CN1048122C - 开关电源 - Google Patents
开关电源 Download PDFInfo
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- CN1048122C CN1048122C CN91100910A CN91100910A CN1048122C CN 1048122 C CN1048122 C CN 1048122C CN 91100910 A CN91100910 A CN 91100910A CN 91100910 A CN91100910 A CN 91100910A CN 1048122 C CN1048122 C CN 1048122C
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS 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
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion 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
- H02M3/325—Conversion 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
- H02M3/335—Conversion 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
- H02M3/33507—Conversion 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 with automatic control of the output voltage or current, e.g. flyback converters
- H02M3/33523—Conversion 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 with automatic control of the output voltage or current, e.g. flyback converters with galvanic isolation between input and output of both the power stage and the feedback loop
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F19/00—Fixed transformers or mutual inductances of the signal type
- H01F19/04—Transformers or mutual inductances suitable for handling frequencies considerably beyond the audio range
- H01F19/08—Transformers having magnetic bias, e.g. for handling pulses
- H01F2019/085—Transformer for galvanic isolation
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS 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
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion 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
- H02M3/325—Conversion 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
- H02M3/335—Conversion 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
- H02M3/33561—Conversion 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 more than one ouput with independent control
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS 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
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion 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
- H02M3/325—Conversion 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
- H02M3/335—Conversion 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
- H02M3/33569—Conversion 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
- H02M3/33576—Conversion 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
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- Power Engineering (AREA)
- Engineering & Computer Science (AREA)
- Dc-Dc Converters (AREA)
- Selective Calling Equipment (AREA)
- Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
- Networks Using Active Elements (AREA)
- Amplifiers (AREA)
- Air Bags (AREA)
- Oscillators With Electromechanical Resonators (AREA)
- Transmitters (AREA)
- Circuit For Audible Band Transducer (AREA)
- Train Traffic Observation, Control, And Security (AREA)
- Exchange Systems With Centralized Control (AREA)
- Emergency Protection Circuit Devices (AREA)
- Circuits Of Receivers In General (AREA)
Abstract
对有一个变压器的开关电源附加一个与二极管(D1)并联的晶体管(T2),充电电流(iD)衰减之后,该晶体管(T2)在开关晶体管(T1)导通的一部分期间内受工作电压(U5)的控制而导通,并且该晶体管(T2)通过一个与充电电流(iD)方向相反的反向电流(iT2)将能量从充电电容器(4)反馈至变压器(Tr),在原边从由反向电流(iT2)感应的电压(U2)中得到调整电压(UT)。
Description
本发明涉及一种它带有一个变压器的开关电源。
在这种开关电源中,通过调节(调整)原边开关晶体管的导通时间(占空系数),使副边工作电压的幅度得到稳定。然而,必须将表明相应的工作电压实际值幅度的调整信息,从副边传送至原边。不过在进行这种传送的时候,原边和副边之间必须保持电隔离。因此,众所周知需要一个附加电路,例如,一个隔离变压器或一个光耦合器,用来将调整信息从副边传至原边。
本发明的目的是以一种简单的电方式,在实现将调整信息从副边传至原边的同时保持电隔离,而无需附加电路。
本发明的开关电源可以完成这任务。它有一个变压器,变压器的副边绕组通过一个二极管(D)向充电电容器(4)提供充电电流(iD),在电容器两端得到工作电压(U5),因此,在原边得到依赖于副边工作电压(U5)的调整电压(Ur),用于控制开关晶体管(T1)的导通时间(占空系数),其特征在于有一个与二极管(D1)并联的晶体管(T2),充电电流(iD)衰减之后,该晶体管(T2)在开关晶体管(T1)导通的一部分期间内受工作电压(U5)的控制而导通,并且该晶体管(T2)通过一个与充电电流(iD)方向相反的反向电流(iT2)将能量从充电电容器(4)反馈至变压器(Tr),在原边从由反向电流(iT2)感应的电压(U2)中得到调整电压(Ur)。其它有益的改进之处见于从属权利要求。
根据本发明,总是需要用来进行电隔离以及将原边的电能传至副边的变压器,另外还用来将调整信息从副边传至原边。这种信息传送发生在变压器的所谓休止期,在这一期间,通过原边绕组的电流被电源开关切断。与信息同时传送的能量或反馈回变压器的能量因此而保持相当小的水平。原边的调整电压可以从一个电压部分得到,它依赖于相应的反向电流的实际值以及副边产生的工作电压的值。最好在休止期利用时间窗口(time-window)对原边的电压进行测定。于是调整电压仅从该时间窗口的电压部分获得。调整电压也可能从一个脉冲沿的陡度式幅度得到,它也依赖于反向电流以及副边产生的工作电压的值。对于传送信息来说,在变压器中不需要附加的绕组。利用一个整流器电流同时产生工作电压的副边绕组可以用来传送信息。副边绕组于是在工作期间向整流器电路提供能量。而在休止期间向原边传送控制信息。因此,能量的传送和信息的传送通过相同的绕组进行,然而是在不同的时间和不同的方向。
这样,变压器中的脉冲电压的特定部分可以测定调整变量。然而,为了测定该脉冲部分以得到调整变量可能通过不同的方法。
在第一种解决问题的方法中,脉冲电压在时间窗口期间利用一个开关脉冲而将其键控关断。开关脉冲来自控制开关电源的处理器。处理器装有包含调整信息的电压部分出现在工作期间内哪一段时间的信息。为了得到调整电压,该电压部分由时间窗口将其键控关断并且整流。在第二种解决问题的方法中,键控脉冲从脉冲电压本身获得。各个脉冲沿通过微分元件测定。于是就有可能得到一个标志时间窗口开始的脉冲。然后,从脉冲整形电路中的该脉冲可以产生延续整个时间窗口期间的所需要的键控脉冲。
下面根据附图说明本发明的不同的实施例。
图1是根据第一种解决问题方法的以简化形式画出的开关电源;
图2是根据第二种解决问题方法的电路实例;
图3是图1和图2中电压和电流波形。
图1中,端子1接有一个正的工作电压+U6,它是通过对交流电源进行整流后得到的。Us经变压器Tr的原边绕组W1连接至作为开关的功率晶体管T1。晶体管T1由具有电压2的处理器P控制,它被按照该电压的脉冲宽度来调制。工作电压U1、U2、U3、U4和U5由几个副边绕组和相连的整流器产生。ROD衰减器3,也称作“缓冲器”,与原边绕组W1并联。它限制脉冲峰值及T1上电压边缘的陡度。
晶体管T2与二极管D1并联,方向相反,它由比较器电路V在其基极进行控制。工作方式结合图3予以说明。从时刻t1至t2,电流i1流经原边绕组W1和晶体管T1。从时刻t2至t3,电流iD流经二极管D1,对充电电容器4进行充电。在时刻t3,晶体管T2变为导通,将所谓的反向电流iT2从充电电容器4反馈至变压器Tr。用这种方法传送的能量相对很小。在时刻t4,晶体管T2截止。从时刻t4至t5,通过反向电流iT2,由脉冲电压Us产生电压U2。U2的幅度取决于iT2。在比较器电路V,工作电压U5与齐纳二极管5上恒定的基准电压Ref进行比较。根据这一比较结果,控制晶体管T2导通时间长短,从而使iT2和U2也依赖于U5。
