Reliability models for wind farms in generation system planning

In this paper impact of wind farm in power system reliability is investigated and a new procedure for reliability evaluation of power systems with wind farm in HLI is proposed. The proposed method is capable of finding both loss of load expectation (LOLE) and loss of energy expectation (LOEE) analytically in the presence of wind power. A wind farm in the north-western region of Iran is studied in this paper. As statistical data, wind velocity for twenty two past years is gathered and used for modeling. To accommodate time-varying patterns of wind speed, reliability analysis considering seasonal and seasonal-hourly patterns of wind speed are also performed. The results show that seasonal-hourly patterns significantly affect reliability evaluation. A reliability analysis is also performed using a load profile similar to that of Iran power network. Then for more considerations, statistical data of two other regions of Iran are used. These results explain the importance of reliability evaluation considering seasonal-hourly pattern. Beside this, it should be considered that with the increased usage of wind farms in future or in the other words with the increased penetration factor of these wind farms in the network, the hours of generation shortage are not necessarily the hours of peak in demand but also this shortage of power would be happened in hours which addition to much demand, generation of wind farms is in the lowest level because of the atmospheric situations. Survey of these cases by considering the proposed method is possible and it will design the new transition in generation programming.