Hybrid Control of a Grid-Interactive Wind Energy Conversion System

Without storage provision, a wind energy conversion system (WECS) does not have fault ride-through capability for most temporary faults on the utility feeder. This paper proposes a hybrid valve switching and control strategy for a voltage-sourced converter (VSC) used for interfacing a WECS to the utility grid. The hybrid control of the VSC ensures continuous operation of the system in the presence of temporary single line to ground faults on the utility feeder without the need for a storage provision. The fast acting hybrid control also limits reactive fault current contribution by the converter, and therefore, avoids problems associated with overcurrent protection of the feeder. The hybrid valve switching and control of the VSC consists of: 1) sinusoidal pulse width modulation (SPWM) based valve switching and current-controlled voltage-source operation of the VSC during normal system operating conditions and 2) hysteresis space vector modulation (HSVM) based switching together with controlled current-source operation of the VSC during temporary fault conditions. The hybrid control of the VSC isolates the WECS from the grid side disturbances to ensure uninterrupted operation of the unit. Simulation studies of the grid-interactive WECS in PSCAD/EMTDC confirm the validity of the proposed hybrid control scheme.

[1]  S. Hanninen,et al.  Earth faults and related disturbances in distribution networks , 2001, 2001 Power Engineering Society Summer Meeting. Conference Proceedings (Cat. No.01CH37262).

[2]  M.W. Davis,et al.  Distributed resource electric power systems offer significant advantages over central station generation and T & D power systems. II , 2002, IEEE Power Engineering Society Summer Meeting,.

[3]  R. Hill,et al.  Static power converters of 500 kW or less serving as the relay interface package for nonconventional generators , 1994 .

[4]  Bong-Hwan Kwon,et al.  A novel SVM-based hysteresis current controller , 1998 .

[5]  C. J. Hatziadoniu,et al.  Power conditioner control and protection for distributed generators and storage , 2003 .

[6]  L. Freris.  Wind energy conversion systems , 1990 .

[7]  M. B. Brennen,et al.  Vector analysis and control of advanced static VAr compensators , 1991 .

[8]  Y. Lai,et al.  A new space vector modulation technique for inverter control , 1999, 30th Annual IEEE Power Electronics Specialists Conference. Record. (Cat. No.99CH36321).

[9]  P.P. Barker,et al.  Determining the impact of distributed generation on power systems. I. Radial distribution systems , 2000, 2000 Power Engineering Society Summer Meeting (Cat. No.00CH37134).

[10]  Bimal K. Bose,et al.  Modern Power Electronics and AC Drives , 2001 .

[11]  J.G. Slootweg,et al.  Impacts of distributed generation on power system transient stability , 2002, IEEE Power Engineering Society Summer Meeting,.

[12]  E.F. El-Saadany,et al.  A novel energy operator algorithm for voltage envelope tracking , 2005, IEEE Transactions on Power Systems.