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In this paper, reluctance synchronous machines are designed and optimised to operate in the 5 MW power range for the implementation as wind generators. It is shown, when assuming no rotor deformation, that reluctance synchronous generators can be comparatively designed to operate in this power range with power factors higher than 0.8 achieved. In order to further improve the machine performance, an...
As a kind of green energy, the wave energy exhibits high energy density, abundant global reserves, extensive application and high predictability. To this application, the direct driven linear motors already become strong candidates in recent year due to the motion feature of waves, therefore a kind PM-assisted reluctance synchronous linear generator (PMRSLG) is proposed in this paper. Based on FEA,...
This paper approaches the design using two optimization techniques for a permanent magnet generator used in a micro-wind turbine, with a major importance on the overall performances of the energy conversion system. The proposed micro-wind generator has two armatures and both are rotating in opposite directions.
Smoothing output power and alleviating mechanical loads are two main control objectives for wind energy conversion system (WECS) above rated wind speed. Conventional control methods, such as PID, cannot handle and balance multi-objective control problems. This paper presented a multi-degree of freedom, multi-objective optimization control method using model predictive approach to solve these problems...
In this paper, a multi-objective optimisation procedure based on the non-sorted genetic algorithm-II (NSGA-II) for the design of a buried PM wind generators with variable-flux is presented. A comparative analysis is carried out for optimised 13 kW, 100 kW and 1 MW buried-PM variable-flux synchronous generators (VFSG) with PMs buried deep in the rotor cores and additional rotor field coils. A design...
Transmission line switching is an important operational action in power transmission systems, and has been successfully applied to reduce generation costs and eliminate congestions. Prior work mainly focus on tackling the Optimal Transmission Switching problem based on steady states. This paper studies how to generalize these results when transmission switching is performed on highly congested systems...
This paper describes the influence of the graded air gap on the performance of a salient pole synchronous generator in terms of total harmonic distortion and air gap flux density waveform. Feasibility of redesigning an existing product to include the feature is also briefly discussed. The main focus of this investigation is the THD improvement for a skewless machine and the required increase in the...
With the increase of power offtake requirements, it is proposed that the more electric engine (MEE) draws electrical power from a generator mounted directly on the gas turbine shaft-line without the use of a gearbox. It is expected that this arrangement will improve the power density and reliability of the whole system. The challenges include limited available space, high temperature, affordability,...
The grid integration of the Doubly Fed Induction Generator (DFIG) based Wind Energy Conversion System (WECS) with the maximum energy extraction out of it is the main focus of the research now a days. The controllers employed for such controls need to be coordinated and their parameters has to be optimized. It is a very cumbersome job to find the optimal values of the control parameters of a number...
During this time, the main source of electrical energy derived from fossil energy sources, which is at present the number continues to decrease and become more limited. Therefore, it is necessary to find alternative sources of energy produced by natural processes so it will not run out or quickly reversed if managed properly. In other words, alternative energy sources must be a renewable energy. Some...
An analysis of Hybrid Excitation Synchronous Generator (HESG) topologies for a direct drive wind turbine is investigated. Through an optimization process, the topologies of HESG are compared regarding the cost and the total losses. The optimizations are performed at the nominal on-load operating point of the generator. The trade-offs between each topology are analyzed according to a set of Pareto...
High-speed magnetoelectric generators are the class of high-energy generators which are characterized by the high efficiency and reliability and the minimum specific mass in comparison with known 0.28–0.4 kg/kW generators, which defines wide prospects of their use at the space and aviation industry, as well as at the decentralized power engineering. The article discusses the problem of optimization...
This article represents the reactive power compensation issue with the help of FACTS controller and transient stability analysis in a Wind-Diesel hybrid power system. DFIG is widely used due to its simplicity and high efficiency in wind energy generation system. Back to back converters are employed in DFIG based Wind Energy Conversion System (WECS) with proper active and reactive power control strategy...
As wind turbines increase their power rating, their size and mass increase as well. Therefore, the higher reliability is needed in order to minimize maintenance. Direct-drive PM (DDPM) generators are a good solution to this problem because they omit the gearbox. The large generator mass has been also a difficult problem limiting the practical use of DDPM generators, which makes them difficult to build,...
This study is used to highlight the potentials of flux switching PM machines for medium-speed wind generator drives, considering among other things, that the rotor pole number is critical to the electromagnetic torque output. The initial result obtained by finite-element simulations and theoretical analyses of the pre-optimised 12/10 FSPM topology compared to its 12/14 counterpart show that with higher...
In this paper a grid compliant variable-flux PM generator topology for wind turbine applications is proposed. An analytical comparative study of a series-double excited synchronous generator and an electrically excited synchronous generator (SG) is carried out with particular focus on the amount of MMF required to satisfy grid codes. A finite element based design optimization of the proposed generator...
This paper proposes a new design of a fuzzy predictive controller for collective pitching of large wind turbines. Collective pitch controllers operate in region three to harvest the rated power and maintain the rated speed. The wind turbine model is represented by a Takagi-Sugeno (T-S) fuzzy model. A model predictive collective pitch controller is designed based on the fuzzy model taking into consideration...
Currently, there is significant attention being paid to the development of high-speed machines including motors and generators. In particular, permanent magnet machines are gaining more traction due to their outstanding efficiency, high power density, small size, low weight, simple mechanical construction, easy maintenance and good reliability. The higher the motor speed, the smaller the electric...
As wind turbines increase their power rating, the size and mass grows as well. The higher reliability is demanded in order to minimize the maintenance. Permanent magnet direct drive (PMDD) synchronous generators are a good solution since they omit the gearbox. While the large generator mass has been also a key difficult problem limiting the practical use of PMDD generator, which makes them difficult...
The objective of this paper is to design a state feedback controller to damp out the inter-area oscillations in the power system network with limited wide area measurements. The conventional state feedback controller designed through LQR optimization requires all the state variables as input. However, the dynamics of a power system is governed by a large number of state variables. Therefore, it is,...
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