摘要
随着双馈风力发电系统在电网中所占比例的增大,增强风力发电系统在电网电压扰动下对转子电流的控制能力、改善机组的稳定性成为关注的焦点。本文在分析双馈电机5阶模型的基础上,提出了双馈风力发电系统转子电流自抗扰控制方案。该方案能够有效观测系统d、q轴间的交叉耦合以及电网电压扰动并加以前馈补偿,削弱了扰动因素对控制性能的影响;同时通过非线性状态误差反馈控制率抑制转子电流波动。数字仿真表明该控制系统在电网稳定时能够实现系统有功、无功的精确解耦;在电网故障时,较好地抑制电网电压扰动对转子电流影响,改善风力发电系统的并网运行能力。控制系统具有良好的动态响应性能,鲁棒性强。
Doubly,fed induction generator has received much attention as one of preferred technology for wind power generation. As its increasing capability in the whole power system, more and more scientific researchers become interested in the stability of doubly-fed induction generator. This paper analyses the 5^th model of DFIG, discusses its conventional controller-PID controller and points out the disadvantages. Then a new rotor current controller based on active-disturbance-rejection control theory is proposed to improve the dynamic response of the system under grid disturbances. Besides, this paper carries out simulation of the controller under normal condition and grid disturbances. The results show that the proposed controller can not only tune system power output precisely in normal condition but also ensure prominent reduction of rotor current ripple in order not to be disconnected. The results also prove that the approach has lots of advantages in response speed, control accuracy and adaptability. Moreover, the controller takes on good dynamic performances.
出处
《电工电能新技术》
CSCD
北大核心
2007年第3期11-14,19,共5页
Advanced Technology of Electrical Engineering and Energy
基金
教育部新世纪优秀人才支持计划资助项目(NCET-06-0246)
天津市应用基础及前沿技术研究计划重点项目(07JCZDJC09400)
关键词
双馈风力发电系统
转子电流
电网电压扰动
自抗扰控制
doubly-fed induction generator
rotor current
grid disturbances
active-disturbances-rejection controller
