超导储能系统中的电流源型变流器

论文总结了作者在超导储能（SMES）系统中电流源型变流器方面的研究工作。分析了作为SMES功率调节器的电流源型变流器的特点，介绍了所采用的两种PWM 开关策略：优化PWM 和直接电流PWM。将基于电流源型变流器的并联SMES 系统应用于提高电网的稳定性：提出一种SMES 装置在动态电力系统中的非线性鲁棒控制策略，并研制了相应的非线性鲁棒控制器；数字仿真及动模实验结果表明：采用非线性鲁棒控制的SMES 装置可显著改善输电系统动态品质和暂态稳定性。在改善用户的电能质量方面：研制了一套三端口式的采用电流源型变流器的SMES 动态电压补偿器（DVR）；建立了系统的完整电路模型，并在此基础上对缓冲吸收电路的工作过程进行了详细的仿真和实验研究；提出了一种准稳态的动态电压补偿算法；运行试验表明，系统具有良好的稳态工作和动态补偿性能。
Abstract: This paper reviews the author’s research work on the current source converter (CSC) in SMES units. The characteristics of CSC are analyzed and two kinds of PWM strategies used (the optimum PWM and the current vector PWM) are described. CSC-based SMES units can be applied for improving the stability of power systems. As a result of research, the equations of the non-linear robust control law of power systems with the SMES were obtained and corresponding controller was developed. The simulation and experimental results show that the SMES unit with the non-linear robust controller can significantly improve the transient stability of power systems. SMES units can also be used to improve the customer power quality. A line-interactive SMES DVR with CSC was developed. A complete circuit model of the system including the stray inductances and the snubber circuits of the switching devices was built, and simulations and experiments were performed to investigate voltage surges of the devices. A quasi-steady-state algorithm for compensating voltage sags was developed, and the SMES unit under control of the algorithm works well under both normal and voltage sag compensation conditions.
关键词﹕电流型变流器；超导储能；电力系统暂态稳定性；动态电压补偿；缓冲吸收电路
Keywords: CSC, SMES, transient stability of power systems, DVR, snubber circuits