scholarly journals Perturbation Observer Based Fractional-Order Control for SMES Systems Based on Jellyfish Search Algorithm

2021 ◽  
Vol 9 ◽  
Author(s):  
Ke Luo ◽  
Yingying Jiao ◽  
Jiawei Zhu

The electric energy storage system (EESS) is considered as an efficient and promising tool to alleviate the power imbalance of grid-connected microgrid with distributed generation (DG). This work develops a perturbation observer-based fractional-order control (POFOC) strategy for superconducting magnetic energy storage (SMES) system. Initially, a high-gain state and perturbation observer (HGSPO) is designed for reliable estimation of the combined impact of the nonlinearities, parameter uncertainties, unmodeled dynamics, and external disturbances of SMES. Then the storage function of an SMES system is designed, which takes favorable terms into serious consideration to sufficiently utilize the physical properties of the SMES system. Moreover, a fractional-order control framework is applied for complete compensation for the estimated perturbation and adopted as the attached input to boost its dynamical responses. Furthermore, a newly proposed jellyfish search algorithm (JSA) is utilized to realize optimization and tuning of control gains of the developed strategy, upon which high-quality global optimum can be obtained to ensure prominent controlling performance. Case studies, e.g., active power and reactive power supply and system restoration capability under power grid fault effectively validate the effectiveness and reliability of the POFOC strategy compared with traditional PID control and interconnection and damping assignment passivity-based controller (IDA-PBC). In particular, the overshoot of PID is 115.264% of the rated value, while POFOC has no overshoot.

Energy storage system plays a crucial role in providing stabilization and improving power quality in isolated microgrid, especially in renewable energy based microgrid systems. Among the renewable sources, Photovoltaic (PV) based power systems are famous and increasing day by day due to its merits and advantages. Three phase fault are common in microgrid and leads to unsteady condition in the PV output power. When there is a fault in solar PV system, the photovoltaic power output decreases and results in abnormal voltage drop in the system. Efficiency and reliability of PV system is also a major issue. To overcome the issues occur due to fault in isolated PV system, it is to have Fault Ride through (FRT) capabilities. When failure occurs in PV system, FRT capability allows the system to maintain stability. FRT also allows the PV system to survive the system during the condition of fault on the system. Moreover, energy storage systems plays major role in the PV based systems. A Super Conducting Magnetic Energy Storage system (SMES)is proposed in this paper which is for providing power stabilization in isolated microgrid under fault condition. SMES can provide the real and reactive power according to the requirements of PV based power system. The proposed SMES can be a good solution for minimizing the effect on the system due to fault condition in PV system. Using MATLAB/SIMULINK, isolated PV with SMES was simulated and analysed for its performance with and without fault condition. This proposed theory is proven by an extensive simulation results.


2012 ◽  
Vol 535-537 ◽  
pp. 2057-2060 ◽  
Author(s):  
Xue Song Zhou ◽  
Bin Lu ◽  
You Jie Ma

Superconducting magnetic energy storage system using superconducting coils to store energy in the form of electromagnetic energy, Superconducting magnetic energy storage not only can reactive power compensation but also can active thought the power of mediation. It can achieve the power of the four-quadrant operation. This article outlines the advantages of the superconducting energy storage technology and development status, superconducting energy storage and how various components used. Finally describes how the four-quadrant active and power exchange. I think 21st century technology superconducting will develop far-reaching impact semiconductors as the 20th century semiconductors. So it has a great significance.


Author(s):  
Syed Abid Ali Shah Bukhari ◽  
Wenping Cao ◽  
Xiangping Chen ◽  
Fayyaz Jandan ◽  
Debjani Goswami

This chapter concerns energy storage technologies. It firstly outlines two popular storage technologies, batteries and supercapacitors, while their working principles are revealed. The key issues of these two technologies, such as costs, key types, capacities, etc., are also discussed. Afterwards, a hybrid electrical energy storage (HEES) system consisting of both technologies are demonstrated where the electrical circuit is illustrated. The design of the system aims to demonstrate different characteristics of these two technologies via their charging and discharging process. A test rig is explained in detail while other components, including a load bank, an inverter, a data acquisition subsystem (both the hardware and the software) are also clarified. The experimental results are illustrated and analyzed thereafter. Also, this chapter presents several other promising technologies where their key features, pros and cons, and core applications are pointedly reviewed. The concerned storage technologies include photovoltaic (PV) systems, pumped hydro-energy storage (PHES), superconducting magnetic energy storage (SMES), gas, and other alternatives sources. The authors provide the readers with a brief insight of various energy storage technologies and the inspiration of developing a low-cost, accessible energy storage system for the reader's own purposes.


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Guanglin Sha ◽  
Qing Duan ◽  
Wanxing Sheng ◽  
Aiqiang Pan ◽  
Zhe Liu ◽  
...  

