A new government-backed study looks at overcoming some of the traditional drawbacks of wind power, such as variability and uncertainty, by using “active power control.”
The report, “Active Power Controls from Wind Power: Bridging the Gaps” was released this month by the Department of Energy’s National Renewable Energy Laboratory (NREL), and the Electric Power Research Institute (EPRI). Researchers from the University of Colorado also assisted with the 150-page document.
“Wind energy has had one of the most substantial growths of any source of power generation. In many areas throughout the world, wind power is supplying up to 20% of total energy demand, and in some instances it provides more than 50% of the power in certain regions,” according to the executive summary.
At the same time, however, variable generation like wind power “is not synchronized to the “electrical frequency of the power grid and is generally unresponsive to system frequency,” the report notes.
These three characteristics—variability, uncertainty, and asynchronism—can cause challenges for maintaining a reliable and secure power system,” NREL says in the report.
Demand response, energy storage, and improved wind power forecasting techniques have often been described as potential mitigation strategies, NREL says.
“The focus of this report is a mitigation strategy that is not often discussed and is in some ways counterintuitive: the use of wind power to support power system reliability by providing active power control (APC) at fast timescales. APC is the adjustment of a resource’s active power in various response timeframes to assist in balancing the generation and load, thereby improving power system reliability,” according to the summary.
The three forms of active power control (APC) focused on in this study are synthetic inertial control, primary frequency control (PFC), and automatic generation control (AGC) regulation. The study analyzes timeframes ranging from milliseconds to minutes to the lifetime of wind turbines, spatial scope ranging from components of turbines to large wind plants to entire synchronous interconnections, and topics ranging from economics to power system engineering to control design.
The authors of the report with collaboration from a large international industry stakeholder group, sought to understand the ways in which wind power technology can assist the power system by providing control of its active power output being injected onto the grid.