An assessment of a Square-Wave Series Voltage Compensator increasing Low Voltage Ride Through capability on industrial electronic loads

摘要

This paper addresses a study of Dynamic Voltage Restorers (DVRs) and Series Voltage Compensators (SVCs) applied to voltage surge protection and able to maintain the voltage on susceptible loads. The restorer is applied on industrial environments when reliability of drives and electronics systems is desired, avoiding stops by voltage surges and problems from electrical grid, such as voltage sags. It is estimated that power quality problems generate production losses and downtime in manufacturing process at industries, in consequence of sensible loads to voltage variation, simplified solutions will be presented for this concern. First, the conventional sinusoidal dynamic voltage restorer will be cited, and then, three simplified topologies will be discussed, with the proposal of a square-wave series voltage compensator (SW-SVC) able to compensate voltage sags with improved cost-efficiency. The design includes a description of the inherent system parts, such as the coupling transformer, harmonic filter at the output of the static power converter, the converter configuration and its semiconductors, the input rectifier, grid synchronization system. Then will be discussed the performance analysis mitigating voltage sags, increasing Low Voltage Ride Through (LVRT) of electronic loads and improving industrial power quality.