CN112600428B - 有源箝位交错不对称反激式直流变换器 - Google Patents

有源箝位交错不对称反激式直流变换器 Download PDF

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CN112600428B
CN112600428B CN202010747411.2A CN202010747411A CN112600428B CN 112600428 B CN112600428 B CN 112600428B CN 202010747411 A CN202010747411 A CN 202010747411A CN 112600428 B CN112600428 B CN 112600428B
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transformer
converter
phase
switch tube
flyback
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CN112600428A (zh
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江加辉
马大壮
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Qingdao University
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00Conversion of dc power input into dc power output
    • H02M3/22Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/3353Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having at least two simultaneously operating switches on the input side, e.g. "double forward" or "double (switched) flyback" converter
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00Conversion of dc power input into dc power output
    • H02M3/22Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33569Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
    • H02M3/33576Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
    • H02M3/33592Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

一种新颖的有源箝位交错不对称反激式直流变换器,是由输入直流电源、输入滤波电路、两相交错不对称反激式斩波电路、输出滤波电路依序级联构成。该变换器在传统有源箝位交错反激式直流变换器的基础上,通过交换一相反激式变换器的变压器支路和有源箝位支路,增加其等效输入电压进而提高了变换器的升压能力,在保证电压增益不变时,可减小储能式变压器原边绕组匝数,进而减小变压器漏感及变压器原边电阻,降低了变压器原边损耗,提高变换器效率。此外,变压器副边功率开关采用同步整流,有效降低副边导通损耗,实现了该变换器的高效变换。与传统有源箝位交错反激式直流变换器相比,该变换器具有更低的电流应力、更强的升压能力,为宽输入电压范围、低电压大电流的中小功率开关电源提供了一种高性能、低成本的解决方案。

