基于MMC-HVDC的永磁直驱风机并网控制策略

Grid Connection Control Strategy of Permanent Magnet Direct Drive Fan Based on MMC-HVDC

针对风能的不可控性、间歇性的特点及风电并网后将影响电能质量和电网稳定性的问题,提出了一种基于MMCHVDC的永磁直驱风机并网控制策略。分别在三相静止坐标系与同步旋转坐标系下建立了MMC-HVDC系统的数学模型,并提出了一种由系统级、换流站级和换流器阀级组成的三层控制策略,以有效控制模块电容电压。在Matlab仿真平台搭建的有源网络和无源网络下的测试结果表明,所提出的风机并网控制策略具有良好的动态响应特性及稳定性,能满足大容量、长距离风机并网的要求。

In view of the uncontrollable and intermittent characteristics of wind energy and the problems of power quality and grid stability after the wind power is connected to the grid,a grid- connected control strategy of permanent magnet directdrive wind turbine based on MMC- HVDC is proposed. The mathematical model of MMC-HVDC system is established under three- phase stationary coordinate system and synchronous rotating coordinate system. And a three- layer control system consisting of system level,converter station stage and converter valve stage is proposed Strategy to effectively control the module capacitor voltage. The test results under the active network and the passive network built by the Matlab simulation platform show that the proposed grid- connected control strategy has good dynamic response and stability,and can meet the requirements of high capacity and long distance fans.