ABSTRACT
Bridge is used to convert the a series of circuit parameter such as resistance, capacitance and inductance into voltage or current output of the measurement circuit, the bridge circuit is widely used in modern detection technology.
Bridge can be divided into Balanced Bridge and Unbalanced Bridge.Unbalanced Bridge often with the use of some sensor. Some of the sensing element by the external environment (pressure, temperature, light intensity, etc.)caused by the change of its resistance changes. Resistance through the Unbalanced Bridge can be converted into a voltage output,then it can be achieved observation, measurement and control of the environmental change. Unbalanced Bridge has been widely used in the engineering survey. User can have different bridge in use,research found that exchange the location of the two sensing elemen,the result is obviously different.
This paper introduces the operation principle of the bridge and the use of the sensor such as resistance, capacitance and inductance.We analysis the sensitivity of the a.c unbalanced bridge based on the different bridge of the a.c unbalanced bridge, and based on the theoretical results, then we will give out the method of solving the problem.