現(xiàn)代電力電子技術(shù)6 soft

第六章 諧振軟開(kāi)關(guān)變換器→20kHz革命★開(kāi)關(guān)電路能量變換的兩種方式：硬開(kāi)關(guān)：突變、強(qiáng)迫的能量變換；主導(dǎo)10W~500kW變換器Hard

SwitchingSoft

Switching軟開(kāi)關(guān)：自然、柔性的能量變換；LC諧振+ZCS/ZVS；80年代：DC-DC廣泛應(yīng)用/DC-AC遠(yuǎn)未成熟，控制策略：最佳離散脈沖調(diào)制相鄰空間電流矢量調(diào)制離散時(shí)間積分型滑?！G色革命★硬開(kāi)關(guān)對(duì)高頻變換的局限iCuCENSOA

LLZVS

fl

di

/

dtZCSfl

du

/

dtCL1、二次擊穿限制：參數(shù)最佳設(shè)計(jì)2、熱學(xué)限制：充分提高開(kāi)關(guān)頻率3、緩沖限制：極間電容分布參數(shù)可利用，降低成本，提高效率；4、EMI限制：硬開(kāi)關(guān)du/dt、di/dt→EMI①M(fèi)iller效應(yīng)：ΔUon大→Ig分流大，偶合干擾∨ZVS②CDS/CE

損耗：開(kāi)通時(shí)CU2OFF/2熱損耗于器件內(nèi)∨ZVS③

易與分布電感振蕩 ∨

利用于諧振SS★諧振變換器的分類(lèi)1、負(fù)載諧振變換器：①電壓源型串聯(lián)諧振變換器：串聯(lián)負(fù)載諧振變換器（SLR）并聯(lián)負(fù)載諧振變換器（PLR）混合諧振變換器②電流源型并聯(lián)諧振變換器（感應(yīng)加熱SCR）③E類(lèi)諧振變換器2、諧振開(kāi)關(guān)（準(zhǔn)諧振）變換器：①諧振開(kāi)關(guān)DC-DC變換器：零電流開(kāi)關(guān)變換器（ZCS）零電壓開(kāi)關(guān)變換器（ZVS）②零電壓開(kāi)關(guān)電壓鉗位（偽諧振）變換器（ZVS-CV）3、諧振直流環(huán)變換器4、高頻環(huán)整數(shù)半波變換器§6-1

負(fù)載諧振變換器1★

SLR串聯(lián)負(fù)載諧振變換器諧振等效電路：UiUoRLABCS1

D1D4D3

D5D6CUi/2Ui/2LiiLC3C1C2S2

D2CuLiCuAC

Ui/2Uo

=

-

i

=

+

i

L=

-

i

-

UOuACuAB=

+

i

-

UOUuACUuAB222U2U

S1

=

ON

D2

=

ONi

>

0

=

+

i

OACAB=

+

i

+

UOUuACuABu

=

-

Ui

+

Uu

=

-

Ui22

D1

=

ON22U

S

2

=

ONiL

<

0★導(dǎo)電規(guī)律：diL=

UACL

+

uCdtdtduCC=

iL解：w

0

=

1

/

LCZ0

=

L

/

CIL0

UC

0特征阻抗ZU

AC

-

UC

0sin

w

0

(t

-

t0

)iL

(t)

=

IL0

cos

w

0

(t

-

t0

)

+0uC

(t)

=

UAC

-

(U

AC

-

UC

0

)

cosw

0

(t

-

t0

)

+

Z0

IL0

sin

w

0

(t

-

t0

)1、斷續(xù)運(yùn)行方式（Ts>2To）w

0

tUi-UiTSS1

D1S2D2180

180180180t1t2

t32UO0-2UO全關(guān)斷iLuCTOiLACUi/2UoBiLACUi/2UoBACiLUi/2UoBAiLCUi/2UoBOAC-

U=

Ui2t

=

0

~

t1

uIL0

UC

0=

0

=

-2UO★OACu

=

Ui

+Ut

=

t1

~

t

2=

Ui2UC

0IL0=

0t1

=

0★uC

(t1)

=

UiiOL0Z0sinw

tU

+

U

/

2i

(t)

=U

UC

OO

022u

(t

)

=

( i

-

U

)

-

( i

+

U

)

cos

w

tuC

(t

2)

=

2UOZL00sin

w

tUO

-Ui

/

2i

(t)

=UUiOOiC022)

cosw

t+

U

)

-

(U

-u

(t

)

=

(斷續(xù)運(yùn)行方式（Ts>2To）w

0

tUi-2UO-UiTSS1

D1S2D2180

180180180t1t2

t32UO0全關(guān)斷iLuCTO★D：ZC開(kāi)通、關(guān)斷★S：S關(guān)斷后并聯(lián)D續(xù)流ZV+ZC關(guān)斷★S：開(kāi)通前全關(guān)斷，S懸空Z(yǔ)V+ZC開(kāi)通UiUoRABCS1

D1S2

D2D4D3

D5D6L

CUi/2Ui/2LiiLC3C1C2CuS

可采用半控開(kāi)關(guān)器件★調(diào)節(jié)全關(guān)斷時(shí)間可調(diào)節(jié)輸出電流iLACUi/2UOBACiLUi/2UOBACiLUi/2UOBiLACUi/2UOBw

