CN107544037A

CN107544037A - A kind of LED lamp light decay fast calculates mode

Info

Publication number: CN107544037A
Application number: CN201610517063.3A
Authority: CN
Inventors: 范子英; 周永佳; 潘伟雄
Original assignee: GUANGZHOU GUJIA LAMP SCIENCE & TECHNOLOGY Co Ltd
Current assignee: GUANGZHOU GUJIA LAMP SCIENCE & TECHNOLOGY Co Ltd
Priority date: 2016-06-28
Filing date: 2016-06-28
Publication date: 2018-01-05

Abstract

The present invention is according to the luminous power of LED white light-emitting diodes and the physical characteristic of operating temperature, release a kind of LED illumination lamp light decay and fast calculate mode, only with 3 day time of 1 ∽ and easily mode, obtain the basic parameter of light fixture light decay measurement key element, the rate of change of operating temperature and luminous power is converted to, compares the rate of change of LED lamp light decay natural change law curve, calculates the trend and state of tested light fixture light decay change in advance, reach the effect of light fixture light decay measurement, saving of labor, time saving, low power consuming.Each product surveillance even can be implemented, be advantageous to science and implement character surveillance.

Description

A kind of LED lamp light decay fast calculates mode

Technical field

The present invention relates to a kind of LED lamp light decay measuring method, belong to LED illumination application field.

Background technology

The optical attenuation of LED illumination lamp is slow progressive formation, and the time that natural light decay measurement needs undergo is very long, especially It is LED technology possessed optical attenuation less the advantages of being compared with other illuminators, is accelerated despite the use of at this stage Simulation is measured and calculated mode using aging, and also to undergo thousands of hours just has result, and test period length, power consumption is big, costly, An other sample testing can only be done, the quality control and supervision to product turn into obstacle.

Light fixture is the carrier of lighting engineering, LED luminous power in light fixture, is influenceed and sent out by the various factors of composition light fixture Changing.The manner is advised according to the change of the intrinsic physical characteristic and operating temperature and luminous power of semiconductor white light-emitting diodes Rule；U=-33mV/10 DEG C of the forward voltage Δ of each illuminator, the performance parameter of L=-0.55lm/10 DEG C of luminous flux Δ, quilt Light fixture is measured with the forward voltage and light flux variations value of temperature change, is converted to the change influenceed by operating temperature Rate, because rate of change is bigger, reflect that the operating temperature of illuminator is higher, the change of caused luminous power is bigger, and optical attenuation is got over Seriously.The judgement of light decay degree is defined, and also to compare the light decay natural change law ginseng that inspection light fixture is surveyed by aging in thousands of hours Number, the reference value of rate of change is converted into, it is determined that the light decay of tested light fixture changes performance, judges the light decay variation tendency and journey of light fixture Degree, reach efficiently light decay measuring and calculating effect.

The content of the invention

1. measurement change value

It is U that tested light fixture, which measures illuminator cold conditions forward voltage in 20 DEG C ± 1 DEG C of environment temperature, start-up operation,_20℃, light Flux is L_20℃.It is U to be worked after light fixture to forward voltage after thermal steady state_{Heat 1}, luminous flux L_{Heat 1}, cold conditions and hot stable state two take It is change value that value, which is subtracted each other,.Temperature drops to initial value after being stopped, and it is second of U to carry out the steady measurement of heat again_{Heat 2}With L_{Heat 2}... ....

Change value；(first time) U_20℃-U_{Heat 1}=Δ U₁, L_20℃-L_{Heat 1}=Δ L₁

(for the second time) U_20℃-U_{Heat 2}=Δ U₁, L_20℃-L_{Heat 2}=Δ L₂

If second of measured value is differed no more than 1% with first time, Δ U can be considered₁=Δ U_{It is flat}, Δ L1=Δs L_{It is flat}It is no Then, third time is measured to average.

2. convert rate of change

Forward voltage rate of change；ΔU_{It is flat}/U_20℃× 100%=X_{U is put down}%

Light flux variations rate；ΔL_{It is flat}/L_20℃× 100%=X_{L is put down}%

The change value of the measurable electrical power of light fixture of constant-current supply driving, instead of the variable quantity of illuminator forward voltage Value, but measurement error influence caused by the change of current value must be excluded.

