Abstract: Disclosed are a method and a device for identifying full-section excavation parameters of large-section tunnel with broken surrounding rock, which is capable of solving the problem of inaccurate arrangement of blasting hole points in tunnel excavation engineering, including following steps: establishing a three-dimensional finite element model based on a blasting section design of a tunnel; performing a simulation with the three-dimensional finite element model based on blasting design parameters to obtain blasting quality parameters; selecting a group closest to a preset quality parameter from multiple groups of the blasting design parameters as target blasting design parameters, wherein the preset quality parameter is an acceptance grade standard of the tunnel; obtaining first thermal imaging information of a first hot spot of a surface to be blasted; calibrating actual hole spacing parameters based on the first thermal imaging information and the target blasting design parameters.

Abstract: A modulation method for a direct current (DC) coupling converter with less DC voltage sensors includes: obtaining a voltage modulated wave vr* and a current reference value ig* of the DC coupling converter; performing judgment on the voltage modulated wave vr* and the current reference value ig*, and determining a switch state of the DC coupling converter based on a result of the judgment; and when a DC voltage sensor of an electrolytic capacitor of an intermediate power module is removed, modulating a DC voltage sensor based on the voltage modulated wave vr* and a difference between DC voltages on electrolytic capacitors of the other two power modules. When the intermediate DC-side voltage sensor is removed, DC voltages of various modules of a converter system of a DC coupling power unit can still be balanced, and quality of a grid-connected current is not affected by a fault.