This paper describes the study analysis performed to evaluate the available and potential solutions to control the highly increasing short circuit （SC） levels in Kuwait power system. The real Kuwait High Voltage （H...This paper describes the study analysis performed to evaluate the available and potential solutions to control the highly increasing short circuit （SC） levels in Kuwait power system. The real Kuwait High Voltage （HV） network was simulated to examine different measures at both 275 kV and 132 kV stations. The simulation results show that the short circuit currents exceed the permissible levels （40 kA in the 132 kV network and 63 kA in the 275 kV network） in some specific points. The examined measures include the a study on changing the neutral point policy, changing some lines from alternating current （AC） to direct current （DC）, dividing specific bus bars in some generating stations and applying current limiters. The paper also presents a new plan for the transmission network in order to manage the expected increase in short circuit levels in the future.展开更多
SiC MOSFET具有低导通电阻、低开关损耗、高开关频率以及优异的反向恢复特性。器件过快的开关速度,会导致严重的开关过冲、振荡和串扰。此外其短路承受能力弱,需要保护电路具备更快的响应速度,但较高的开关变化率,又使得保护电路的快速...SiC MOSFET具有低导通电阻、低开关损耗、高开关频率以及优异的反向恢复特性。器件过快的开关速度,会导致严重的开关过冲、振荡和串扰。此外其短路承受能力弱,需要保护电路具备更快的响应速度,但较高的开关变化率,又使得保护电路的快速响应与抗噪声能力难以兼顾。为确保其安全可靠工作,该文提出基于多段式电平调控的驱动与保护方法。驱动方法解决开关过程多个目标的协同优化问题,在获得较快的开关速度和低损耗的同时,有效地抑制过冲和振荡;保护方法提出了增加补偿回路的导通压降检测电路,降低了温度和负载变化对检测精度的影响,同时提出了两段式降低栅压的关断方法,增大故障检测盲区时间以降低干扰噪声影响,并采用软关断技术,抑制关断过电压。展开更多
文摘This paper describes the study analysis performed to evaluate the available and potential solutions to control the highly increasing short circuit （SC） levels in Kuwait power system. The real Kuwait High Voltage （HV） network was simulated to examine different measures at both 275 kV and 132 kV stations. The simulation results show that the short circuit currents exceed the permissible levels （40 kA in the 132 kV network and 63 kA in the 275 kV network） in some specific points. The examined measures include the a study on changing the neutral point policy, changing some lines from alternating current （AC） to direct current （DC）, dividing specific bus bars in some generating stations and applying current limiters. The paper also presents a new plan for the transmission network in order to manage the expected increase in short circuit levels in the future.
