Ship electrical load analysis considering power generation efficiency

<p>This paper proposed the integration of solar energy resources into the conventional unit commitment. The growing concern about the depletion of fossil fuels increased the awareness on the importance of renewable energy resources, as an alternative energy resources in unit commitment operation. However, the present renewable energy resources is intermitted due to unpredicted photovoltaic output. Therefore, Ant Lion Optimizer (ALO) is proposed to solve unit commitment problem in smart grid system with consideration of uncertainties .ALO is inspired by the hunting appliance of ant lions in natural surroundings. A 10-unit system with the constraints, such as power balance, spinning reserve, generation limit, minimum up and down time constraints are considered to prove the effectiveness of the proposed method. The performance of proposed algorithm are compared with the performance of Dynamic Programming (DP). The results show that the integration of solar energy resources in unit<em> commitment scheduling can improve the total operating cost significantly. </em></p>

The unit commitment operation in power systems is a complex, non-linear, constrained optimization problem. The commitment and de-commitment decision presents a binary problem which needs discrete/binary optimization approaches. This paper presents a binary bat search algorithm (BBSA) to solve unit commitment (UC) problem. The bat search algorithm belongs to a meta heuristic class of optimization approaches inspired by natural echolocation behavior of bats. In order to solve binary UC problem, the real valued bat search process is mapped to binary search space using sigmoidal transformation function. The BBSA is then applied to test system with 10 thermal units. The effectiveness of the BBSA is verified against system dimension using test systems upto 100 units. Extensive numerical experiments are performed to test the effectiveness of BBSA and statistical analysis of simulation results are presented. The simulation results are presented, discussed and compared to various existing classical and heuristic approaches. The same demonstrate the superior performance of BBSA approach in solving UC problem.

Unit commitment (UC) is the process of committing the most optimal combination of generators in accordance with the power system security, load and cost. This paper proposes solution of UC problem using Forward Dynamic Programming method. The results are generated on two test systems and compared with that of the new and emerging techniques. Day ahead scheduling is done for performing the unit commitment as it is practically realizable and is the most common approach for performing UC. For this, the forecasted load demand of the day ahead is considered. The forecasted data is necessary to be considered for pre-planning the UC so that the units which may not be necessary to operate, can be shut down. Accordingly, the strategies can be developed for any real time discrepancies which may arise in the system network like load increase or decrease, faults etc. All the operational and technical constraints are taken care of during simulation. A spinning reserve is also considered to cater sudden and unexpected load increase. The simulation results obtained on two test systems are analysed and presented.

Most drying plants of small capacity for vegetables and fruits are convective without recirculation of the drying agent. Such dryers have a high energy consumption and cannot be attributed to energy-saving installations. (Research purpose) The research purpose is in developing a functional and technological scheme of an energy-efficient thermoelectric dryer that provides a reduction in energy costs during the drying process while maintaining high quality indicators of the finished product and increasing the drying efficiency. (Materials and methods) The methods of system analysis and synthesis of existing knowledge in the field of research on the development of energy-saving dryers, based on the provisions of the theory of drying, heat and mass transfer and thermoelectricity were used. (Results and discussion) The article presents the structural and functional-technological schemes of a convective condensation dryer with recirculation of the drying agent based on Peltier thermoelectric elements. The technological process and the principle of operation of a convective dryer of the condensation type with the use of a thermoelectric assembly operating in the heat pump mode were described. The article proposes a general method for calculating the heat and energy parameters of the dryer based on the heat balance equation. The thermal energy withdrawn by the hot circuit of the thermoelectric assembly, and directed to heating the cooled and drained air, exceeds the energy consumed from the electrical network. The uniform transverse blowing of the drying box with an air ensures uniform drying of the product. (Conclusions) When the drying box is cross-blown and the air flow is relatively fast, the moisture evaporation process is accelerated, the drying time is reduced and the drying quality is improved. It was revealed using preliminary technical and economic calculations that the proposed design provides a reduction in energy consumption compared to traditional dryers by up to 25 percent.

