半桥逆变电路分析与设计

1、 开发设计半桥逆变电路分析与设计刘强远 牛俊邦(东营 石油大学 刘强远 , 牛俊邦 . 半桥逆变电路分析与设计 . 石油仪器 ,1999,13(1 ,2324摘 要 半桥逆变电路具有开关器件少 、 控制性能好的特点 , 可作为各种电子仪器设备供电电源的主电路 。文 章提出了一种该电路主要参数的设计计算方法并给出了计算实例 。 主 题 词 开关 电源 电位差计 电路 半桥式 逆变作者介绍 刘强远 工程师 ,1962年出生 ,1987年毕业于石油大学自动化系自动化专业 , 现在石油大学仪器仪表研 究所从事仪器仪表的研制开发工作 , 主要研究方向为大功率电源的开发与应用 。 邮编 :257062电路

2、简介脉宽调制型半桥逆变电路 , 作为电子仪器电源 的主电路形式之一得到广泛应用 。 其结构形式如图 1所示 。 在图 1(a 中 E 为一直流恒电源 , 通常由电 网 电压经全桥整流滤波获得 ; S 1、 S 2 为大功率的场图 1 半桥电路原理图(a 常用电路 (b 等效电路效应管或 IG BT 器件 ; C 1、 C 2为换流电容 。若把 S 1、 S 2视为理想开关并引入理想变压器模型 , 图 1(a 可 简化成图 1(b 1, 且有R =(N 22R f =K 2R f (1式中 , N 1、 N 2为主变压器 B 的初级 、 次级匝数 , K 为变压器的变比 , R f 为输出负载电

3、阻 , R 为等效负载电阻 。 电路分析 2在图 1(b 中 ,S 1闭合时 C 1放电 、 C 2充电 , S 2闭 合时 C 2放电 、 C 1充电 。若 S 1闭合视为正半波 , 则 S 2闭合为负半波 。 对于消耗在 R 上的有功功率 , 正 负半波皆可等效为一个图 2所示 RC 电路的零输入 响应 , 其中C =C 1+C 1(2 图 2 简化等效电路 图 2中 , 正半波时的 U C 即为图 1(b 中的 U C 1, S即为 S 1; 同理 , 负半波时 U C 为 U C 2, S 为 S 2。若设 C 上的电压初始值U Ct =0=U M(3图 1(b 中的 S 1闭合后 ,

4、 若设最大脉宽为 t on , 依据图 2及文献 2便可求得 U C 1U C 1=U C =U M e-RC 0 t t on (4从式 (4 中可求出U C 1t =t on=U M e-tRC(532 第 13卷 第 1期 石 油 仪 器 再依据图 1(b 、 式 (5 可求得U C 2 t =t on =E -U C 1t =ton=E -U M e -tRC (6一个周期后 , 电路回到 t =0时的初始状态 , 因此可 把式 (6 与式 (3 合并 , 即有E -U M e - tRC =U M (7从式 (7 中可求出 U MU M = 1-e - tRC(8若 RC µ

5、;t on , U M 又可表示为U M =2(9 由此可见 , 当电路的时间常数 RC µt on 时 , C 1、 C 2两端的电压值皆恒定为2。 则电路在一个周期内消耗 在 R 上的有功功率的平均值 P 可表示为P = ( 2R t on +t d=24R t on +t d(10式中 t d 为死区时间 。计算实例文献 3中场效应管逆变式恒电位仪 , 电源电压 为单相交流 220V 。 最大脉宽 t on =17×10-6s , 死区 时间 t d =3×10-6s 。额定输出电压 U =30V , 额定 工作电流 I =125A 。 试求出主电路参数 。

6、解 :恒电位仪的额定输出功率P e =IU =125×30=3750W若设额定工作状态下的效率 =80%, 则实际 输出功率 P 应为P = P=0. 8=4687. 5W输出负载电阻 R f 应为R f =I 2=1252=0. 3考虑到电网电压的波动 , 单相交流经全桥整流 滤波后的直流电压 E 取值为 1E =260V依据式 (10 可求出 RR =24P t on +t d=24×4687. 5-617×10-6+3×10-6 =3. 06式 (9 成立的条件为 RC µt on , 实际设计中取 RC >5t on 便可满足要求

