Modular AC/DC to DC/AC Converter with Short Term Frequency Stability in HVDC

This paper deals with a real-time coordinated control strategy which control modular converter for frequency response model in power system. The existing emergency frequency control strategy is not adaptive to the varying operation conditions and may cause excessive or deficient actions, which could result in inefficient control or high risk of frequency instability. Therefore, a real-time coordinated control strategy is proposed in this study based on the online-updated frequency response model. Also, this problem is peculiar in case of HVDC systems where final received DC voltage is converted to AC voltage for domestic and industrial supply. To overcome this problem, a method of modular conversion is proposed in this project. Due to this, handling high voltage is very simple and control of the frequency is done better. Simultaneously, TCSC based bypassing scheme has been introduced in the system, in case of any critical issues in the modular converter or overall HVDC link. Embedding short-term energy storage to the system facilitates a power flow proportional to the variation in grid frequency. This is achieved using Thyristors Controller based Series Compensation (TCSC) devices. In this paper, with a combination of modular converter and TCSC based systems, a robust optimal Power management system (ROPMS) is developed for a High voltage DC systems.