Modeling of Wind Farm Participation in AGC

Wind power has become one of the most prominent renewable energy applications in the power industry. Its annual installation is continuously setting a record high. Due to the large portion of generation mix within the system, it is desirable to operate wind power under the automatic generation control (AGC). This issue also raises another concern on the modeling of wind farms under AGC. The traditional way of portraying wind farm production in simulation is to use an aggregated wind turbine model that is generally operated in maximum power point tracking (MPPT). This approach is not suitable for wind´s participation in AGC. Therefore, more studies should be done to investigate how the individual wind turbines affect the wind farm performance under the set-point operation. This paper first illustrates the controllability of wind turbines under the set-point control. Following that, a comprehensive guidance of wind generator modeling is demonstrated to yield different approaches for developing the wind farm model. Two types of wind farm models are derived and demonstrated to portray the capability of set-point tracking under the intermittent wind condition. Associated simulations are presented and compared to show the different characteristics of these two wind farm models in depicting the set-point operation under AGC.