CN201904723U

CN201904723U - Direct current/direct current (DC/DC) converter

Info

Publication number: CN201904723U
Application number: CN2010206540458U
Authority: CN
Inventors: 宾飞飞
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-12-10
Filing date: 2010-12-10
Publication date: 2011-07-20
Anticipated expiration: 2020-12-10

Abstract

The utility model relates to the technical field of direct current transformation circuits, in particular to a direct current/direct current (DC/DC) converter, which comprises a transformer and a rectifying and filtering circuit, wherein the transformer and the rectifying and filtering circuit are sequentially connected between a low-voltage input end and a high-voltage output end, a negative electrode of the low-voltage input end is electrically connected with a negative electrode of the high-voltage output end, the primary edge of the transformer is electrically connected with a positive electrode of the low-voltage input end, the secondary edge of the transformer is electrically connected with a positive electrode of the high-voltage output end through the rectifying and filtering circuit, the first end of the secondary edge of the transformer is connected with a collecting electrode of a first triode, the second send of the secondary edge of the transformer is connected with a collecting electrode of a second triode, emitting electrodes of the first triode and the second triode are electrically connected with the negative electrode of the low-voltage input end. The DC/DC converter has a simple structure and higher power, is simple to control and has a frequency doubling effect, i.e. the output frequency is twice of the work frequency of a single tube, value ranges of filter inductors and capacitors can be greatly reduced, the utilization rate of a magnetic core is high, and the DC/DC converter is very suitable for being applied to low-voltage heavy-current non-isolation circuits requiring twice voltage boosting.

Description

The DC/DC converter

Technical field

The utility model relates to direct current transformation circuit engineering field, is specifically related to a kind of DC/DC converter.

Background technology

The DC/DC conversion is widely used in aspects such as generation of electricity by new energy, electronic equipment power source power supply as a pith of electric and electronic technical field.Under the requirement of high-power conversion, when especially low voltage transition is high-tension application because the power electric current of power switch pipe is higher in the existing DC/DC converter, to device select, stability brings influence.And existing push-pull converter still can not be avoided above-mentioned influence fully, and simultaneously, push-pull converter circuit and control thereof are comparatively complicated, and cost is higher.

The utility model content

In view of this, in order to address the above problem, the utility model discloses a kind of structure, the simple DC/DC converter of control.

The purpose of this utility model is achieved in that the DC/DC converter, comprise the transformer T1 and the current rectifying and wave filtering circuit that are connected in successively between low pressure input and the high-voltage output end, the negative pole of described low pressure input is connected with the negative electricity of high-voltage output end, the former limit of described transformer T1 is electrically connected with the low pressure input anode, the secondary of transformer T1 is connected with the high-voltage output end positive electrical by current rectifying and wave filtering circuit, first end of transformer T1 secondary is connected with the collector electrode of triode I Q1, second end of transformer T1 secondary is connected with the collector electrode of triode II Q2, and described triode I Q1 is connected with the negative electricity of low pressure input with the emitter of triode II Q2.

Described current rectifying and wave filtering circuit comprises rectifier diode I D1, rectifier diode II D2, filter inductance L1, filter capacitor C1 and resistance R 1, the positive pole of described rectifier diode I D1 is electrically connected with first end of transformer T1 secondary, the positive pole of rectifier diode II D2 is electrically connected with second end of transformer T1 secondary, the negative pole of rectifier diode I D1 and rectifier diode IID2 is electrically connected with the end of filter inductance L1, the other end of filter inductance L1 is connected with the positive electrical of high-voltage output end, and is connected with the negative electricity of high-voltage output end with resistance R 1 by filter capacitor C1 in parallel.

DC/DC transformer configuration of the present utility model, control are simply, compare with existing BOOST converter, more powerful, and has frequency-doubled effect, be that output frequency is the twice of single tube operating frequency, can reduce the value amount of filter inductance, electric capacity greatly, magnetic core utilance height is fit to be applied in the non-isolation of low-voltage and high-current and two times of circuit that boost of need very much.

Description of drawings

Fig. 1 shows the structural representation of the utility model DC/DC converter;

Fig. 2 shows the working waveform figure of each point in the utility model DC/DC converter;

Fig. 3 shows the ripple voltage schematic diagram of the utility model DC/DC converter.

Embodiment

In order to make the purpose of this utility model, technical scheme and advantage clearer, the utility model is described in further detail below in conjunction with accompanying drawing:

Referring to Fig. 1, the DC/DC converter of present embodiment, comprise the transformer T1 and the current rectifying and wave filtering circuit that are connected in successively between low pressure input U1 and the high-voltage output end U0, the negative pole of described low pressure input is connected with the negative electricity of high-voltage output end, the former limit of described transformer T1 is electrically connected with the low pressure input anode, the secondary of transformer T1 is connected with the high-voltage output end positive electrical by current rectifying and wave filtering circuit, first end of transformer T1 secondary is connected with the collector electrode of triode I Q1, second end of transformer T1 secondary is connected with the collector electrode of triode II Q2, and described triode I Q1 is connected with the negative electricity of low pressure input with the emitter of triode II Q2.

