Control method of single-direct-current-source 9-level hybrid cascade inverter

The invention belongs to the technical field of control in an electric energy conversion device, and discloses a control method of a single direct current source 9-level hybrid cascade inverter. According to the method, an output voltage sampling signal and a voltage reference signal are subtracted and then sent to a voltage regulator, the generated output serves as the reference of a current regulator, an inductive current sampling signal serves as a feedback signal of the current regulator, and voltage sampling signals of two input capacitors and an S-R trigger generate signals Q1 and Q2 through a comparison link; an inductive current sampling signal generates a signal Q3 through a comparison link, Q1 to Q3 are sent to a modulation mode selection unit, the modulation mode selection unit and the output of the current regulator are sent to a modulation unit together, and finally driving signals of main power tubes S11-S14, S21-S24 and S31-S34 are obtained through a driving circuit. The method has the advantag