Energy Storage Technology and Cost Characterization Report

In general, reliable PV generation prediction is required to increase complete control quality and avoid potential damage. Accurate forecasting of direct solar radiation trends in PV power production could limit the influence of uncertainties on photovoltaics, enhance organizational dependability, and maximize the utilization factor of the PV systems for something such as an energy management system (EMS) of microgrids. This paper proposes an intelligent prediction of energy production level in large PV plants through AUTO-encoder-based Neural-Network (AUTO-NN) with Restricted Boltzmann feature extraction. Here, the solar energy output may be projected using prior sun illumination and meteorological data. The feature selection and prediction modules use an AUTO encoder-based Neural Network to improve the process of energy prediction (AUTO-NN). Restricted Boltzmann Machines (RBM) can be used during a set of regulations for development-based feature extraction. The proposed model’s result is evaluated using various constraints. As a result, the proposed AUTO-NN achieved 58.72% of RMSE (Root Mean Square Error), 62.72% of n-RMSE (Normalized Root Mean Square Error), 48.04% of Max-AE (Maximum Absolute Error), 48.66% of (Mean Absolute Error), and 46.76% of (Mean Absolute Percentage Error).

https://www.mdpi.com/1999-5903/15/2/46/pdf?version=1676389463

Prediction of Energy Production Level in Large PV Plants through AUTO-Encoder Based Neural-Network (AUTO-NN) with Restricted Boltzmann Feature Extraction

Energy security is one of the most crucial factor in the development of any nation. Interconnections among different power system networks are made to lower the overall price of power generation as well as enhance the reliability and the security of electric power supply. Different types of interconnection technologies are employed, such as AC interconnections, DC interconnections, synchronous interconnections, and asynchronous interconnections. It is necessary to control the power flow between the interconnected electric power networks. The power flow controllers are used to (i) enhance the operational flexibility and controllability of the electric power system networks, (ii) improve the system stability and (iii) accomplish better utilization of existing power transmission systems. These controllers can be built using power electronic devices, electromechanical devices or the hybrid of these devices. In this paper, control techniques for power system networks are discussed. It includes both centralized and decentralized control techniques for power system networks. This paper also presents a comprehensive review of HVDC interconnections, asynchronous AC interconnections, synchronous AC interconnections and different types of power flow controllers used in these interconnections. Moreover, some important and multivariable flexible AC transmission system (FACTS) devices such as UPFC and IPFC are also discussed with their merits and limitations. Finally, a new asynchronous AC link called flexible asynchronous AC link (FASAL) system is also described in detail. At last, a summary of the comparative analysis of power system link and power flow controllers is given based on recent publications. More than 400 research articles and papers on the topic of power transfer control are covered in this review and appended for a quick reference.

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A Comprehensive Review of Power Flow Controllers in Interconnected Power System Networks

This study reviews the causes of power losses in a DC/DC converter, relates those losses with efficiency profiles, and details different strategies for maximising efficiency when several converters are placed in parallel. The research is focused on electric bus applications, where several converters are usually connected in parallel in order to fulfil the power requirements of the bus models. In a bus, the low-voltage DC link (28 V) resembles a microgrid that has some generators (DC/DC converters), an energy storage system (lead-acid batteries) and certain loads. To share the converters' output power, a droop control is proposed. Furthermore, traditional droop control is improved by adding a master-slave control. The proposed master-slave droop control improves efficiency by more than 3% at low power with no additional hardware. Experimental results show how two 5 kW converters work in parallel using the proposed control.

Master–slave DC droop control for paralleling auxiliary DC/DC converters in electric bus applications

The permanent magnet synchronous motor (PMSM) is a highly efficient energy saving machine. Due to its simple structural characteristics, good heat radiation capability, and high efficiency, PMSMs are gradually replacing AC induction motors in many industrial applications. The PMSM has a nonlinear system and lies on parameters that differ over time with complex high-class dynamics. To achieve the excessive performance operation of a PMSM, it essentially needs a speed controller for providing accurate speed tracking, slight overshoot, and robust disturbance repulsion. Therefore, this article provides an overview of different robust control techniques for PMSMs and reviews the implementation of a speed controller. In view of the uncertainty factors, such as parameter perturbation and load disturbance, the H∞ robust control strategy is mainly reviewed based on the traditional control techniques, i.e., robust H∞ sliding mode controller (SMC), and H∞ robust current controller based on Hamilton–Jacobi Inequality (HJI) theory. Based on comparative analysis, this review simplifies the development trend of different control technologies used for a PMSM speed regulation system.

/pdf/critical-review-on-robust-speed-control-techniques-for-wa7dism0.pdf

Critical Review on Robust Speed Control Techniques for Permanent Magnet Synchronous Motor (PMSM) Speed Regulation

Forecasting intra-hour solar photovoltaic energy by assembling wavelet based time-frequency analysis with deep learning neural networks

This paper presents the design of a 100kW DC/DC converter that transfer energy from/to two 125V-supercapacitor stacks to/from a 560V DC line that is attached to a three-phase inverter. The converter provides galvanic isolation between the 560V DC line and the supercapacitors. In one power flow direction, it works as a step-up DC/DC converter that maintains the DC voltage at 560V by delivering energy from the supercapacitors, and in the other direction it works as a current source to charge the supercapacitors. The proposed design is a two-stage converter: a series resonant converter that raises the supercapacitor voltage by four and provides isolation, and a half-bridge converter that maintains the output voltage by adjusting the step-up process. Experimental results are presented. The efficiency of the whole converter is higher than 91% at input currents up to 500A.

100kW bidirectional DC/DC converter for a supercapacitor stack

Fault tolerance of the bidirectional trans quasi-Z-source inverter

Transient analysis of a trans quasi-Z-source inverter working in discontinuous conduction mode

This paper presents a MATLAB/Simulink simulation model for a space vector modulated matrix converter. Indirect and direct space vector modulation methods are implemented using an almost common structure, following a shared approach. Different switching strategies are simulated and analyzed for both methods. In addition, a set of rules are proposed for direct space vector modulation switching strategies in order to simplify the implementation of its corresponding simulation model. SimPowerSystems Simulink toolbox is used in order to obtain a clearer and more flexible simulation model which results very useful in an early stage of design.

Javier Vadillo

Papers

Forecasting intra-hour solar photovoltaic energy by assembling wavelet based time-frequency analysis with deep learning neural networks

100kW bidirectional DC/DC converter for a supercapacitor stack

Fault tolerance of the bidirectional trans quasi-Z-source inverter

Transient analysis of a trans quasi-Z-source inverter working in discontinuous conduction mode

Modelling and simulation of space vector modulation techniques for Matrix Converters: Analysis of different switching strategies