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Low-frequency oscillations (LFOs) pose a significant obstacle in achieving optimal power flow and utilizing transmission corridors in large interconnected power systems. In this study, linear matrix inequality (LMI) base robust H ∞ wide-area damping controller (WADC) is introduced to effectively address critical LFOs. The proposed WADC utilizes wide-area signals, which modulate the phase angle of a thyristor-controlled phase shifter device. To ensure that the concerned modes of LFOs lie in left half of the complex plane, a D-space sub-region approach is applied. However, using wide-area signals introduces time delays, which negatively impact the efficacy of the WADC; hence, a time delay compensator (TDC) is incorporated into the feedback path of the signals. The proposed approach involves four key steps: selecting feedback signals using a combined modal transformation and geometric approach, designing an appropriate TDC, building a generalized plant with mixed sensitivity weights, and solving the LMI. The dynamic efficacy is verified on IEEE 4-machine 11-bus system, and 10-machine 39-bus system. Poorly damped single and multiple critical modes are placed in the D-space region of interest with specified damping ratios viz. 10% and 15%. Furthermore, damping ratios of critical modes are maintained with TDC based proposed WADC while deteriorating with other counterparts. [ABSTRACT FROM AUTHOR]

The impact of wind turbine system (WTS) on power system stability is elaborately addressed in the literature. However, low-frequency oscillations, especially inter-area oscillations (IAOs) can be adversely affected due to their intermittent nature. This article proposes a wide-area damping controller (WADC) for WTS-integrated power system to damp IAOs effectively. The feedback signals (linear combination of the system states) are directly measurable from phasor measurement units. Therefore a reduced-order estimator is proposed instead of a full-order estimator to design the WADC. Furthermore, to select appropriate feedback signals for WADC design, combined geometric measure and modal decomposition techniques are utilized. The overall procedure to design the reduced-order WADC includes feedback signal selection, state feedback formulation using modal transformation approach, and reduced-order estimator design using loop transfer recovery procedure. Moreover, the WADC parameters are selected considering operating point uncertainties and variable time delays in feedback signals. Performance of the proposed WADC is validated on WTS-integrated 16-machine, 68-bus system. The simulation results show that the proposed WADC gives robust performance over broad operating scenarios. [ABSTRACT FROM AUTHOR]

Damping of low-frequency oscillations (LFOs) has become a critical challenge in modern power system. Since interarea LFO modes are associated with power oscillation, therefore, proper modulation of power through energy capacitor system (ECS) can be a competent way to conserve system stability. In this article, modeling of grid-connected ECS unit is explained thoroughly. Further to provide adequate damping to critical LFO modes, a linear quadratic Gaussian (LQG) based optimal $ H_{2}$ wide-area damping controller (WADC) is proposed for ECS integrated power grid. The parameters of the proposed WADC are tuned by accelerated particle swarm optimization (APSO) technique. Furthermore, to select the proper wide-area signals for controller design, geometric approach is adopted. The efficacy of proposed methodology has been tested on large power systems containing multiple interarea modes viz. 10-machine, 39-bus system and 16-machine, 68-bus system. Simulation studies demonstrated the capability of proposed WADC to adequately damp the multiple interarea modes simultaneously. Moreover, it also provides robust performance for operating point uncertainties (load variation, permanent outage of transmission lines, etc.) and variable time delays in feedback signals. [ABSTRACT FROM AUTHOR]

Forced Oscillation (FO) has emerged as a major concern in power system due to its unpredictable frequency range. When the frequency of FO lies in the vicinity of that of the inherent natural oscillation, it can lead to resonance, posing a serious risk to the system. Improper identification and dissociation of FO in a power system can imprint huge detrimental effects, including blackouts. To address this issue, a novel method based on pattern recognition using artificial neural networks (ANNs) is proposed in this paper to classify FO and electromechanical oscillation. Multivariate time series data are collected from phasor measurement units (PMUs) placed at different buses are used as input for a two-layer NN, which is optimized using the stochastic scaled conjugate gradient algorithm. The proposed algorithm is simulated on the standard IEEE 10 machine, 39 bus system for various cases. The accuracy of the proposed algorithm is evaluated using the F1 score, obtained from the confusion plot. The results demonstrate that the network achieves a training accuracy of 97.5% and a testing accuracy of 96.67% with an F1 score of 96.7%. Additionally, ROC curves shows the efficiency of the designed model to predict the FO. • Classification of forced and natural oscillations in the grid system. • Utilization of backpropagation neural network based approach. • Classification problem framed as a sequential, multivariate time series problem. • Training network using stochastic conjugate scaled gradient optimization algorithm. • Robustness of technique using different statistical evaluation performance measures. [ABSTRACT FROM AUTHOR]

In this study, a maiden application of cascade proportional–integral–derivative with filter (PIDF) and one plus fractional-order derivative (1+FOD), i.e. PIDF(1+FOD) controller is proposed for the load frequency control mechanism. The main purpose of the cascade and fractional order controller is to increase the degree of freedom and reject the disturbances faster. A novel attempt has also been made to model a static synchronous series compensator (SSSC) with AC tie-line and HVDC tie-line. Here SSSC and HVDC tie-line are used to regulate and increase the power transfer capabilities between interconnected areas. Furthermore stored energy in the HVDC tie-line is utilised to improve the system dynamics by inertia emulation control strategy. An evolutionary salp swarm algorithm-based optimisation technique is adopted to optimise control parameters. The performance of the proposed controller is tested on a two-area hydro-thermal interconnected power system in deregulated environment. First, the effectiveness AC–DC-SSSC tie line is shown over AC-SSSC and alone AC tie-line with proposed PIDF(1+FOD) controller followed by the supremacy of proposed PIDF(1+FOD) over classical controllers. Finally, sensitivity is analysed by variation in system parameters, which shows the robustness of the proposed controller. [ABSTRACT FROM AUTHOR]

