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Demand-Side Management in Microgrids with the Presence of Renewable Sources in Vietnam
Nguyen Minh Cuong,
Nguyen Thi Dieu Huyen,
Thai Quang Vinh
Issue:
Volume 8, Issue 1, June 2019
Pages:
1-10
Received:
21 June 2019
Accepted:
11 July 2019
Published:
26 July 2019
Abstract: This paper proposes a general demand-side management strategy in microgrids with the presence of renewable sources. To apply proposed above strategy by electric price in Vietnam, it must be participated of photovoltaic and wind power generations and energy storage. An algorithm applied for this program is created by comparing amount of energy generating from generations and consumed by electric load. Amount of energy that must be bought from the grid or sells to it can be calculated by dispatching energy between hours that have the lowest electric price level and hours that have the medium and highest electric price levels. A case study that energy generating from generations is not equal energy consumed by load in hours having the medium and highest electric price levels is made more detailed in this paper. Algorithms to dispatch energy at any time to achieve the purpose of not buying electricity from the grid in above hours basing on electric price levels, efficiency of energy conversion, rated capacity of units and analysis of power flows in whole system. Results providing from algorithms are energy that must be bought from the grid or sell to the grid, instantaneous capacity of energy storage. Simulation results corresponding to this case study carried out in MATLAB 2018a present the meaning and feasibility of proposed contents.
Abstract: This paper proposes a general demand-side management strategy in microgrids with the presence of renewable sources. To apply proposed above strategy by electric price in Vietnam, it must be participated of photovoltaic and wind power generations and energy storage. An algorithm applied for this program is created by comparing amount of energy gener...
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Optimizations of Manufacturing Capabilities Through Systems Reliability Analysis and Redundancy Compliance with Operations Design and Safety Considerations
Casmir Onyeneke,
Jovita Onyeaghala,
Justin Okere,
Victor Oguanobi
Issue:
Volume 8, Issue 1, June 2019
Pages:
11-18
Received:
17 June 2019
Accepted:
12 July 2019
Published:
6 August 2019
Abstract: System and machine reliability is an important consideration that must be made when attempting the optimization of manufacturing capability; it has to be factored into the system design, layout and construction. Consideration has to be given to how reliability factors which influence the required optimization of the system, and the necessary level of its redundancy to comply with manufacturing process and safety considerations. These considerations must be made when commissioning and operating the system, with specific attention to associated maintenance requirements. These considerations and effects that redundancy engineering can have upon them are reviewed in this work indicating the latest ideas on their implementation and improvement. System availability is a consideration which is of paramount importance in the design of industrial structures. As the system becomes more complicated the cost of improving reliability also increases. Redundancy is the main avenue of increasing system availability. One of the main objectives for carrying out this research is to establish a system which optimize manufacturing capabilities through systems reliability analysis and redundancy compliance with operations design and safety considerations in a steel rolling mill. Repairable failures have been considered in most power system’s reliability analysis and that a modeling concept for unavailability due to ageing must be developed. A Normal or Weibull distribution is suggested as the means to estimate the failure probability density function due to the ageing process and a combined model is proposed including calculations for repairable and ageing failures. An example using seven generating units is used to verify the correctness of the constructed model. The results indicate that ageing failures have significant impact on the unavailability of components particularly in the case of older systems.
Abstract: System and machine reliability is an important consideration that must be made when attempting the optimization of manufacturing capability; it has to be factored into the system design, layout and construction. Consideration has to be given to how reliability factors which influence the required optimization of the system, and the necessary level ...
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Construction of a Non-negative Solution of the Leontief-Ford Model
Issue:
Volume 8, Issue 1, June 2019
Pages:
19-23
Received:
26 June 2019
Accepted:
24 July 2019
Published:
8 August 2019
Abstract: The article deals with the Leontief-Ford model, which is allowed to take into account the costs that necessary for the elimination of industrial waste. We consider its non-negative solution for those cases when the errors of the initial data have little influence on the result of the solution and for those cases when the errors of the initial data significantly affect the result of the solution. In the first case, it is called correctly delivered, and in the second incorrectly delivered. We use the iteration method to find a nonnegative solution to a correctly posed model, and also we use the regularization method to find a nonnegative solution to an ill-posed model. The developed technique is brought to a practical algorithm, which is implemented in the program "LF_2", it allows you to find a solution to the model, regardless of whether the model is correctly supplied or incorrectly supplied. An example of its application is given, where we enter the initial data of a poorly conditioned balance model into the program and obtain its non-negative solution. The results of this work may be interesting for specialists in economics and mathematical methods and models, as well as economic entities. It is known from practice that in the development of balance models of economic entities there are models with a bad number of conditionality. The application of the developed software product and methods described in this paper will allow economic entities to make quality and quick management decisions on the volume of product output of each sector of the economy, taking into account the costs necessary for the elimination of industrial waste, regardless of the conditionality and dimension of their balance models.
Abstract: The article deals with the Leontief-Ford model, which is allowed to take into account the costs that necessary for the elimination of industrial waste. We consider its non-negative solution for those cases when the errors of the initial data have little influence on the result of the solution and for those cases when the errors of the initial data ...
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Composite Reliability Index of Practical Distribution Network with PVDG Integration
Thin Thin Moe,
Myint Thuzar
Issue:
Volume 8, Issue 1, June 2019
Pages:
24-31
Received:
1 July 2019
Accepted:
23 July 2019
Published:
8 August 2019
Abstract: The benefits of the photovoltaic distributed generation (pvdg) installation in the distribution network include the total system loss reduction, voltage profile improvement and the reliability enhancement of the distribution network by minimizing the interruption and duration time to customers due to the loss of utility or due to the faults in transmission lines/equipments. in this research, the optimal size of pvdg is connected at the optimal location of practical distribution network (town pyone feeder). The multi-state model is used to calculate the probabilities of the solar irradiance data and the output power of pvdg. These probabilities of solar irradiance are applied to assess the reliability of the practical distribution network with pvdg integration. The reliability within the island operation mode of the distribution system with pvdg is presented. Analytical approach is described to assess the impact of pvdg on the system reliability due to the stochastic behavior of pv output power. a composite index organizing the impact of pvdg on the overall reliability of distribution network including interruption frequency, interruption duration and expected energy not supplied is presented. The results show that the integration of pvdg placement in the practical distribution network can improve the reliability and the applying proposed methodology can enable determining pvdg configuration concerning the overall system reliability improvement.
Abstract: The benefits of the photovoltaic distributed generation (pvdg) installation in the distribution network include the total system loss reduction, voltage profile improvement and the reliability enhancement of the distribution network by minimizing the interruption and duration time to customers due to the loss of utility or due to the faults in tran...
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