Verification of an Autonomous Decentralized UPS System with Fast Transient Response Using a FPGA-Based Hardware Controller

  • Yokoyama, Tomoki (Dept. of Computers and Systems Eng., Tokyo Denki University) ;
  • Doi, Nobuaki (Dept. of Computers and Systems Eng., Tokyo Denki University) ;
  • Ishioka, Toshiya (Dept. of Computers and Systems Eng., Tokyo Denki University)
  • Published : 2009.05.20

Abstract

This paper proposes an autonomous decentralized control for a parallel connected uninterruptible power supply (UPS) system based on a fast power detection method using a FPGA based hardware controller for a single phase system. Each UPS unit detects only its output voltage and current without communications signal exchange and a quasi dq transformation method is applied to detect the phase and amplitude of the output voltage and the output current for the single phase system. Fast power detection can be achieved based on a quasi dq transformation, which results in a realization of very fast transient response under rapid load change. In the proposed method, the entire control system is implemented in one FPGA chip. Complicated calculations are assigned to hardware calculation logic, and the parallel processing circuit makes it possible to realize minimized calculation time. Also, an Nios II CPU core is implemented in the same FPGA chip, and the software can be applied for non-time critical calculations. Applying this control system, an autonomous decentralized UPS system with very fast transient response is realized. Feasibility and stable operation are confirmed by means of an experimental setup with three UPSs connected in parallel. Also, rapid load change is applied and excellent performance of the system is confirmed in terms of transient response and stability.

Keywords

References

  1. J. F. Chen, and C. L. Chu, "Combination voltage- con-trolled and current-controlled PWM inverters for UPS pa-rallel operation," IEEE Trans. Power Electron., Vol.10, pp. 547-558, 1995 https://doi.org/10.1109/63.406842
  2. M. C. Chandorkar, D. M. Divan, and B. Banerjee "Control of distributed ups systems," Proc. of IEEE Power Electron-ics Specialist Conference (PESC'94), pp.197-204 1994 https://doi.org/10.1109/PESC.1994.349730
  3. A. Kawamura, and Y. Nakajima, "Proposal of autono-mously decentralized control of distinct multiple UPS's for high reliability," Proc. of IEE of Japan National Conven-tion, Vol.4, pp.140, 1996
  4. A. Kawamura, and R. Watanabe, "Autonomously decen-tralized control of multiple UPS's for higher reliability," Proc. of International Conference on Power Electronics ICPE'98, pp.836-840, 1998
  5. Eduardo Kazuhide Sato Atsuo Kawamura, "Design of an Autonomous Control for Parallel-Connected Uninterrupti-ble Power Supplies," IPEC Niigata, pp.1767-1774, 2005
  6. H.Takeda, T.Yokoyama, "A Study of Autonomous Decen-tralized Control for Single Phase UPS System based on quasi dq transformation," PESC 2005, Aachen, Germany, 2005
  7. W.Fujii, T.Yokoyama, "Construction of FPGA based hardware controller for autonomous decentralized control for UPS application," EPE-PEMC 2006, Slovenia, Portoroz, 2006
  8. T.Saito, N.Doi, T.Yokoyama, "Verification of Autonom-ous Decentralized Control UPS system using FPGA based Hardware Controller," ICPE 2007, Daegue, Korea, 2007
  9. N.Doi, T.Saito, T.Yokoyama, "Verification of the load sharing characteristics in Autonomous Decentralized UPS system using FPGA based Hardware Controller," EPE-PEMC 2008, Poznan, Poland, 2008
  10. M.Saito, T.Shimizu, "A Novel Control Method on Single Phase Grid Connectable Inverter With Hilbert Transfor-mer," IEEJ Trans. D, Vol. 121, No.10, 2001 (in Japanese)
  11. A.Takeuchi, S.Kondo, "Quick Voltage Amplitude Control on Parallel Operation of Single Phase Inverters," in Proc. of IEEJ Conf., Vol. 4, No.79 (in Japanese).
  12. T.Komiyama, T.Kojima, T.Yokoyama, "Implementation of High-speed Frequency Detection for Single Phase Utility Inter-active Inverter System," EPE-PEMC 2004, Riga, Latvia, 2004
  13. Myway labs -PSIM- http://www.myway-labs.co.jp/psim/
  14. ALTERA http://www.altera.com/