1. Harmonic Reduction in the Utility Interface SCR RectifierBy
Turki al saleh
Under Supervision of
Dr. Ali M. Eltamaly

2. :Abstract
Improved approach to reduce harmonics in the three-phase controlled rectifier is presented.
The injection current path uses zigzag transformer and boost converter to control the injection current.
Complete implementation of boost converter
Experimental results have been used to verify the mathematical and simulation results.

3. Harmonics:
harmonics can be defined as a sinusoidal component having frequencies that are an integral multiple of the fundamental frequency.

4. Harmonic Reduction in the three-phase controlled rectifier

5. Harmonic Reduction by Using R-L in Injection Path

6. Experimental Results I V

7. Simulation Results

8. Harmonic Reduction by Using Boost Converter

9. Implementation of Boost Converter
Boost Consist:-
1- Control Circuit:
DC Power Supply.
Voltage Controlled Saw-tooth Oscillator and Comparator.
2- Isolation Circuit
3- Power Circuit

10. The Component Required for Power Supply:
Transformer 220/
Two Regulator 7815 & 7915
Two capacitors 100uF & two capacitors 10uF
Bridge diode

11. The Power Supply Module

13. Voltage Controlled Saw-tooth Circuit Components:-
PUT 2n6027
Two OP-amp 741
Diode
Capacitor 10nF
Two Potentiometer 100k
Resistors

14. Voltage Controlled Saw-tooth Oscillator and Comparator Circuit:-

16. Isolating Circuit Components:-
Transformer 220/
Optocoupler 4N32
Regulator 7815
Two capacitors 10uF
Bridge diode

17. Isolating Circuit Module

19. 2- Power Circuit Component:-
Transformer
Inductance
MOSFET
Capacitor 470uF(250V)
High current diode
bridge diode

20. Power Circuit of Boost Converter

23. Control Circuit
Isolating
Circuit
Power
Circuit

24. BOOST

27. The Input & Output of Control Bridge
Experimental Results:
The Input & Output of Control Bridge

28. The Output of Voltage Regulators 7815 and 7915

29. The Saw-tooth Waveform and Control Pulse

30. The Input & Output of Pulse

31. I V

33. I V

35. Vdn V

37. Vfn V

39. Conclusions: We got low THD with no power losses.
The wave form after reinjection is very near to sinusoidal.
Experimental results agrees with simulation results.