Influence of Stator Inner Turn Short Circuit on Electromagnetic Exciting Force of Variable Speed Pump Storage Motor
This paper investigated the electromagnetic excitation force characteristics on the armature winding in a variable-speed pumped storage machine(VSPSM)in normal and stator interturn short circuit fault(SISC)cases.Firstly,the theoretical formulas for the air gap magnetic flux density and electromagnetic excitation force were derived when a sta-tor winding inter-turn short circuit fault occurred in the VSPSM.Then time-stepped finite element models(FEA)were established for the motor in normal and SISC cases.The electromagnetic excitation force was computed for various de-grees of short circuit severity.The distribution characteristics of the electromagnetic excitation force in the spatiotemporal domain were extracted by utilizing the discrete Fourier decomposition.The theoretical derivations accorded with simula-tion results and test the doubly-fed prototype.The results indicate that after the stator turn short circuit fault occurs in variable speed pumped storage motor,its electromagnetic excitation force will produce the short circuit features time-space harmonics with(0±x)order/0 frequency doubling,(14±x)order/2 frequency doubling order(x=1,2,…),and the degree of short circuit is positively correlated.
VSPSMSITSCelectromagnetic excitation forceshort-circuit testfinite element
万方数据
维普
