DC bus overvoltage protection circuit and element parameter configuration method

The invention discloses a direct-current bus overvoltage protection circuit and a component parameter configuration method, two load resistors R1 and R2 are arranged in the direct-current bus overvoltage protection circuit, the R1 independently bears overvoltage protection of a direct-current bus of a wind turbine generator in a large-load working mode, and the R1 and the R2 are both put into operation in a small-load operation mode. According to the invention, parameters of different load resistors are accurately calculated based on the balance between wind energy captured by a wind turbine and wind turbine generator rotor storage energy and/or DC capacitor storage energy, grid-side converter transmission energy and DC voltage protection circuit consumption energy; the problem of fault ride-through failure caused by frequent buffeting of the voltage of the direct current bus and overvoltage of the direct current bus or galloping of the rotating speed of the unit under extreme conditions is solved, the proble