08.实验八、-交流电桥

实验八、交流电桥,,,,,,,,,,

,,,学号：,,,姓名：,,,,

[数据记录]实验桌号NO：,,,,,,,,,,

表8-1所用电阻箱各倍率档的准确度等级,,,,,,,,,,

10×,,10000,1000,100,10,1,0.1,,,

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

表8-2所用电容箱各倍率档的准确度等级,,,,,,,,,,

10×,,0.1,0.01,0.001,0.0001,本实验所用电感箱10mH档准确度等级,,,,

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

一、利用电容比较电桥测电容,,,,,,,,,,

待测电容容量估计值CX≈,,,0.47,取工作电源电压值：US=,,,10,频率：f=,1000,

表8-3电容箱起始电容值C10+C20=,,,,,注：表中C`2为电容箱读数盘的示值，C2=C`2+(C10+C20),,,,,

n,R4(Ω),R3(Ω),R2(Ω),C`2(μF),C2(μF),δC2(μF),平衡时毫伏表示值（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、利用西林电桥测量,,,,,,,,,,

待测电容同上，,,,,同样取工作电源电压值：US=,,,10,频率：f=,1000,

表8-4电容箱C3起始电容值C10+C20=,,,,,0,电容箱C4起始电容值C10+C20=,,,0,

R2(Ω),,R3(Ω),C`3(μF),C3(μF),C`4(μF),C4(μF),平衡时毫伏表示值（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、利用可调电感比较电桥测量电感,,,,,,,,,,

待测电感量估计值LX≈,,,33,取工作电源电压值：US=,,,10,频率：f=,1000,

表8-5电感箱10mH线圈直流电阻值为R2=,,,,,,,,,3.87,

R4(Ω),,R3(Ω),R`(Ω),,δR4(Ω),平衡时毫表示值（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、利用麦克斯韦电桥测量,,,,,,,,,,

"待测电感同上,取工作电源电压值：US=",,,,,10,频率：f=,1000,,,

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

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

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

[数据处理],,,,,,,,,,

一、待测电容的损耗,,,,,,,,,,

1.电容比较电桥测量,,,,,,,,,,

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.西林电桥测量:tgδ=2πfR3C3=,,,,,0.00249,,,,,

二、待测电感的损耗,,,,,,,,,,

1.可调电感比较电桥测量：Q＝Lω/RL=2πfLX/RX=,,,,,,,1.8551,,,

2.麦克斯韦电桥测量：Q＝Lω/RL=2πfLX/RX=2πfR3C3=,,,,,,,,0.000,,

三、电容比较电桥测量不确定度的估算,,,,,,,,,,

1.电桥灵敏度限制而使电容测量值引入的B类标准不确定度:,,,,,,,,,,

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.电容箱的极限误差引入的B类标准不确定度:,,,,,,,,,,

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

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

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

3.电阻箱的极限误差引入的B类标准不确定度:,,,,,,,,,,

R3误差引入的B类不确定度,,,R3=,1000.0,,,,0.577,,

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

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

R4误差引入的B类不确定度,,,R4=,1000.0,,,,0.577,,

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

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

桥臂电阻、电容值误差引入的电容测量值的合成B类标准不确定度：,,,,,,,,,,

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

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

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

∴电容比较电桥测量的合成不确定度分别为：,,,,,,,,,,

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、电感比较电桥测量不确定度的估算,,,,,,,,,,

1.电桥灵敏度限制而引入的B类标准不确定度:,,,,,,,,,,

,,,,0.006,,,,,,

2.电感箱的误差而引入的B类标准不确定度:,,,,,,,,,,

,,,,,0.0289,,,,,

3.电阻箱的误差而引入的B类标准不确定度:,,,,,,,,,,

,,,,0.0751,、,,,0.248,,

桥臂电阻、电感误差引入的合成B类标准不确定度为：,,,,,,,,,,

＝,,,,,,0.1219,,,,

∴电感比较电桥测量的合成不确定度为：,,,,,,,,,,

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

[结果报道],,,,,,,,,,

一、电容比较电桥测得待测电容量及其损耗如下：,,,,,,,,,,相对不确定度

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、利用西林电桥测得该电容量及其损耗为：,,,,,,,,,,

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

三、用可调电感比较电桥测得待测电感的电感量及其品质因素为：,,,,,,,,,,

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

四、用麦克斯韦电桥测得待测电感的电感量及其品质因素为：,,,,,,,,,,

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

[结果讨论],,,,,,,,,,

——提示：