Instrumentation presentation by engineering .pptx

instrumentation presentation for the linear variable differential transducer.

1. Measurement of displacement using Lvdt Government Engineering College , Bilaspur Presented To: Asst. Prof. Malka Taranum Department of Electrical Engineering Government Engineering College, Bilaspur (C.G.) Presented By: Pinky Kunjam Roll No: 3007024 21030 Electrical Engineering

2. Linear Variable Differential Transformer Principle of Working The LVDT works under the principle of mutual inductance effect. It is also an electromechanical-based inductive transducer that converts rectilinear movement into an electrical signal.

3. Construction LVDT consists of one primary winding P, two secondary windings(S1& S2) and a soft iron core. The construction of LVDT is shown in below figure. The secondary windings are arranged on a cylindrical former with a movable soft iron core. The primary winding is surrounded by two identical secondary windings (S 1  and S 2 ), each of which has an equal number of turns. The secondary windings are connected in a series opposition.

4. The soft iron core arm is connected to the part to which the displacement is to be measured. This iron cores are subjected to hydrogen annealing in order to reduce harmonics, the residual voltage of the core, and to increase sensitivity.

5. Working A source of constant amplitude AC power, energize the primary winding, P, of the LVDT. The core then connects the nearby secondary windings S 1  and S 2 , the magnetic flux is created. According to the position of the core, the working of LVDT can be divided into 3 cases.

6. Case 1:- LVDT Core is in null Position: When the core of LVDT is in null position, the flux linking between both the secondary coils are same, hence voltage induced in secondary side is also equal. Hence net output voltage is V0= V1-V2=0 Case 2:-LVDT Core is moved left of null position. When the core of LVDT core is moved to left, then more flux links with coil S1 than S2. Hence voltage induced in S1 is greater than S2. The net output voltage is V0=V1-V2 is positive. Case 3:- LVDT Core is moved Right of null position. When the core of LVDT core is moved to right, then more flux links with coil S2 than S1. Hence voltage induced in S2 is greater than S1. The net output voltage is V0=V1-V2 i s negative.

7. Advantages oF LvDT LVDT has a low power consumption
It has a higher sensitive
It has a ruggedness
Easy to align and maintain
It has a wide range
It has a lower hysteresis loss
It has a higher measurement range

8. Disadvantage Of Lvdt Sensitive to a stray magnetic field
It has large primary voltage produce distortion in an output
Temperature affects the performance
It has limited dynamic response
Vibration due to displacement can affect the performance of the LVDT device
Large displacement is needed for small output

9. Thank you!