Papers by Keyword: Wind Power Generation

Abstract: There is a continuous global need for more energy, which must be cleaner than energy produced from the conventional generation technologies. As such, this need has necessitated the increasing penetration of distributed generation technologies and primarily on renewable energy sources. This paper presents a dynamic modeling and control strategy for a sustainable micro-grid, principally powered by multiple renewable energy sources (solar energy, wind energy and Fuel cell), micro sources (such as diesel generator, micro-gas turbine etc.) and energy storage scheme. More importantly, a current-source-interface, multiple-input dc-dc converter is utilized to coordinate the sustainable power sources to the main dc bus. Thus, for tracking maximum power available in solar energy, maximum power point tracking algorithm is applied. The proposed system is designed to meet load demand, manage power flow from various sources, inject excess power into the grid, and charge the battery from the grid as needed. More so, the proposed converter architecture has reduced number of power conversion stages with less component count, and reduced losses compared to existing grid-connected hybrid systems. This improves the efficiency and reliability of the system. The utilization of energy storage is essential owing to the intermittent nature of the renewable energy sources and the consequent peak power shift between the sources and the load. Following this further, a supervisory control system is designed to handle various changes in power supply and power demand by managing power intermittency, power peak shaving, and long-term energy storage. The entire hybrid system is described given along with comprehensive simulation results that reveal the feasibility of the whole scheme. The system model is designed and simulated in MATLAB SimPowerSystem in order to verify the effectiveness of the proposed scheme.

Abstract: There are many types of wind turbine. Large propeller-type wind turbines are used mainly for large wind farms and offshore wind power generation. Small vertical-axis wind turbines (VAWTs) are often used in distributed energy systems. In previous studies on wind turbines, the basic characteristics such as torque coefficient have often been obtained during rotation, with the turbine rotating at a constant speed. Such studies are necessary for the proper design of wind turbines. However, it is also necessary to conduct research under conditions in which the wind direction and wind speed change over time. Numerical simulation of the starting characteristics is carried out in this study. Based on the flow field around the wind turbine, the force required to rotate the turbine is calculated. The force used to stop the turbine is modeled based on friction in relation to the bearing. Equations for the motion of the turbine are solved by their use as external force. Wind turbine operation from the stationary state to the start of rotation is simulated. Five parameters, namely, blade length, wind turbine radius, overlap, gap, and blade thickness, are changed and the optimum shape is obtained. The simulation results tend to qualitatively agree with the experimental results for steadily rotating wind turbines in terms of two aspects: (1) the optimal shape has an 20% overlap of the turbine radius, and (2) the larger the gap, the lower the efficiency.

Abstract: This paper deals with experimental verification and performance analysis of permanent magnet synchronous generator (PMSG) for wind power generation considering magnetic losses using d-q axis model. The d-q voltage equation of the PMSG is derived. The equations for losses such as copper loss, core loss and mechanical loss are also derived. Finally, by implementing dynamic simulation block diagram for the prediction of generating performance considering losses using MATLAB/SIMULINK, the generating performances of the PMSG are predicted under various speeds and loads. The predicted results are validated extensively by finite element (FE) analyses and measurements.

Abstract: This paper uses Z source inverter in switched reluctance wind power generation (SRWPG) to connect to power grid. According to operation of switched reluctance generator (SRG), requirements of grid-connection and the unique single stage buck boost feature of Z source inverter, Z source inverter with space vector pulse with modulation (SVPWM) is adopted to satisfy the voltage level of grid-connection. A control method of grid-connection inverter is developed to keep the capacitor voltage of Z source inverter stable and regulate the active and reactive power. Simulation of SRG and Z source inverter are constructed based on MATLAB/Simulink platform. Simulation results reveal that Z source inverter is feasible and valuable in wind power generation on SRG system.

Abstract: The amount of random variation of wind speed, wind turbine output power are volatile, a lot of wind power will be on the safe and stable operation of power systems and power quality pose serious challenges, so the wind farm wind speed and power generation forecast scheduling and management of wind farms play an important role. According wind with chaotic discuss the use of phase space CC method to reconstruct the chaotic time series, and the phase space of a wind farm 10 units were reconstructed using the weighted first order local prediction model to obtain short-term within 1h wind forecast values obtained using the power curve conversion method of generating power for each unit. By examples show that the proposed method is feasible and effective.

Abstract: The type selection and design of the wind turbine foundation play a vital role in reducing the structure cost and guaranteeing the safety of the wind turbine operation. Using a new type of beam slab foundation as the research object, this study designs the prestressed anchor beam slab foundation, and optimizes the size of the former designing scheme by using Ansys finite element software, hope to be helpful for the relevant research and design reference.

Abstract: In order to make better use of wind resources and reduce abandoned wind and improve capacity of grid accepting wind power ,this paper studies the feasibility of storing abandoned wind based on using the PHS(Pumped Hydro System). The paper has constructed model of Wind – PHS co-generation system based on operating characteristics of various types of power. Under the constraints of system demands and the technical characteristics of various types of power, the model use the minimum total operation cost of the system as the objective function, then use real coding genetic algorithm simulation to solve the problem. The results show that the use of pumped storage power station can not only reduce the abandoned wind, and the economic benefits of storage abandoned wind are better than the economic benefits of without wind abandoned. At last with evaluation and factors influencing the analysis, the conclusion that the optimal capacity of pumped storage power station in the system is expected to providing a reference which can help for the rational allocation of resources.

Abstract: A control strategy for the wind power smoothing is proposed based on the analysis of the wind power energy capture. In the proposed method, the power reference command of double-fed induction generator is adjusted by using a factor, which can be determined by the system operator according to the system spinning reserve requirements. The power reference command is used to control the wind power generator speed and the pitch angle of the wind turbine. The newly proposed strategy has some advantages compared with the proposed methods in literatures. Simulation test for a wind farm with 6×1.5MW DFIG verifies the proposed wind power fluctuation smoothing strategy.

Abstract: The exiting of wind turbines will cause the adverse effect on the power grid and its assembling unit in network voltage drops. So, direct-drive wind power generation system should meet the requirement of the certain ability of low voltage. This paper introduces the influence of wind power system with different structure by voltage drop as well as the disadvantage and advantage on LVRT. The relate regulations based on LVRT are analyzed. The existing LVRT technologies of direct-drive wind power systems are briefly presented. The characteristics of each scheme from the different LVRT technology are analyzed. Moreover, further study of LVRT for PMSG is pointed out.

Abstract: Currently, the problem of energy crisis and environmental deterioration on the world is extremely urgent, so people now are trying to turn to many kinds of renewable energy to solve these problems. Of these renewable energies, because of its cleanness and availability, wind power has broadened prospect and in recent years, it is considered to connect wind power to the grid in large quantities to make full use of it. However, wind power possesses the shortcoming such as randomness so that when it is connected to the grid, it may have great impact to the grid and damage the balance of the power system. Based on the fluctuation regularity of load and the characteristics of volatility, intermittent and randomness of wind power, the operation characteristics when large-scale wind power is connected to the grid and active regulation characteristics of conventional power source such as fire power, the multi time-scale “source to source” active coordinated control technique is proposed.