A Practical Approach to Controlling the Back-to-Back Voltage Source Converter System

This paper presents a new approach for the modeling and dynamic control of the back-to-back systems which are based on voltage source converters. The state-space average method is used to derive the non-linear model of the system. Through a non-linear transformation and power balance fact a linear model for the system is developed. It is shown that DC link of the system can be regulated only from the supplier side and not from both sides which is adopted to the new market structure in the liberalized power systems and the mathematical approach is given. The decoupled controller is designed based on the state feedback method and the proposed model is validated through the comparison of the average and switching model simulations. The system performance is studied under different normal and fault cases.