實驗八、交流電橋,,,,,,,,,,

,,,學(xué)號：,,,姓名：,,,,

[數(shù)據(jù)記錄]實驗桌號NO：,,,,,,,,,,

表8-1所用電阻箱各倍率檔的準確度等級,,,,,,,,,,

10×,,10000,1000,100,10,1,0.1,,,

aR,,0.1,0.1,0.1,0.2,1,2,,,

表8-2所用電容箱各倍率檔的準確度等級,,,,,,,,,,

10×,,0.1,0.01,0.001,0.0001,本實驗所用電感箱10mH檔準確度等級,,,,

aC,,0.5,0.65,2,5,aL,0.5,,,

一、利用電容比較電橋測電容,,,,,,,,,,

待測電容容量估計值CX≈,,,0.47,取工作電源電壓值：US=,,,10,頻率：f=,1000,

表8-3電容箱起始電容值C10+C20=,,,,,注：表中C`2為電容箱讀數(shù)盤的示值，C2=C`2+(C10+C20),,,,,

n,R4(Ω),R3(Ω),R2(Ω),C`2(μF),C2(μF),δC2(μF),平衡時毫伏表示值（mV）,CX(μF),RX(Ω),

1,1000.0,1000.0,,,0,,,0,0,

2,100.0,100.0,,,0,,,0,0,

3,100.0,1000.0,,,0,,,0,0,

CX=(R3/R4)×C2RX=(R4/R3)×R2,,,,,,,,,,

二、利用西林電橋測量,,,,,,,,,,

待測電容同上，,,,,同樣取工作電源電壓值：US=,,,10,頻率：f=,1000,

表8-4電容箱C3起始電容值C10+C20=,,,,,0,電容箱C4起始電容值C10+C20=,,,0,

R2(Ω),,R3(Ω),C`3(μF),C3(μF),C`4(μF),C4(μF),平衡時毫伏表示值（mV）,CX(μA),RX(Ω),

200.0,,198.3,0.002,0.002,0.5000,0.5,4.32,0.49575,0.8000,

CX=(R3/R2)×C4RX=(C3/C4)×R2,,,,,,,,,,

三、利用可調(diào)電感比較電橋測量電感,,,,,,,,,,

待測電感量估計值LX≈,,,33,取工作電源電壓值：US=,,,10,頻率：f=,1000,

表8-5電感箱10mH線圈直流電阻值為R2=,,,,,,,,,3.87,

R4(Ω),,R3(Ω),R`(Ω),,δR4(Ω),平衡時毫表示值（mV）,,,RX(Ω),

400.0,,100.0,30,10.00,0.1,63.9,,40.00,135.5,

LX=(R4/R3)×L2RX=(R4/R3)×(R2+R′),,,,,,,,,,

四、利用麥克斯韋電橋測量,,,,,,,,,,

"待測電感同上,取工作電源電壓值：US=",,,,,10,頻率：f=,1000,,,

表8-5【下表中LX=R4R2C3、RX=(R4/R3)×R2。】電容箱C4起始電容值C10+C20=,,,,,,,,,,

R2(Ω),,R3(Ω),R4(Ω),C`3(μF),C3(μF),平衡時毫表示值（mV）,,LX(mH),RX(Ω),

100.0,,,400.0,,0,,,0.000,#DIV/0!,

[數(shù)據(jù)處理],,,,,,,,,,

一、待測電容的損耗,,,,,,,,,,

1.電容比較電橋測量,,,,,,,,,,

n,R4(Ω),R3(Ω),R2(Ω),,C`2(μF),,tgδ(＝2πfR2C2),,,

1,1000.0,1000.0,0,,0,,0.00000,,,

2,100.0,100.0,0,,0,,0.00000,,,

3,100.0,1000.0,0,,0,,0.00000,,,

2.西林電橋測量:tgδ=2πfR3C3=,,,,,0.00249,,,,,

二、待測電感的損耗,,,,,,,,,,

1.可調(diào)電感比較電橋測量：Q＝Lω/RL=2πfLX/RX=,,,,,,,1.8551,,,

