A Three-Phase Four-Wire Inverter Control Technique
for a Single Distributed Generation Unit in Island Mode
Min Dai, M.N. Marwali, Jin-Woo Jung and A. Keyhani
Ohio State Univ, Columbus, OH, USA ;
This paper appears in : IEEE Transactions on
Power Electronics
Date: January 2008
Abstract:
A control technique is developed
for a three-phase four-wire split dc bus inverter of a single distributed
generation unit working in island mode. The control technique combines an inner
discrete-time sliding mode controlled (DSMC) current loop and an outer robust
servomechanism controlled voltage loop. The control algorithms are developed
under stationary (Clarke's) reference frame and a modified space vector pulse
width modulation (MSVPWM) is proposed to implement the algorithm under Clarke's
reference frame. The proposed technique achieves voltage regulation with low
steady state error and low total harmonic distortion and fast transient response
under various load disturbances. Meanwhile the usage of MSVPWM in a
stationary reference frame yields better transient performance under limited dc
bus voltage compared to conventional uniformly sampled sine wave modulation in
ABC reference frame. In this paper, besides the development and description of
the algorithms, a series of discussions, analysis and studies are performed on
the proposed control technique, including the L-C filter design issue, frequency
domain closed-current loop and closed-voltage-loop responses, and time domain
simulations and experiments under various load conditions. All the analysis,
simulations and experiments demonstrate the effectiveness of the proposed
control solution.