中压固态切换开关装置的研究

文中对中压固态切换开关(SSTS)进行了设计。利用兼具实时性和可靠性的dq变换法进行电压暂降检测,将滤除交流分量后的dq轴有效值与电压暂降阈值进行比较来产生切换指令。分析了过零切换和强迫切换策略的特点,采用根据主电源馈线电流方向与主备电源电压差方向控制备用晶闸管的触发,从而快速地将敏感负载切换至备用电源的方法。利用PSCAD建立了10 k V固态切换开关的仿真模型,对dq电压检测法的快速性和可靠性以及强迫切换控制的有效性和可行性进行了验证。

Research on Medium-Voltage Solid State Transfe Switch

A medium voltage Solid-State Transfer Switch (SSTS) has been designed in this paper. A dq transformation based method with both timeliness and reliability is deployed to detect voltage sag, by subtracting the AC components from the dq values of voltages, the RMS value of the remaining part is compared with a pre-set voltage threshold to generate transfer command signal. BBM and MBB switching strategies are compared and analyzed, and MBB switching strategy, which triggers thyristor according to the current direction on primary feeder and voltage drop direction between preferred and alternate sources, is utilized to shorten the transfer time, so sensitive loads can be transferred to alternate source very fast. A 10kV SSTS simulation model is established using PSCAD and simulation results verify the instantaneity and reliability of dq voltage detection method and the effectiveness and feasibility of MBB switching strategy