CN201611846U

CN201611846U - Electronic transformer

Info

Publication number: CN201611846U
Application number: CN2009202156466U
Authority: CN
Inventors: 黄力; 侯永峰
Original assignee: Ningbo Zhongce Et Electronics Co Ltd
Current assignee: Ningbo Zhongce Et Electronics Co Ltd
Priority date: 2009-12-30
Filing date: 2009-12-30
Publication date: 2010-10-20
Anticipated expiration: 2019-12-30

Abstract

The utility model discloses an electronic transformer which comprises a rectifying circuit (1), a start-up circuit (2), an oscillating circuit (3) and an output transformer (4), wherein the rectifying circuit (1) is connected with the start-up circuit (2) which is connected with the oscillating circuit (3); the oscillating circuit (3) is connected with the output transformer (4); the start-up circuit (2) comprises a start-up resistor R2 and an electromagnetic interference suppression circuit, wherein the electromagnetic interference suppression circuit (5) comprises an L-shaped low-pass filter (5.1), an LC filter (5.2) and a filtering capacitor (5.3); the L-shaped low-pass filter (5.1) is connected with the input end of the rectifying circuit (1); the LC filter (5.2) is connected between the rectifying circuit (1) and the start-up circuit (2); and the filtering capacitor (5.3) is connected with the output end of the output transformer (4). The electronic transformer can effectively filter the high-frequency clutters in the circuit, and suppresses the electromagnetic radiation.

Description

Electronic transformer

Technical field

The utility model relates to a kind of electronic transformer.

Background technology

Electronic transformer comprises rectification circuit, start-up circuit, oscillating circuit and output transformer, described rectification circuit is connected with described start-up circuit, described start-up circuit is connected with described oscillating circuit, and described oscillating circuit is connected with described output transformer.Described rectification circuit becomes Rectified alternating current to alternating current, again pulsating direct current is become high-frequency current by oscillating circuit, then by the output voltage device to the hf and hv pulse step-down, obtain required output voltage and power.But owing to have a large amount of high frequency clutters in the work electrical network, during electronic transformer work, these clutters can produce certain influence to the operate as normal of follow-up circuit, thereby cause the job stability and the reliability decrease of electronic transformer; Again because alternating current exports after rectification is pulsating direct current, and oscillating circuit becomes pulsating direct current into the high frequency alternating current, this process can produce very big electromagnetic radiation, and other electronic products are disturbed in a large amount of electromagnetic radiation meetings, also can work the mischief and influences the healthy of people human body.

The utility model content

The technical problems to be solved in the utility model is that high frequency clutter and the electronic transformer that suppresses electromagnetic radiation in a kind of effectively elimination circuit are provided.

Technical solution of the present utility model is, a kind of electronic transformer with following structure is provided, it comprises rectification circuit, start-up circuit, oscillating circuit and output transformer, described rectification circuit is connected with described start-up circuit, described start-up circuit is connected with described oscillating circuit, described oscillating circuit is connected with described output transformer, described start-up circuit comprises starting resistance R2, it also comprises electromagnetic interference suppression circuit, described electromagnetic interference suppression circuit comprises L type low pass filter, LC filter and filter capacitor, described L type low pass filter is connected the input of described rectification circuit, described LC filter is connected between described rectification circuit and the start-up circuit, and described filter capacitor is connected the output of described output transformer.

After adopting above structure, the utility model electronic transformer compared with prior art has the following advantages:

Because the utility model electronic transformer connects L type low pass filter at the input of rectification circuit, L type low pass filter can elimination high frequency clutter in the electric current of input, the waveform of the voltage of feasible input has clear improvement, thereby can guarantee the operate as normal of follow-up circuit, also improve the stability and the reliability of the work of electronic transformer, can also suppress electromagnetic interference simultaneously; Owing to is connected the LC filter between described rectification circuit and start-up circuit, the frequency of oscillation of LC filter is suitable with the operating frequency of oscillating circuit, makes circuit working in resonance condition again, the radiation of minimizing electromagnetic wave outside; Also owing to the output at described output transformer connects filter capacitor, the pulsating direct current that filter capacitor can suppress after the rectification becomes a large amount of electromagnetic radiation that produces in the process of high frequency alternating current through behind the oscillating circuit, thereby realization electromagnetic compatibility, its effect can make electronic transformer not disturb for other electronic products, to not injury of human body, can also resist extraneous electromagnetic interference.

As a kind of improvement of the present utility model, described L type low pass filter comprises inductance I and electric capacity, described L type low pass filter comprises inductance L 1 and capacitor C 4, described inductance L 1 is connected on the input of described rectification circuit, one end of described capacitor C 4 is connected between described inductance L 1 and the rectification circuit, and the other end of described capacitor C 4 is connected on another input of described rectification circuit.Described LC filter comprises inductance L 2 and capacitor C 5, and described inductance L 2 is connected the output of described rectification circuit, and described capacitor C 5 is connected in parallel on the starting resistance R2 of described start-up circuit.One end of described filter capacitor is connected with the output of described output transformer, the other end ground connection of described filter capacitor.

