Analysis and modeling of Class A, D and E phase shift transformers with the aim of improving power quality and stability limits

Subject Areas : Electronics Engineering

Hani shahnazari ¹ , Hadi Shahnazarisani ²

1 - Islamic Azad University, Science and Research Guilan Branch , Guilan , Iran
2 - Semnan University, Semnan, Iran

Received: 2021-04-27 Accepted : 2021-04-27 Published : 2019-07-23

Keywords:

Abstract :

Phase shifting transformers are used to control the power transmitted through the lines by changing the amplitude and phase angle of the voltage. In the first group, mechanical switches and moving parts are used in PST types, and in the second group, semiconductor switches and electronic power converters have replaced mechanical switches. In this article, the analysis of internal structure and performance of Class A, D and E phase shift transformers is expressed and using a program, power distribution in the power grid in two modes of use of phase shift transformers and without these transformers in soft The MATLAB software is simulated and the numerical results of the effect of phase shift transformers on current and power distribution between two 110KV parallel lines are investigated. It turns out that phase shifting transformers are used to control the distribution of active power between lines, and in Class A phase shifting transformers, the upper and lower limits of the thyristor fire angle are a function of the operating conditions of the power system and the limiting determinant. The performance of these transformers is the high harmonic content of the output voltage. In Class D, GTO switches are used and their switching on and off is forced by switching method, and one of their outstanding features is that the converters do not depend on the operating conditions of the system, whose output can be controlled continuously and in all conditions.