In this paper, the research status of topology and control strategy of energy storage grid-connected system is analyzed, and aiming at the working characteristics of the repurposed battery, a cascade power electronic transformer (CPET) with independent DC output is proposed. The working principle of current fed isolated bidirectional DC-DC converter (CF-IBDC) and cascaded H-bridge (CHB) is analyzed, and the decoupling control strategy is designed. In this paper, a hierarchical control strategy is designed for the repurposed battery energy storage (RBES) grid-connected system based on CPET, which consists of three layers: energy layer, power layer, and state of charge (SOC) layer. The energy layer responds to active and reactive power scheduling instructions, the power layer controls the grid-connected current and tracks the grid voltage, and the SOC layer equates the charged state of repurposed batteries. A 3 MVA/12 kV three-phase grid-connected simulation system was established, and a 1 kW single-phase system experiment platform was designed. The simulation and experimental results can verify the correctness of the theoretical analysis and the feasibility of the control strategy.


Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1365
Author(s):  
Mukul Chankaya ◽  
Ikhlaq Hussain ◽  
Aijaz Ahmad ◽  
Irfan Khan ◽  
S.M. Muyeen

This paper presents Nyström minimum kernel risk-sensitive loss (NysMKRSL) based control of a three-phase four-wire grid-tied dual-stage PV-hybrid energy storage system, under varying conditions such as irradiation variation, unbalanced load, and abnormal grid voltage. The Voltage Source Converter (VSC) control enables the system to perform multifunctional operations such as reactive power compensation, load balancing, power balancing, and harmonics elimination while maintaining Unity Power Factor (UPF). The proposed VSC control delivers more accurate weights with fewer oscillations, hence reducing overall losses and providing better stability to the system. The seamless control with the Hybrid Energy Storage System (HESS) facilitates the system’s grid-tied and isolated operation. The HESS includes the battery, fuel cell, and ultra-capacitor to accomplish the peak shaving, managing the disturbances of sudden and prolonged nature occurring due to load unbalancing and abnormal grid voltage. The DC link voltage is regulated by tuning the PI controller gains utilizing the Salp Swarm Optimization (SSO) algorithm to stabilize the system with minimum deviation from the reference voltage, during various simulated dynamic conditions. The optimized DC bus control generates the accurate loss component of current, which further enhances the performance of the proposed VSC control. The presented system was simulated in the MATLAB 2016a environment and performed satisfactorily as per IEEE 519 standards.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1121
Author(s):  
Rozmysław Mieński ◽  
Przemysław Urbanek ◽  
Irena Wasiak

The paper includes the analysis of the operation of low-voltage prosumer installation consisting of receivers and electricity sources and equipped with a 3-phase energy storage system. The aim of the storage application is the management of active power within the installation to decrease the total power exchanged with the supplying network and thus reduce energy costs borne by the prosumer. A solution for the effective implementation of the storage system is presented. Apart from the active power management performed according to the prosumer’s needs, the storage inverter provides the ancillary service of voltage regulation in the network according to the requirements of the network operator. A control strategy involving algorithms for voltage regulation without prejudice to the prosumer’s interest is described in the paper. Reactive power is used first as a control signal and if the required voltage effect cannot be reached, then the active power in the controlled phase is additionally changed and the Energy Storage System (ESS) loading is redistributed in phases in such a way that the total active power set by the prosumer program remains unchanged. The efficiency of the control strategy was tested by means of a simulation model in the PSCAD/EMTDC program. The results of the simulations are presented.


2021 ◽  
Vol 69 (2) ◽  
pp. 5-12
Author(s):  
Zheng Li ◽  
Yan Qin ◽  
Xin Cao ◽  
Shaodong Hou ◽  
Hexu Sun

In order to meet the load demand of power system, BP based on genetic algorithm is applied to the typical daily load forecasting in summer. The demand change of summer load is analysed. Simulation results show the accuracy of the algorithm. In terms of power supply, the reserves of fossil energy are drying up. According to the prediction of authoritative organizations, the world's coal can be mined for 216 years. As a renewable energy, wind power has no carbon emissions compared with traditional fossil energy. At present, it is generally believed that wind energy and solar energy are green power in the full sense, and they are inexhaustible clean power. The model of wind power solar hydrogen hybrid energy system is established. The control strategy of battery power compensation for delayed power of hydrogen production is adopted, and different operation modes are divided. The simulation results show that the system considering the control strategy can well meet the load demand. Battery energy storage system is difficult to respond to short-term peak power fluctuations. Super capacitor is used to suppress it. This paper studies the battery supercapacitor complementary energy storage system and its control strategy. When the line impedance of each generation unit in power grid is not equal, its output reactive power will be affected by the line impedance and distributed unevenly. A droop coefficient selection method of reactive power sharing is proposed. Energy storage device is needed to balance power and maintain DC voltage stability in the DC side of microgrid. Therefore, a new droop control strategy is proposed. By detecting the DC voltage, dynamically translating the droop characteristic curve, adjusting the output power, maintaining the DC voltage in a reasonable range, reducing the capacity of the DC side energy storage device. Photovoltaic grid connected inverter chooses the new droop control strategy.


Sign in / Sign up

Export Citation Format

Share Document