CN2854998Y

CN2854998Y - LED lighting circuit of preventing interference of power grid noise

Info

Publication number: CN2854998Y
Application number: CN200520036408.0U
Authority: CN
Inventors: 吕大明
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-12-02
Filing date: 2005-12-02
Publication date: 2007-01-03
Anticipated expiration: 2015-12-02

Abstract

The utility model discloses a LED lighting circuit of preventing interference of power grid noise, which includes an AC-DC rectifying circuit, a LED array and capacitance. The DC-output of the AC-DC rectifying circuit is the power supply for the LED array. The LED array includes a plurality of LED lights which connected with each other in series and/or in parallel. Moreover, a plurality of LED lights in series are parallelly connected with the capacitance. The utility model has the advantages of: the effection generated by the instantaneous peak pulsating can be effectively smoothed when the interference of power grid noise occuring, the work entironment of the parallelly connected LED lights can be ensured steadyly, the illuming effection can be optimized, and the life of the LED can be increased.

Description

Anti-electric network noise disturbs the LED lighting circuit

[technical field]

The utility model relates to the lighting circuit that adopts Alternating Current Power Supply, especially relates to a kind of anti-electric network noise and disturbs the LED lighting circuit.

[background technology]

The luminaire that generally uses at city's electric lighting field at present mainly contains incandescent lamp, fluorescent lamp etc.Incandescent lamp is because heating is big, and the energy consumption height progressively is being eliminated, and fluorescent lamp then has the life-span short, and structure is comparatively complicated, so the higher shortcoming of use cost.Advantages such as LED (Light emitting diode, light-emitting diode) is efficient, energy-conservation with it, the life-span is long more and more come into one's own in this field.

Before this, in application number is 200420060342.4 and 200420061456.0 Chinese utility application, applicant of the present invention has proposed two kinds of LED lighting circuit structures that are suitable for Alternating Current Power Supply, i.e. serial connection led array and/or constant-current source behind rectification circuit.These two circuit structures provide very simple civil power lighting solutions based on big quantity LED lamp.Under the whole more stable situation of utility grid voltage (fluctuation is less than 10%), can obtain to stablize, good actual effect.

But along with the further investigation of above-mentioned patent application in actual production and application found, instantaneous noise in the electrical network, for example meeting such as spike interference has a negative impact to the illuminating effect of above-mentioned LED lighting circuit, cause problems such as brightness flicker, also influence the life-span of LED lamp simultaneously to a certain extent.Along with the emerge in multitude of electronic equipment, computer and high-power household electrical appliance and extensively universal, electric network noise disturbs serious day by day and forms a kind of public hazards, particularly transient noise is disturbed, its rate of climb is fast, the duration is short, voltage amplitude amplitude height (several hectovolts are to several kilovolts), randomness are strong, and the illuminating product that has therefore become direct access electrical network must not one of irrespectively influence on circuit design.

[summary of the invention]

The technical problems to be solved in the utility model provides a kind of simple in structure, with low cost, long service life, can effectively prevent the LED lighting circuit that electric network noise disturbs.

In order to solve the problems of the technologies described above, the technical scheme that adopts of the present utility model is: a kind of anti-electric network noise disturbs the LED lighting circuit, comprise alternating current-direct current rectification circuit, led array and electric capacity, the direct current of described alternating current-direct current rectification circuit is output as the led array power supply, described led array comprises some LED lamps that are connected with series connection and/or parallel-connection structure each other, and several are also in parallel with electric capacity with the LED lamp that cascaded structure is connected.

Alleged in the utility model " led array " can have various series and parallel types of attachment, for example, some LED lamps be connected into that row, multiple row series connection are in parallel again, the multiple row series connection is in parallel again and row between have and laterally be connected to form fenestral fabric etc.

Preferably, described led array is made of several LED units in series and/or parallel connection, and described LED unit is made of 1～80 LED lamp series connection, every group of LED unit electric capacity in parallel.

Further preferably, described LED unit is made of 3～20 LED lamps series connection.

Above-mentioned lighting circuit also can comprise filter circuit, the direct current output-parallel filter circuit and the led array of described alternating current-direct current rectification circuit.Filter circuit can select filter capacitor to serve as.

Above-mentioned lighting circuit also can comprise constant-current source circuit, and described constant-current source circuit is connected in the current supply circuit of led array.

The rectifier bridge that described alternating current-direct current rectification circuit preferably is made up of crystal diode.

Useful technique effect of the present utility model is: 1) be several LED lamp shunt capacitances that is cascaded, the influence that effectively level and smooth instantaneous spike shake produces in the time of can producing in the interference of electric network noise, guarantee that several LED light fixtures in parallel with it have metastable operational environment, optimize illuminating effect, prolong the useful life of LED.2) the LED lamp in the led array is divided into groups, shunt capacitance can effectively reduce the requirement to capacitance respectively, reduces cost greatly.The cost of a common little electric capacity only needs several sharing money, and the electric capacity of using about 20 in the general LED illuminating product can exert an influence to the cost of entire product hardly, can produce good effect again simultaneously, therefore is economical and preferred version efficiently.

The utility model is described in further detail below in conjunction with the drawings and specific embodiments:

[description of drawings]

Fig. 1 is that a kind of anti-electric network noise disturbs LED lighting circuit schematic diagram.

