Title :
Decoupled control of a 4-leg inverter via a new 4×4 transformation matrix
Author :
Ryan, Michael J. ; De Doncker, Rik W. ; Lorenz, Robert D.
Author_Institution :
GE Corp. Res. & Dev., Niskayuna, NY, USA
Abstract :
Four-leg (3-phase 4-wire) inverters are developed to power unbalanced/nonlinear three-phase loads. A unique 4×4 decoupling transformation matrix is used that enables direct transformation between the four degree-of-freedom (DOF) leg-modulation space of the inverter and its corresponding 3-DOF output-voltage v space. This is analogous to the well-known 3×3 “abc-qd” transformation developed for the 3-leg inverter. Details of this new 4×4 “Quad” transform are provided, along with a depiction of the voltage-vectors produced. Advanced synchronous-frame control techniques are applied with this 4-to-3 “abcn-qdo” transform to create a UPS-style inverter with sinewave output. Experimental results for an 8.6 kV a prototype inverter are presented
Keywords :
digital control; invertors; load (electric); voltage control; 3-phase 4-wire inverters; 4×4 Quad transform; 4×4 decoupling transformation matrix; 4×4 transformation matrix; 4-leg inverter; 4-to-3 abcn-qdo transform; 8.6 kV; UPS-style inverter; decoupled control; digital controller; four degree-of-freedom leg-modulation space; nonlinear three-phase loads; sinewave output; synchronous-frame control techniques; unbalanced three-phase loads; voltage control; voltage-vectors; Circuit testing; Circuit topology; Drives; Leg; Phase modulation; Power control; Power electronics; Power engineering and energy; Pulse width modulation inverters; Voltage control;
Conference_Titel :
Power Electronics Specialists Conference, 1999. PESC 99. 30th Annual IEEE
Conference_Location :
Charleston, SC
Print_ISBN :
0-7803-5421-4
DOI :
10.1109/PESC.1999.789001
