A simplified control architecture for three-phase inverters in modular UPS application with shunt active power filter embedded

In this paper, a simplified control architecture, including individual layer control and recover layer control, is proposed for a modular online uninterruptible power supply (UPS) system is presented. The parallel control algorithm of for the DC/AC modules are mainly concentrates on the active power sharing performance due to the existence of the shunt active power filter (APF). APF will deal with the reactive power brought by the nonlinear load to guarantee that all DC/AC modules are faced with a resistive type load. On the other hand, since there is no regulation on the UPS output voltage frequency or phase angle, the recovery layer control is only concerned with the amplitude of the UPS output voltage, which means that the working load of the communication network is reduced by half. Consequently, the reliability of the system is improved. Experimental results are presented in this paper in order to validate the proposed system architecture and control.

[1]  M. Liserre,et al.  Multiple harmonics control for three-phase grid converter systems with the use of PI-RES current controller in a rotating frame , 2006, IEEE Transactions on Power Electronics.

[2]  J. Miret,et al.  A wireless controller to enhance dynamic performance of parallel inverters in distributed generation systems , 2004, IEEE Transactions on Power Electronics.

[3]  Xing Zhang,et al.  Single-Phase Uninterruptible Power Supply Based on Z-Source Inverter , 2008, IEEE Transactions on Industrial Electronics.

[4]  Josep M. Guerrero,et al.  Control of Distributed Uninterruptible Power Supply Systems , 2008, IEEE Transactions on Industrial Electronics.

[5]  Juan C. Vasquez,et al.  Hierarchical Control of Droop-Controlled AC and DC Microgrids—A General Approach Toward Standardization , 2009, IEEE Transactions on Industrial Electronics.

[6]  H. Stemmler,et al.  Stationary frame generalized integrators for current control of active power filters with zero steady state error for current harmonics of concern under unbalanced and distorted operation conditions , 2000, Conference Record of the 2000 IEEE Industry Applications Conference. Thirty-Fifth IAS Annual Meeting and World Conference on Industrial Applications of Electrical Energy (Cat. No.00CH37129).

[7]  Dehong Xu,et al.  Modeling, analysis, and implementation of parallel multi-inverter systems with instantaneous average-current-sharing scheme , 2003 .

[8]  M.D. Manjrekar,et al.  A Reconfigurable Uninterruptible Power Supply System for Multiple Power Quality Applications , 2007, IEEE Transactions on Power Electronics.

[9]  MARK WESTOBY.  Three of a kind , 1985, Nature.

[10]  Ching-Lung Chu,et al.  Combination voltage-controlled and current-controlled PWM inverters for UPS parallel operation , 1995 .

[11]  Grzegorz Benysek,et al.  Power Electronics in Smart Electrical Energy Networks , 2010 .

[12]  Jung-Min Kwon,et al.  High-Performance Transformerless Online UPS , 2008, IEEE Transactions on Industrial Electronics.

[13]  S. Buso,et al.  Robust dead-beat current control for PWM rectifiers and active filters , 1998, Conference Record of 1998 IEEE Industry Applications Conference. Thirty-Third IAS Annual Meeting (Cat. No.98CH36242).

[14]  E.R. Cadaval,et al.  Comparison of Control Strategies for Shunt Active Power Filters in Three-Phase Four-Wire Systems , 2007, IEEE Transactions on Power Electronics.

[15]  Jinjun Liu,et al.  Output impedance modeling and stability criterion for parallel inverters with average load sharing scheme in AC distributed power system , 2012, 2012 Twenty-Seventh Annual IEEE Applied Power Electronics Conference and Exposition (APEC).

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

[17]  S. Karve,et al.  Three of a kind [UPS topologies, IEC standard] , 2000 .

[18]  Josep M. Guerrero,et al.  Design and Analysis of the Droop Control Method for Parallel Inverters Considering the Impact of the Complex Impedance on the Power Sharing , 2011, IEEE Transactions on Industrial Electronics.

[19]  Wenhua Liu,et al.  Next-Generation Multi-Functional Modular Intelligent UPS System for Smart Grid , 2013, IEEE Transactions on Industrial Electronics.

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

[21]  Joachim Holtz,et al.  A high-power multitransistor-inverter uninterruptable power supply system , 1988 .