CN1385954A

CN1385954A - Phase-shift controlled bidirectional dc-dc converter

Info

Publication number: CN1385954A
Application number: CN02112194A
Authority: CN
Inventors: 徐德鸿; 赵川红; 陈刚
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2002-06-21
Filing date: 2002-06-21
Publication date: 2002-12-18
Anticipated expiration: 2022-06-21
Also published as: CN1174543C

Abstract

A phase shift control two-way DC-DC alternator is composed of a host and a control circuit. The host contains four switch tubes M1-M4 clamp capacitor (Cc1) blocking capacitors Ct1 Ct2, filter inductance Lo and isolating transformer T and the control circuit contains phase shift control chips connected two PWM control chips at the output. The positive end of error amplifier of each control chip is connected with a duty rate control signal and the output is divided into two, connected separately with the input of two data selectros, the outupt dignals of which is divided into two parts, one inputs to the host driver, the other inputs to the host drive via NOT gate to output drive signals controlling host switch tubes, so as to reduce the current stress of alternators and effective values realizing soft switch work.

Description

Phase-shift controlled bidirectional dc-DC converter

Technical field

The present invention relates to phase-shift controlled bidirectional dc-dc converter.

Background technology

In order to reduce the volume and weight of bidirectional, dc-DC converter, must improve switching frequency.And the increase that the raising of switching frequency must bring switching loss in traditional converter.In these years, the scheme that addresses this problem has appearred.Wherein some adopts resonance, quasi-resonance or the multi resonant technology of shaking, but the electric current and voltage stress of converter is higher, and variable frequency control has increased the difficulty of Design of Filter; Some adds energy snubber and absorbs circuit or active clamp circuit, but has increased the complexity of converter and control; Also some adopts the full-bridge phase-shift technology, such transformer configuration is simple, components and parts are few, weak point is when a side voltage deviation equilibrium valve, the current peak and the effective value of converter increase greatly, certainly will increase the exchange of reactive power between input and the output,, increase loss so increase the current stress of power device, magnetic element.

Summary of the invention

The purpose of this invention is to provide a kind of simple in structurely, can reduce the peak value of electric current and the phase-shift controlled bidirectional dc-dc converter of effective value.

Phase-shift controlled bidirectional dc-DC converter of the present invention has main circuit and control circuit two parts, and main circuit comprises four switching tube M ₁～M ₄, clamp capacitor Cc1, capacitance Ct1, Ct2, filter inductance L ₀With isolating transformer T, be connected across the switching tube M that is in series behind the former limit serial connection capacitance Ct1 of isolating transformer T ₁, M ₂One of them switching tube M ₂Two ends, these two switching tube M ₁, M ₂Series circuit and DC power supply V ₁Parallel connection, behind the secondary of the isolating transformer T serial connection capacitance Ct2 with switching tube M ₄, switching tube M ₃Series circuit, filter inductance L with clamp capacitor Cc1 ₀With active load V ₂Series circuit be in parallel; Control circuit comprises that two inputs connect the phase shift control chip of given power signal and feedback power signal respectively, the output signal of phase shift control chip divides two the tunnel, respectively with first, the synchronous end of the second two pwm chips links to each other, the positive termination duty cycle control signal of the error amplifier of each pwm chip, output divides two the tunnel, connect first respectively, the input of second data selector, first, the public input of the second two data selectors is just connecing respectively, reverse control signal, the output signal of data selector divides two the tunnel, one road input main circuit driver, another road is through not gate input main circuit driver, said main circuit driver comprises the rising edge delay circuit, buffer circuit and drive circuit, the signal of input main circuit driver is defeated by buffer circuit through the rising edge delay circuit, the input of the output termination drive circuit of buffer circuit, the drive signal of No. four drive circuits output is defeated by main circuit switch pipe M respectively ₁～M ₄

Phase-shift controlled bidirectional dc-DC converter of the present invention is on the basis of phase shift control transmission watt level and direction, according to the both sides voltage magnitude, follow the tracks of the duty ratio of regulating PWM, can effectively reduce the current stress and the current effective value of converter, and converter can be realized soft switch work, thereby can raise the efficiency.

Description of drawings

Fig. 1 is a main circuit of the present invention;

Fig. 2 is a control circuit block diagram of the present invention;

Fig. 3 is a circuit theory waveform of the present invention.

