Analysis and Control of Wind Farm Incorporated VSC-HVDC in Unbalanced Conditions

With increasing attention to sustainable development and environmental protection, more and more countries turn to wind energy to reduce their dependence on traditional fossil fuel energy. Among the new challenges with this trend is how to integrate wind farm with existing AC network more effectively. The paper presents a possible measure based on VSC-HVDC, namely so-called wind farm incorporated VSC-HVDC (WVSC-HVDC). In the paper the wind farm along with an AC grid supplies to a passive network. The paper firstly introduces VSC-HVDC, and then presents a space vector based control strategy for supplying to a passive network. The rectifier controls DC voltage and reactive power that is needed by the wind farm. The inverter controls the AC bus voltage in the passive network. Simulations using PSCAD/EMTDC are performed to study the steady and transient behaviors of WVSC-HVDC. With harmonics analysis, the simulation results will be helpful for further understanding of the operation characteristics of WVSC-HVDC and its protection design