Open Access Journal

ISSN : 2395-2717 (Online)

International Journal of Engineering Research in Computer Science and Engineering (IJERCSE)

Monthly Journal for Computer Science and Engineering

Open Access Journal

International Journal of Engineering Research in Electrical and Electronic Engineering(IJEREEE)

Monthly Journal for Electrical and Electronic Engineering

ISSN : 2395-2717 (Online)

Fuzzy Controller for Circulating Current in Parallel Three Phase PWM Converters under Generalized Unbalanced Operating Conditions

Author : M. Madhavi 1 R. Madhavi 2

Date of Publication :20th September 2017

Abstract: The use of common dc-link parallel three-phase PWM converter topology owing to advanced features & applications has become more popular, This paper proposes another control scheme for parallel three phase pulse width modulation (PWM) converters under generalized lopsided working conditions. When three-phase PWM converters are connected in parallel there exist circulating current, which result in current distortion and harmonic loss in parallel module and degrade the overall performance of the parallel system. An average model of the parallel system in positive-sequence synchronous reference frame (PSRF) is derived to dissect the impact of generalized unequal working conditions in AC side. It is seen that the variance in network frequency & the unbalance factors in filter inductance won't just offer ascent to negativesequence circulating current, additionally add to creating zero-sequence circling current (ZSCC) with the coupling between the active-reactive system. The negative-sequence circling current can be restrained by suppressing the negative-sequence parts in AC output currents of parallel modules with a proportional integral resonant (PIR) controller. An enhanced feed forward system and a fuzzy controller for ZSCC control are proposed for unequal working conditions. The unsettling influences in ZSCC caused by unbalance factors in filter inductance can be rejected with feed forward methodology. The proposed plan with a PIR, Improved feed forward & fuzzy controller can successfully stifle the circulating currents between the parallel modules and therefore, the distortions in output currents can be enormously diminished..

Reference :

    1. Puneet K. Goel, Bhim Singh, S. S. Murthy and Navin Kishore, “Parallel Operation of DFIGs in Three-Phase Four-Wire Autonomous Wind Energy Conversion System”, IEEE Trans. Ind. Appl., vol. 47, no. 4, pp. 1872-1883, Jul./Aug. 2011.
    2. Mateus F. Schonardie, Roberto F. Coelho, Romulo Schweitzer,et al, “Control of the Active and Reactive Power Using dq0 Transformation in a Three-Phase Grid-Connected PV System, ” in Proc. IEEE ISIE, Hangzhou, China, 2012, pp. 264-269.
    3. Mikel Borrega, Luis Marroyo, Roberto Gonz´alez, Juli´an Balda, and Juan Luis Agorreta, “Modelling and Control of a Master–Slave PV Inverter With N-Paralleled Inverters and Three-Phase Three-Limb Inductors”, IEEE Trans. Power Electron., vol. 28,no. 6,pp. 2842-2855, Jun. 2013.
    4. Toni Itkonen, Julius Luukko, Arto Sankala, Tommi Laakkonen, “Modeling and Analysis of the Dead-Time Effects in Parallel PWM Two-Level Three-Phase Voltage-Source Inverters,” IEEE Trans. Power Electron., vol. 24, no. 11, pp. 2446-2455, Nov. 2009.
    5. Tsung-Po Chen, “Dual-Modulator Compensation Technique for Parallel Inverters Using Space-Vector Modulation,” IEEE Trans. Ind. Electron., vol. 56, no. 8, pp. 3004-3012, Aug.2009.
    6. S. Ogasawara, J. Takagaki, H. Akagi, A. Nabae. “A novel control scheme of a parallel current-controlled PWM inverter” IEEE Trans. Ind. Appl., vol. 28, no. 5, pp. 1023-1030, Sep./Oct. 1992.
    7. K. Xing, F. C. Lee, D. Boroyevich, Z. Ye and S. K. Mazumder, “Inter-leaved PWM with discontinuous spacevector modulation,” IEEE Trans. Power Electron., vol. 14, no. 5, pp. 906-917, Sep.1999.
    8. Tsung-Po Chen. “Zero-Sequence Circulating Current Reduction Method for Parallel HEPWM Inverters Between AC Bus and DC Bus,” IEEE Trans. Ind. Electron., vol. 59, no. 1, pp. 290-300, Jan.2012.
    9. Chung-Chuan Hou. “A Multicarrier PWM for Parallel Three-Phase Active Front-End Converters,” IEEE Trans. Power Electron., vol. 28, no. 6, pp. 2753-2759,Jun. 2013. 

Recent Article