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Article
Publication date: 1 August 2004

Renuganth Varatharajoo and Mohamad Tarmizi Ahmad

Flywheels can serve not only as attitude control devices, but also as energy storage devices, thereby eliminating the need for conventional batteries. Hence, a combined…

Abstract

Flywheels can serve not only as attitude control devices, but also as energy storage devices, thereby eliminating the need for conventional batteries. Hence, a combined energy and attitude control system (CEACS) consisting of a double counter rotating flywheel assembly is proposed for small satellites in this paper. The energy level in CEACS depends mainly on the flywheels' speeds. Therefore, a specific flywheel energy management strategy has to be implemented to take into account the limitations of the flywheels, which has not been established until today.

Details

Aircraft Engineering and Aerospace Technology, vol. 76 no. 4
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 14 October 2009

Georgina Harell and Tugrul U. Daim

In order to compliment the growing use of renewable energies in the US, additional technologies must be employed on the bulk power system. This paper aims to forecast the

Abstract

Purpose

In order to compliment the growing use of renewable energies in the US, additional technologies must be employed on the bulk power system. This paper aims to forecast the most probable energy storage technologies.

Design/methodology/approach

The methodology was deployed in two steps: evaluate the potential energy storage technologies that could complement a wind turbine or photovoltaic system; and forecast which of these technologies is best poised to become a viable solution to the energy storage problem facing these renewable technologies.

Findings

Based on the publication and patent data, compressed air energy is set to be the fastest growing complimentary technology to wind energy. Two of these types of plants are currently in existence today as mentioned previously indicating the technology is commercially available. This technology has great potential; however, implementing this technology involves finding or creating underground airtight caverns in usable locations.

Research limitations/implications

The number of variables have been limited due to the methodologies chosen for this analysis. The research can be expanded using other criteria such as cost, cost of capital, economies of scale, environmental concerns, social and political constraints.

Originality/value

This paper provides an assessment that was indicated as necessary by those who identified the need for the development of energy storage technologies for future electricity generation.

Details

Foresight, vol. 11 no. 6
Type: Research Article
ISSN: 1463-6689

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Article
Publication date: 1 November 2006

Renuganth Varatharajoo

An architecture is proposed based on the torque mode operation for the combined energy and attitude control system (CEACS). The CEACS energy storage and attitude control…

Abstract

Purpose

An architecture is proposed based on the torque mode operation for the combined energy and attitude control system (CEACS). The CEACS energy storage and attitude control performances are demonstrated.

Design/methodology/approach

All the relevant system equations are established. The torque mode‐based architecture is designed. The architecture is evaluated through numerical treatments.

Findings

The proposed CEACS architecture can simultaneously manage the energy storage and attitude control tasks.

Research limitations/implications

This research work is exclusively for small satellites in the LEO missions. However, the proposed CEACS architecture is applicable for other missions.

Practical implications

The torque mode operation will allow an ironless motor/generator design for CEACS.

Originality/value

The results demonstrate the CEACS operation in the torque mode.

Details

Aircraft Engineering and Aerospace Technology, vol. 78 no. 6
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 3 July 2017

Ping Yang, Yawei Wang, T. Chang, H. Ma, Zhuyong Li, Zhijian Jin and Zhiyong Hong

The purpose of this paper is to propose a hybrid driving system that couples a motor and flywheel energy storage (FES) for a megawatt-scale superconducting direct current…

Abstract

Purpose

The purpose of this paper is to propose a hybrid driving system that couples a motor and flywheel energy storage (FES) for a megawatt-scale superconducting direct current (DC) induction heater. Previous studies have proven that a superconducting DC induction heater has great advantages in relation to its energy efficiency and heating quality. In this heater, a motor rotates an aluminium billet in a DC magnetic field and the induced eddy current causes it to be heated. When the aluminium billet begins to rotate, a high peak load torque appears at a low rotation speed. Therefore, driving the billet economically has been a great challenge when designing the driving system, which is the focus of this paper.

