CAJ | 학술논문

为提高中远距离风电传输的经济性，提出一种新型分频多机控制策略。该系统通过一台交交变频控制多台同步风力发电机运行，并实现风电变频、并网。由于系统内各机组具有相同的定子电压，而其转子磁链方向不同，所以采用基于定子电压定向的控制方法。此外，提出一种改进的多机频率寻优方法和一种基于瞬时无功原理的数字锁相技术。前者可提高分频系统风能捕捉率和运行的稳定性，后者可解决分频系统中电压锁相不准的问题。最后，利用PSCAD搭建了由4台同步风电机构成的分频多机系统，验证了上述控制方法的可行性。
위제고중원거리풍전전수적경제성，제출일충신형분빈다궤공제책략。해계통통과일태교교변빈공제다태동보풍력발전궤운행，병실현풍전변빈、병망。유우계통내각궤조구유상동적정자전압，이기전자자련방향불동，소이채용기우정자전압정향적공제방법。차외，제출일충개진적다궤빈솔심우방법화일충기우순시무공원리적수자쇄상기술。전자가제고분빈계통풍능포착솔화운행적은정성，후자가해결분빈계통중전압쇄상불준적문제。최후，이용PSCAD탑건료유4태동보풍전궤구성적분빈다궤계통，험증료상술공제방법적가행성。
A novel fractional frequency multi-turbine (FFMT) control scheme was proposed for improving the economy of wind energy transmission of medium distance. In this system, an AC-AC converter was used to control the operation of clusters of synchronous wind generators and transmit the power to the grid. The stator voltage orientation was adopted because all the generators have the same stator voltage vector while rotor filed orientations of them are various. In addition, an improved multi-turbine frequency optimization and an instantaneous reactive power based digital phase-locked loop (PLL) were adopted. The former raised the wind energy capture and improved the stability of the system, while the latter addressed the difficulty of stator voltage orientation. Finally, the proposed scheme was validated by simulations on a wind farm composed of four wind generators.