An Improved Feedback Linearizing Control Scheme for Three-Phase Voltage-Type PWM Rectifier

In this paper, the linear mathematical model of three phase Voltage Source Rectifier (VSR) in d-q coordinates is deduced based on the power balance equation and decoupled state-feedback control method. An improved control strategy using current inner loop with state feedback decoupling, voltage square outer loop and SVPWM modulation is proposed. Nonlinear input transformation is used to derive a linear model from the original nonlinear model. The advantages of the proposed scheme include accurate controller design, fast dynamic response and high quality of current and voltage waveforms. SVPWM modulation can reduce the total harmonic distortion (THD) of the grid side current. The whole system is modeled and simulated by using the MATLAB/SIMULINK software. Simulation results shows that the proposed PWM model can give satisfactory steady-state characteristics and fast transient response, and it is simple to tune parameters.