于是包含一个调整信息的电压U2也出现在原边绕组W2,其电压为UP,与US相位相反。在处理器P的脉冲整形器6中,键控脉冲UT来自电压UB,该电压周期性地控制晶体管导通和截止。键控脉冲UT以一个时间窗口控制开关7,于是UP中只有U2部分被测定。从以时间选择方式键控断开的电压U2且通过整流器8,在电容器15可以得到调整电压Ur1,它表示各个实际的U5偏离所要求值的程度。在比较器单元9,Ur1与从电压源10来的基准电压进行比较。由此得到的调整电压Ur2以这样一种方式控制脉冲宽度调制器11,即从稳定工作电压U1至U5的意义上调整电压2的脉冲宽度。这样,调整电压Ur2的依据是在时间触发脉冲t4至t5电压部分US或UP的幅度。时间窗口t4至t5大约为晶体管T1导通时间的10~20%。键控脉冲UT必须在整个期间t4至t5延续。根据图3,该键控脉冲UT持续时间更长,即从t2至t5,因为它最好从电路中得到。在这种情况下,通过开关7,从t2至t4的UP部分也被接转。然而,其负的部分由于二极管8的作用而受到抑制,结果只有从t4至t5期间的电压U2通过二极管8进一步得到传送,从而产生Ur1。电路具有以下附加的优点:通常需要一个与充电电容器4并联的附加的分流电阻,它也称作“分流器”,为电容器放电提供一个通路。根据图1的电路,该分流电阻可以具有较高的欧姆值,以致于释放的功率较小。根据要求,作为晶体管T2作用的结果,分流电阻也可以完全取消。
图2表示产生键控脉冲UT的另一种可行的电路。利用微分元件12,从电压UP得到电压UP′。利用微分元件13,从T1基极的电压UB得到电压UB′、UP′和UB′在加法器14中相加,由此产生电压Ud1。t1至t5期间的负脉冲UP′和此期间的正脉冲UB′相加,且部分抵消,而t4时刻UP′中的负电压得以保留。利用二极管16,从电压Ud1得到电压Ud2,而前者在t4时刻具有负尖峰。在一个脉冲整形器或一个单稳电路中可以使用电压Ud2,用于产生时间窗口t4至t5的键控脉冲UT。
Claims (6)
1.一种带有一个变压器(Tr)的开关式电源,该变压器含有一个初级绕组(W1)和一个次级绕组,
该初级绕组(W1)与一个开关晶体管(T1)串联连接,该开关晶体管根据有荷占空度的要求而导通,以便经过该初级绕组(W1)给该变压器(Tr)充电,
该次级绕组经过一个二极管(D1)给一个充电电容器(4)提供充电电流(iD),以便产生工作电压(U5),
一个晶体管(T2),与所述的二极管(D1)并联,被控制得可在所述的开关晶体管(T1)根据所述的工作电压(U5)的要求而被截止以后才被导通,并且借助于在针对该充电电容器(4)的反向上流动的反向充电电流(iT2),将能量反馈给该变压器(Tr),
在该初级侧,可以得到与所述的能量有关的并且因此与次级侧的工作电压(U5)有关的控制电压(Ur),用以控制该开关晶体管(T1)的有荷占空度,
其特征在于:
一个RCD衰减器(3),它含有一个电容器、一个电阻器和一个二极管,且与所述的初级绕组并联连接,用以限制脉冲峰值和在所述的开关晶体管(T1)上呈现的电压的边沿陡度,并且产生一个振荡电压(U2),及
在所述的初级侧上的控制电压(Ur)是从所述的反向充电电流(iT2)所感应的所述的振荡电压(U2)获得的。
2.根据权利要求1的电源,其特征在于,晶体管(T2)由一个比较电路(V)控制,工作电压(U5)与一个基准电压(Ref)在比较电路(V)中相比较。
3.根据权利要求1的电源,其特征在于,一个初级绕组(W2)通过一个在时间窗口(t4)至(t5)期间由开关脉冲(UF)使之工作的开关(8)与整流器(8)相连通,提供出调整电压(Ur1)。
4.根据权利要求2的电源,其特征在于,开关脉冲(UT)是从一个控制开关电源的处理器(2)得到的,并且在工作期间具有确定的瞬时位置。
5.根据权利要求2的电源,其特征在于,开关脉冲(UT)是从变压器(Tr)的初级绕组或次级绕组的一个电压脉冲沿得到的。
6.根据权利要求2的电源,其特征在于:晶体管(T1)导通时间的一部分是全部导通时间的10-20%。
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DEP4004707.5 | 1990-02-15 | ||
DE4004707A DE4004707A1 (de) | 1990-02-15 | 1990-02-15 | Schaltnetzteil |
DE4004707.5 | 1990-02-15 |
Publications (2)
Publication Number | Publication Date |
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CN1055451A CN1055451A (zh) | 1991-10-16 |
CN1048122C true CN1048122C (zh) | 2000-01-05 |
Family
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Application Number | Title | Priority Date | Filing Date |
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CN91100910A Expired - Fee Related CN1048122C (zh) | 1990-02-15 | 1991-02-13 | 开关电源 |
Country Status (12)
Country | Link |
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EP (1) | EP0515421B1 (zh) |
JP (1) | JP3155004B2 (zh) |
CN (1) | CN1048122C (zh) |
AT (1) | ATE121875T1 (zh) |
AU (1) | AU7215891A (zh) |
DE (2) | DE4004707A1 (zh) |
ES (1) | ES2073738T3 (zh) |
HK (1) | HK67996A (zh) |
MY (1) | MY105958A (zh) |
PT (1) | PT96763B (zh) |
TR (1) | TR24696A (zh) |
WO (1) | WO1991012649A1 (zh) |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
