Introduction to Three Phase Dual Converter Seminar Topic:
For power conversion from ac to dc in industries thyristor based three phase controlled rectifiers which offers a reliable conversion and have a long life time. These are mainly used for controlling the speed of the dc motor but the controlled rectifiers have a complex circuit. In this paper we will see the working of the three phase a dual converter which is mainly used in conversion in high power loads. We will see how the dual phase converter works and the advantages of it when compared to others converters.
Brief on the working of dual phase converter:
In the construction of a dual phase converter we find six transformers and three full wave bridge rectifiers and a firing circuit. In this converter the three phase power supply is supplied from the source and the converter converts into dc power and the dc power can be again converted into ac power. By using the firing circuit the angles are controlled such that the output voltages will have the same polarity.
The instantaneous voltages will be in out of phase due to which the voltage difference occurs and if the output currents are interconnected a large current flows between them but not through the load. By adjusting the firing angles the voltages drive the current due to which one converter converts it into dc current and the other gets converted and the other drives the same output current by which a bidirectional operation is performed.
Conclusions:
The three phase dual converters can also be used for performing four quadrant operations which is used for controlling the speed of the dc motor. This is achieved by changing the firing angles which causes a reverse operation. The dual converter is very easy to construct and does not have any complexity. In this there will be no voltage drop across in the switches and there will be no currents existing even in reverse bias voltage condition.
Download Electrical Seminar Report on Three Phase Dual Converter.