PROJECT TITLE :

Active Voltage Feedback Control for Hybrid Multiterminal HVDC System Adopting Improved Synchronverters

ABSTRACT:

In this paper, we propose an idea to integrate a lot of renewable energy into the present China power grid and to supply remote islands with a reliable power offer. The idea is to expand the present purpose-to-purpose line-commutated converter (LCC) HVDC transmission link into a hybrid multiterminal HVDC (hybrid MTDC) system, which contains LCC stations and voltage-supply converter (VSC) stations. Accordingly, this paper proposes a novel control strategy for this method referred to as active voltage feedback management, which will not need any high-speed communication system below numerous disturbances, like wind speed variations, load fluctuations, faults, etc. This paper conjointly adds secondary frequency regulation to the synchronverter, which is one means of combining the VSC converter with synchronous machine behavior. Then, this paper applies an approach to limit its current below fault conditions. Finally, the complete hybrid MTDC system is modeled in PSCAD/EMTDC. Simulation results show that the improved synchronverter is able to attain secondary frequency management, and therefore the presented active voltage feedback management works very well when exposed to varied disturbances.