Cascaded H-bridge SVG control based on feedback linearization control

Because the mathematical model of cascaded H-bridge SVG(Static Var Generator) in the synchronous rotating dq coordinates system is multivariable, nonlinear and strongly-coupled, the nonlinear state feedback transformation is applied to linearize the state feedback of SVG for making it a linear system to decouple its active and reactive components. The mathematic model of SVG system is first checked if the necessary and sufficient conditions for its precise linearization in the state space are satisfied. If they are satisfied, the output function is then determined to precisely linearize the current-loop of SVG in the state space and analyze the system stability. A MATLAB simulation model and a 10 kV experimental prototype are built to verify the steady-state and dynamic performances of control strategy. Results show that, with the proposed control algorithm, the reactive power compensation of SVG has higher precision, better steady-state performance and quicker dynamic response.