working under LED chip rated power state, its junction temperature is up to 85 DEG C, according to 70% light decay formula:

As calculated, the LED street lamp of this manufacturer production is only 14,000 hours service life.Be calculate for 12 hours according to street lamp working time every day, its service life is only 3 years, and in actual use procedure, and particularly summer, radiating effect poorlyer caused its life-span shorter.This at most just need be installed on remote location to these at every 3 years and the LED street lamp being in high-altitude is once changed comprehensively with regard to meaning, and the workload of this replacing light source is not only very large, and very inconvenient, thus bring very large difficulty to the management maintenance of street lamp.

If but utilize the utility model device, only need in load LED lamp group 3 three groups of additional LED dies 3-2 being similarly 10 of 1W series connection mutually in parallel, other module does not do any change.Due to the LED chip of existing 12 groups of parallel connections, therefore the drive current of original 3.15A has been divided into 12 equal portions, and reduce to 3.15A/12=0.26A by the electric current of each LED chip, voltage still keeps 3.3V.So each LED chip operating current reduces to 75% of rated current, power also just reduces to 75% of rated power naturally.According to the data that whole world Cree company of the famous semiconductor maker U.S. provides, when LED chip is operated in 75% of rated current, its junction temperature can drop to 75 DEG C.By known (thousand hours light decay rates when junction temperature is 75 DEG C of above-mentioned 70% light decay formula get 4%), now suddenly increase to 30,000 hours the service life of LED.Same every day lights 12 hours, and this LED street lamp can use 7 years, and life is many to twice, greatly reduces replacement frequency.

The each street lamp of the utility model device is utilized to need increase by 30 1W high-power LED chips, each chip cost is 4 maos, altogether only need the cost of increase by 12 yuan, replacing street lamp number of times but can be made to be reduced to original half, and junction temperature reduction effectively raises electro-optical efficiency again.And change street lamp and need to expend the 90WLED street lamp that several are worth 550 yuan, the expense of manpower, machine resources when adding replacing, then considerably beyond the LED chip cost increased.So, the application of the utility model device is exchange maximum interests for minimum cost, from overall result of use, when disposable mounting cost has increased slightly, (many mounted LED lamps core causes cost to increase) makes life of product increase substantially, thus effectively reduce use cost, improve the cost performance of product.

The utility model extends the device in LED electrical light source service life, substantially improved based on the natural heat dissipation device of current LED light source and for when changing, very inconvenient illuminating street lamp be installed, reduced the heat of light source generation by the method reducing the operating current of each LED chip, realize effectively reducing junction temperature and also turn improve electro-optical efficiency while extending working life target; Because it is in the underloading duty lower than rated power, recycling increases the deficiency that part LED light source makes up gross output, the great power LED electric light source efficiently solving street lamp class loading, unloading operating difficulties from the combination of theory and practice applies in process the major technology bottleneck affecting the life-span, applies widely paved road for street lamp class great power LED electric light source.

This technology is applicable to the inconvenient LED street lamp class of use management under current heat dissipation technology condition, reduces the method for junction temperature and then reaches life-extending target of raising the efficiency, but be not limited to this application by reducing heat generation; Can also be applied to market huge other occasion such as LED display.

Claims (6)

1. extend the device in LED electrical light source service life that electric current drives, comprise the power supply (1), driver module (2) and the load LED lamp group (3) that connect successively, it is characterized in that, load LED lamp group (3) is also connected with protection module (4); Described load LED lamp group comprises LED chip (3-1) and additional LED dies (3-2).

2. a kind of device extending LED electrical light source service life that electric current drives according to claim 1, is characterized in that, the DC current source needed for 220 volts of AC rectification apparatus for converting that civil power can provide by described power supply.

3. a kind of device extending LED electrical light source service life that electric current drives according to claim 1, it is characterized in that, described power supply is connected with solar panel.

4. a kind of device extending LED electrical light source service life that electric current drives according to claim 1, it is characterized in that, described driver module (2) is made up of DC-DC circuit and constant current driver circuit for LED.

5. a kind of device extending LED electrical light source service life that electric current drives according to claim 1, it is characterized in that, described protection module (4) includes over-temperature protection device and overvoltage protection.

6. a kind of device extending LED electrical light source service life that electric current drives according to claim 1, is characterized in that, described power acquisition constant-current source Is, directly additional LED dies (3-2) in parallel on the basis of former LED chip (3-1).