CN203590563U

CN203590563U - Circuit for raising power factor of AC drive LEDs

Info

Publication number: CN203590563U
Application number: CN201320768324.0U
Authority: CN
Inventors: 毛庆斌; 何俊兴; 何正梁; 徐培亮
Original assignee: ZHEJIANG SINO SAPPHIRE TECHNOLOGY Co Ltd
Current assignee: ZHEJIANG SINO SAPPHIRE TECHNOLOGY Co Ltd
Priority date: 2013-11-29
Filing date: 2013-11-29
Publication date: 2014-05-07
Anticipated expiration: 2023-11-29

Abstract

A circuit for raising power factor of AC drive LEDs comprises an input end, a rectifying circuit, a control circuit. The input end is connected with the rectifying circuit which is connected with the control circuit. LED light sources are connected on the control circuit. The control circuit contains a control chip. The utility model has beneficial effects as follows: the circuit has a simple and reasonable structure, is convenient to use and has low design difficulty; the control chip of the control circuit is adopted to achieve the synchronization effect of input voltage and input current; power factor is raised; use of an electrolytic condenser is avoided; service life of the circuit is prolonged; and the circuit has good using effects and is good for popularization.

Description

A kind of circuit that exchanges driving LED power factor (PF) that improves

Technical field

The utility model relates to a kind of circuit, especially a kind of circuit that exchanges driving LED power factor (PF) that improves.

Background technology

At present, conventional AC driving LED circuit is after access civil power, rectification circuit carrys out driving LED by resistance current limliting more after filtering, this traditional mode can be an ac cycle conducting in order to meet LED, need to after rectification circuit, increase larger filter capacitor so that enough voltage driving LED to be provided, but after having increased larger filter capacitor, input current waveform has become burst pulse, it is lower that power factor (PF) becomes, and effect is poor.

Utility model content

The utility model will solve the problem that above-mentioned prior art exists, and a kind of circuit that exchanges driving LED power factor (PF) that improves is provided, simple and reasonable, easy to use, can improve and exchange driving LED power factor (PF), remove the use of electrolytic capacitor from, meet people's demand.

The utility model solves the technical scheme that its technical problem adopts: this raising exchanges the circuit of driving LED power factor (PF), comprise input, rectification circuit, control circuit, input is connected with rectification circuit, rectification circuit is connected with control circuit, on control circuit, be connected with some string LED light sources, every string LED light source comprises some LEDs light sources, rectification circuit comprises rectifier bridge, control circuit comprises control chip, is provided with for the control logic circuit in constant current state by the current stabilization of the LED light source of flowing through in control chip.After arranging like this, simple and reasonable, easy to use, during use, after input incoming transport electrical network, by rectification circuit, by the negative half-cycle waveform upset of AC sine wave, be positive half period waveform, thereby make rectification postwave shape become the half-wave of two positive half periods owing to having removed the use of filter capacitor from, when the voltage after rectification rises to the Vf value of the first string LED light source from 0V, on control circuit, the control logic circuit of control chip is lighted the first string LED light source, and by control logic circuit by current stabilization in the first constant current state, voltage after rectification continue to rise the Vf value and second that reaches the first string LED light source go here and there LED light source Vf value and time, on control circuit, the control logic circuit of control chip is lighted the first string LED light source and the second string LED light source simultaneously, and by flow through the first string LED light source and second string LED light source current stabilization in the second constant current state, repeat this process, carry out successively until all LED light sources are lit, on control circuit, the control logic circuit of control chip is lighted all LED light sources, and by the current stabilization of all LED light sources in constant current state, process in contrast to this, when trailing edge voltage drops to 0V from crest voltage, said process carries out in reverse order, complete lighting and extinguishing process of LED light source, by control chip, detect the voltage waveform of input, and the Vf voltage that contrasts every string LED light source obtains a minute crosstalk pressure, when input voltage reaches minute string magnitude of voltage, the LED light source of corresponding string is lighted, removed the use of filter capacitor from, owing to having removed the use of filter capacitor from, thereby input voltage is synchronizeed with input current, therefore obtain higher power factor (PF), owing to having removed the use of filter capacitor from, thereby removed the use of electrolytic capacitor from, therefore circuit is not subject to the electrolytic capacitor restriction in useful life, increased the useful life of circuit, result of use is good.

The quantity of LED light source is 3 string-8 strings.After arranging like this, the quantity of LED light source is in controlled range, and the quantity of LED light source can meet instructions for use.

On LED light source, be connected with lamp plate, rectification circuit, control circuit are all welded on lamp plate.After arranging like this, LED light source and rectification circuit, control circuit are all connected on lamp plate, have reduced the volume of circuit, have removed the use of outer casing of power supply from, have reduced the space that circuit takies at light fixture, and result of use is good.

