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Abstract: This paper proposes an analysis and a direct power control (DPC) design of a wind turbine driven doubly-fed induction generator (DFIG) under unbalanced network voltage conditions. A DFIG model described in the positive and negative synchronous reference frames is presented. Variations of the stator output active and reactive powers are fully deduced in the presence of negative sequence supply voltage and rotor flux. An enhanced DPC scheme is proposed to eliminate stator active power oscillation during network unbalance. The proposed control scheme removes rotor current regulators and the decomposition processing of positive and negative sequence rotor currents. Simulation results using PSCAD/EMTDC are presented on a 2-MW DFIG wind power generation system to validate the feasibility of the proposed control scheme under balanced and unbalanced network conditions.

[1] Chomat, M., Bendl, J., Schreier, L., 2002. Extended Vector Control of Doubly Fed Machine Under Unbalanced Power Network Conditions. Proc. IEEE Int. Conf. on Power Electronics, Machines and Drives, p.329-334.

[2] Gagnon, R., Sybille, G., Bernard, S., Pare, D., Casoria, S., Larose, C., 2005. Modeling and Real-time Simulation of a Doubly-fed Induction Generator Driven by a Wind Turbine. Int. Conf. on Power Systems Transients, Montreal, Canada.

[3] Gokhale, K.P., Karraker, D.W., Heikkila, S.J., 2002. Controller for a Wound Rotor Slip Ring Induction Machine. U.S. Patent, No. 6 448 735 B1.

[4] Hu, J.B., He, Y.K., 2008. Reinforced control and operation of DFIG-based wind power generation system under unbalanced grid voltage conditions. IEEE Trans. on Energy Conv., in press.

[5] Hu, J.B., He, Y.K., Nian, H., 2007. Enhanced control of DFIG-used back-to-back PWM VSC under unbalanced grid voltage conditions. J. Zhejiang Univ. Sci. A, 8(8):1330-1339.

[6] Jang, J., Kim, Y., Lee, D., 2006. Active and Reactive Power Control of DFIG for Wind Energy Conversion Under Unbalanced Grid Voltage. CES/IEEE 5th Int. Power Electronics and Motion Control Conf., p.1-5.

[7] Pena, R., Clare, J.C., Asher, G.M., 1996. Doubly fed induction generator using back-to-back PWM converters and its application to variable-speed wind-energy generation. IEEE Proc.-Electr. Power Appl., 143(3):231-241.

[8] Pena, R., Crdenas, R., Escobar, E., Clare, J., Wheeler, P., 2007. Control system for unbalanced operation of stand-alone doubly fed induction generators. IEEE Trans. on Energy Conv., 22(2):544-545.

[9] Song, H.S., Nam, K., 1999. Dual current control scheme for PWM converter under unbalanced input voltage conditions. IEEE Trans. on Ind. Electron., 46(5):953-959.

[10] Xu, L., Cartwright, P., 2006. Direct active and reactive power control of DFIG for wind energy generation. IEEE Trans. on Energy Conv., 21(3):750-758.

[11] Xu, L., Wang, Y., 2007. Dynamic modeling and control of DFIG based wind turbines under unbalanced network conditions. IEEE Trans. on Power Syst., 22(1):314-323.

[12] Zhi, D., Xu, L., 2007. Direct power control of DFIG with constant switching frequency and improved transient performance. IEEE Trans. on Energy Conv., 22(1):110-118.

[13] Zhou, Y., Bauer, P., Ferreira, J.A., Pierik, J., 2007. Control of DFIG Under Unsymmetrical Voltage Dip. IEEE Power Electronics Specialists Conf., p.933-938.