Investigation of the impact of embedded VSC-HVDC active and reactive power control on power system stability

Increasing demand for long-distance high-power transmission and advances in Voltage Source Converter technology create a case for embedded VSC-HVDC transmission solutions. Numerous aspects have to be considered in order to fully understand the influence of embedded VSC-HVDC links on inter-area transfer capability. This paper focuses on the influence of embedded VSC-HVDC on power system stability. Maximum transfer capability of a long corridor connecting two synchronized areas and subjected to a permanent fault is used as an indicator to tune the design and operation parameters of the HVDC link and provide a comparison with alternative AC reinforcement of the corridor. The investigation is carried out first on a simple radial test system and then up-scaled to a case study on the modified IEEE 39-bus test system. The study is performed using generic VSC controller design and positive-sequence RMS simulations with the software DIgSILENT PowerFactory.