Stochastic Small Signal Interval Stability of Power Systems with Asynchronous Wind Turbine Generators

Zhen Zhang,Yanhong Liu

doi:10.1155/2018/7617394

Abstract

The stochastic dynamic interval model of power systems with asynchronous wind turbine generators is established with consideration of the interval uncertain parameters and random small excitation disturbances. The conditions of interval mean stability and interval mean square stability of the power systems are proposed. The relationship between the bounds of the mean (mean square) error and the parameter interval range of the systems is discussed. Finally, we simulate the power systems to demonstrate the effectiveness of the proposed results.

Highlights

With the rapid development of wind power and other emerging new energy and grid, the random excitation has a significant impact on the power systems stability and power quality [1,2,3]
Noticing that the mean and mean square stability [14, 15] are of great importance for power systems, the small signal mean stability and mean square stability of power systems under random excitation were investigated by some researchers
In [2], Zhang et al put forward a stochastic differential equation model for power system under Gauss type random excitation and proposed some conditions for the mean stability and mean square stability of the system

Summary

Introduction

With the rapid development of wind power and other emerging new energy and grid, the random excitation has a significant impact on the power systems stability and power quality [1,2,3]. There have been no researches carried out for the stochastic mean stability and mean square stability analysis of power systems with both consideration of random excitation disturbances and interval parameter uncertainties. Substituting (9) into (10), we have the stochastic dynamic model of the asynchronous wind turbine generators as follows: Tw − Kθw. The stochastic dynamic interval model of power systems with asynchronous wind turbine generators is established with consideration of the parameter uncertainty of D. The stochastic dynamic interval model of the power systems with asynchronous wind turbine generators can be formulated as dx (t) = (A∗ + ΔA) x (t) dt + Gdt + A󸀠dB (t) .

Stochastic Small Signal Interval Stability Analysis of the Power Systems

Simulation

Conclusions