The authors propose an algorithm to consider the ramp characteristics in starting up and shutting down the generating units as well as increasing and decreasing power generation. They consider the inclusion of ramping constraints in both unit commitment and economic dispatch. Since implementing ramp-rate constraints is a dynamic process, dynamic programming (DP) is a proper tool to treat this problem. To overcome the computational expense which is the main drawback of DP, this study initially employs artificial intelligence techniques to produce a unit commitment schedule which satisfies all system and unit operation constraints except unit ramp-rate limits. Then, a dynamic procedure is used to consider the ramp properties as units are started up and shut down. According to this adjustment, maximum generating capabilities of units will change the unit operation status instead of following a step function. Finally, a dynamic dispatch procedure is adopted to obtain a suitable power allocation which incorporates the unit generating capability information given by unit commitment and unit ramping constraints, as well as the economical considerations. Two examples are presented to demonstrate the efficiency of the method. >

Shaft generators, which are inserted in the shafting between the main propulsion engine and propeller, are important source of power on ships. Detailed knowledge of electromagnetic characteristics of shaft generator is necessary for design complex ship's power system. Such knowledge is obtainable only by numerical simulations. In this paper we simulate no-load and rated load electromagnetic state in low-speed ship's generator and present methodology for calculation of reactances from field solutions. Another important problem in design of shaft generator is dimensioning of cooling system because of limited space for the generator. Therefore, we present results of numerical fluid-flow analysis of ventilator as well

Sludge recycling system is an important part of wastewater treatment plants, because the lack of control model, almost all of the sludge return system with wastewater treatment plants is simply the ratio by the amount of water to set the sludge return rate. In order to ensure the water quality with a high ratio, resulting in high energy consumption, handling capacity decreased. This paper presents the application of a fuzzy logic controller to sludge recycle flow processes to predict the amount of return sludge, adjustment return sludge dynamic real-time, saving energy costs. The Simulation results have shown the robustness of the implementation and the efficiency of the proposed control strategies, which have been operated automatically in a safe, stable and optimum operating point, improving effluent quality and reducing energy costs.

Introduction. Rack stacker cranes are the main hoisting and transport machine for maintenance of multi-level rack warehouses. The efficiency and profitability of the warehouse depends on their efficiency. The traditional design of a rack stacker crane includes a trolley that moves along the rails on the floor of a warehouse, a column mounted vertically on the trolley, along which a carriage with a load gripping device and a load rises. The disadvantages of the traditional crane design are the relatively large mass of the trolley, the need to move it along with the column in a horizontal direction when moving around the warehouse, the relatively high energy consumption and the need to strengthen the floor of the warehouse. The crane rail tracks on the floor of the warehouse must be cleared of objects falling from above, which is associated with stopping the operation of the crane and reducing productivity.Materials and Methods. The design of a stacker crane is related to the shape of its working space. In order to improve the stacker crane, its design was developed on the basis of a jib with a counterweight, which does not require rail crane tracks. The crane of the proposed design is capable of storage in the hangars of a semicircular shape. For two warehouses: traditional rectangular and semicircular shapes, a comparative analysis of the sums of geometric distances was performed when the load gripping device moved from the loading point to randomly selected target cells. As a comparison criterion, the sum of the Cartesian distances of the load gripping device movements between the warehouse loading point and the target points, randomly selected according to the law of uniform distribution, was used. Three types of crane operation cycles were studied – simple single, double and mixed.Results. Comparative diagrams of criterion values are given. It has been established that for all types of cycles studied, to the greatest extent when working on a single cycle, the use of a crane of the proposed design with the same storage capacity significantly reduces the total geometric distance that the load gripping device must pass.Discussion and conclusions. Reducing the sum of the geometric distances of movement of the load handling device of the new crane allows to conclude that the time spent on the movements that determine the productivity of the work performed by the crane, as well as the energy costs associated with them, can be significantly reduced. Reducing energy costs is possible by replacing the translational movement of a massive undercarriage with the rotational movement of a balanced jib of a relatively small mass at the crane of the proposed design. Time is not wasted on regular cleaning of the crane tracks, associated with stopping the crane. The number of friction pairs in the proposed design of the crane is reduced compared with the traditional one.

