CN2222412Y

CN2222412Y - Current transformer

Info

Publication number: CN2222412Y
Application number: CN 94210326
Authority: CN
Inventors: 许天昀
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-04-24
Filing date: 1994-04-24
Publication date: 1996-03-13
Anticipated expiration: 2004-04-24

Abstract

The utility model relates to a current transformer belonging to the technical field of current transformation for a semiconductor. The current transformer mainly solves the problems of the power factor and the harmonic wave of input current of a resonance current transformation device. The current transformer is mainly used for a switching power supply, or a fluorescent lamp, or an electronic ballast for a gas charging lamp. The current transformer is mainly composed of a series current transformation switch 26, an LRC resonating circuit 27, a push-and-pull rectifying circuit 18 and a filter circuit 25.

Description

A kind of convertor assembly

A kind of convertor assembly, belong to the Semiconductor Converting Technology field, mainly solve the power factor and the Harmonics of Input problem of resonance convertor assembly, it mainly is made up of series connection unsteady flow switch 26, LRC resonant circuit 27, push-and-pull rectification circuit 18, filter circuit 25, can be applicable to the voltage changer, interchange-DC voltage converter of Switching Power Supply, high-frequency induction heating, High Power Factor rectification filtering power, ups power, supersonic generator, fluorescent lamp or electronic amperite of gas-discharge lamp, interchange-a-c cycle converter, interchange-interchange etc.

Existing method one class that improves power factor and reduction current harmonics is an active power filtering, also just like patent 921008015, they are subjected to the restriction of price to many application, for improving cost performance, present technique proposes a kind of new simple and easy and practical method, it is to utilize above-mentioned many application convertor assemblys can make resonance or nearly resonance unsteady flow characteristics, supervenes the push-and-pull rectifying effect and reach and improve power factor and reduce Harmonics of Input in the unsteady flow process.

Below in conjunction with accompanying drawing present technique is done principle, structure explanation.

Fig. 1 is push-and-pull rectification, filtering, the unsteady flow schematic diagram of convertor assembly.

Fig. 2, Fig. 3, Fig. 4, Fig. 5 are the illustrations in addition of Fig. 1 push-and-pull rectification circuit.

Fig. 6 is push-and-pull rectifying and wave-filtering and the unsteady flow schematic diagram of Ying Yu in 100-130V power supply.

Fig. 7 is the illustration in addition of Fig. 6.

In Fig. 1,

diode

11,12,13,14 is formed the full-bridge type rectifier structure, its two dc output ends are C and D point, two ac input ends are A and B point, connect AC power, at the indirect filter capacitor 15 of A, B point, and at 11,12,13,14 two ends respectively and connect electric capacity 161,16,171,17 and constitute the push-and-pull rectification circuits.Electric capacity 161,16,171,17 is resonant capacitance, there is higher resonance potential at its two ends of unsteady flow process, particularly in the valley district of power supply, like this, external power voltage is connected with it and is continued simultaneously the charging of energy storage filter capacitor, thereby has improved power factor and improved Harmonics of Input.Also can just connect

electric capacity

16,17 or 16,161 or 171,17 or 16,171 respectively and constitute the push-and-pull rectification circuit, shown in Fig. 2,3,4,5 at 12,14 or 12,11 or 13,14 or 12,13 two ends.Can also only connect electric capacity 161,171 or 161,17 respectively and constitute the push-and-pull rectification circuit at 11,13 or 11,14 two ends.When the rectifier diode junction capacitance is suitable, also can remove external capacitor from, utilize they junction capacitance you be the path of resonance current, constitute the push-and-pull rectification circuit.Above-mentioned mainly is architectural feature in rectifying part, the necessary structure that constitutes total push-and-pull rectifying and wave-filtering also comprises: connect series connection unsteady flow switch 26 and filter circuit 25 between C, D point simultaneously, and the serial connection point E 26 connects driving transformer primary coil 22 to the G point, at G, B or the indirect LRC resonant circuit 27 of G, A point.Above-mentioned series connection stream switch 26 is to be in series by

thyristor

23 and 24, and series connection point is E, and 23 electric current flows into termination C point, and 24 electric current flows out termination D point; Filter circuit 25 can be single electric capacity or a plurality of electric capacity parallel connection, or a plurality of capacitances in series or the filtering net of forming by inductance and electric capacity or by current follow-up circuit (as Fig. 7 29 shown in, be that one-level is pursued stream) form; Connect unsteady flow switch drive transformer 22 at the G point, connect with the LRC resonant circuit again and receive B or A point.This example of LRC resonant circuit is the series resonance method, and its resonant inductance L is 21, and load R is 20, and resonant capacitance C is 19, and the main resonance electric capacity when being the power supply peak region during simple applications, can be removed from.Load 20 can be a resistive load, also can be the fluorescent tube of negative resistance load such as fluorescent lamp or gaseous discharge lamp and the accessory circuit in preheat curent loop (also can claim the fluorescent tube biasing circuit) thereof, can be inductive load also, as load coil, also can be the primary coil of load output transformer.

