中文摘要：

风力发电具有随机性、间歇性，而且风电场一般处于偏远地区，风电经分频输电接入电网为风电的远距离输送提供了一个解决方案。该文设计了12脉波交交变频器的主电路和控制电路，并以其作为风电接入装置，用常规同步发电机模拟永磁直驱同步发电机，在动模实验室模拟了变速变频风力发电，向系统成功输送20kW有功，证实了以分频输电为背景的变速变频风力发电的可实现性，并在此基础上初步讨论了交交变频器的运行方式，实现了风电场的有功开环调节。

英文摘要：

Fractional frequency transmission system（FFTS） provides a novel approach for the remote wind farm integrated into grid. This approach could overcome the great challenges caused by the randomicity and the intermittence of the wind power. The key equipment of FFTS was cycloconverter. First, an experimental FFTS was proposed. And the power circuit and the control circuit of the 12-pulse cycloconverter were designed. In this experimental system, a synchronizing generator was used to simulate the permanent magnet synchronous generator （PMSG） in wind farm. Furthermore, the operation mode of cycloconverter was discussed. Finally, the open-loop active power regulations method was also introduced. Experiment results show that this system can transmit 20 kW electric power into grid, and verify the realizability of the system which used to integrate wind power into grid via FFTS.