新型水平轴定桨距永磁直驱潮流能发电系统设计及应用

双向潮流适应性和运行可靠性是水平轴潮流能发电系统需要解决的两个关键问题。文中研究的新型潮流能发电系统由自适应双向流水平轴定桨距潮流能透平、直驱永磁发电机、功率变换器、蓄电池储能系统以及卸荷负载组成。根据我国潮流能特点和直驱永磁发电系统的运行特性,采用翼型尾翼完成透平的双向潮流对流功能。针对离网型潮流能发电系统的功率控制,设计了基于三相不可控整流桥和双管BUCK-BOOST变换器的功率变换电路。基于Matlab/Simulink软件对20 k W潮流能发电系统各部分进行了建模与仿真分析。在实海况环境进行了现场试验。研究表明,设计的离网型水平轴潮流能发电系统能够有效地利用双向潮流能,而且在结构设计方面所采取的措施提高了系统的可靠性。     

新型海流能发电控制系统设计

新型海流能发电装置控制系统是基于MPPT理论,增加了最大功率捕获控制及直流电路稳压控制,通过数学模型模拟海流速度及发电机电磁力矩,并在Matlab/Simulink环境下进行系统的搭建和仿真研究。其结果表明在实际输出功率对最大功率的比值基本相同,该系统实现对最大功率捕获,并在直流母线后端电压基本稳定,验证控制系统设计的有效性。通过搭建试验平台,对该发电系统进行试验研究。记录数据拟合曲线与理论公式曲线一致,且实现电压也在合理的波动范围,试验结果证明该控制系统正确,可进一步示范应用。     

A Simulation Model for the Evaluation of the Electrical Power Potential Harnessed by a Marine Current Turbine

This paper deals with the development of a Matlab-Simulink model of a marine current turbine system through the modeling of the resource and the rotor. The simulation model has two purposes: performances and dynamic loads evaluation in different operating conditions and control system development for turbine operation based on pitch and speed control. In this case, it is necessary to find a compromise between the simulation model accuracy and the control-loop computational speed. The blade element momentum (BEM) approach is then used for the turbine modeling. As the developed simulation model is intended to be used as a sizing and site evaluation tool for current turbine installations, it has been applied to evaluate the extractable power from the Raz de Sein (Brittany, France). Indeed, tidal current data from the Raz de Sein are used to run the simulation model over various flow regimes and yield the power capture with time.