Described current rectifying and wave filtering circuit comprises rectifier diode I D1, rectifier diode IID2, filter inductance L1, filter capacitor C1 and resistance R 1, the positive pole of described rectifier diode I D1 is electrically connected with first end of transformer T1 secondary, the positive pole of rectifier diode II D2 is electrically connected with second end of transformer T1 secondary, the negative pole of rectifier diode I D1 and rectifier diode II D2 is electrically connected with the end of filter inductance L1, the other end of filter inductance L1 is connected with the positive electrical of high-voltage output end, and is connected with the negative electricity of high-voltage output end with resistance R 1 by filter capacitor C1 in parallel.

Transformer T1 both can regard that inductance can be two-way magnetized during because of its magnetic core work as being transformer also as, so magnetic core utilance and full-bridge, half-bridge are suitable.

The DC/DC converter course of work of present embodiment can be divided into three phases:

Phase I, when Q1 conducting Q2 ends (two pipe alternate conduction), the B point is the position at zero point, and the A point is because of inducing high potential with inscription end relation, the polarity of this high potential is that a right positive left side is negative, and with the crest voltage of the superimposed generation of input voltage U1 2U1, waveform is seen shown in Figure 2, the crest voltage of 2U1 gives inductance L 1 charging by the rectification of diode D1, also gives load resistance R1 power supply simultaneously.

Second stage, when Q1Q2 all by the time, the current potential that A, B, E are 3 equates all to equal U1, this moment, inductance L 1 discharge was to keep the constant of output voltage U 0.

Phase III, when Q1 ended the Q2 conducting, its effect was similar to the phase I, does not repeat them here.

The work wave of adding Fig. 2 from these three working stages just can be readily appreciated that the mechanism of boosting of the DC/DC converter of present embodiment.Can find out obviously that from the working waveform figure of Fig. 2 the rectangular wave pulse that E is ordered is to be based upon on the higher platform voltage, and the magnitude of voltage of this platform voltage just equals input voltage U1.The amplitude of rectangular wave pulse should equate with platform voltage in theory, but in the practical application circuit less than, this point must be noted! It is the same that the mean value calculation of square wave is calculated with the average output voltage value of BUCK converter.With the mean value addition of DC input voitage U1 and square-wave voltage, the VD U0 after obtaining at last boosting, the mechanism of boosting of the DC/DC converter of Here it is present embodiment.

Introduced the DC/DC converter of present embodiment, existing its voltage gain, threshold inductance, ripple voltage and BUCK and BOOST converter are done one respectively compared in detail:

Compare this three quasi-converter as can be seen, the BOSST transducer gain is the highest, next of present embodiment, and BUCK is minimum, and the DC/DC converter of BUCK and present embodiment belongs to linear gain, BOOST is non-linear.As if from the load ripple voltage, the BOOST converter is irrelevant with inductance value, the DC/DC converter of BUCK and present embodiment then increases along with the minimizing of inductance L 1.In inductance, electric capacity and cycle one timing, the size of ripple voltage just depends on duty ratio D ₁What.BUCK converter and duty ratio D ₁Relation be the once linear function, promptly along with duty ratio D ₁Linear rising of minimizing output ripple voltage.The BOOST converter in contrast, its ripple voltage is along with duty ratio D ₁Increase and increase, but also be a kind of linear relationship.And the ripple voltage of the DC/DC converter of present embodiment is just somewhat special, its particularity is embodied on the mathematic(al) representation of ripple voltage, and its expression formula is the One-place 2-th Order function, and the figure of quadratic function is a curve, compared a great difference with linear function, referring to Fig. 3.

Claims

1.DC/DC converter, it is characterized in that: comprise the transformer (T1) and the current rectifying and wave filtering circuit that are connected in successively between low pressure input and the high-voltage output end, the negative pole of described low pressure input is connected with the negative electricity of high-voltage output end, the former limit of described transformer (T1) is electrically connected with the low pressure input anode, the secondary of transformer (T1) is connected with the high-voltage output end positive electrical by current rectifying and wave filtering circuit, first end of transformer (T1) secondary is connected with the collector electrode of triode I (Q1), second end of transformer (T1) secondary is connected with the collector electrode of triode II (Q2), and described triode I (Q1) is connected with the negative electricity of low pressure input with the emitter of triode II (Q2).

2. DC/DC converter as claimed in claim 1, it is characterized in that: described current rectifying and wave filtering circuit comprises rectifier diode I (D1), rectifier diode II (D2), filter inductance (L1), filter capacitor (C1) and resistance (R1), the positive pole of described rectifier diode I (D1) is electrically connected with first end of transformer (T1) secondary, the positive pole of rectifier diode II (D2) is electrically connected with second end of transformer (T1) secondary, the negative pole of rectifier diode I (D1) and rectifier diode II (D2) is electrically connected with an end of filter inductance (L1), the other end of filter inductance (L1) is connected with the positive electrical of high-voltage output end, and is connected with the negative electricity of high-voltage output end with resistance (R1) by filter capacitor (C1) in parallel.