High penetration of wind turbines (WTs) is causing reduction of power system rotating inertia so that the power grid is becoming more vulnerable to large active power imbalances. Inertial control can be applied on WTs to increase their output power with a predefined power reference scheme. However, these approaches have adverse secondary frequency drop or very slow rotor speed recovery that may worsen the grid frequency regulation if an uncertain change such as wind drop occurs. This paper proposes a reliable power reference scheme for participation of WTs in grid frequency arrest that follows a linear trajectory as a function of rotor speed. Simulations on large-scale integrated wind farms into IEEE 9-bus and New England 39 bus systems are conducted and the results of grid frequency regulation in presence of different changes are studied and compared with other methods. Also, active power contribution of WTs in a combined emission economic dispatch form is studied. The results and comparisons with other methods show the effectiveness of the proposed power reference scheme of WTs in grid frequency regulation. They also show the importance of considering sudden changes during inertial control when designing an inertial control system. By using the proposed scheme, it is recommended to set power increment of WTs to half of power mismatch in the grid to obtain maximum frequency regulation. (C) 2019 Elsevier Ltd. All rights reserved.