Fig. 2 is that another kind of anti-electric network noise disturbs LED lighting circuit schematic diagram.

Fig. 3 is that another anti-electric network noise disturbs LED lighting circuit schematic diagram.

[embodiment]

Embodiment one, a kind of anti-electric network noise disturb the LED lighting circuit, and as shown in Figure 1,4 LED lamps series connection constitute a LED unit, after several such LED units in series again multiple row compose in parallel led array, each LED unit capacitor C in parallel.Above-mentioned led array is connected between the dc output end of rectification circuit Q.The rectifier bridge that rectification circuit Q is made up of four crystal diodes, its non-conterminous a pair of tie point is an input, connects the two ends of AC power AC respectively, another is a dc output end to tie point.

Embodiment two, another kind of anti-electric network noise disturb the LED lighting circuit, as shown in Figure 2, its structure and embodiment one are basic identical, just also be parallel with the filter capacitor Cs as the AC coupled element between the dc output end of rectification circuit Q, this electric capacity plays the effect of the output waveform of improving rectification circuit Q.

Embodiment three, another anti-electric network noise disturb the LED lighting circuit, and as shown in Figure 3, its structure and embodiment two are basic identical, just also are in series with constant-current source in the current supply circuit of led array.Constant-current source in this example adopts such structure: a triode T as drive current adjustment pipe, and its current collection is the constant current output very, connects led array; Connect with emitter behind voltage stabilizing didoe D of its base stage series connection, parallel connection connects the output that rectification circuit Q is not connected with led array as the external power supply end behind the current limliting feedback resistance Re; As the base bias voltage input, be connected between any two adjacent light-emitting diodes of any row in the led array behind base biasing resistor Rb of its base stage series connection.

Adopted constant-current source circuit in this example, can reduce requirement, can guarantee the relative stability of LED operating current in the relatively poor area of power supply situation, made LED that be arranged longer useful life power source integral stability.Voltage stabilizing didoe in this example can replace with two mutual diode in series.In addition, in actual applications, can also use the circuit of variable voltage to replace voltage stabilizing didoe or provide reference voltage, realize the variable chemical control system of LED luminosity with this with the series diode of voltage stabilizing didoe same function.

Among above-mentioned each embodiment, the number of series LED is in theory also unrestricted in the LED unit, considers problems such as circuit connection, shunt capacitance selection, and the series connection number is relatively more suitable between 3～20.The capacitance in parallel with the LED unit can be chosen as required within the specific limits, and its capacity is relevant with the power factor of entire circuit: capacity is big more, and condensance is big more.So will select: 1. can satisfy substantially and stabilize the electrical network flickering, improve the requirement of illuminating effect according to two principles; The power factor that 2. can make complete machine is wanted to reach designing requirement than higher at least.Also extremely important as for minimizing cost, but preceding two requirements should be at first satisfied.According to practical experience, the capacity of shunt capacitor 22 μ f～470 μ f can, scope enlarges that some are good again.The size of capacity only influences the smooth performance of operating current, can characterize with ' ripple coefficient ', and the bigger ripple characteristics of capacity are better in general.But in actual use, electric capacity strengthens and also can bring such as a series of new problems such as the stability of a system, reliabilities, the most direct cost problem in addition.So in conjunction with the characteristics that conventional illumination needs, selected capacitance mainly concentrates on 22 μ f～220 μ f, and be many with 22 μ f.

The utility model is exchanging illumination with its simple structure, cheap cost and good actual effect Engineering, road lighting, lighting of home, architectural lighting, decorative lighting, the dance of particularly being powered by utility grid The aspects such as desk lamp light have a wide range of applications, compare with existing electrical network lighting solutions have very aobvious The advantage of work.

Claims

1, a kind of anti-electric network noise disturbs the LED lighting circuit, comprise alternating current-direct current rectification circuit and led array, the direct current of described alternating current-direct current rectification circuit is output as the led array power supply, described led array comprises some LED lamps that are connected with series connection and/or parallel-connection structure each other, it is characterized in that: also comprise electric capacity, several are also in parallel with electric capacity with the LED lamp that cascaded structure is connected in the described led array.

2, anti-electric network noise according to claim 1 disturbs the LED lighting circuit, it is characterized in that: described led array is made of several LED units in series and/or parallel connection, described LED unit is made of 1～80 LED lamp series connection, every group of LED unit electric capacity in parallel.

3, anti-electric network noise according to claim 2 disturbs the LED lighting circuit, it is characterized in that: described LED unit is made of 3～20 LED lamp series connection.

4, disturb the LED lighting circuit according to any described anti-electric network noise of claim 1～3, it is characterized in that: also comprise filter circuit, the direct current output-parallel filter circuit and the led array of described alternating current-direct current rectification circuit.

5, disturb the LED lighting circuit according to any described anti-electric network noise of claim 1～3, it is characterized in that: also comprise constant-current source circuit, described constant-current source circuit is connected in the current supply circuit of led array.

6, disturb the LED lighting circuit according to any described anti-electric network noise of claim 1～3, it is characterized in that: described alternating current-direct current rectification circuit is the bridge rectifier that is constituted by a diode.