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The objective of this article is to design an uncomplicated wide-area damping controller (WADC) to damp out the inter-area oscillations and to tolerate different communication failures. To design a WADC, remote signals are required and these can be transferred to the control centre through phasor measurement units. In reality, each and every time, it is not possible to receive the required data without loss or disturbance. This affected data can creates unwanted WADC output signals when combining with controller feedback gain matrix. Therefore, to address this issue, a detection & correction matrix (DCM) based WADC is proposed in this work by eliminating these unwanted output signals. It can be accomplished through by modifying the feedback gain matrix as per the loss of signals. This proposed controller can be designed by means of a state feedback control technique with suitable modifications in the feedback gain matrix as per the communication path failures. The required modification of feedback gain matrix can be done in real-time by making changes in respective columns and rows of a bad data detected generator. The IEEE-68 bus test system is considered to validate the proposed controller’s effectiveness by simulating all kinds of communication failures and disturbances.

In emergency condition due to unstable inter-area oscillations, controlled islanding is considered as the final defensive strategy against system forced splitting. Applying the strategy at the proper time is vital for preserving system security. In this respect, determining the right time for applying the controlled islanding is a crucial task. Predicting the time of uncontrolled system splitting can be used as a sign for arming the controlled islanding strategy efficiently in the right time. In this paper, based on the concept of center of inertia, two oscillating areas are represented as a generalized single machine infinite bus system (GSMIB). For the GSMIB system, based on the on-line measurement data, the locus curves of the power-angle variations of the oscillating areas are evaluated from which by means of weighted least-squares technique, the equivalent power-angle curve is estimated. For predicting the proximity of the unstable inter-area oscillation to the point of out-of-step, based on the power-angle curve of the GSMIB model an equivalent unstable equilibrium point (UEP) is evaluated. The proximity of inter-area oscillation to UEP is regarded as a new instability index. The proposed approach is demonstrated on the 39-bus New England test system and Iran 1063-bus power system with promising results. [ABSTRACT FROM AUTHOR]

Several studies have reported the improvement of system stability with a doubly‐fed induction generator (DFIG) based wind turbines. Due to the remote location of DFIG, the local signals measured may not contain the complete oscillation information of the power system. This study describes an optimisation enabled wide area damping control (WADC) for DFIG to mitigate both local and inter area oscillations. Wide area measurement systems (WAMSs) which include phasor measurement units and synchrophasors are used for a centralised controller for damping inter‐area and local oscillatory modes. The proposed damping controller parameters are optimised along with the local power system stabiliser settings for maximising the impact on system modal damping. The challenging shortcoming of WAMS based controller is the variable communication latency which can adversely affect the controller if not accounted in the controller design process. The proposed WADC algorithm addresses this issue and compensates for the delayed and time stamped error signals. The variable latencies are normalised in the optimisation algorithm in the design of controller parameters. The proposed algorithm is verified with transient simulation in PSCAD/EMTDC for the most severe three‐phase faults. A set of comprehensive case studies are performed to analyse the effectiveness of the proposed algorithm for the noisy, delayed communication signals. [ABSTRACT FROM AUTHOR]

This paper investigates the improvement in the stability of a multi-machine power system using Static Synchronous Compensator (STATCOM). A systematic procedure for modelling, simulation and optimal tuning of the parameters of a STATCOM controller for stability enhancement is presented. The design of the proposed supplementary controller is formulated as an optimization problem, and adopts the particle swarm optimisation (PSO) algorithm for the optimal tuning of the controller parameters. The performance of the proposed controller is tested in a multimachine power system and results are compared with and without controller. Simulation results under different operating conditions are presented to highlight the effectiveness of the proposed controller. [ABSTRACT FROM AUTHOR]