分频输电系统及其应用

分频输电系统(fractional frequency transmissionsystem,FFTS)利用较低的频率(如50/3 Hz)传输电能,从而减少交流输电线路电气距离,提高系统传输能力。在水电、风电等可再生能源发电系统中,由于发电机转速较低,十分适合于利用分频进行发电和输电,在并网时转换为工频。首先介绍了分频输电的原理、并网特点等。其次,利用2个案例对水电、风电经分频输电并网的可行性进行了分析。特别是对分频风力发/输电系统的优越性进行了阐述。结果表明,水电、风电经分频输电并网是一种具有经济与技术优势的方案,在可再生能源发输电领域有着很好的应用前景。

Fractional Frequency Transmission System and Its Applications

Fractional frequency transmission system(FFTS) is to use lower frequency,e.g.50/3 Hz,to reduce the electrical length of the AC transmission line,thus to increase its transmission capacity.FFTS is particularly suitable for transmitting electricity produced by the renewable energy,such as hydro power and wind power,because the rotation speeds of their generators are very low.The paper firstly introduced the characteristics of FFTS.Then,two case studies of the feasibility of integrating hydro plant and wind farm via FFTS were carried out.Especially,the advantage of the fractional frequency wind generation and transmission system was discussed.The results show that the proposed FFTS based approach is effective with high potential for practical implementation.