Predictive out-of-step relay based on equal area criterion and PMU data

Abstract

This paper proposes a novel-predictive and setting-free out-of-step protection technique based on synchronized phasor measurements and equal area criterion. Generator instability is predicted by comparing the acceleration and deceleration areas corresponding to the fault and postfault conditions, respectively. For each generator, the acceleration area during fault condition is calculated directly using the generator output power and rotor angle in real time. As soon as the fault is cleared, the deceleration area is predicted based on estimating the postfault Thévenin equivalent of the power network. The proposed technique is verified on the New England 39-bus test network. The effect of the proposed technique on improvement of the power network stability is compared with that of the well-known impedancebased out-of-step relay. KEYWORDS equal area criterion, impedance-based OOS relay, out-of-step, phasor measurement unit, Thévenin equivalent

Recent trends in integrity protection of power system: A literature review

“…In Reference 86, a new method for the OOS prediction of the alternator is proposed, by transforming the system into its Thevenin's Equivalent (TE). For obtaining the online TE of system, the algorithm utilizes the PMU data.…”

Novel fast and secure approach for reverse power protection in synchronous generators

“…For instance, LOE can be detected, using impedance (Z) [14,15], active power [16], or a combined index of other parameters such as load angle (δ), stator voltage or current, air-gap flux and reactive power [17][18][19][20][21]. Furthermore, OOS is another significant protection which can be detected by P and δ based on equal area criteria [22][23][24][25][26]. Therefore, the successful experience of using generator parameters in detection of LOE and OOS becomes the best motivation for the authors to find out a novel parameter-based method for generators RP protection to improve the speed and security of the previous unsuitable methods.…”

Intelligent prediction of out-of-step condition on synchronous generators because of transient instability crisis

“…In Sobbouhi and Aghamohammadi, a prediction algorithm based on the locus of rotor speed‐acceleration variation constructed from data obtained by PMU measurements is proposed and applied to a large‐scale realistic power system. In Alinezhad et al, by calculating postfault Thévenin equivalent from synchronized phasor measurements and based on equal area criterion, an OOS predictive technique is presented from which by calculating the acceleration and deceleration areas corresponding to the fault and postfault conditions, an OOS condition is predicted. In Zhang and Zhang, by using voltage phase angles of buses measured by using PMU, a new concept of coordinate transformation is presented from which the OOS centre is positioned and the splitting strategy is determined.…”

“…It is seen that generally the algorithms for recognizing OOS condition can be categorized into 2 groups: detection algorithms [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] and prediction algorithms. [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] In Table 1, it is concluded that a number of conventional methods including an adaptive OOS relay, based on the classical equal area criterion using power angle (P-δ), are proposed in which the newly developed technology of synchronized phasor measurements plays an important role. 2 In Taylor et al, 3 the property of the rate of change of apparent impedance is used for proposing an OOS relaying scheme.…”

“…Many techniques can be found in literature, and Table shows a brief review of the related researches. It is seen that generally the algorithms for recognizing OOS condition can be categorized into 2 groups: detection algorithms and prediction algorithms …”