2.麥克斯韋電橋測量：Q＝Lω/RL=2πfLX/RX=2πfR3C3=,,,,,,,,0.000,,

三、電容比較電橋測量不確定度的估算,,,,,,,,,,

1.電橋靈敏度限制而使電容測量值引入的B類標準不確定度:,,,,,,,,,,

R4=,,1000.0,R3=,1000.0,,,,0.0000000,,

R4=,,100.0,R3=,100.0,,,,0.0000000,,

R4=,,100.0,R3=,1000.0,,,,0.000000,,

2.電容箱的極限誤差引入的B類標準不確定度:,,,,,,,,,,

C2=,,0,,,,0.00000,,,0.00000,

C2=,,0,,,,0.00000,,,0.00000,

C2=,,0,,,,0.000000,,,0.00000,

3.電阻箱的極限誤差引入的B類標準不確定度:,,,,,,,,,,

R3誤差引入的B類不確定度,,,R3=,1000.0,,,,0.577,,

,,,R3=,100.0,,,,0.075,,

,,,R3=,1000.0,,,,0.577,,

R4誤差引入的B類不確定度,,,R4=,1000.0,,,,0.577,,

,,,R4=,100.0,,,,0.075,,

,,,R4=,100.0,,,,0.075,,

橋臂電阻、電容值誤差引入的電容測量值的合成B類標準不確定度：,,,,,,,,,,

,1000.0,R3=,1000.0,,,,,,#DIV/0!,

,100.0,R3=,100.0,,,,,,#DIV/0!,

,100.0,R3=,1000.0,,,,,,#DIV/0!,

∴電容比較電橋測量的合成不確定度分別為：,,,,,,,,,,

ⅰ.R4=,,1000.0,R3=,1000.0,,,,#DIV/0!,,

ⅱ.R4=,,100.0,R3=,100.0,,,,#DIV/0!,,

ⅲ.R4=,,100.0,R3=,1000.0,,,,#DIV/0!,,

二、電感比較電橋測量不確定度的估算,,,,,,,,,,

1.電橋靈敏度限制而引入的B類標準不確定度:,,,,,,,,,,

,,,,0.006,,,,,,

2.電感箱的誤差而引入的B類標準不確定度:,,,,,,,,,,

,,,,,0.0289,,,,,

3.電阻箱的誤差而引入的B類標準不確定度:,,,,,,,,,,

,,,,0.0751,、,,,0.248,,

橋臂電阻、電感誤差引入的合成B類標準不確定度為：,,,,,,,,,,

＝,,,,,,0.1219,,,,

∴電感比較電橋測量的合成不確定度為：,,,,,,,,,,

=,,,,0.122,,,,,,

[結(jié)果報道],,,,,,,,,,

一、電容比較電橋測得待測電容量及其損耗如下：,,,,,,,,,,相對不確定度

R4=,,1000.0,R3=,1000.0,,,0.0000,#DIV/0!,,#DIV/0!

,,,,,,0.0000,,,,

R4=,,100.0,R3=,100.0,,,0.0000,#DIV/0!,,#DIV/0!

,,,,,,0.0000,,,,

R4=,,100.0,R3=,1000.0,,,0.000,#DIV/0!,,#DIV/0!

,,,,,,0.0000,,,,

二、利用西林電橋測得該電容量及其損耗為：,,,,,,,,,,

,CX=,0.4958,,,0.002492,,,,,

三、用可調(diào)電感比較電橋測得待測電感的電感量及其品質(zhì)因素為：,,,,,,,,,,

,,,40.00,0.13,,,1.855,,,0.31%

四、用麥克斯韋電橋測得待測電感的電感量及其品質(zhì)因素為：,,,,,,,,,,

,,0.00,,,,,0.000,,,

[結(jié)果討論],,,,,,,,,,

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