0

tTSS1

D1S2D2<

180t1t2t30iLuC<

TO2、連續(xù)運(yùn)行方式—1（To

<

Ts

<

2To）★S：非ZC、非ZV開(kāi)通；但ZC+ZV關(guān)斷UiUoRABCS1

D1S2

D2D4D3

D5D6L

CUi/2Ui/2LiiLC3C1C2Cu★

D：ZC開(kāi)通但0和t2時(shí)，S1、S2流過(guò)

D2、D1的反向恢復(fù)電流（S非ZV開(kāi)通）3、連續(xù)運(yùn)行方式—2（

Ts

<

To）UiUoRLABCS1

D1S2

D2D4D3

D5D6CUi/2Ui/2LiiLC3C1C2CuS1D2S2D10ACiLUi/2UoBACiLUi/2UoBiLACUi/2UoBACiLUi/2UoBuCTSiLt1t

2t3w

0

t<

TO

/2S強(qiáng)迫關(guān)斷SZC+ZV開(kāi)通SLR

的頻率調(diào)節(jié)特性w

0

tUi-2UO-UiTSS1

D1S2D2180

180180180t1t2

t32UO0全關(guān)斷iLuCTO斷續(xù)模式★斷續(xù)模式的電流源特性UiUoRS1ABCD1S2

D2D4D3

D5D6L

CUi/2Ui/2LiiLC3C1C2Cuf

s/f

oIo1.00.50Uo=0.2UiUo=0.8UiZVSZCS連續(xù)模式f

sIoUo/Ui0.20.8fs反比于全關(guān)斷時(shí)間☆SLR諧振的缺點(diǎn)：S、L峰值電流較大2并聯(lián)負(fù)載諧振變換器★PLR諧振等效電路：UiUoRABCS1

D1S2

D2D4D6CUi/2Ui/2LiiOC3C1C2CL

iD3

D5

L1iLiCACUi/2IOBdt-

L

diLuC

=

UABiL

-

iC

=

IOdt

2d

2

idtduiC

=

C C

=

-LC

L

22dt

2d

2iiL

=

w

0

IO L

+w

0w

0

=

1

/

LCZ0

=

L

/

CIL0

UC

0ZL0UAB

-UC

0iL

(t)

=

IO

+

(Isinw

0

(t

-

t0

)-

IO

)

cosw

0

(t

-

t0

)

+0uC

(t)

=

UAB

+

(UAB

-

UC

0

)

cos

w

0

(t

-

t0

)

+

Z0

(IL0

-

IO

)

sin

w

0

(t

-

t0

)★導(dǎo)電規(guī)律：△設(shè)電感L1足夠大，Ts內(nèi)電流恒定：

2=

-

i

AB=

+

i

2UUuAB

S1

/

D1

=

ON

:

S

2

/

D2

=

ON

:

u斷續(xù)運(yùn)行方式（Ts>2To）UiUoRABCS1

D1S2

D2D4D3

D5D6CUi/2Ui/2LiiOC3C1C2CL

iL1w

0

tTSS1D1S2D2t1t2IO0iLuCt3t4t5全關(guān)斷全關(guān)斷iLCiACUi/2IoBACUi/2IoBIoiLACUi/2BuC

=

0ACUi/2BIo★S：開(kāi)通前全關(guān)斷，S懸空Z(yǔ)V+ZC開(kāi)通★S：S關(guān)斷后并聯(lián)D續(xù)流ZV+ZC關(guān)斷★D：ZC開(kāi)通、關(guān)斷深色線為直線PLR

的頻率調(diào)節(jié)特性斷續(xù)模式★斷續(xù)模式的電壓源特性連續(xù)模式UiUoRABCS1

D1S2

D2D4D6CUi/2Ui/2LiiOC3C1C2L

iCD3

D5

L1w

0

tIOTSS1D1S2D2t1t20iLuCt3t4t5全關(guān)斷全關(guān)斷f

s/f

oUo1.00.50Io=0.2IBaseIo=0.8IBaseZVSZCS0ZIBase=

Ui

/

2f

sUoIo/IBase0.20.8☆PLR諧振的缺點(diǎn)：

C峰值電壓較大3E類(lèi)負(fù)載諧振DC-AC變換器★

S：ZC+ZV

ONZV

OFFC1CLRL1OiiiiCiSSUiiOIi-Iiw

0

tiSiCuCUiw

0

tw

0

tw

0

t0.5TsUi

=UC0.5TsS=OFFS=ONiS

=

ii

+iOiC

=

ii

+iOCLROiSiiCIiC1CLROi

iSiCS★AC輸出調(diào)節(jié)：Sf0Z

>>

ZiO

/

pO★最佳控制模式：①L1足夠大，Ts內(nèi)電流恒定；②開(kāi)關(guān)頻率=串聯(lián)諧振頻率+；③

D=0.5④t=Ts時(shí)使duc/dt=0

即ic=0，否則S并二極管，保證ZCon為次最佳模式?！?-2

開(kāi)關(guān)（準(zhǔn)）諧振變換器1ZCS

諧振開(kāi)關(guān)變換器（Buck例）iCw

0

tuDw

0

tw

0

t1iSIOuCUiUOw

0

t2UiUi-UiUi

-uC234IODTDiiSUiIouC

=UiU