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DE19652604A1 (de) * | 1996-04-23 | 1997-10-30 | Thomson Brandt Gmbh | Netzteil für ein Gerät mit Standby-Betrieb |
CN1059988C (zh) * | 1998-08-20 | 2000-12-27 | 深圳市华为电气股份有限公司 | 高效率多路输出电源 |
DE10001866A1 (de) * | 2000-01-18 | 2001-08-02 | Infineon Technologies Ag | Verfahren zum Steuern eines Schaltnetzteiles sowie Schaltnetzteil |
JP4301763B2 (ja) | 2001-10-31 | 2009-07-22 | 藤倉化成株式会社 | 銀化合物ペースト |
AU2014218956B2 (en) | 2013-02-21 | 2016-07-07 | Siemens Aktiengesellschaft | Power supplies having multi-tap voltage attenuators and methods of power supply assembly |
CN107294506B (zh) * | 2016-03-30 | 2020-08-07 | 中芯国际集成电路制造(上海)有限公司 | 晶体振荡器电路 |
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US3564393A (en) * | 1969-03-12 | 1971-02-16 | North American Rockwell | Circuit using capacitor and switch on primary winding of transformer for regulating voltage on secondary winding of transformer |
CA1317369C (en) * | 1988-03-10 | 1993-05-04 | Giovanni Michele Leonardi | Switch-mode power supply |
JP2773195B2 (ja) * | 1988-04-05 | 1998-07-09 | 松下電器産業株式会社 | スイッチング電源装置 |
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1990
- 1990-02-15 DE DE4004707A patent/DE4004707A1/de not_active Withdrawn
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1991
- 1991-02-06 WO PCT/EP1991/000227 patent/WO1991012649A1/de active IP Right Grant
- 1991-02-06 JP JP50371591A patent/JP3155004B2/ja not_active Expired - Fee Related
- 1991-02-06 DE DE59105330T patent/DE59105330D1/de not_active Expired - Fee Related
- 1991-02-06 AU AU72158/91A patent/AU7215891A/en not_active Abandoned
- 1991-02-06 EP EP91903372A patent/EP0515421B1/de not_active Expired - Lifetime
- 1991-02-06 AT AT91903372T patent/ATE121875T1/de active
- 1991-02-06 ES ES91903372T patent/ES2073738T3/es not_active Expired - Lifetime
- 1991-02-12 MY MYPI91000232A patent/MY105958A/en unknown
- 1991-02-13 TR TR91/0093A patent/TR24696A/xx unknown
- 1991-02-13 CN CN91100910A patent/CN1048122C/zh not_active Expired - Fee Related
- 1991-02-14 PT PT96763A patent/PT96763B/pt not_active IP Right Cessation
-
1996
- 1996-04-18 HK HK67996A patent/HK67996A/xx not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
PT96763B (pt) | 1998-08-31 |
EP0515421A1 (de) | 1992-12-02 |
JPH05504251A (ja) | 1993-07-01 |
EP0515421B1 (de) | 1995-04-26 |
WO1991012649A1 (de) | 1991-08-22 |
DE59105330D1 (de) | 1995-06-01 |
MY105958A (en) | 1995-02-28 |
DE4004707A1 (de) | 1991-08-22 |
ATE121875T1 (de) | 1995-05-15 |
HK67996A (en) | 1996-04-26 |
ES2073738T3 (es) | 1995-08-16 |
JP3155004B2 (ja) | 2001-04-09 |
AU7215891A (en) | 1991-09-03 |
CN1055451A (zh) | 1991-10-16 |
PT96763A (pt) | 1992-11-30 |
TR24696A (tr) | 1992-03-01 |
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