A novel communication strategy for decentralized control of paralleled multi-inverter systems

A new communication strategy for decentralized control of paralleled multi-inverter systems is introduced in this paper. The proposed strategy utilizes the common mode signal's circuit in the paralleled system as a channel of communication between individual inverters. Source voltage synchronization for paralleled inverters is presented to demonstrate its effectiveness. One inverter module acts as a source and a synchronized signal is sent by means of frequency modulation in this channel to all other modules via the common mode current. Each module will then receive and transform the signal to be used as a synchronized voltage command for individual inverters. The approach enables synchronization in the paralleled multi-inverter system and the method is not affected by external factors such as load change, output voltage variation, and different types of loads. The principle of operation, performance of the proposed strategy, as well as the experimental evaluation with three single-phase paralleled inverters are discussed and presented in this paper.

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

[2]  J. Svensson,et al.  Tuning software phase-locked loop for series-connected converters , 2005, IEEE Transactions on Power Delivery.

[3]  Tsai-Fu Wu,et al.  ACSS for paralleled multi-inverter systems with DSP-based robust controls , 2003 .

[4]  Ernane Antônio Alves Coelho,et al.  Small signal stability for parallel connected inverters in stand-alone AC supply systems , 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).

[5]  Joachim Holtz,et al.  Multi-inverter UPS system with redundant load sharing control , 1989, 15th Annual Conference of IEEE Industrial Electronics Society.

[6]  Seung-Ki Sul,et al.  A novel ride-through system for adjustable speed drives using common-mode voltage , 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]  P.D. Ziogas,et al.  A phase-locked-loop synchronization scheme for parallel operation of modular power supplies , 1989, 20th Annual IEEE Power Electronics Specialists Conference.

[9]  M. Castilla,et al.  A high-performance DSP-controller for parallel operation of online UPS systems , 2004, Nineteenth Annual IEEE Applied Power Electronics Conference and Exposition, 2004. APEC '04..

[10]  Mike Barnes,et al.  Software phase-locked loop applied to dynamic voltage restorer (DVR) , 2001, 2001 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.01CH37194).

[11]  R. Adapa,et al.  Control of parallel connected inverters in stand-alone AC supply systems , 1991, Conference Record of the 1991 IEEE Industry Applications Society Annual Meeting.

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

[13]  Tsai-Fu Wu,et al.  3C strategy for inverters in parallel operation achieving an equal current distribution , 2000, IEEE Trans. Ind. Electron..

[14]  T. Kawabata,et al.  Parallel Operation of Voltage Source Inverters , 1986, 1986 Annual Meeting Industry Applications Society.