The effect that the utility model is useful is: raising of the present utility model exchanges the circuit of driving LED power factor (PF), simple and reasonable, easy to use, design difficulty is low, reduced staff's design work amount, reduced the design cost of circuit, adopt the control chip of control circuit to realize input voltage and the synchronous effect of input current, improved power factor (PF), removed the use of electrolytic capacitor from, increased the useful life of circuit, and circuit can be welded on lamp plate, realize the integrated effect of circuit lamp plate, removed the use of outer casing of power supply from, reduced the space that circuit takies, result of use is good, be beneficial to popularization.

Accompanying drawing explanation

Fig. 1 is the circuit diagram of the utility model embodiment;

Fig. 2 is the block diagram of the utility model embodiment.

Description of reference numerals: input 1, rectification circuit 2, control circuit 3, LED light source 4, rectifier bridge 5, control chip 6, control logic circuit 7, lamp plate 8.

Embodiment

Below in conjunction with accompanying drawing, the utility model is described in further detail:

With reference to accompanying drawing: the raising in the present embodiment exchanges the circuit of driving LED power factor (PF), comprise input 1, rectification circuit 2, control circuit 3, input 1 is connected with rectification circuit 2, rectification circuit 2 is connected with control circuit 3, on control circuit 3, be connected with some string LED light sources 4, every string LED light source 4 comprises some LEDs light sources 4, rectification circuit 2 comprises rectifier bridge 5, control circuit 3 comprises control chip 6, is provided with for the control logic circuit 7 in constant current state by the current stabilization of the LED light source 4 of flowing through in control chip 6.

The quantity of LED light source 4 is 3 string-8 strings.

On LED light source 4, be connected with lamp plate 8, rectification circuit 2, control circuit 3 are all welded on lamp plate 8.

Control chip 6 adopts Lai Tuosi control chip 6.

In the present embodiment, every string LED light source 4 comprises 18 string LED light sources 4, and the Vf value of single-string LED light source 4 is between 2.8V-3.6V.

During use, after input 1 incoming transport electrical network, by rectification circuit 2, by the negative half-cycle waveform upset of AC sine wave, be positive half period waveform, thereby make rectification postwave shape become the half-wave of two positive half periods owing to having removed the use of filter capacitor from, when the voltage after rectification rises to the Vf value of the first string LED light source 4 from 0V, on control circuit 3, the control logic circuit 7 of control chip 6 is lighted the first string LED light source 4, and by control logic circuit 7 by current stabilization in the first constant current state, voltage after rectification continue to rise the Vf value and second that reaches the first string LED light source 4 go here and there LED light source 4 Vf value and time, on control circuit 3, the control logic circuit 7 of control chip 6 is lighted the first string LED light source 4 and the second string LED light source 4 simultaneously, and by flow through the first string LED light source 4 and second string LED light source 4 current stabilization in the second constant current state, repeat this process, carry out successively until all LED light sources 4 are lit, on control circuit 3, the control logic circuit 7 of control chip 6 is lighted all LED light sources 4, and by the current stabilization of all LED light sources 4 in constant current state, process in contrast to this, when trailing edge voltage drops to 0V from crest voltage, said process carries out in reverse order, complete lighting and extinguishing process of LED light source 4.

The feature of the present embodiment is: the voltage waveform that detects input by control chip 6, and the Vf voltage that contrasts every string LED light source 4 obtains a minute crosstalk pressure, when input voltage reaches minute string magnitude of voltage, the LED light source of corresponding string is lighted, removed the use of filter capacitor from, owing to having removed the use of filter capacitor from, thereby input voltage is synchronizeed with input current, therefore obtain higher power factor (PF), owing to having removed the use of filter capacitor from, thereby removed the use of electrolytic capacitor from, therefore circuit is not subject to the electrolytic capacitor restriction in useful life, increased the useful life of circuit, result of use is good.

Although the utility model illustrates and describes by reference to preferred embodiment,, those skilled in the art should understand, and in the scope of claims, can do the various variation in form and details.

Claims

1. one kind is improved the circuit that exchanges driving LED power factor (PF), it is characterized in that: comprise input (1), rectification circuit (2), control circuit (3), described input (1) is connected with rectification circuit (2), described rectification circuit (2) is connected with control circuit (3), on described control circuit (3), be connected with some string LED light sources (4), every string LED light source (4) comprises some LEDs light sources (4), described rectification circuit (2) comprises rectifier bridge (5), described control circuit (3) comprises control chip (6), in described control chip (6), be provided with the control logic circuit (7) in constant current state for the current stabilization of the LED light source (4) of flowing through.

2. raising according to claim 1 exchanges the circuit of driving LED power factor (PF), it is characterized in that: the quantity of described LED light source (4) is 3 string-8 strings.

3. raising according to claim 1 exchanges the circuit of driving LED power factor (PF), it is characterized in that: on described LED light source (4), be connected with lamp plate (8), described rectification circuit (2), control circuit (3) are all welded on lamp plate (8).