A mathematical model of a voltage source converter is presented in the synchronous reference frame for investigating VSC-HVDC for transferring wind power through a long distance. This model is used to analyze voltage and current control loops for the VSC and study their dynamics. Vector control is used for decoupled control of active and reactive power and the transfer functions are derived for the control loops. In investigating the operating conditions for HVDC systems, the tuning of controllers is one of the critical stages of the design of control loops. Three tuning techniques are discussed in the paper and analytical expressions are derived for calculating the parameters of the current and voltage controllers. The tuning criteria are discussed and simulations are used to test the performance of such tuning techniques.reviewe