In this study, a maiden application of cascade proportional–integral–derivative with filter (PIDF) and one plus fractional‐order derivative (1+FOD), i.e. PIDF(1+FOD) controller is proposed for the load frequency control mechanism. The main purpose of the cascade and fractional order controller is to increase the degree of freedom and reject the disturbances faster. A novel attempt has also been made to model a static synchronous series compensator (SSSC) with AC tie‐line and HVDC tie‐line. Here SSSC and HVDC tie‐line are used to regulate and increase the power transfer capabilities between interconnected areas. Furthermore stored energy in the HVDC tie‐line is utilised to improve the system dynamics by inertia emulation control strategy. An evolutionary salp swarm algorithm‐based optimisation technique is adopted to optimise control parameters. The performance of the proposed controller is tested on a two‐area hydro‐thermal interconnected power system in deregulated environment. First, the effectiveness AC–DC‐SSSC tie line is shown over AC‐SSSC and alone AC tie‐line with proposed PIDF(1+FOD) controller followed by the supremacy of proposed PIDF(1+FOD) over classical controllers. Finally, sensitivity is analysed by variation in system parameters, which shows the robustness of the proposed controller. [ABSTRACT FROM AUTHOR]

This article elevates the study of Automatic Generation Control (AGC) for a multisource interconnected power system under the restructured environment. Physical constraints such as Generation Rate Constraints (GRC), Governor Dead Band (GDB) and Boiler Dynamics (BD) are incorporated into the system for a more realistic approach. Distribution Generation (DG) system is also considered to incorporate the effects of renewable energy sources penetration. A novel cascaded topology of 2-Degree of Freedom Tilted-Integral-Derivative Controller with filter (2DOF-TIDN) is proposed for anticipated AGC mechanism. A maiden application of Hybrid Salp Swarm Differential Evolution Algorithm (HSSDEA) has been successfully applied to get the different optimum gains of the proposed controller. Capacitive Energy Storage (CES) system is also incorporated for the proposed system for the AGC mechanism. The supremacy of the proposed controller is examined by comparing with other well-known or benchmark controllers. The robustness of the proposed system has been analyzed for the contract violation case of deregulation. Finally, the efficacy of the proposed work has been verified by comparing with the previously published work of literature on same platform. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Multi-source multi-area interconnected power systems with physical constraints are analyzed in deregulated scenario. • Mathematical description of AC and HVDC tie links with INEC strategy is analyzed for frequency regulation. • A novel cascaded structure of 2-DOF-PI-FOPDN is proposed successfully. • A new Volleyball Premier League (VPL) algorithm is maidenly applied for the proposed AGC controller. • The output response of the VPL algorithm based 2-DOF-PI-FOPDN controller is compared with published literature on the same platform. Abstract This paper deals with the Automatic Generation Control (AGC) strategy for multi-source interconnected power system in deregulated environment. Physical constraints like Generation Rate Constraints (GRC), Governor Dead Band (GDB) and Boiler Dynamics (BD) are incorporated in the system for the realistic approach. In this paper, an accurate model of HVDC tie-link is considered for the proposed AGC mechanism. Inertia Emulation based Control (INEC) technique is adopted to utilize the stored energy of HVDC tie-link of the interconnected power system. Distributed Generation (DG) system is also considered in the proposed AGC structure. The DG system comprises of Solar Photovoltaic (SPV), Wind Turbine System (WTS), Diesel Engine Generator (DEG), Aqua Electrolyzer (AE) and Fuel Cell (FC). Finally, a novel application of Volleyball Premier League (VPL) algorithm has been introduced to obtain the optimized gains of the proposed controller. The proposed controller includes the cascade structure of 2-Degree of Freedom Proportional-Integral controller and Fractional Order Proportional-Derivative controller with filter (2-DOF-PI-FOPDN). The robustness and effectiveness of VPL algorithm based proposed controller has been tested by comparing with the published literatures on same platform. [ABSTRACT FROM AUTHOR]

This article introduces an innovative approach for online detection and localization of forced oscillation (FO) in power systems with significant integration of wind turbine generation (WTG). The synergistic combination of Multichannel Prony analysis with Periodogram and dissipating energy flow (DEF) approach is proposed in this paper to overcome the challenges inherent in detecting FO amidst the complexities introduced by WTG integration. An adaptive version of multichannel Prony analysis is proposed in this paper that dynamically estimates Prony's system order via the recursive process. It estimates the frequency and damping ratio of all oscillatory modes, which is used to identify low damping modes that are potentially attributed to FO. Leveraging this information, the proposed method enhances both FO detection and source localization capabilities. The proposed method is verified on measurements taken from IEEE benchmark 4-machine, 11-bus system and 10-machine, 39-bus system with high wind energy penetration. Comprehensive testing demonstrates the proposed approach's effectiveness across various FO scenarios, including governor valve malfunction, exciter malfunction, and cyclic loads. Furthermore, the methodology is evaluated under resonant conditions and scenarios involving the simultaneous identification of multiple disturbances. • Detection & source location in WTG integrated power system. • MDMMO for dynamic estimation of Prony model order. • OFDM using Periodogram technique. • OFSLM using dissipating energy flow method. [ABSTRACT FROM AUTHOR]