Forecasting and procurement of AGC capacity requirement in electricity market environment

Automatic generation control (AGC) is one of the ancillary services (AS). It plays an important role in maintaining system frequency and scheduled tie-line interchange power within specified domains. A new framework for forecasting and procuring AGC capacity so as to well balance the economic efficiency and system security in the competitive electricity market environment is presented in this paper. First, the load deviation percentage is obtained for each studied trading period based on historical data and used to make a preliminary estimation of AGC capacity requirement, and then a dynamic adjustment model is developed to refine the estimation by taking some relevant factors such as the control performance standard (CPS), units´ regulation capabilities and load forecast errors into account. A procuring mechanism of the AGC capacity is next presented by trading off between penalties for tie-line power flow deviations and costs of AGC capacity procurement. Finally, a numerical example based on the historical data of Zhejiang provincial electricity market is served for demonstrating the essential features of the proposed model and method.