Description

有源箝位交错不对称反激式直流变换器
技术领域
本发明涉及开关电源技术领域,特别涉及一种交错反激式变换器,属于电力电子变换技术。
背景技术
当前,开关电源因小型、轻量和高效率的特点被广泛应用于工业控制、军工设备、服务器电源、LED照明、通讯设备等领域,已成为当今电子信息产业飞速发展不可或缺的一种供电方式。其中,对于中小功率场合,尤其是针对低输入电压、宽输入电压范围和高效率应用场合,例如通信电源系统、数据中心供电系统以及小型电动汽车电源系统,反激式变换器因简单可靠而得以广泛应用。图1所示的传统有源箝位交错反激式直流变换器工作在对称模式,A、B相变换器的输入电压均为输入电源电压,变换器的升压能力有限,在低压大电流场合时,变压器原边绕组导通损耗大且变压器原边匝数多带来的变压器漏感大这一问题,导致了漏感能量损耗大以及储能开关电压应力高,现有的有源箝位交错反激式直流变换器难以满足宽输入电压范围、低电压大电流场合时开关电源对高效率变换和高功率密度的要求。
因此,积极寻求一种具有更高效率、更强升压能力的有源箝位交错反激式直流变换器迫在眉睫,对于减少中小功率、低电压大电流开关电源系统的功耗和成本、提高输入电压范围具有重要意义。
发明内容
本发明的目的是提供一种具有高电压增益、宽输入电压范围、低原边导通损耗、低漏感损耗、常规输入电压下最高效率等优点的有源箝位交错不对称反激式直流变换器,如图2所示,本发明所提供的直流变换器,能够适用于低电压大电流的中小功率场合,极大地优化了交错反激式变换器的特性。
本发明所采用的技术方案是:通过交换一相反激式变换器的变压器支路和有源箝位支路,增加其等效输入电压进而提高了变换器的升压能力,在保证电压增益不变时,可减小储能式变压器原边绕组匝数,进而减小变压器漏感及变压器原边电阻,降低了变压器原边损耗,提高变换器效率。此外,变压器副边功率开关采用同步整流,有效降低副边导通损耗,实现了该变换器的高效变换。
本发明技术方案为一种有源箝位交错不对称反激式直流变换器,该变换器是由输入直流电源、输入滤波电路、两相交错不对称反激式斩波电路、输出滤波电路依序级联构成。其中,两相交错不对称反激式斩波电路由A相反激式斩波电路B相反激式斩波电路并联构成。所述的A相反激式斩波电路由A相主开关管(Q1)、箝位开关管(Q2)、箝位电容(CB1)、变压器(T1)、副边整流开关管(SR1)构成,变压器(T1)一端连接电源VS正极,另一端连接主开关管(Q1)的漏极和箝位开关管(Q2)的源极,主开关管(Q1)的源极连接电源VS负极,箝位开关管(Q2)的漏极连接箝位电容(CB1)的一端和B相变压器(T2)的一端,箝位电容(CB1)的另一端连接电源VS正极,变压器(T1)副边一端与整流开关管(SR1)的漏极相连,另一端与输出滤波电容(CO)的一端相连,输出滤波电容(CO)的另一端与整流开关管(SR1)的源极相连;所述的B相反激式斩波电路由B相主开关管(Q3)、箝位开关管(Q4)、箝位电容(CB2)、变压器(T2)、副边整流开关管(SR2)构成,变压器(T2)一端与A相箝位开关管(Q4)漏极和A相箝位电容(CB1)的一端相连,另一端与主开关管(Q3)漏极和箝位开关管(Q4)源极相连,主开关管(Q3)源极连接电源VS负极,箝位开关管(Q4)另一端连接箝位电容(CB2),箝位电容(CB2)的另一端连接电源VS正极和变压器(T1)的一端,变压器(T2)副边一端与整流开关管(SR2)的漏极相连,另一端与输出滤波电容(CO)的一端相连,输出滤波电容(CO)的另一端与整流开关管(SR2)的源极相连。
具体方法为:一种新颖的有源箝位交错不对称反激式直流变换器,由输入直流电源、输入滤波电路、两相交错不对称反激式斩波电路、输出滤波电路构成主电路;两相反激式变换器主开关管交错导通且相位差为180°,每相反激变换器的主开关管和箝位开关管互补导通,副边整流开关管同步整流。当A相主开关管Q1导通时,变压器T1励磁电感励磁,其两端电压为电源电压VS,电感电流线性增加,当A相主开关管Q1关断时,副边开关管导通,以此降低开关管电压应力,降低选型要求。对于B相反激式变换器,当B相主开关管Q2导通时,变压器T2励磁电感励磁,其两端电压为VS+VCB1,即电源电压与A相箝位电容电压之和,极大地提高了B相等效输入电压,B相反激式变换器电压增益增加,在相同电压增益条件下,对于变压器设计,可以减小原边绕组匝比,从而能够减小变压器漏感和绕组线路电阻,进而减小变压器原边导通损耗和漏感能量损耗,因此,可以提高B相反激式变换器的效率。B相反激式变换器副边工作方式同样采用同步整流方式。
控制方式为:一种新颖的有源箝位交错不对称反激式直流变换器,一相相变换器采用电压环路恒压输出控制,两相变换器采用主从均流法进行均流控制,控制方式如图3所示。
所述新颖的有源箝位交错不对称反激式直流变换器通过交换一相反激式变换器的变压器支路和有源箝位支路,将该相反激式变换器的输入电压由电源电压VS提升为电源电压VS与A相反激式变换器的箝位电容电压VCB1之和,提高其等效输入电压,进而可以优化变压器匝数和漏感,能够在同等条件下,降低变换器原边导通损耗和漏感损耗,提升变换器整体效率。因此A相箝位电容CB1既做为A相反激式变换器的有源箝位电容,同时又具有提高B相反激式变换器等效输入电压的作用,其主要思想是将箝位电容CB1做为中间储能电容与箝位电容而参与电路工作,在无额外增加电路元件的基础之上,增加了B相反激式变换器的等效输入电压,从而能够优化电路参数,使新颖的有源箝位交错不对称反激式直流变换器具有宽输入电压范围和更高效率的优点。
充分考虑电路在实际工作状态下的特性,通过对变压器原副边匝比、励磁电感量以及漏感量进行了详细分析,对电路一个稳态周期内的开关状态和电路参数进行详细说明,实现所述变换器适应宽输入电压范围以及低电压大电流的中小功率场合,具有高效率和高功率密度特性。
与现有技术相比,本发明的有益效果是:
与传统交错反激式直流变换器相比,本发明具有更高的等效输入电压。
与传统交错反激式直流变换器相比,本发明具有更高的电压传输增益,同等条件下,变压器匝数减小,从而原边绕组电阻减小,漏感减小,进而原边导通损耗和漏感损耗显著降低。
与传统交错反激式直流变换器相比,本发明在额定状态下,具有更高的效率。
与传统交错反激式直流变换器相比,本发明的变换器副边采用同步整流方式,副边损耗显著降低。
下面结合附图和具体实施方式对本发明作进一步说明。
附图说明
图1为传统有源箝位交错反激式直流变换器的电路拓扑。
图2为新颖的有源箝位交错不对称反激式直流变换器电路拓扑。
图3为新颖的有源箝位交错不对称反激式直流变换器控制框图。
图4、图5为新颖的有源箝位交错不对称反激式直流变换器工作波形图。
图6、图7为新颖的有源箝位交错不对称反激式直流变换器工作模态图。
具体实施方式
下面通过具体实例结合附图对本发明做进一步详细的描述。
如图4、图5、图6、图7所示,当电路工作在CCM模式时有四个模态。
模态1:工作模态1对应图4、图5、图6、图7中a图,在此阶段,对于(D1,D2<0.5):主开关管Q1和箝位开关管Q4导通,A相变压器励磁电感励磁,B相副边开关管导通,变压器T2储存的能量通过SR2输出至负载和滤波电容;对于(D1,D2>0.5):主开关管Q1和主开关管Q3导通,A相和B相变压器励磁电感励磁,励磁电感电流线性增加,副边整流开关管均关闭,副边输出截止。
模态2:工作模态2对应图4、图5、图6、图7中b图,在此阶段,对于(D1,D2<0.5):箝位开关管Q2和箝位箝位开关管Q4导通,两相变压器副边开关管均导通,变压器储存的能量输出至负载和滤波电容;对于(D1,D2>0.5):主开关管Q1和箝位箝位开关管Q4导通,A相励磁电感励磁,B相副边开关管导通,变压器T2储存的能量通过SR2输出至负载和滤波电容。
模态3:工作模态3对应图4、图5、图6、图7中c图,在此阶段,对于(D1,D2<0.5):箝位箝位开关管Q2和主开关管Q3导通,A相变压器副边开关管导通,变压器T1储存的能量通过SR1输出至负载和滤波电容;对于(D1,D2>0.5):主开关管Q1和主开关管Q3导通,A相和B相变压器励磁电感励磁,励磁电感电流线性增加,副边整流开关管均关闭,副边输出开关管截止。
模态4:工作模态4对应图4、图5、图6、图7中d图,在此阶段,对于(D1,D2<0.5):箝位箝位开关管Q2和箝位箝位开关管Q4导通,两相变压器副边开关管均导通,变压器储存的能量输出至负载和滤波电容;对于(D1,D2>0.5):箝位箝位开关管Q2和主开关管Q3导通,A相变压器副边开关管导通,变压器T1储存的能量通过SR1输出至负载和滤波电容。

