Research Of Model Predictive Control For PWM Rectifier

PWM rectifier has been widely used in electric power, energy, transportationand so on, because of its features of unity power factor, stability to keep DC voltageand bidirectional energy flow. Fast response capability of current loop is required inhigh-power applications. This paper focus on the application of model predictivecontrol (MPC) in power electronics system to improve the performance of thesystem.This paper firstly presented the architecture of PWM rectifier, thenmathematical model was established under abc coordinate and dq coordinate. Themodel was validated according to the law of conservation of energy. The spacevector pulse width modulation and its implementation methods were introduced.The principle of model predictive control algorithm was analyzed. Three predictivecontrol strategy: predictive control algorithm based on the state-space model,dynamic matrix algorithms based on the step response model and generalizedpredictive control theory were introduced. In order to make application to electricsystem, the predictive control algorithm must be simplified, and this paperpresented some method to simplify the algorithm. Besides, the affects of the mainparameters to predictive algorithm was also analyzed. At last，predictive controlmethod was introduced into the PWM rectifier current loop, which can pre-calculatethe system behavior and choose an optimal value of control variables.Matlab/Simulink was used to verify the predictive algorithm, and anexperimental platform was built based on dSPACE for experimental verification.Performance of MPC for PWM rectifier was evaluated compared with PI control.Both simulation and experimental results pointed out the validity and advantages ofMPC for PWM rectifier in improving the current response. At the same time, theDC voltage was stable, the THD of grid current was low, and power factor was high.