Series compensation is generally used with long transmission lines to increase power transfer through the line and to enhance system stability. In the case of voltage source converter-based series flexible AC transmission system (FACTS) controller, an energy storage device can be incorporated at the DC bus which further improves control of real and reactive power flow. However, four-quadrant operation of FACTS controllers with energy storage device poses new challenges for the operation, control and protection of power system. Most commonly used protection scheme for long transmission lines, the distance relay, may not be reliable in case of lines compensated with series FACTS controllers. This paper proposes a new wavelet transform-based relay logic for fast and reliable detection, and classification of faults in a hybrid series-compensated long transmission line incorporating a passive series capacitor and static synchronous series compensator with energy storage device (SSSC-ES). The proposed relay logic is also able to accurately estimate the location of fault, and a wavelet transform-based boundary condition is used to discriminate between internal and external faults. It is shown through various simulation case studies that the four-quadrant operation of SSSC and fault resistance have negligible impact on the performance of the wavelet transform-based relay.

中文翻译：

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基于小波变换的带储能装置的SSSC输电线路保护

串联补偿通常用于长传输线，以增加通过线路的功率传输并增强系统稳定性。在基于电压源换流器的串联柔性交流输电系统 (FACTS) 控制器的情况下，可以在直流母线处并入一个储能装置，进一步改善对有功和无功功率流的控制。然而，带有储能装置的 FACTS 控制器的四象限运行对电力系统的运行、控制和保护提出了新的挑战。最常用的长输电线路保护方案，距离继电器，在使用 FACTS 系列控制器补偿线路的情况下可能不可靠。本文提出了一种新的基于小波变换的中继逻辑，用于快速可靠的检测，包含无源串联电容器和带有储能装置的静态同步串联补偿器 (SSSC-ES) 的混合串联补偿长输电线路中的故障分类和故障分类。所提出的继电器逻辑还能够准确地估计故障的位置，并使用基于小波变换的边界条件来区分内部和外部故障。通过各种仿真案例研究表明，SSSC 的四象限操作和故障电阻对基于小波变换的继电器性能的影响可以忽略不计。基于小波变换的边界条件用于区分内部和外部故障。通过各种仿真案例研究表明，SSSC 的四象限操作和故障电阻对基于小波变换的继电器性能的影响可以忽略不计。基于小波变换的边界条件用于区分内部和外部故障。通过各种仿真案例研究表明，SSSC 的四象限操作和故障电阻对基于小波变换的继电器性能的影响可以忽略不计。