A Design Approach of Discrete-Time Resonant Controllers for UPS Applications through Frequency Response Analysis

ROBERTO CARBALLO; FERNANDO BOTTERON; GERMÁN G. OGGIER; GUILLERMO O. GARCÍA

IET Power Electronics

IET

Año: 2016

A new methodology to design discrete time multiple resonant controllers for single-phase UPS inverters is proposedin this paper. This methodology is based on classical linear tools and consists on the synthesis of the inverter output impedanceaccording to standard specifications. The inverter output impedance is synthesized using a proportional controller in the innercurrent control loop and a multiple resonant controller in the outer voltage control loop. A prototype was built to demonstratethe practical feasibility of the theoretical proposal. A significant reduction of the harmonic impedance at determined harmonicfrequencies results in a low THDv of the output voltage of about 1.76%, for IEC 62040-3 normalized load.