Embodiment

Phase-shift controlled bidirectional dc-the DC converter of invention has main circuit and control circuit two parts, and main circuit is with reference to Fig. 1, and it comprises four switching tube M ₁～M ₄, clamp capacitor Cc1, capacitance Ct1, Ct2, filter inductance L ₀With isolating transformer T, switching tube can be power field effect transistor, power bipolar transistor or insulated door gated transistors or other controlled switching device, what legend adopted is power field effect transistor, is connected across the switching tube M that is in series behind the former limit serial connection capacitance Ct1 of isolating transformer T ₁, M ₂One of them switching tube M ₂Two ends, these two switching tube M ₁, M ₂Series circuit and DC power supply V ₁Parallel connection, L among the figure ₁It is the leakage inductance of isolating transformer.Behind the secondary of the isolating transformer T serial connection capacitance Ct2 with switching tube M ₄, switching tube M ₃Series circuit, filter inductance L with clamp capacitor Cc1 ₀With active load V ₂Series circuit be in parallel; Control circuit as shown in Figure 2, it comprises that two inputs connect the phase shift control chip 1 of given power signal A and feedback power signal B respectively, the output signal of phase shift control chip divides two the tunnel, link to each other with the synchronous end of first, second two pwm chips 2 respectively, the positive termination duty cycle control signal of the error amplifier of each pwm chip D, D=NV ₂/ V ₁N is the transformer number of turn, output divides two the tunnel, connect first respectively, the input of second data selector 3, first, the public input of the second two data selectors is just connecing respectively, reverse control signal E, the output signal of data selector divides two the tunnel, one road input main circuit driver 8, another road is through not gate 4 input main circuit drivers 8, said main circuit driver 8 comprises rising edge delay circuit 5, buffer circuit 6 and drive circuit 7, and the signal of input main circuit driver is defeated by buffer circuit 6 through rising edge delay circuit 5, the input of the output termination drive circuit 7 of buffer circuit, the drive signal V of No. four drive circuits output _G1, V _G2, V _G3, V _G4Be defeated by main circuit switch pipe M respectively ₁～M ₄Gate pole.

Here, the phase shift control chip can adopt UC3875, and pwm chip can be used UC3525A.

The course of work of converter is with reference to Fig. 3, and figure (a)～figure (d) is switching tube M ₁～M ₄Gate electrode drive signals, figure (e) is a voltage waveform between main circuit a, b contact, figure (f) is the voltage waveform between main circuit c, d contact, figure (g) is converter leakage inductance L ₁Voltage waveform, figure (h) be L ₁Current waveform.

In the converter work, four switching tube M ₁, M ₂, M ₃And M ₄Switching frequency identical, M wherein ₁And M ₃Drive controlling keep identical duty ratio D, M ₂With M ₁Drive controlling be complimentary fashion, M ₄With M ₃Drive controlling be complimentary fashion.By control M ₁And M ₃The phase relation of drive signal reaches two DC source V of control ₁And V ₂Between the size and Orientation of power transfer.Work as V ₁Or/and V ₂During the voltage deviation equilibrium valve, at switching tube M ₁And M ₃Time period of conducting simultaneously (figure h, t2～t3 time period) and switching tube M ₂And M ₄The time period of conducting simultaneously (figure h, t4～t5 time period) converter current remains unchanged, and can reduce current stress like this, reduces the loss of current effective value and converter.

The switching tube M of transformer the same side ₁(or M ₃) and switching tube M ₂(or M ₄) carry out in the switch handoff procedure, because transformer leakage inductance L ₁Existence, switching tube such as M therein ₁Have no progeny in the pass, the electric current in the leakage inductance will be to another switching tube M of homonymy ₂Two ends and the equivalent capacity discharge that connects, latter M afterwards ₂Will be by open-minded under the no-voltage situation.Like this, converter all can be realized soft switch work in two-way operation.After arbitrary switching tube was turned off, its both end voltage all was clamped on the fixed voltage, high voltage stress and vibration can not occur.

Claims

1. phase-shift controlled bidirectional dc-DC converter is characterized in that having main circuit and control circuit two parts, and main circuit comprises four switching tube M ₁～M ₄, clamp capacitor Cc1, capacitance Ct1, Ct2, filter inductance L ₀With isolating transformer T, be connected across the switching tube M that is in series behind the former limit serial connection capacitance Ct1 of isolating transformer T ₁, M ₂The two ends of one of them switching tube M2, these two switching tube M ₁, M ₂Series circuit and DC power supply V ₁Parallel connection, behind the secondary of the isolating transformer T serial connection capacitance Ct2 with switching tube M ₄, switching tube M ₃Series circuit, filter inductance L with clamp capacitor Cc1 ₀With active load V ₂Series circuit be in parallel; Control circuit comprises that two inputs connect the phase shift control chip (1) of given power signal and feedback power signal respectively, the output signal of phase shift control chip divides two the tunnel, respectively with first, the synchronous end of the second two pwm chips (2) links to each other, the positive termination duty cycle control signal of the error amplifier of each pwm chip, output divides two the tunnel, connect first respectively, the input of second data selector (3), first, the public input of the second two data selectors is just connecing respectively, reverse control signal, the output signal of data selector divides two the tunnel, one road input main circuit driver (8), another road is through not gate (4) input main circuit driver (8), said main circuit driver (8) comprises rising edge delay circuit (5), buffer circuit (6) and drive circuit (7), the signal of input main circuit driver is defeated by buffer circuit (6) through rising edge delay circuit (5), the input of the output termination drive circuit (7) of buffer circuit, the drive signal of No. four drive circuits output is defeated by main circuit switch pipe M respectively ₁～M ₄