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This paper proposes a linear feedback structure of sliding mode control for a three-phase rectifier fed by a non-ideal supply voltage. The aim of the proposed technique is to achieve power flow with unity power factor even under distorted and/or unbalanced grid voltage condition. The performance of the proposed sliding mode control strategy is investigated and compared with the traditional PI control technique. Simulation, and implementation studies are conducted to prove that the proposed scheme has better performances than traditional solutions under different operating conditions. The investigation is aimed to show proposed system robustness against grid disturbances.

Since societies depend on energy and its management, extensive changes in energy-related technologies, such as the Smart Grid (SG), are likely to bring out subsequently enormous forms of social change. Imagine, there are several claims about the risks that lie ahead as conventional energy resources terminated, as populations increase, and as assumption accelerate. Therefore, the future societies will be subject to creative development and wide-ranging transformation to optimize their energy consumption. The SG can integrate an assorted set of electricity resources, containing large power plants as well as distributed renewable energy resources, electric energy storage, demand response, and electric vehicles. In line with many visions for the SG, consumers will play a more ‘active’ role in the future energy systems. Therefore, it is necessary to ensure customers’ acceptance to successfully build a SG. The eventual deployment of the SG depends on the consumers’ acceptance of SG products and services. Yet fully engaging the residential space in the SG remains a challenge. This work aims to provide energy systems researchers and decision makers with proper insight into the underlying drivers of consumer acceptance of the SG and the logical steps for their engagement to promote the SG technology and making it feasible in a timely manner.

This paper considers a social maximize welfare problem in a micro grid. Firstly, to enhance capacity ability and the output stability of generators in a micro grid, a novel social welfare optimization problem is modeled using wavelet neural network and flywheel energy storage system. Based on augmented Lagrangian function, a continuous time distributed gradient algorithm is proposed for the novel model. In the framework of nonsmooth analysis and algebraic graph theory, we prove that with the algorithm, the optimal solution can always be found asymptotically. Simulation results on 14-bus and 100-bus systems are presented to substantiate the performance and characteristics of the proposed algorithm.

This paper proposes an effective computing framework for Short-Term Load Forecasting (STLF). The proposed technique copes with the stochastic variations of the load demand using a stacked generalization approach. This approach combines three models, namely, Light Gradient Boosting Machine (LGBM), eXtreme Gradient Boosting machine (XGB), and Multi-Layer Perceptron (MLP). The inner mechanism of Stacked XGB-LGBM-MLP model consists of generating a meta-data from XGB and LGBM models to compute the final predictions using MLP network. The performance of the proposed Stacked XGB-LGBM-MLP model is validated using two datasets from different locations: Malaysia and New England. The main contributions of this paper are: 1) A novel stacking ensemble-based algorithm is proposed; 2) An effective STLF technique is introduced; 3) A critical multi-study analysis for hyperparameter optimization with five techniques is comprehensively performed; 4) A performance comparative study using two datasets and reference models is conducted. Several case studies have been carried out to prove the performance superiority of the proposed model compared to both existing benchmark techniques and hybrid models.

This paper presents an overview for the Z-Source Converter (ZSC) as an emerging power electronics topology for dc/ac converters in general propose motor drive applications. Different ZSC topologies fed from different renewable and alternative energy sources, different motor types with different number of phases and different control algorithms will be reviewed as a part of the ZSC motor drive system. In addition, various applications of the ZSC in automotive field will be highlighted. The ZSC is very promising power electronics converter topology for motor drive applications as, it provides many advantages compared with the traditional motor drive system configuration, such as: single stage conversion with buck/boost capability, improved drive system reliability, improved efficiency, and extended output voltage range.

Wind power is characterized as intermittent with stochastic fluctuations, which can result in deviation of grid frequency and voltage when the wind power ratio is high enough. These effects have a definite impact on stability and power quality of grid operation. This paper proposes an energy storage system (ESS) based power control for a grid-connected wind power system to improve power quality and stability of the power system. Vanadium redox flow battery (VRB), as an environmentally-friendly battery provided with many advantages, is employed in the ESS. A dynamic mathematical model of VRB is built by using an equivalent circuit, and its charging and discharging characteristics are analyzed. The VRB’s stable voltage is available in a wide range (around 20–80% state of charge), which is suitable for utilization of a single-stage AC/DC converter in the VRB-based ESS. With a proposed energy storage control method, VRB-based ESS is added at the exit of the grid-connected wind farm to filter fluctuations of wind power, which ensures that smooth power will be injected into the grid and which improves power quality of the power system. Simulations and experiments are carried out to verify the proposed power control method for these grid-connected wind power systems. The grid-connected wind farm with VRB-based ESS, wind speed (characterized as gust and stochastic wind), and wind turbines are modeled in simulations. Simulation results show that the grid-injected active power from the wind farm is effectively smoothed, and reactive power support can be provided for the grid by the designed VRB-based ESS. Experimental verification is achieved with a low power bench, where a RT-LAB real-time simulation platform and a direct torque controlled induction motor simulate a real wind turbine and a wind speed model is built in the RT-LAB real-time simulation platform. The experimental results verify the proposed scheme through demonstrating a stable and smooth power flow injected into the grid though the wind power fluctuated.

The power conversion from variable AC voltage into a desired AC voltage with fixed magnitude and fixed frequency is attracting more attention especially in case of grid-connected wind generation system. Indeed, the Direct Matrix Converter (DMC) can be used as a suitable solution for such AC/AC conversion to fulfill the requirement of the output voltage with desired magnitude and frequency. Nine to three phase matrix converter developed in this paper is proposed to ensure the conversion of nine-phase input voltage into three- phase voltage, the output current magnitude and frequency control and the input current power factor control. Among the existing control techniques, The Model Predictive Control (MPC) is considered to be one of the most effective control techniques. In this paper MPC is used to control the twenty-seven switches used in the topology of the nine-to-three phase matrix converters, where the main aim is to achieve principal control functions such as, the output current magnitude and frequency control and input current control to ensure a reduced shift phase, hence a nearly unity power factor in the input side of the DMC.