Description of drawings

Fig. 1 is the circuit theory diagrams of the electronic transformer of prior art.

Fig. 2 is the circuit theory diagrams of the utility model electronic transformer.

Shown in the figure: 1, rectification circuit, 2, start-up circuit, 3, oscillating circuit, 4, output transformer, 5, electromagnetic interference suppression circuit (EMI suppresses circuit), 5.1, L type low pass filter, 5.2, the LC filter, 5.3, filter capacitor.

Embodiment

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

See also shown in Figure 1, the electronic transformer of prior art comprises rectification circuit 1, start-up circuit 2, oscillating circuit 3 and output transformer 4, described rectification circuit 1 is connected with described start-up circuit 2, described start-up circuit 2 is connected with described oscillating circuit 3, and described oscillating circuit 3 is connected with described output transformer 4.Described rectification circuit 1 is the rectifier bridge that is made of diode VD1-VD4, and the alternating current of input is become Rectified alternating current.Described start-up circuit 2 comprises starting resistance R2, starts capacitor C 1, avalanche diode D1 and diode D2, is used to start electronic transformer.Described oscillating circuit 3 comprises oscillation transformer T1, triode Q1 and triode Q2, and described oscillation transformer T1 comprises elementary winding T1c and two secondary winding T1a and T1b, and this oscillating circuit 3 is used for pulsating direct current is become high-frequency current.Described output voltage device 4 is used for step-down is carried out in the high frequency voltage pulse, obtains required output voltage and power.

See also shown in Figure 2ly, electronic transformer of the present utility model comprises also that on the basis of existing technology EMI suppresses circuit 5.Described EMI suppresses circuit 5 and comprises L type low pass filter 5.1, LC filter 5.2 and filter capacitor 5.3.Described L type low pass filter 5.1 comprises inductance L 1 and capacitor C 4, described inductance L 1 is connected on the input of described rectification circuit 1, one end of described capacitor C 4 is connected between described inductance L 1 and the rectification circuit 1, the other end of described capacitor C 4 is connected on another input of described rectification circuit 1, and described L type low pass filter 5.1 is used for the high frequency clutter of the electric current of elimination input.Described LC filter 5.2 comprises inductance L 2 and capacitor C 5, described inductance L 2 is connected the output of described rectification circuit 1, described capacitor C 5 is connected in parallel on the starting resistance R2 of described start-up circuit 2, the operating frequency of the frequency of oscillation of described LC filter 5.2 and oscillating circuit 3 is suitable, make circuit working in resonance condition, reduce the electromagnetic wave outside radiation; One end of described filter capacitor 5.3 is connected with the output of described output transformer 4, the other end ground connection of described filter capacitor 5.3, described filter capacitor 5.3 are used for suppressing a large amount of electromagnetic radiation that the pulsating direct current after the rectification produces through the process that becomes the high frequency alternating current behind the oscillating circuit 3.

Claims

1. electronic transformer, it comprises rectification circuit (1), start-up circuit (2), oscillating circuit (3) and output transformer (4), described rectification circuit (1) is connected with described start-up circuit (2), described start-up circuit (2) is connected with described oscillating circuit (3), described oscillating circuit (3) is connected with described output transformer (4), described start-up circuit (2) comprises starting resistance R2, it is characterized in that: it also comprises electromagnetic interference suppression circuit (5), described electromagnetic interference suppression circuit (5) comprises L type low pass filter (5.1), LC filter (5.2) and filter capacitor (5.3), described L type low pass filter (5.1) is connected the input of described rectification circuit (1), described LC filter (5.2) is connected between described rectification circuit (1) and the start-up circuit (2), and described filter capacitor (5.3) is connected the output of described output transformer (4).

2. electronic transformer according to claim 1, it is characterized in that: described L type low pass filter (5.1) comprises inductance L 1 and capacitor C 4, described inductance L 1 is connected on the input of described rectification circuit (1), one end of described capacitor C 4 is connected between described inductance L 1 and the rectification circuit (1), and the other end of described capacitor C 4 is connected on another input of described rectification circuit (1).

3. electronic transformer according to claim 1, it is characterized in that: described LC filter (5.2) comprises inductance L 2 and capacitor C 5, described inductance L 2 is connected the output of described rectification circuit (1), and described capacitor C 5 is connected in parallel on the starting resistance R2 of described start-up circuit (2).

4. electronic transformer according to claim 1 is characterized in that: an end of described filter capacitor (5.3) is connected with the output of described output transformer (4), the other end ground connection of described filter capacitor (5.3).