load test on dc compound generator (long shunt)

it is very useful for 2 d year electrical students,this ppt will explain in depth of experiment about dc compound generator.

1. WELCOME THIAGARAJAR COLLEGE OF ENGINEERING (A Govt. Aided, ISO 9001:2008 Certified, Autonomous Institution Affiliated to Anna University) MADURAI – 625 015 Department of Electrical and Electronics Engineering

2. LOAD TEST ON DC COMPOUND GENERATOR ( LONG SHUNT ) PRESENTED BY , V.Rajalakshmi -14E87 T.Naveena -14E80 R.Priyadharshini -14E85 T.Palani Kumar -14E83 S.P.Nandhini -14E79 P.Prakash -14E84 S.Priyanka -14E86 S.Padmanathan -14E82  

3. Dc compound generator Cumulatively Differential Long Shunt Short Shunt

4. CHARACTERISTICS

5. Aim: To conduct load test on DC compound generator (long shunt)and to determine its characteristics . Internal characteristics – generated emf Vs armature current External characteristics - terminal voltage Vs load current S NO APPARATUS SPECIFICATION QUANTITY 1 MC VOLTMETER (0-300V) 1 (0-10V) 2 2 MC AMMETER (0-50A) 1 (0-1A) 1 3 RHEOSTAT 910 Ω ,0.7 A 2 4 CARBON RHEOSTAT 50 Ω ,4.1A 1 5 LOAD (40A,160V) 1 APPARATUS REQUIRED:

6. NAME PLATE DETAILS: S NO PARAMETERS MOTOR GENERATOR 1 RATED VOLTAGE 230V 160V 2 RATED CURRENT 35.7A 38A 3 RATED SPEED 1450rpm 1450rpm 4 RATED POWER 7KW 6.1KW 5 RATED FIELD CURRENT 0.58A 0.58A FORMULAE USED: Eg = V + Ia (Ra+Rf), Ia =load current+ filed current Eg = generated emf Ia = armature current Ra = armature resistance Rf = series filed resistance

7. PROCEDURE: 1. Make the connections as shown in the figure 2. Keep the D.C motor field in minimum position and generator rheostat in maximum position initially load should not be connected to generator out put terminals and are open circuited. 3. Motor started with the help of a 3-point starter and its field regulator is adjusted so that rated speed of motor obtained 4. The gen field rheostat is also adjust such that the rated voltage is obtained at the gen terminals. 5. By keeping the gen field excitation constant load is switched on varied in steps and meters readings are tabulated. 6. In each step of load variation readings are taken the motor is running at rated speed is achieved by adjusting motor field rheostat variation of load in speed is continued till the generator supplies rated current. 7. When the current exceeds gen rated current decrease the load to zero and open the DPST

8. S NO FIELD CURRENT If(A) LOAD CURRENT IL(A) TERMI NAL VOLTAGE v ARMATURE CURRENT Ia(A) Eg= v+Ia (Ra+Rf) 1 0.35 160 0.35 160.049 2 0.21 1 94 1.21 94.17 3 0.17 2 76 2.17 76.30 4 0.15 3 68 3.15 68.44 5 0.13 4 60 4.13 60.58 6 0.11 5 52 5.11 52.71 LONG SHUNT DIFFERENTIAL COMPOUND

9. S NO FIELD CURRENT If(A) LOAD CURRENT IL(A) TERMI NAL VOLTAGE v ARMATURE CURRENT Ia(A) Eg= v+Ia (Ra+Rf) 1 0.35 174 0.35 174.049 2 0.36 5 175 5.36 175.75 3 0.37 8 177 8.37 178.17 4 0.38 11 179 11.38 180.59 5 0.39 14 182 14.39 184.02 6 0.40 17 186 17.40 188.44 LONG SHUINT CUMLATIVE COMPOUND

10. MEASUREMENT OF Ra: S NO Va Vf ARMATURE CURRENT (I) Ra= Va /I Rf=Vf/I 1 1.2 0.5 11 0.109 0.045 2 2.6 0.9 25 0.104 0.036 AVERAGE 0.1 0.0405

11. RESULT: By conducting load test the performance characteristics of DC compound generator were obtained.

12. Thank you