Mitigation of harmonic and interharmonic effects using a dithering method in adjustable speed drives

This paper presents the effect of dithering on both harmonics and interharmonics in adjustable speed drives (ASDs). Using a voltage source configuration, a six-pulse rectifier and a sinusoidal pulse width modulated (SPWM) inverter are modeled in the PSCAD/EMTDC simulation platform. The pulse width modulated (PWM) signal for the inverter is modified by means of the additive dither noise. The dither randomizes the timing of rising and falling edges of PWM signals, which eventually reduces periodic harmonics of the inverter output voltage. The reduced harmonics also affect the source voltage of the rectifier and ultimately reduce interharmonics. The mitigated harmonics and interharmonics in the ASD are quantified in conventional power spectrum. Furthermore, frequency coupling is also analyzed using cross bicoherence to investigate causes of interharmonics.

[1]  R. Hoft,et al.  Inverter harmonic reduction using Walsh function harmonic elimination method , 1997 .

[2]  Zhou Li,et al.  Interharmonic Detection Based on Support Vector Machine , 2006, 2006 1ST IEEE Conference on Industrial Electronics and Applications.

[3]  A. Assi,et al.  Reduction of EMI through switching frequency dithering , 2007, 2007 50th Midwest Symposium on Circuits and Systems.

[4]  A. Testa,et al.  On the interharmonic components generated by adjustable speed drives , 2005, IEEE Transactions on Power Delivery.

[5]  T. Zhu Exact Harmonics/Interharmonics Calculation Using Adaptive Window Width , 2007, IEEE Transactions on Power Delivery.

[6]  Yingli Cao,et al.  A new method for interharmonic detection based on harmonic filtration , 2009, 2009 2nd International Conference on Power Electronics and Intelligent Transportation System (PEITS).

[7]  A. Arapostathis,et al.  ASD System Condition Monitoring Using Cross Bicoherence , 2007, 2007 IEEE Electric Ship Technologies Symposium.

[8]  J. W. Chen,et al.  A novel algorithm in solving nonlinear equations for programmed PWM inverter to eliminate harmonics , 1997, Proceedings of the IECON'97 23rd International Conference on Industrial Electronics, Control, and Instrumentation (Cat. No.97CH36066).

[9]  C.R. Fuerte-Esquivel,et al.  Centroid PWM technique for inverter harmonics elimination , 2005, IEEE Transactions on Power Delivery.

[10]  H. Wayne Beaty,et al.  Electrical Power Systems Quality , 1995 .

[11]  Yen-Shin Lai,et al.  A novel harmonic elimination pulse-width modulation technique for static converter and drives , 1998, APEC '98 Thirteenth Annual Applied Power Electronics Conference and Exposition.

[12]  Thomas G. Habetler,et al.  Angle controlled current regulated rectifiers for AC/AC converters , 1989 .

[13]  T. Habetler,et al.  Acoustic noise reduction in sinusoidal PWM drives using a randomly modulated carrier , 1989, 20th Annual IEEE Power Electronics Specialists Conference.

[14]  L. Manz Applying adjustable-speed drives to three-phase induction NEMA frame motors , 1997 .

[15]  Alberto Abbondanti,et al.  Pulsewidth Modulated Inverter Motor Drives with Improved Modulation , 1975, IEEE Transactions on Industry Applications.