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This work presents a novel strategy, designed from the distribution system operator viewpoint, aimed at estimating the hosting capacity in electric distribution systems when controllable plug‐in electric vehicles are in place. The strategy seeks to determine the maximum wind‐based distributed generation penetration by coordinating, on a forecast basis, the dispatch of electric vehicle aggregators, the operation of voltage regulation devices, and the active and reactive distributed generation power injections. Different from previous works, the proposed approach leverages controllable features of electric vehicles taking into account technical electric vehicle characteristics, driving behaviour of electric vehicle owners, and electric vehicle energy requirements to accomplish their primary purpose. The presented strategy is formulated as a two‐stage stochastic mixed‐integer linear programming problem. The first stage maximises the distributed generation installed capacity, while the second stage minimises the energy losses during the planning horizon. Probability density functions are used to describe the uncertainties associated with renewable distributed generation, conventional demand, and electric vehicle driving patterns. Obtained results show that controlling the power dispatched to electric vehicle aggregators can increase the distributed generation hosting capacity by up to 15% (given a 40% electric vehicle penetration), when compared to an uncontrolled electric vehicle approach. [ABSTRACT FROM AUTHOR]

Adaptive full order observer based control algorithm for unified power quality conditioner is presented. The full order adaptive observer based algorithm is capable of estimating fundamental positive sequence components parameters, including frequency, amplitude, and phase form power supply systems. Due to its adaptive response, monitoring accuracy, and faster detection of fundamental positive sequence components under all different loads and grid conditions, it is used for power quality improvement. In addition to full order adaptive observer based control algorithm, a biogeography‐based optimization method is employed here for tuning the Kp and Ki gains of a proportional integral controller on unified power quality conditioner system. The proposed method minimizes the dc‐link voltage oscillations and enhances its step response by optimally tuning the proportional integral controller. This is done by reducing the objective function of the integral time absolute error for different power quality perturbations. The numerical values obtained by biogeography based optimization are selected as proportional integral gains and it also improves the controller's performance. The full order adaptive observer control integrated with biogeography based optimization algorithm is tested interface with MATLAB/Simulink on developed unified power quality conditioner under different power quality problems at different intervals. The performance results demonstrate the quick convergence rate with effective performance. [ABSTRACT FROM AUTHOR]

Smart grid comprises utility system and dispersed renewable generations. It establishes bidirectional power transmission and communication among utility system, distributed generations and consumers. Sub‐synchronous resonance (SSR) is a major concern in transmission line. Furthermore, impedance swing during SSR leads in operation of out of step blocking characteristic of distance relay. SSR brings about a significant rise in the magnitudes of voltage and current. It also raises probability of occurrence of ferroresonance. Here, the impact of SSR in utility system is analysed on operation of doubly‐fed induction generator and distance relay with out of step blocking element is given here. Smart grid urge to establish a self‐healing protection, hence, an adaptive algorithm based on sub harmonic and ferroresonance detection is proposed for distance relay. The algorithm discriminates ferroresonance from other nonlinearities by wavelet transform and neural network and utilises time domain analysis to distinguish between different types of ferroresonance. The algorithm is able to observe smart grid protection strategy. It is capable of receiving the commands according to protection strategy to take a correct decision in such conditions to enhance reliability of power electricity in smart grid. Finally, the proposed algorithm is examined in SSR condition to certify the correct operation. [ABSTRACT FROM AUTHOR]