Disturbance Observer-Based Prescribed Performance Fault-Tolerant Control for a Multi-Area Interconnected Power System with a Hybrid Energy Storage System

Abstract

The goal of this study is to develop a disturbance observer-based prescribed performance fault-tolerant controller (PPFTC) for a multi-area interconnected power system (MIPS) with a hybrid energy storage system (HESS). The mathematical model of the MIPS with HESS is introduced first. Then the load disturbance estimation is obtained using a disturbance observer (DO) approach. By introducing two additional functions, the tracking error is bounded to achieve the desired response. The PPFTC is further developed based on the DO ensuring that the area control error (ACE) of the MIPS asymptotically converges to zero. Finally, the effectiveness of the given PPFTC and DO are inspected through the use of the Lyapunov theory and simulated results.

Decentralized Robust Disturbance-Observer Based LFC of Interconnected Systems

“…The proposed controller with the characteristics given in Appendix A (i.e. relation (36)) is compared with the robust 𝜇synthesis controller [15], the disturbance observer-based fault-Original Modified Original Modified tolerant controller [26], and the second-order disturbance observer-based linear controller [31]. The robust 𝜇-synthesis approach [15] provides a robust controller without estimating the disturbance input.…”

“…The disturbance observer-based fault-tolerant controller estimates the disturbance input, which can be mismatched with the control input. The approach of [26] uses the information of the frequency and power of the neighbor areas to regulate the frequency of each local area. However, that control law is implemented with the same assumption of the proposed approach, in which, the frequency and power of other areas are not available.…”

“…Although the approach of [15] does not need the information of the other neighbor areas, it cannot reject the disturbance completely and compensates it with the expense of the high control input commands. The disturbance observer-based approach [26] requires the information of other areas and if this information is not available or attacked, the controller performance degrades. Furthermore, the approach of [31] does not use the information of the LFC system dynamics in the controller design procedure, which results in the simultaneous estimation of the system dynamics and the external disturbance.…”

“…Since the tie-line power and the frequency of the neighbor area are assumed to be not available, the controller cannot regulate the interconnected power to keep it as small as possible. Moreover, to quantitively compare the results of this paper with [15], [26], and [31], Table II is given. In this Table, the integral of absolute error (IAE) and integral of squared error (ISE) are provided, which reveal that the frequency deviation indices based on the proposed approach outperform those of [15], [26], and [31].…”

“…Moreover, to quantitively compare the results of this paper with [15], [26], and [31], Table II is given. In this Table, the integral of absolute error (IAE) and integral of squared error (ISE) are provided, which reveal that the frequency deviation indices based on the proposed approach outperform those of [15], [26], and [31]. 𝑅𝑒𝑓.…”