Three-level inverter based active power filter for the three-phase, four-wire system

In this paper, the three-phase four-wire active power filter based on a three-level neutral-point-clamped inverter is presented. The proposed active power filter and controller eliminate harmonics in all three phases as well as the neutral current. The existing neutral-point-clamped inverter for a three-phase three-wire system is used for the three-phase four-wire system since the split DC capacitors provide a neutral connection. To regulate and balance the split DC-capacitor voltages, the new control using the sign cubical hysteresis controller is proposed. The control method discerns the harmonic currents by Fast Fourier Transform choosing switching states from a switching table based on the hysteresis control. The simulation and experimental results verify the feasibility of the three-phase four- wire active power filter.

[1]  S. Srianthumrong,et al.  An active power filter with harmonic detection method based on recursive DFT , 1998, 8th International Conference on Harmonics and Quality of Power. Proceedings (Cat. No.98EX227).

[2]  A. Dastfan,et al.  Control of a new active power filter using 3-D vector control , 2000 .

[3]  Man-Chung Wong,et al.  Application of a three-level NPC inverter as a three-phase four-wire power quality compensator by generalized 3DSVM , 2006 .

[4]  Hirofumi Akagi,et al.  Active Harmonic Filters , 2005, Proceedings of the IEEE.

[5]  D. Boroyevich,et al.  Effects of imbalances and nonlinear loads on the voltage balance of a neutral-point-clamped inverter , 2005, IEEE Transactions on Power Electronics.

[6]  S. Bernet,et al.  A comparison of three-level converters versus two-level converters for low-voltage drives, traction, and utility applications , 2005, IEEE Transactions on Industry Applications.

[7]  Pekik Argo Dahono,et al.  A practical approach to minimize the zero-sequence current harmonics in power distribution systems , 1997, Proceedings of Power Conversion Conference - PCC '97.

[8]  Hirofumi Akagi,et al.  A New Neutral-Point-Clamped PWM Inverter , 1981, IEEE Transactions on Industry Applications.

[9]  J. Allmeling,et al.  A control structure for fast harmonics compensation in active filters , 2004, IEEE Transactions on Power Electronics.

[10]  Abdelaziz Chaghi,et al.  FOUR{{LEGGED ACTIVE POWER FILTER COMPENSATION FOR A UTILITY DISTRIBUTION SYSTEM , 2004 .

[11]  Subhashish Bhattacharya,et al.  Flux-based active filter controller , 1995 .

[12]  M. Depenbrock,et al.  A theoretical investigation of original and modified instantaneous power theory applied to four-wire systems , 2003 .

[13]  F. Blaabjerg,et al.  Evaluation of harmonic detection methods for active power filter applications , 2005, Twentieth Annual IEEE Applied Power Electronics Conference and Exposition, 2005. APEC 2005..

[14]  T. M. Gruzs.  A survey of neutral currents in three-phase computer power systems , 1989 .

[15]  Ned Mohan,et al.  Active filtering of harmonic currents in three-phase, four-wire systems with three-phase and single-phase nonlinear loads , 1992, [Proceedings] APEC '92 Seventh Annual Applied Power Electronics Conference and Exposition.