软岩变形合理值
allowable deformation of soft rock
瑞利C里兹变分法
Rayleigh-Ritz variational procedure
瑞利–里兹变分法
Rayleigh-Ritz variational procedure
三电平变频调速系统
Three-level Adjustable Speed Drive System
3-LEVEL INVERTER-MOTOR SYSTEMS
three-level inverter-motor system
三电平弧焊逆变电源
three-level invert welding supply converter
三电平逆变电路
three-level inversion circuit
三电平逆变器拓扑
three-level inverter topology