Output voltage control of a four-leg inverter based three-phase UPS by means of stationary frame resonant filter banks

Demirkutlu E., Cetinkaya S., HAVA A. M.

IEEE International Electric Machines and Drives Conference (IEMDC 2007), Antalya, Turkey, 3 - 05 May 2007, pp.880-881 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.1109/iemdc.2007.382785
  • City: Antalya
  • Country: Turkey
  • Page Numbers: pp.880-881
  • Keywords: four-leg, inverter, UPS, voltage regulation, unbalance, zero-sequence, harmonic, THD, crest factor, resonant filter, active damping, scalar PWM, zero-state partitioning, switching loss, efficiency
  • Middle East Technical University Affiliated: Yes


A method for high performance output voltage control of a four-leg inverter (FLI) based three-phase UPS is proposed. Stationary frame resonant filter bank based output voltage control loop, which is complemented by capacitor current feedback based active damping loop, is employed. Utilizing the zero-state partitioning variable, a generalized form of scalar PWM for the FLI is developed and the minimum loss discontinuous PWM method is derived. The controller and modulator design and implementation details for the FLI-UPS are given. Linear and nonlinear loads for balanced and unbalanced load operating conditions are considered. The scalar control and PWM methods are proven by means of theory, simulations, and experiments.