Outdated technologies in drying processes can lead to iПеrrational use of energy, as a consequence, high energy consumption and increased energy consumption. Therefore, the issues of energy saving and energy efficiency are the most important tasks to be solved. Nowadays, energy saving and energy efficiency are also part of the environmental problem. Ukraine, which has a unique geographical position for Europe, is fully supplied with natural resources, - one of the countries where there is inefficient use of energy resources. One of the energy-consuming areas of vegetable processing is drying. In the modern world, the issue of energy efficiency of drying methods is one of the most relevant areas of research. Convective drying of vegetable raw materials requires a rational use of regime parameters of the process corresponding to the biochemical properties of the processed object. The primary objectives of this area of processing of vegetable raw materials are to reduce energy costs and ensure high quality characteristics of the final product. This article presents the developed heat-technology for obtaining phytoestrogenic powder from soybeans and spinach. Which includes 3 stages: preliminary preparation of raw materials for drying; drying of thermolabile vegetable raw materials; dispersion and packaging of the obtained phytoestrogenic powder. As a result of previously conducted comprehensive research, it was found that the use of heat technology reduces energy costs at the stage of preparation of raw materials through the improvement of existing hydrothermal treatment of soybeans, as well as energy savings of 21% through the use of developed step modes. Studies of the qualitative characteristics of the obtained phytoestrogenic powder confirm the high quality of the final product.

This chapter describes and formulates three important problems for the economic management of power systems, namely, the Unit Commitment (UC), the Economic Dispatch (ED), and the Network Constrained Unit Commitment (NCUC) problems. The UC problem determines the commitment of generating units with the aim of minimizing operating costs while supplying the demand and meeting technical and security constraints. Then, once the commitment of generating units is decided, the ED problem determines the actual power output of each generating unit that is needed to supply all demands at minimum cost, while complying with the technical constraints of the transmission network. Finally, if both the commitment of generating units and transmission constraints are considered simultaneously, the resulting problem is known as the NCUC problem. These three problems are mostly considered in electricity markets throughout the US.

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This paper proposes solving short-term unit commitment (UC) problems with security constraints by hybrid chaotic particle swarm optimization (CPSO). The objective of security-constrained UC (SC-UC) is to minimize the total generation cost, which is the sum of both transition cost and production cost of the scheduled combination units. The proposed CPSO method, which involves the chaotic map and the chaotic turbulence, can avoid premature convergence of PSO and escape local minima. Moreover, the proposed hybrid CPSO method has the ability of solving both the continuous and the discrete optimal programming problems. Two power systems are demonstrated for verifying the feasibility and effectiveness of the proposed method in solving SC-UC problems with constraints of a nonlinear generator and operation security assessment taken into consideration. The simulation results show that the proposed CPSO-based SC-UC method is indeed capable of obtaining efficiently high-quality UC solutions and enhancing the system security of UC operation.

Unit commitment (UC) is a problem to economically determine the commitment status and generation level for each thermal unit during each time interval of the scheduled periods. The purpose of UC is to minimize the total generation cost while satisfying system demand, reserve requirements, and other unit constraints. The combined-cycled units have been increasingly installed throughout the world because of their high efficiency and fast response. However, the combined-cycle units usually have multiple operating configurations. The multi-configuration characteristic causes that the UC problem is more complex and difficult to be solved. In this paper, the authors present a simplified combined-cycled unit model to efficiently solve the related mixed integer linear programming-based UC problem. By simulating two test systems, results show that the proposed model is effective to reduce the complexity of problem with losing little solution accuracy.

Application of the hybrid Big Bang-Big Crunch algorithm to optimal reconfiguration and distributed generation power allocation in distribution systems

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