SMES-DFIG提高多机系统暂态功角稳定性的控制策略

Control Strategy of SMES-DFIG for Improving Transient Power Angle Stability of Multi-machine System

为了提高风电并网系统暂态功角稳定性,以双馈风力发电机(doubly fed induction generator, DFIG)并联超导储能(superconducting magnetic energy storage, SMES)装置为研究对象,提出了一种联合SMES-DFIG的控制方法。通过风电场接入对系统节点导纳矩阵的修正和收缩处理,并基于拓展等面积等则,依据接入DFIG的网络拓扑和暂态期间系统等值功角变化的信息,分析系统等值机械功率改变量的增减性质对系统功角的影响关系,对与DFIG并联的SMES给出了提高系统暂态功角稳定性的功率输出综合控制规律,并对控制策略的有效性进行了仿真验证。研究结果表明,合理准确地控制SMES的功率输出可以改善系统等值功角的变化,加快系统稳定的恢复速度,该研究结果可为利用SMES提高多机系统暂态稳定性的控制提供参考。

In order to improve the transient power angle stability of a wind power grid-connected system, the doubly fed induction generator(DFIG) parallel with superconducting magnetic energy storage device(SMES) is taken as research object, and a control method of joint SMES-DFIG is proposed. Through modifying and shrinking the node admittance matrix of system connected to wind farm, the relationship between the increase and decrease of equivalent mechanical power change and the power angle of system is analyzed based on the extended equal area criterion, the network topology connected to DFIG, and the information of equivalent power angle change of system during the transient period. Moreover, a power output control rule for SMES in parallel with DFIG is given to improve the stability of the transient power angle of system. The effectiveness of the control strategy is verified by simulation. The research results show that reasonable and accurate control of the power output of SMES can improve the change of equivalent power angle of system and accelerate the stable recovery rate of system. The research results can provide a reference for the control of using SMES to improve the transient stability of multi-machine system.