Design/methodology/approach

A hybrid driving system based on FES is designed to provide extra torque when the peak load torque occurs at a low rotation speed, which allows the successful start-up of the aluminium billet and the operation of the motor at its rated capacity. The mechanical structure of this hybrid driving system is introduced. A simulation model was constructed using Matlab/Simulink and the dynamic start-up process is analysed. The influence of the flywheel’s inertia and required minimum engagement speed are investigated.

Findings

The results of this paper show that the hybrid driving system that couples FES and a motor can successfully be used to start the aluminium billet rotating. The flywheel’s inertia and engagement speed are the most important parameters. The inertia of the flywheel decreases with an increase in its engagement speed.

Practical implications

The cost of the driving system is significantly reduced, which is very important in relation to the commercial potential of this apparatus.

Originality/value

A novel start-up strategy for driving the aluminium billet of a superconducting DC induction heater at low speed is proposed based on FES.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 4 January 2011

Abdou Tankari Mahamadou, Bailo Camara Mamadou, Dakyo Brayima and Nichita Cristian

The wind speed is very fluctuant and contains a significant energy. Taking into account the turbulent component in the energy management would increase the profitability…

Abstract

Purpose

The wind speed is very fluctuant and contains a significant energy. Taking into account the turbulent component in the energy management would increase the profitability of the wind‐diesel hybrid system. Sometimes, a diesel generator is used to compensate the requested energy but the storage devices are required to prevent disturbances induced by the wind generator current on the DCbus. The purpose of this paper is to show how the battery and flywheel (or ultracapacitors (UCs)) are used to mitigate the fluctuations of the wind generator current. The proposed method is based on the filtering of the wind generator current. The high power density sources (flywheel and UCs) are used in aims to improve the batteries' lifetime, which is estimated, in this paper, by using the rainflow cycles counting method. Spectral studies are made and the simulation and experimental results are analyzed.

Design/methodology/approach

This study is organized according to the following main and sub‐topics: wind speed characteristics, hybrid system energy management, behavioral simulations results, spectral analysis and batteries' lifetime estimation and experimental setup and results.

Findings

The simulations results highlight the interest in using a second‐order filter. The experimental results show that the fluctuations induced by the wind generator current are effectively mitigated by the storage devices.

Originality/value

The spectral analysis of the current for different filters parameters is realized and the application of the rainflow cycles counting method, in this context, is presented. This paper is interesting for the experimental hybrid system design according to the method proposed to control the DCDC converters.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 30 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 April 2005

Renuganth Varatharajoo and Ralph Kahle

To compare the conventional reaction wheel and battery systems with the combined energy and attitude control system. The system mass, volume and power requirements are…

Abstract

Purpose

To compare the conventional reaction wheel and battery systems with the combined energy and attitude control system. The system mass, volume and power requirements are revealed corresponding to the small satellite missions.

Design/methodology/approach

All the relevant system parametric equations are established. The system mass, volume and power are estimated accordingly for the conventional and the combined systems. Then, both systems are compared with respect to the typical small satellite missions.

Findings

The combined system outperforms the conventional system in most small satellite missions. However, there are some small satellite missions where the conventional systems are better in terms of the mass and volume budgets.

Research limitations/implications

This research work is exclusively for small satellites in the LEO orbits.

Practical implications

A reasonable information for sizing the combined energy and attitude control system is established. The system mass, volume and power budgets can be extracted from this research work.

Originality/value

The results provide an instant answer regarding the feasibility of the combined energy and attitude control system for small satellites.

