Development of a Smart Static Transfer Switch Based on a Triac Semiconductor for AC Power Switching Control

Abstract

Power system disruptions can be categorized as issues with the quality of electricity brought on by voltage sags, lightning strikes, and other system-related interferences. The static transfer switch (STS) has recently emerged as the most important technology for electric power transmission, distribution, and control systems to manage power supply during power system disruption issues, particularly in cost-effectively supplying power to critical loads and sensitive loads without interruption. In this paper, for the switching between the two AC sources during the voltage disruptions issue with low transfer time, a smart static transfer switch (SSTS) based on a digital switching algorithm and Triac semiconductor switch is proposed and experimentally tested. A digital switching algorithm based on online AC voltage sensing and zero-crossing detection is proposed and implemented inside a DSP MCU. The printed circuit board (PCB) of the proposed SSTS is designed and manufactured for the experimental performance investigation with different AC input voltage conditions. A comparative study based on the advantages and disadvantages of the proposed SSTS system with the previous works is also presented. A smart static transfer switch with a transition time of less than one cycle and a digital protection technique during fault conditions is obtained in this work.

Synchronous switching of uncompensated transmission line, by considering the effect of coupling voltage between the phases, trapped charge and the characteristics of CB

“…If the ZVC instant (corresponding to T_ZVC) is assumed to be zero, the time corresponding to point C is equal to TD_com. The equations of lines L1 and L2 are in (7), where K is equal to RDDS_pu and determined by the manufacturer (t A and t B are the moments corresponding to points A and B).…”

“…The advantage of controlled switching is that it reduces inrush current and mitigates over-voltages when operating the CB for switching different electrical equipment. Controlled switching is already used for enhancing the switching performance of major power system components such as transmission lines, transformer/reactors, and capacitor bank energization and de-energization [1][2][3][4][5][6][7].…”

Design and Implementation of Electronic Illumination Control System

“…The percent of power saving (δ%) is defined as: -74-Now concerning TRIAC, which is a semiconductor power device [9], it has four layers -76-…”