Claims (1)

1.一种有源箝位交错不对称反激式直流变换器,其特征在于:该变换器是由输入直流电源、输入滤波电路、两相交错不对称反激式斩波电路、输出滤波电路依序级联构成,其中,两相交错不对称反激式斩波电路由A相反激式斩波电路B相反激式斩波电路并联构成,所述的A相反激式斩波电路由A相主开关管(Q1)、箝位开关管(Q2)、箝位电容(CB1)、变压器(T1)、副边整流开关管(SR1)构成,变压器(T1)一端连接电源VS正极,另一端连接主开关管(Q1)的漏极和箝位开关管(Q2)的源极,主开关管(Q1)的源极连接电源VS负极,箝位开关管(Q2)的漏极连接箝位电容(CB1)的一端和B相变压器(T2)的一端,箝位电容(CB1)的另一端连接电源VS正极,变压器(T1)副边一端与整流开关管(SR1)的漏极相连,另一端与输出滤波电容(CO)的一端相连,输出滤波电容(CO)的另一端与整流开关管(SR1)的源极相连;所述的B相反激式斩波电路由B相主开关管(Q3)、箝位开关管(Q4)、箝位电容(CB2)、变压器(T2)、副边整流开关管(SR2)构成,变压器(T2)一端与A相箝位开关管(Q4)漏极和A相箝位电容(CB1)的一端相连,另一端与主开关管(Q3)漏极和箝位开关管(Q4)源极相连,主开关管(Q3)源极连接电源VS负极,箝位开关管(Q4)另一端连接箝位电容(CB2),箝位电容(CB2)的另一端连接电源VS正极和变压器(T1)的一端,变压器(T2)副边一端与整流开关管(SR2)的漏极相连,另一端与输出滤波电容(CO)的一端相连,输出滤波电容(CO)的另一端与整流开关管(SR2)的源极相连。
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