面向“碳达峰、碳中和”目标，发展半波长输电技术可为构建以新能源为主体的新型电力系统提供能源保障。半波长技术因其输电距离远、经济性好等独特优势，在“西电东送”能源战略中有较好的应用前景。针对输电线路自然长度不足工频半波长现象以及固定调谐的不足，文章提出一种变阻抗型可控调谐方法，基于可控串补(thyristor controlled series compensator, TCSC)阻抗控制策略构造可微调的调谐电感，基于电容三级投切策略构造可分级的调谐电容。对可控调谐可行性、故障过电压特征以及串补过压抑制进行仿真分析。结果表明，可控调谐能够消除电气长度误差，使线路保持半波长特性，线路补偿效果与可控调谐长度相关。
英文摘要:
Facing the goal of emission peak and carbon neutrality, the development of half-wavelength transmission technology can provide energy guarantee for the construction of novel power system with high proportion renewable energy. Half-wavelength technology has a good application prospect in the energy strategy of "West-East power transmission" because of its unique advantages, such as long transmission distance and good economy. Aiming at the problem that the natural length of transmission line is insufficient to half-wavelength of power frequency and the drawbacks of fixed tuning methods, this paper proposes a controllable tuning method, based on TCSC impedance control strategy and three-stage switching strategy, tuning inductor and capacitor are designed. Furthermore, we analyzed the feasibility of controllable tuning, fault over-voltage characteristics and TCSC overvoltage limitation. The simulation results show that the controllable tuning network can eliminate electrical length error and keep the line half-wavelength characteristics. The compensation effect is related to the controllable tuning length.