Details

Aircraft Engineering and Aerospace Technology, vol. 77 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Content available
Article
Publication date: 1 March 2006

Abstract

Details

Aircraft Engineering and Aerospace Technology, vol. 78 no. 2
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 August 2000

Scott Thielman and Brian C. Fabien

This paper presents a novel approach to the design of composite flywheels. Specifically, the paper determines the optimal orientation of fibers in a stacked ply composite…

Abstract

This paper presents a novel approach to the design of composite flywheels. Specifically, the paper determines the optimal orientation of fibers in a stacked ply composite disk arrangement. The equations of equilibrium represent the state equations for the system. Classical lamination theory is used to develop the constitutive relations for the composite disk. This allows the orientation of the fibers in the reinforcement ply to be treated as the control variable for the problem. The Tsai‐Wu criterion, which is used to predict failure of the flywheel, is taken as the performance index. Solutions to the optimal control problem yield disk designs that provide energy densities that are 13 percent greater than a benchmark design.

Details

Engineering Computations, vol. 17 no. 5
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 17 July 2020

Sonalika Mishra, Suchismita Patel, Ramesh Chandra Prusty and Sidhartha Panda

This paper aims to implement a maiden methodology for load frequency control of an AC multi micro-grid (MG) by using hybrid fractional order fuzzy PID (FOFPID) controller…

Abstract

Purpose

This paper aims to implement a maiden methodology for load frequency control of an AC multi micro-grid (MG) by using hybrid fractional order fuzzy PID (FOFPID) controller and linear quadratic Gaussian (LQG).

Design/methodology/approach

The multi MG system considered is consisting of photovoltaic, wind turbine and a synchronous generator. Different energy storage devices i.e. battery energy storage system and flywheel energy storage system are also integrated to the system. The renewable energy sources suffer from uncertainty and fluctuation from their nominal values, which results in fluctuation of system frequency. Inspired by this difficulty in MG control, this research paper proposes a hybridized FOFPID and LQG controller under random and stochastic environments. Again to confer viability of proposed controller its performances are compared with PID, fuzzy PID and fuzzy PID-LQG controllers. A comparative study among all implemented techniques i.e. proposed multi-verse optimization (MVO) algorithm, particle swarm optimization and genetic algorithm has been done to justify the supremacy of MVO algorithm. To check the robustness of the controller sensitivity analysis is done.

Findings

The merged concept of fractional calculus and state feedback theory is found to be efficient. The designed controller is found to be capable of rejecting the effect of disturbances present in the system.

Originality/value

From the study, the authors observed that the proposed hybrid FOPID and LQG controller is robust hence, there is no need to reset the controller parameters with a large change in network parameters.

Details

World Journal of Engineering, vol. 17 no. 5
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 15 August 2019

Bartosz Ziegler, Jędrzej Mosiężny and Paweł Czyżewski

The aim of this study is to identify key factors limiting efficiency of pumped heat energy storage systems and determine some general features of transient behavior of…

Abstract

Purpose

The aim of this study is to identify key factors limiting efficiency of pumped heat energy storage systems and determine some general features of transient behavior of solid state, sensible heat storages. Moreover, it aimed at establishing a feasible approach to transient conjugate heat transfer (CHT) analyses for such applications.

Design/methodology/approach

A zero-dimensional analytical model is used to determine the system efficiency sensitivity to efficiency of its components. Analysis of argon gas flow in an exemplary configuration of layered bed thermal energy storage is presented. The analysis incorporates a unsteady reynolds averaged navier stokes model with conjugate heat transfer between gas and solid storage core.

Findings

It is established that exergetic efficiency of the heat storage is one of the key factors for the system’s overall performance. Three full cycles of storage charging and discharging having 17 h physical time in total are simulated, with calculation of exergetic efficiency for each of the cycles. From standpoint of the system efficiency, it is concluded that the presented heat storage kind has limited exergetic efficiency because of severe temperature drop at the solid–fluid interface in comparison to granular kind of heat storage devices. From the methodological standpoint, it is concluded that calculating the exergetic efficiency of the heat storage by direct computational fluid dynamics (CFD) analysis requires significant amount of walltime and computational resources.

Originality/value

The paper presents unconventional approach to using standard CFD tools by exploiting numerical diffusion to numerically suppress high-frequency solution oscillations. This strategy grants that the analysis, otherwise requiring impractically long computation walltime, is completed within a practical time.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

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