Research And Simulation Of Control Algorithm For Three-level Inverter

Power-hungry and environmental deterioration become more and more obviously,how to improve the power efficiency is a problem and all countries pay attention to this roblem.Three-level inverter can reduce the electricity’s wear and tear of the high voltage and high-power moter obviously,at the same time,it can also improve the power efficiency obviously,so there are a lot of scientific researcher pay close attention on it,especially Three-level inverter’s control method.This paper narrate how the two-level inverter work and two-level SVPWM symmetrical modulation model control algorithm’s basic step in detail,after that according to the parallelogram rule of vector synthesis inferred a new two-level SVPWM algorithm based the ripe traditional two-level SVPWM symmetrical control algorithm,this algorithm just need calculate how long the reference vector’s relevant vector are in action when the reference vector is in the first sector,then when the reference vector is in the other sector which relevant vector’s work time can be easily calculated.Then this paper take the Diode-clamped three-level inverter for example,narrate the principle of operation of the three-level inverter and the basic step of three-level SVPWM vector decomposition algorithm in detail.Then use this new two-level SVPWM algorithm and three-level SVPWM vector decomposition algorithm in the three-level,a new three-level SVPWM algorithm is inferred. This new algorithm can calculate how long the relevant vector in action just according to the first small sector of the first big sector’s relevant vector calculation formula even if the reference vector is in three-level plane any area. At the same time,build the simulation model of the traditional two-level SVPWM symmetrical algorithm, the new two-level SVPWM algorithm,three-level SVPWM vector decomposition Algorithm and the new three-level SVPWM algorithm in MATLAB/Simulink,the simulation result indicated that the new wo-level SVPWM algorithm and the new three-level SVPWM algorithm is correct.Lastly,designed PMSM double-ring vector control system and build the simulation model in MATLAB/Simulink, the simulation result indicated that this control system have fast speed of response and good static and dynamic feature.