Research And Design Of Cascaded Multilevel Inverter Based On The New Non-PWM

As the promotion of high-voltage large-capacity frequency converter and active power filter to a large number of applications. Multilevel inverter has been becoming hot point in current power electronics technology due to people's attention. Novel topologies and modulation strategies concerning multi-level converters are emerging continuously. As for as the width an depth are concerned, research on multilevel technique is advanced greatly.In the paper,we analyzed both the topology and the control schema of multilevel inverter. As cascaded multilevel inverter for the main study, we put forward the non-PWM control method. Then,we completed a single-phase system design of the three modules cascaded seven-level inverter, and did software simulation on cascaded multilevel inverter. At last, we got the experiment reasult of the single-phase system.In detail, the principle and features of several existing multilevel topologies are analyzed. Focused on analyzing cascaded multilevel inverter circuit working principle. And for its characteristics, a new type of non-PWM control mode was put forward, witch greatly reduced the switching frequency and avoided the power grid caused by pollution and electromagnetic interference of the traditional PWM mode.Based on the digital signal processor TMS320LF2407,we developed a cascaded multilevel converter experiment platform of non PWM. It mainly included the main circuit, the system of non-PWM control circuit, and the optimized drive circuit and the buffer circuit.Based on non-PWM control mode, doing software simulation on cascaded multilevel converter of multi-unit stack using SIMULINK of MATLAB.And got satisfactory simulation results.Based on the actual hardware circuit, doing the relevant experiments, the experimental results obtained with the theoretical analysis and simulation results are basically consistent. Experimental results show that the design hardware experimental platform and its control strategy is correct, and be able to meet the needs of furtherstudy.