CN2706955Y

CN2706955Y - Boost type active staggered parallel soft switch DC-DC converter

Info

Publication number: CN2706955Y
Application number: CN 200420037469
Authority: CN
Inventors: 何湘宁; 姚刚
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2004-07-08
Filing date: 2004-07-08
Publication date: 2005-06-29
Anticipated expiration: 2014-07-08

Abstract

The utility model discloses a boost type active staggered parallel soft switch DC-DC converter comprising two coupled inductance, two follow current diodes and two power switch tubes. The drain of a first power switch tube is connected with the anode of a second diode and one end of a second inductance, the drain of a second power switch tube is connected with the anode of a first diode and one end of a first inductance, the other end of the first inductance is connected with the other end of the second inductance, the first power switch tube is connected in parallel with a series circuit composed of the first capacitor and a first auxiliary switch tube, and the second power switch tube is connected in parallel with a series circuit composed of the second capacitor and a second auxiliary switch tube. The utility model has few attached devices, simple structure, no additional detection and no energy loss element in circuit, the efficiency of boost type active staggered parallel circuit can be increased, and no-voltage overshoots when then power switch tubes are cut off in the process of inversion.

Description

The soft switch dc-dc converter of the active crisscross parallel of booster type

Technical field

The utility model relates to DC-DC converter.Be the soft switch dc-dc converter of the active crisscross parallel of booster type specifically.

Background technology

Conventional booster type (Boost) crisscross parallel DC-DC converter, comprise two inductance L 1, L2, two sustained diode 1, D2, two power switch tube S 1, S2, the drain electrode of first power switch tube S 1 links to each other with the anode of the second diode D2 and an end of second inductance L 2, the drain electrode of second power switch tube S 2 links to each other with the anode of the first diode D1 and an end of first inductance L 1, and the other end of first inductance L 1 links to each other with the other end of second inductance L 2.This boost interleaved parallel DC-DC converter is generally hard switching work, and switching loss is bigger.In recent years, studied some soft switch circuits in succession, mainly contained two kinds: a kind of is additional active and passive component in converter, realizes the soft switch of power device; Another kind is the additional passive buffer circuit that contains resistance, and its energy loss is big, and energy consumption causes the circuit working decrease in efficiency during work on resistance.

Summary of the invention

It is few that the purpose of this utility model provides add ons quantity, simple in structure, and cost is low, and the soft switch dc-dc converter of the active crisscross parallel of the booster type of noenergy loss.

Technical solution of the present utility model is, the soft switch dc-dc converter of the active crisscross parallel of booster type comprises two inductance that are coupled, two fly-wheel diodes, two power switch pipes, the drain electrode of first power switch pipe links to each other with the anode of second diode and an end of second inductance, the drain electrode of second power switch pipe links to each other with the anode of first diode and an end of first inductance, the other end of first inductance links to each other with the other end of second inductance, it is characterized in that the series circuit that constitutes by first electric capacity and first auxiliary switch in the first power switch pipe parallel connection, wherein first auxiliary switch is consistent with the first power switch pipe direction, and first electric capacity links to each other with the contact of first power switch pipe with second inductance; At the series circuit that the second power switch pipe parallel connection is made of second electric capacity and second auxiliary switch, wherein second auxiliary switch is consistent with the second power switch pipe direction, and second electric capacity links to each other with the contact of second power switch pipe with first inductance.

During work, utilize the leakage inductance of two coupling inductances to realize the soft shutoff of zero current turning-on and first, second two fly-wheel diodes of first power switch pipe, second power switch pipe; When first power switch pipe and second power switch pipe turn-off, because the existence of first electric capacity and second electric capacity has realized that the no-voltage of first power switch pipe and second power switch pipe is turn-offed.Simultaneously, first, second two electric capacity of each switch periods are collected these energy, and it transfers to load the most at last, have realized absorbing the harmless operation of circuit.In whole switch periods,, first, second two auxiliary switches realization no-voltages are opened with no-voltage turn-offed by controlling the gate pulse of first, second auxiliary switch.

The soft switch dc-dc converter of the active crisscross parallel of booster type of the present utility model has utilized the leakage inductance of coupling inductance to realize the soft switch of power switch pipe, need not the outer inductance element of plus, thereby add ons is few, and is simple in structure, and cost is low, need not extra testing circuit, noenergy losser in the circuit can improve the efficient of boost interleaved parallel circuit, and in the commutation course, no-voltage overshoot when power switch pipe turn-offs, no current overshoot when fly-wheel diode is opened.

Description of drawings

Fig. 1 is the circuit diagram of the soft switch dc-dc converter of the active crisscross parallel of booster type.

