We studied the role and mechanisms of influence of the derivatives of capacities of wind power plants and regulating generators on frequency stabilization in integrated power systems. In the course of analysis of the obtained results, we introduced a new qualitative indicator R, which corresponds to the ratio of maximal modulus of the derivative of regulator capacity to maximal modulus of the derivative of capacity of wind power plant. The use of this indicator made it possible to determine the required operation speed of regulators to ensure the reliable control of frequency and capacity in a power system with wind power plants. In particular, we established that, with increase in the value of R, the quality of frequency and capacity regulation in power system becomes better. According to the data obtained, the necessary frequency accuracy according to requirements of the Ukrainian Integrated Power System and ENTSO-E is already satisfied at values of the parameter R equal to 0.57 and 0.86, respectively. However, the deviation of power generated by the tandem of regulator – wind power plant from the assignment of central control room reaches 10.3 and 1.9%, which can lead to exceeding the voltage settings at assemblies of the connection of wind plant to the power system. Therefore, configuring the frequency and power stabilization system, we should take into account the satisfaction of requirements for both frequency and power deviation. As shown in our above studies, these requirements are simultaneously satisfied at a value of the parameter R equal to one. It was also found that further increasing the operation speed of regulator over the value, determined by the optimal level of parameter R, does not provide additional technological advantages, but can worsen the economic characteristics of regulator.