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| Control Strategy to Improve the Bandwidth and Reduce the Second Harmonic Current in the Two-Stage Inverter Based on Virtual Impedance |
| Zhang Li , Ren Xiaoyong , Ruan Xinbo |
| Nanjing University of Aeronautics and Astronautics Nanjing 210016 China |
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Abstract The instantaneous output power of the two-stage single-phase inverter pulsates at twice the output voltage frequency, generating second harmonic current (SHC) in the front-end DC/DC converter. To reduce the SHC, this paper proposes a virtual-impedance-based control strategy and gives a closed-loop parameter design method when adopting a resistor as the virtual impedance. To further increase the system’s bandwidth, a control strategy with band-pass filter incorporated into the inductor current feedback path is put forward and a damping resistor is added into the band-pass filter. The proposed control strategy can not only reduce the SHC significantly, but also improve the dynamic performance of the front-end DC/DC converter effectively while guarantee the converter operating in stability. Finally, a 1kV·A prototype is built and tested in the lab, and the experimental results are given to verify the effectiveness of the proposed control strategy.
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Received: 14 September 2012
Published: 05 November 2014
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[1] Khanh L N, Seo J J, Kim Y S, et al. Power management stategies for a grid-connected PV-FC hybrid system[J]. IEEE Transactions on Power Delivery, 2010, 25(3): 1874-1882.
[2] Jiang Z H. Power management of hybrid photovoltaic- fuel cell power systems[C]. Proceedings of IEEE Power Engineering Society General Meeting, 2006: 1-6.
[3] Blaabjerg F, Teodorescu R, Liserre M, et al. Overview of control and grid synchronization for distributed power generation systems[J]. IEEE Transac- tions on Power Electronics, 2006, 53(5): 1398-1409.
[4] Xue Y, Chang L, Kjær S B, et al. Topologies of single-phase inverters for small distributed power generators: an overview[J]. IEEE Transactions on Power Electronics, 2004, 19(5): 1305-1314.
[5] Liu C, Ridenour A, Lai J S. Modeling and control of a novel six-leg three-phase high-power converter for low-voltage fuel cell applications[J]. IEEE Transactions on Power Electronics, 2006, 21(5): 1292-1300.
[6] Schenck M, Lai J S, Stanton K. Fuel cell and power conditioning system interactions[C]. Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2005: 114-120.
[7] Palma L. An active power filter for low frequency ripple current reduction in fuel cell applications[C]. Proceedings of International Symposium on Power Electronics Electrical Drives Automation and Motion, 2010: 1308-1313.
[8] Itoh J, Hayashi F. Ripple current reduction of a fuel cell for a single-phase isolated converter using a DC active filter with a center tap[J]. IEEE Transactions on Power Electronics, 2010, 25(3): 550-556.
[9] Du C, Li X, Wu X, et al. Fuel cell UPS system without bulky DC electrolytic capacitors[C]. Proceedings of IEEE International Symposium on Power Electronics for Distributed Generation Systems, 2010: 696-702.
[10] Liu C, Lai J S. Low frequency current ripple reduction technique with active control in a fuel cell power system with inverter load[J]. IEEE Transactions on Power Electronics, 2007, 22(4): 1429-1436.
[11] Wei Z, Deng X, Gong C, et al. A novel technique of low frequency input current ripple reduction in two-stage DC-AC inverter[C]. Proceeding of IEEE Industrial Electronics Conference, 2012: 139-143.
[12] Dahono P, Bahar Y, Sato Y, et al. Damping of transient oscillations on the output LC filter of PWM inverters by using a virtual resistor[C]. Proceedings of IEEE International Conference on Power Electronics and Drive System, 2001: 403-407.
[13] Vlatkovic V, Sabate J A, Ridley R B, et al. Small-signal analysis of the phase-shifted PWM converter[J]. IEEE Transactions on Power Electronics, 1992, 17(1): 128-135.
[14] Thounthong P, Davat B, Rael S, et al. Fuel cell high-power applications[J]. IEEE Industrial Electronics Magazine, 2009, 3(1): 32-46. |
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2014, Vol. 29 
