A NEW PROPOSED DESIGN FOR CAPACITANCE MEASURING BRIDGE

All of the capacitance practical applications require precision measurements of capacitance.

To increase calibration accuracy of capacitance, consideration of the accuracy limitations is

composed by the connection errors and parasitic capacitances. Transformer – ratio arms

bridge is used extensively in the accurate and precise measurements of many types and sizes

of capacitances. Hence, they have many advantages over other measurement devices.

The basic circuit of transformer-ratio bridge is demonstrated and its main measurement errors

are investigated to be avoided or reduced. A new design of transformer-ratio capacitance

bridge is proposed to decrease the bridge errors to minimum values. This new bridge design is

based on a fixed number of secondary turns in the standard arm of the bridge. It is balanced

with the unknown capacitance by variable standard decades capacitances. This new design

improves accuracy and precision of capacitance measurements that carried out by this bridge.

Advantages and disadvantages of our new capacitance bridge design are studied and a future

work is recommended.