A simple input current wave-shaping technique for three-phase diode and SCR converters

ABSTRACT Three-phase converters using diode or silicon-controlled rectifier (SCR) are widely employed to convert the commercial AC supply to DC. Such converters inject harmonics into the power supply system and thereby distort supply system voltage waveform. A simple input current wave-shape improvement technique using a shunt-connected harmonic current compensator is presented in this work, intended to reduce the total harmonic distortion (THD) of input current of three-phase diode and SCR phase-controlled rectifiers operating with inductive loads, by matching them to the specific converter as a combined package. The compensator proposed here comprises of a three-limb voltage source converter using insulated-gate bipolar transistor, working on instantaneous current and voltage measurements of the compensator only and not of the load. The technique uses a simple feedforward control for AC source current harmonic compensation of rectifiers without monitoring the AC line currents, i.e. use of online computation. The proposed system is simulated and tested on a laboratory prototype. The measured input current THD values without additional line filters are found to be below 8.3%, which is within acceptable limits, proving that the new technique is capable of compensating predetermined current harmonics of diode or SCRs.

[1]  Jinn-Chang Wu Utility-current feedforward-based control for a single-phase active power filter , 2011 .

[2]  A. E. Emanuel,et al.  On the assessment of harmonic pollution [of power systems] , 1995 .

[3]  R. Chudamani,et al.  Comparative Evaluation of Harmonic Extraction Techniques for Three-Phase Three-Wire Active Power Filter , 2007, 2007 7th International Conference on Power Electronics and Drive Systems.

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

[5]  Kamal Al-Haddad,et al.  A review of active filters for power quality improvement , 1999, IEEE Trans. Ind. Electron..

[6]  Mauricio Aredes,et al.  Three-phase four-wire shunt active filter control strategies , 1997 .

[7]  Luca Weisz,et al.  Power Electronics Converters Applications And Design , 2016 .

[8]  Qiaofu Chen,et al.  A novel shunt hybrid active power filter based on magnetic flux compensation , 2009 .

[9]  P. Mehta,et al.  Active power filters: a review , 2000 .

[10]  Wang Lei,et al.  A harmonic injection SPWM method for the high-responsive PMSM control system , 2016 .

[11]  M. Malarvizhi,et al.  An integrated technique for eliminating harmonics of multilevel inverter with unequal DC sources , 2015 .

[12]  Samet Biricik,et al.  New hybrid active power filter for harmonic current suppression and reactive power compensation , 2016 .

[13]  N. Mohan,et al.  A comparative evaluation of harmonic reduction techniques in three-phase utility interface of power electronic loads , 1993, Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting.

[14]  Malabika Basu,et al.  Improved harmonic suppression efficiency of single-phase APFs in distorted distribution systems , 2016 .

[15]  Ward Jewell,et al.  Effects of harmonics on equipment , 1993 .

[16]  Francisco C. De La Rosa Harmonics and Power Systems , 2006 .

[17]  Jesus Leyva-Ramos,et al.  Analog Circuits to Implement Repetitive Controllers With Feedforward for Harmonic Compensation , 2007, IEEE Transactions on Industrial Electronics.

[18]  R.G. Harley,et al.  Synchronous Reference Frame Based Active Filter Current Reference Generation Using Neural Networks , 2006, IECON 2006 - 32nd Annual Conference on IEEE Industrial Electronics.

[19]  Mutsuo Nakaoka,et al.  Digital control three-phase shunt active power filter with a new harmonic-current-extraction process , 2005 .