7、 , 即有C >R=-63. 06=27×10-6F 变比 K 依据式 (1 求出K =NN 2=f=0. 3=3. 19文献 3为了保证输出电压 U 30V , K =2. 9取值偏低 , 留有余量 。 试验结果表明 , 直接采用本文 的计算值便可 。参 考 文 献1 徐德高 , 金 刚 . 脉宽调制变换器型稳压电源 . 科学出版 社 ,19832 秦曾煌 . 电工学 (上册 . 高等教育出版社 ,19903 牛俊邦 , 刘强远 . H DY 125型场效应管逆变式恒电位仪 的研制 . 石油仪器 ,1997,11(6(收稿日期 :1998-07-27 编辑 :陈阿乾 AB S

8、TRACTSZhou G uangjia. The application and progress of GC in oil 2gas geological exploration and development. PI, 1999,13(1 :17As one of analytical instruments , G C is widely used in oil 2gas geological exploration and development. It has be 2 come a necesary instrament for the com ponent analysis o

9、f rock organism , the research of oil and gas in basin the evalua 2 tion of oil 2gas showing in well site and chemical exploration on the surface. Als o , a great many applications and paractice prom otes the im provement and innovation to G C instrument. The advance and im provements to many kinds

10、of sam ple inlet system form new instruments and nethods for oil 2gas exploration.Subject Words :gas chromatography , analyzer , oil and gas res ource , oil and gas show , oil field development , geochemi 2 cal explorationMa G uangyan. R ecent advences of native core 2flowing tester. PI,1999,13(1 :8

11、9,16The comm on constructions and functions of native core 2flowing tester are described. The error 2detecting of HC -200 m odel equipment is 2. 581×10-1to water , 8. 455×10-2to RF of polymer , and 7. 682×10-3to RRF of polymer. The developping derection of the equipment is pointed. .S

12、ubject Words :core , fluid , analyzer , evaluation , percolation parameter , domesticChai Shuchang. Seismic data acquisition and instrument evolution. PI,1999,13(1 :1016The paper analyzes the current technical situation about seismic data acquisition , and points out that main factors re 2 stricted

13、of data acquisition are as the results of the tw o links of emitting and receipting , but not due to instrument. C om 2 paring with the biological ev olutionism , the paper presents the tortuous course of instrument development. And points out em phatically that the key technical element affecting t

14、he record precision should be distortion. Here distortion and dynam 2 ic range are synonym. In the times of using 24bits 2A/D instrumnet , analogue channel must be sim plified. Besides a am plifier , needn t add any analogue circuit. I f use any analogue circuit , such as high/low filter , that will

15、 reduce the dynamic range but not increase. The paper points out further that g oing through a series of ev olution , seismic instrument structure has begin to trend a sim ple m odel that consist of com puter plus com puter netw ork data transmission. The m odel provides a g ood opportunity of devel

16、oping national instrument products. And let us see the hope of success in manu factur 2 ing ten thousand channels instrument.Subject Words :seismic explorotion , data acquisition , high res olution , seism ometer , developing trend , A/D converter Xu H ongzhe , Chen Jiner and W ang Xiaoping. Applica

17、tion and development of Softw are Digital Filtering Sys 2 tem. PI,1999,13(1 :1719S oftware Digital Filtering System (S DFS includes the data aquisition and digital fitering. The data aquisition of this system mainly s olves the problem of data s ource. This paper intruduces the designation of S DFS

18、and focuse on discussing the method of data aquisition. The data aquisition in S DFS utilises the data aquisition elements to get data from extemal environment and puts them into mem ory through the serisl port , the data is als o processed to s ome extent , then it uses s ofware digtal filtering de

19、vice to filter and output the data. This method of data aquisition makes use of the inset of inline assemble language in high 2level language , as a result , the speed of data aquisition is heighented and the utility of this system is enhanced.Subject Words :digital filtering , data acquisition , sy

20、stem , env oronment , application , s oftwareW ang Shuxia. The research on testing system for shale shaker. PI,1999,13(1 :2022In the course of drilling in oil and gas industry , drilling fluid shaker is em ployed to rem ove harm ful s olid from drilling fluid. According to international standard , i

21、n the case of delivered products , dynamics test must be done to as 2 sure manu facturing quality of drilling fluid shaker. A fter checked , qualified products is permitted to leave factory. Drilling fluid shaker dynamics testing system developed and produced by DaG ang oil field can check the following items : vertical acceleration of deck , horizontal acceleration of deck , am plitude of vibration , inherent frequency of shaker 2b