Analytical Prediction Method of Power System Frequency Deviation under
Uncertain Disturbances
Abstract
In modern power systems, the impact of random power sources and loads on
power systems is increasing, resulting in threatened system frequency
security. However, traditional methods are often not comprehensive in
modelling randomness, and there is no analytical method to assess the
frequency response of power systems under uncertain power disturbances.
In this paper, the power disturbance in a power system is regarded as an
interval random quantity. Based on a general model of the system
frequency response (SFR-G) and the theory of stochastic processes, an
analytical prediction method of the power system frequency deviation
under uncertain power disturbance is proposed. Through further
deduction, the allowable range of power disturbance under the premise of
secure frequency deviation can also be defined, which provides a
reference for frequency security and accident prevention in power
systems. Numerical simulations demonstrate that the proposed analytical
method can delimit the response interval of system frequency deviation
well, and the backstepping calculation can also delimit the allowable
range of power disturbance to ensure the secure operation of the system.