Abstract: In the practice of robust control of grid connected multilevel inverters, the output voltage fluctuation amplitude of the inverter is relatively large, and the harmonic distortion rate is relatively high, resulting in poor robust control effect. A research on robust control of grid connected multilevel inverters based on harmonic elimination method SHEPWM is proposed. Based on the theory of harmonic elimination SHEPWM, a mathematical model of harmonic elimination SHEPWM is established from both unipolar and bipolar perspectives. Using the Wu method to solve the mathematical model of the harmonic elimination method SHEPWM, optimizing and controlling the switching angle parameters of the inverter, eliminating harmonics in the output voltage, improving the robustness of the inverter, and achieving robust control of the grid connected multilevel inverter based on the harmonic elimination method SHEPWM. Experimental results have shown that under the application of the design method, there is no significant ripple in the output voltage of the grid connected multilevel inverter, and the harmonic distortion rate does not exceed 1%. This can achieve robust and effective control of the grid connected multilevel inverter, effectively improve system stability, and enhance inverter robustness.