On Integration of Wind Power into Existing Grids via Modular Multilevel Converter based HVDC Systems

Abstract

Due to the advent of advanced solid-state power devices and converters, it is now promising to transmit huge quantities of renewable energies to the main electrical grids. One of the major renewable energy resources is the wind power plant, which has the benefits of very low generation cost, simple infrastructure, lesser operating staff, lesser erection times, and negligible environmental pollution. Various far located power stations, including offshore and mainland wind power plants, as well as big industrial loads can be joined together with the existing AC grids by implementing multiterminal HVDC transmission systems. This recently established strong feature of HVDC systems is making them more feasible for future grids. The current source converter (CSC) is an established topology used in HVDC systems, worldwide. Rigorous research is being carried out on the voltage source converters (VSCs), especially on Modular Multilevel Converters (MMCs) based HVDC systems that are distinguished by their benefits of lower harmonics, lower maintenance, almost absence of bulky DC link capacitors and AC filters, black start capability, smooth control of powers, and addition of renewable energy using DC cables with the prevailing AC grids. In this paper, technical features associated with wind power plants and the interconnection of such plants via new MMC based HVDC systems with the present AC grids are discussed in detail. Mathematical modeling and performance analysis of advanced MMC technology is carried out by performing simulations in Matlab/Simulink ® . The deduced technical outcomes remarkably show the effective use of this converter in the near future grids.