Application of high power rectifiers with low harmonics and high power factor

Rectifiers, the most commonly used converter type among power electronics converters, are widely used for DC power supplies, battery chargers, motor control, electro-chemical process, dc arc furnaces, and many other applications. In the rectifier, which is known as line commutated converter, thyristors are preferred as semiconductor power switches. Thyristor has the highest current and voltage capacity between power semiconductor switches. In rectifiers, thyristors are preferred to the other semiconductor switches especially at high power levels due to their high reliability and relatively low costs. In rectifiers, reactive power increases with delay angle. Besides, total harmonic distortion of the input current (THDi) is very high. Decreasing THDi value is very important to comply with IEEE-519 standards and IEC-61000-3-2, and for energy quality issues. In this study, to conform to international standards, these standards were examined and were carried out on the rectifier system. Studies in the literature, rectifiers was analyzed theoretically and simulated. Rectifiers have examined the characteristics of the different working conditions. The application part of this thesis, a low harmonic and high power factor 110V/400A rectifier which has low THDi and good power factor was developed. The developed rectifier will be used for battery charging purposes, but also it could be adopted to the applications such as electroplating rectifiers, dc power source etc. by software modification. In the developed rectifier, THDi value will be lower than 5%, and power factor value will be higher than 0.95. At the end of the thesis, it is aimed to make contribution to literature and to the national technology on high power rectifiers.