The unsteady flow of above-mentioned entire infrastructure and push-and-pull rectifying and wave-filtering principle are as follows:

In the power supply peak region, when 24 conductings, 23 by the time, resonance current from B o'clock through 19,20,21,22,24 to D points, arrive the A point through 13, finish 1/2 rectilinear oscillation; End when 24, during 23 conductings, resonance current from A o'clock through 11,23,22,21,20,19 to B points, finish 1/2 rectilinear oscillation.So in power supply source valley district because 25 energy storage makes the voltage ratio input power supply height between C, D, at this moment, establish 23 conductings, 24 end, then resonance current be from C o'clock through 23,22,21,20,19,17 (also can minute flow through 171), arrive the D point.Otherwise electric current be from C o'clock through 16 (also can minute flow through 161), B point, 19,20,21,22,24 to D points.Have higher resonance potential connect with the input power supply so on 16,17 and can continue to charge to 25 storage capacitor, so finished unsteady flow and push-and-pull rectification in one, the realization High Power Factor hangs down harmonic wave.Morphotropism is implemented also can to feed back to the part energy on 19 power supply and is further improved harmonic wave, when 25 use current follow-up circuit, also can and connect electric capacity with the further harmonic wave that improves on the discharge isolating diode in addition.

What Fig. 6 was different with Fig. 1 is that ripple filter circuit 25 is by capacitor C ₁With capacitor C ₂Be in series, their series connection point F connects an inductance or filter network 28 arrives A point or B point, so just can constitute the full-bridge voltage multiplying rectifier to be suitable for the power supply of 100-130V.At this moment, can be only filling on a

utmost point pipe

12,14 or 11,13 and connect electric capacity whole, also can be Fig. 2,3,4,5 various situations.Distortion is used also can remove 11,13 or 12,14, at this moment just aforesaid full-bridge voltage multiplying rectifier can be become the half-bridge voltage multiplying rectifier.Other principle of sort circuit is identical with figure, and just the characteristics of voltage multiplying rectifier have been introduced in rectification.Its morphotropism should be as shown in Figure 7 so.At this moment with Fig. 6 different situation be filter circuit 25 be to connect one-level current follow-up circuit 29 (can connect multistage certainly by stream, it has little significance), be the discharge isolating diode on and connect by two diodes 30 and 31 series circuits of forming, be can be respectively and electric capacity 32 and 33 at their two ends, can be not yet electric capacity also, so 30 with 31 be connected in series a little on application of power when connecing an inductance or filter network 28 to A point or B formation 100-130V.

The driving input circuit of accompanying

drawing

1,6,7 and start-up circuit and the concrete control loop of using do not draw, and the existing narration of its principle prior art does not belong to this paper characteristic range, no longer Ao Shu yet.

Claims

1, a kind of convertor assembly mainly is made up of series connection unsteady flow switch 26, LRC resonant circuit 27, push-and-pull rectification circuit 18, filter circuit 25, it is characterized in that:

A, diode 11,12,13,14 are connected into full-bridge rectification, its two dc output end is C point and D point, two ac input end A and B point, connect AC power, between A, B point, be connected to electric capacity 15, and at the two ends of diode 11,12,13,14 respectively and connect electric capacity 161,16,171,17 and constitute the push-and-pull rectification circuits;

B, between dc output end C, D point, connect series connection unsteady flow switch 26 and filter circuit 25 simultaneously;

C, the serial connection point E of unsteady flow switch 26 connect driving transformer just coil 22 to resonance current output G point, at G, B or the indirect LRC resonant circuit 27 of G, A point.

2, convertor assembly as claimed in claim 1 is characterized in that: just connect electric capacity 16,17 or electric capacity 161,171 or electric capacity 16,171 or electric capacity 161,17 formation push-and-pull rectification circuits respectively at the two ends of diode 12,14 or diode 11,13 or diode 12,13 or diode 11,14.

3, convertor assembly as claimed in claim 1 is characterized in that: the external capacitor not at the two ends of diode 11,12,13,14 as the resonance current path, constitutes the push-and-pull rectification circuit with its junction capacitance.

4, convertor assembly as claimed in claim 1 is characterized in that: filter circuit 25 is that in parallel or a plurality of capacitances in series of single electric capacity or a plurality of electric capacity or inductance are formed the filter circuit that constitutes with the filtering net of electric capacity composition or by current follow-up circuit.

5, convertor assembly as claimed in claim 1 is characterized in that: filter circuit 25 is one-level current follow-up circuits, and the discharge isolating diode on shunt capacitance, to improve current harmonics.

6, convertor assembly as claimed in claim 1, it is characterized in that: filter circuit 25 is one-level current follow-up circuits, and the discharge isolating diode on and a series circuit of forming by two diodes, and they two ends respectively and electric capacity, filter circuit when their serial connection point connects an inductance or filter network to A point or B point formation 100-130V application of power.

7, convertor assembly as claimed in claim 1 is characterized in that: filter circuit 25 is by two capacitances in series, and the filter circuit when their serial connection point F connects an inductance or filter network 28 to A point or B point formation 100-130V application of power.