Fujio Tatsuta

A New Interconnecting Method for Wind Turbine/Generators in a Wind Farm and Basic Performances of the Integrated System

A new interconnecting method for a cluster of wind turbine/generators is proposed, and some examples of the basic characteristics of the integrated system are shown. This method can be achieved with a wind turbine generating system using a shaft generator system. A group of wind turbine/generators can be interconnected easily with the proposed method, and high reliability and electric output power with high quality are also expected. Moreover, since this method enables transmission of the generated power through a long-distance dc transmission line, the optimum site for wind turbines can be selected so as to acquire the maximum wind energy.

A new interconnecting method for wind turbine/generators in a wind farm and basic characteristics of the integrated system

A new interconnecting method for a cluster of wind turbine/generators is proposed, and some examples of the basic characteristics of the integrated system are shown. This method can be achieved with wind turbine generating system using a shaft generator system. A group of wind turbine-generators can be interconnected easily with the proposed method, and high reliability and electric output power with high quality are also expected. Moreover, since this method enables to send generated power through a long-distance DC transmission line, the optimum site for wind turbines can be selected so as to acquire the maximum wind energy.

Studies on a wind turbine generator system using a shaft generator system

In this paper a new de-link type wind turbine generator system using a shaft generator system, which is widely used for power sources in a ship, is proposed. The basic configuration of the proposed wind turbine generating system is first explained. And the equations expressing the system are derived. Then the steady-state characteristics of the generating system are discussed. We use an experimental system that can simulate the characteristics of a wind turbine in this study, because it is hard to operate an actual wind turbine in a laboratory. In addition, the transient responses of this system are investigated when the velocity of the wind is changed. It is shown that experimental results were very close to the simulated ones, supporting the usefulness of the theory

Tip speed ratio control of wind turbine generating system connected in series

Experimental and simulated investigations of tip speed ratio control for a wind turbine generating system consisting of series connected two wind turbine/generators and a current-source thyristor inverter are carried out. It is confirmed that tip speed ratios of the individual turbines can be controlled almost constant when wind velocities fluctuated, making an effective operation of the system possible.

Dynamic performance analysis of a wind turbine generating system with series connected wind generators and bypass diodes using a current source thyristor inverter

Dynamic performances of a wind turbine generating system consisting of series connected wind generators with parallel connected bypass diodes at rectified DC output terminals and a current source thyristor inverter are discussed. It is shown that the tip speed ratio of the individual turbine can be controlled almost constant with the proposed method, making an effective operation of the system possible.

Performance characteristics of a practical scale wind turbine generating system using a shaft generator system

In this paper, the performances of a new and practical scale wind turbine generating system are discussed. The system was constructed on the basis of a shaft generator system widely used in large ships. This system has many features such as high reliability and output power of high quality. It is shown that electric power with constant frequency and voltage with low distortion can be obtained with this novel system. Furthermore the analytical model for computer simulation is proposed. Good agreement between simulated and experimental results is obtained, confirming the validity of the model.

Dynamic control of series connected wind turbine generating system

Dynamic control for a wind turbine generating system consisting of series connected five wind generators and a current source thyristor inverter is discussed. It is shown that tip speed ratios of the individual turbine can be controlled almost constant at an optimum condition with the proposed method, making an effective operation of the system possible. Experimental investigations are also discussed for a system with two wind turbines to verify the usefulness of the proposed generating system.

A proposal of improving the reliability of a wind farm using thyristor inverter connected in series with rectified outputs of the generators

A new topology for improving the reliability of a wind farm consisting of a set of wind turbine generators and a current-source thyristor inverter with series connected rectified outputs of the generators is proposed, and the basic characteristics of the whole system are explored from computer simulation and experimental results. In the proposed method, a diode is connected in parallel with each output of the rectifier for the turbine/generators to secure a continuing operation in the events of lack of output due to insufficient wind.

Basic investigations on a wind power plant consisting of series-connected wind turbine generators

Basic characteristics of a wind power plant consisting of plural wind generators connected in series and current-source thyristor inverter are discussed. Since this type of system does not need a substation, the cost and losses can be reduced when compared with ordinary parallel-connected systems. Here, the topology of the plant is first shown, and control method for the series-connected system is discussed to realize an optimum use of wind energy. Simulation results show that high quality output power is obtained with this type of plant. Then the effects of transmission distance and system output on the transmission efficiency, leading angle of the inverter and margin angle of the inverter are revealed. It is shown that the efficiency decreases in proportion with the distance.

A wind turbine simulator for adjusting the moment of inertia of a wind power generation system using a DC motor

In the research and development of wind turbine generating systems, it is necessary to predict the responses of the system for various cases of the wind conditions. Hence, a wind turbine simulator that can simulate the dynamic performances of actual wind turbine generating systems is very useful. In this study, a wind turbine simulator with DC motor which can simulate various performances of the whole system is developed.