Conference Paper

Instantaneous feedback control of a single-phase PWM inverter with nonlinear loads by sine wave tracking

Lab. d'Electrotech. et d'Electron. Ind., Inst. Nat. Polytech. de Toulouse
DOI: 10.1109/IECON.1989.69623 Conference: Industrial Electronics Society, 1989. IECON '89., 15th Annual Conference of IEEE
Source: IEEE Xplore

ABSTRACT The authors propose a novel method for the instantaneous digital
control of a PWM (pulse-width modulated) inverter used in an
uninterruptible power supply. The output voltage is compared to a
sinusoidal reference at each sampling instant to compute in real time
through a digital controller the pulse width of the same interval. The
closed-loop digital feedback eliminates the steady-state error of the
output voltage with a very short computation time. This strategy is
verified through computer simulations and provides a very fast
compensation of disturbances caused by nonlinear loads, such as
rectifiers and triac loads, with low total harmonic distortion and
fundamental control

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