Controlling Wind Energy for Utility Grid Reliability

Abstract

Wind energy is recognized worldwide as cost-effective and environmentally friendly and is among the world's fastest-growing sources of electrical energy. Despite the amazing growth in global wind power installations in recent years, science and engineering challenges still exist.  It is commonly reported that the variability of wind is a major obstacle to integrating large amounts of wind energy on the utility grid. Wind's variability creates challenges because power supply and demand must match in order to maintain a constant grid frequency. As wind energy penetration increases to higher levels in many countries, however, systems and control techniques can be used to actively control the power generated by wind turbines and wind farms to help regulate the grid frequency. In this talk, we will first provide an overview of wind energy systems by introducing the primary structural components and operating regions of wind turbines.  The operation of the utility grid will be outlined by discussing the electrical system, explaining the importance of preserving grid reliability through controlling the grid frequency (which is a measure of the balance between electrical generation and load), and describing the methods of providing ancillary services for frequency support using conventional generation utilities.  We will then present a vision for how wind turbines and wind farms can be controlled to help stabilize and balance the frequency of the utility grid, and we will highlight control methods being developed in industry, national laboratories, and academia for providing active power ancillary services with wind energy.  Results of simulation studies as well as experimental field tests will be presented to show the promise of the techniques being developed.  We shall close by discussing future research avenues to enable widespread adoption of active power control services provided by wind farms, and how advanced distributed capabilities can reduce the integration cost of wind energy and enable much higher wind energy penetrations while simultaneously maintaining and possibly increasing the reliability of the utility grid.