Embodiment

Referring to Fig. 1, the soft switch dc-dc converter of the active crisscross parallel of booster type comprises two inductance L that are coupled 1, L2, two sustained diode 1, D2, two power switch tube S 1, S2, the drain electrode of first power switch tube S 1 links to each other with the anode of the second diode D2 and an end of second inductance L 2, the drain electrode of second power switch tube S 2 links to each other with the anode of the first diode D1 and an end of first inductance L 1, the other end of first inductance L 1 links to each other with the other end of second inductance L 2, it is characterized in that the series circuit that constitutes by first capacitor C 1 and the first auxiliary switch S3 in 1 parallel connection of first power switch tube S, wherein the first auxiliary switch S3 is consistent with first power switch tube S, 1 direction, and first capacitor C 1 links to each other with the contact of first power switch tube S 1 and second inductance L 2; The series circuit that constitutes by second capacitor C 2 and the second auxiliary switch S4 in 2 parallel connections of second power switch tube S, wherein the second auxiliary switch S4 is consistent with second power switch tube S, 2 directions, and second capacitor C 2 links to each other with the contact of second power switch tube S 2 and first inductance L 1.

The soft switch dc-dc converter of the active crisscross parallel of booster type exists four kinds of change of current situations, the i.e. change of current between the change of current between first power switch tube S 1 and first sustained diode 1 and first power switch tube S 1 and second sustained diode 2; The change of current between the change of current between second power switch tube S 2 and second sustained diode 2 and second power switch tube S 2 and first sustained diode 1.Because the symmetry of circuit structure, only the commutation course with first power switch tube S 1 is that example is analyzed as follows:

First power switch tube S 1 is open-minded, the commutation course that first sustained diode 1 is turn-offed:

Before the change of current, circuit is in the steady-working state of 1 shutoff of first power switch tube S, 1 afterflow of first sustained diode.When first power switch tube S 1 is opened, because the leakage inductance of coupling inductance L1, L2 exists, the electric current of first power switch tube S 1 is started from scratch and is risen so that certain slope is linear, promptly first power switch tube S 1 has realized zero current turning-on, the current value of first sustained diode 1 begins to reduce with identical slope linearity from input current simultaneously, turn-offs until first sustained diode 1.Like this, the reverse recovery current of first sustained diode 1 is zero, has reduced the reverse recovery loss that first sustained diode 1 is brought greatly.First sustained diode 1 is closed and is had no progeny, and second capacitor C 2 diode in the body of the second auxiliary switch S4 begins the leakage inductance resonance with coupling inductance L1, L2, and the voltage on second capacitor C 2 reduces to zero.Afterwards, circuit enters the steady operational status of first power switch tube S, 1 conducting.

First power switch tube S 1 is turn-offed the commutation course that second sustained diode 2 is opened:

Before first power switch tube S 1 is turn-offed, the first auxiliary switch S3 conducting, because before the first auxiliary switch S3 conducting, first power switch tube S 1 conducting, such first auxiliary switch S3 has realized that no-voltage is open-minded.First power switch tube S 1 is closed and is had no progeny, and to 1 charging of first capacitor C, the tube voltage of first power switch tube S 1 has realized promptly that from liter above freezing the no-voltage of first power switch tube S 1 is turn-offed to input current through the first auxiliary switch S3.When first capacitor C, 1 voltage charging extremely equates with last output capacitance terminal voltage, the 2 natural conductings of second sustained diode.First power switch tube S 1 is closed to have no progeny and the first auxiliary switch S3 is turn-offed again, because first capacitor C, 1 both end voltage is an output voltage, the first auxiliary switch S3 has realized the no-voltage shutoff.Circuit enters the stable state of load current by 2 outputs of second sustained diode.

Claims

1. the soft switch dc-dc converter of the active crisscross parallel of booster type comprises two inductance (L1 that are coupled, L2), two fly-wheel diode (D1, D2), two power switch pipe (S1, S2), the drain electrode of first power switch pipe (S1) links to each other with the anode of second diode (D2) and an end of second inductance (L2), the drain electrode of second power switch pipe (S2) links to each other with the anode of first diode (D1) and an end of first inductance (L1), the other end of first inductance (L1) links to each other with the other end of second inductance (L2), it is characterized in that at first power switch pipe (S1) series circuit that constitutes by first electric capacity (C1) and first auxiliary switch (S3) in parallel, wherein first auxiliary switch (S3) is consistent with first power switch pipe (S1) direction, and first electric capacity (C1) links to each other with the contact of first power switch pipe (S1) with second inductance (L2); At second power switch pipe (S2) series circuit that constitutes by second electric capacity (C2) and second auxiliary switch (S4) in parallel, wherein second auxiliary switch (S4) is consistent with second power switch pipe (S2) direction, and second electric capacity (C2) links to each other with the contact of second power switch pipe (S2) with first inductance (L1).