P_20℃-P_{Heat is flat}=Δ P_{It is flat} ΔP_{It is flat}/P_20℃× 100%=X_{P is put down}%

The determination of rate 3. natural light decays

Thousands of hours aging light decays of experience are surveyed a few money light fixtures of inspection, make the survey of above-mentioned forward voltage and light flux variations rate Amount, and environment temperature is pressed as the change values under 20 DEG C, 30 DEG C, 40 DEG C of each gear level states, drawing temperature and light decay change Rate curve, average value is obtained, and according to the requirement of relevant laws and regulations and standard to light decay, set suitable rate of change reference Value；Forward voltage is X_Uo%, luminous flux X_Lo%, the Scale criterion of light fixture light decay is calculated after being exactly after reference value determination, should Make every effort to precisely and close the requirement of relevant laws and regulations.

4. judge the state and acceptance value of light decay

It is required that the forward voltage rate of temperature change X of tested light fixture_{U is put down}%≤X_Uo%

Luminous flux rate of temperature change X_{L is put down}%≤X_Lo%.

Measurement and conversion mode more than reach LED lamp light decay efficiently measurement effect.

Brief description of the drawings

1 is light meter in figure, and 2 be that light-metering is popped one's head in, and 3 be integrating sphere light-metering mouth, and 4 be light fitting reflecting cover, and 5 be illuminator, and 6 are Power supply driver, 7 be lamp housing and heat dissipating housing, and 8 be temperature measuring gauge, and 9 be D.C. voltmeter, and 10 be ac power meter.

Embodiment

1 prepares；Each instrument, light fixture, the connection of light-measuring integrating sphere and position ornaments, light fixture light-emitting window are completed by accompanying drawing to align The light-metering mouth of integrating sphere, environment temperature are kept for 20 DEG C ± 1 DEG C, and now lamp outer casing monitoring temperature table shows same temperature.

2 cold conditions values are read；Connection working power is read in ten seconds；The numerical value of D.C. voltmeter 9 for measuring illuminator is U_20℃, the numerical value of light meter 1 is L_20℃。

3 hot steady-state values are read；Light fixture constant current-supplying in the case where keeping constant environment temperature continuously works, temperature measuring gauge 8, direct current The numerical value of voltmeter 9 and light meter 1 can be changed stepwise, when continuous 20 to 30 minutes of above-mentioned three table is unchanged, it is believed that light fixture Work reaches thermal steady state, and the numerical value for now reading D.C. voltmeter 9 is U_{Heat 1}, the numerical value of light meter 1 is L_{Heat 1}, with cold conditions value Subtract each other and exactly change value Δ U₁With Δ L₁。

4 second of value；Light fixture working power is disconnected, after light fixture integrally cools and returns to 20 DEG C ± 1 DEG C of environment temperature, Repetition carries out second of measurement and obtains L again_{Heat 2}And L_{Heat 2}Value.Error is no more than 1% with first time value error, it is believed that ΔU₁=Δ U_{It is flat}, Δ L₁=Δ L_{It is flat}Otherwise, third time is measured to average.

The 5 change values read are calculated as rate of change, are compareed with the rate of change reference value drawn by light decay detection light fixture, Judge the light decay changing condition and trend of the tested light fixture of prediction.It is required that；Forward voltage rate of temperature change X_{U is put down}%≤X_Uo%, light lead to Amount temperature rate of change X_{L is put down}%≤X_Lo%.

Claims

1. a kind of LED lamp light decay fast calculates mode, including the light fixture tested by experience aging light decay, collection nature light decay is bent Reference value on the basis of forward voltage and light flux variations rate when line and different ambient operating temperatures, compare tested light fixture and be operated in The rate of change of forward voltage and luminous flux when cold conditions and thermal steady state, judge the light decay changing condition and trend of tested light fixture.

2. the light fixture that aging light decay survey inspection in thousands of hours according to the method for claim 1, is undergone by more moneys detects formulation Light decay change curve, with reference to survey and draw the light fixture work cold conditions to during thermostabilization each temperature keep off level forward voltage and luminous flux Rate of change, describe operating temperature light decay characteristic resultant curve, establish light decay rate of change and refer to value.

3. after according to the method for claim 1, measuring tested light fixture from the cold conditions of 20 DEG C of ambient operating temperatures to thermostabilization, The change value of illuminator forward voltage and luminous flux, is converted to rate of change.

4. according to the method for claim 1, the illuminator forward voltage and light flux variations rate of tested light fixture, with nature The forward voltage and light flux variations rate reference value of light decay change light fixture collection compare, and judge tested light fixture light decay change shape Condition and trend.

5. according to the method for claim 1, tested light fixture is constant-current supply driving, electrical power change value can be measured Measured instead of forward voltage, but to exclude error caused by curent change.