Modulation method and system compatible with multiple three-level topologies

The invention discloses a modulation method and system compatible with various three-level topologies, and belongs to the technical field of power electronic converter modulation. Comprising the following steps: sampling an electric signal of a three-level topology type signal generation circuit to judge a three-level topology type; the output state of the three-phase bridge arm is obtained through a grid-connected algorithm; and when the output state of the three-phase bridge arm changes, obtaining a start-up operation pulse sequence by querying a preset state switching table and a preset pulse sequence table. According to the invention, the modulation mode in the DSP program is decoupled from the specific three-level topology, and the maintainability of the program is improved. And the architecture of the FPGA program has universality and high expandability. The modulation function of the three-level topology is highly abstracted, when a new topology or a new PWM modulation mode needs to be added, only info