tailieunhanh - From Turbine to Wind Farms Technical Requirements and Spin-Off Products phần 5

Công nghệ cơ khí hay kỹ thuật cơ khí là ngành ứng dụng các nguyên lý vật lý để tạo ra các loại máy móc và thiết bị hoặc các vật dụng hữu ích. Cơ khí áp dụng các nguyên lý nhiệt động lực học, định luật bảo toàn khối lượng và năng lượng để phân tích các hệ vật lý tĩnh và động, phục vụ cho công tác thiết kế trong các lĩnh vực như ô tô, máy bay và các phương tiện giao thông khác, các hệ thống gia nhiệt và làm lạnh, đồ dùng gia đình, máy. | Frequency Control of Isolated Power System with Wind Farm by Using Flywheel Energy Storage System 69 Fig. 5. Output power controller of FESS Fig. 6. Excitation power controller of FESS Fig. 7. Reference signal controller for frequency stabilization 70 From Turbine to Wind Farms - Technical Requirements and Spin-Off Products Wind farm model The wind farm consists of an induction generator and a wind turbine. An aerodynamic characteristic of the turbine blade expressed by eqs. 2 and 3 is adopted 5 . The captured power is expressed by eq. 1 . Since the induction generator is operated at almost constant speed approx. to pu the output power changes widely with respect to wind speed variations. Generally a wind turbine is equipped with a pitch angle controller. The conventional pitch controller shown in Fig. 8 that maintains the output of the generator to be the rated power when the wind speed is over the rated speed is also considered in this study. Parameters of the wind generator IG are shown in Table II. 1 PM 1 pCp MnRVJW 1 Cp Ằ 2 - .- 2 . R 3600 1 _ 3 Ả 1609 Active Power 100 1 1 1 5s Pitch Anglep PI controller Pitch actuator Rate limiter Max 10 sec Fig. 8. Pitch angle controller of wind turbine IG FESS Stator resistance pu Stator leakage reactance pu Magnetizing reactance pu Rotor resistance pu Rotor leakage reactance pu Table II. Parameters of induction machines. Synchronous generator model A Synchronous Generator SG is considered as a main power supply unit in the network in this study which is assumed to be a diesel engine driven power plant. The characteristics of the diesel engine and its governor system in 6 are considered. The governor controls fuel supply to maintain the engine speed at the synchronous speed. Its block diagram is shown in Fig. 9 and its parameters are shown in Table III. Frequency Control of Isolated Power System with Wind Farm by Using Flywheel Energy .