Effect of Symmetrical Voltage Sag on Induction Motor Considering Phase-Angle Factors Based on a New 2-D Multi-Slice Time-Stepping Finite Element Method

Abstract

Voltage sag is one of the most common power quality disturbance in industry, which causes huge inrush current and inrush torque of induction motors, and has serious impacts on the safe and stable operation of induction motor. To further study the detailed transient characteristics of induction motors during sag events, an improved 2-D multi-slice field-circuit-motion coupling time-stepping finite element method (FEM) is proposed. Then, taking a 5.5 kW, a 55 kW and a 135 kW induction motors as examples, the influence of phase-angle jumps and initial point-on-wave on the stator current peak, torque peak, speed loss and critical clearing time of the induction motor are discussed by using the proposed model. The simulation results show that stator current peak and torque peak increase obviously, while speed and critical clearing time decrease apparently, when considering the phase angle jump. And different initial points have little influence on these operation indicators. Finally, the proposed method is verified by comparing the measured and calculation data of the 5.5 kW three-phase squirrel-cage motor, respectively. The results show that the proposed method can reach higher precision with considering nonlinear characteristics.

2D Finite Element Analysis of Asynchronous Machine Influenced Under Power Quality Perturbations

“…This method provides only steady-state motor parameters and cannot be used for the analysis of transient regimes. Time-stepping finite element method is the representation of the time derivative of the magnetic vector potential for each time step and can be used for the analysis of both transient and steady-state [18]. In both methods, the discretization of the problem over the plane of the machine's cross-section using FEM results in the system of linear equations written form as follows;…”

Static Eccentricity Fault Analysis of Surface-Mounted Permanent Magnet Electromotor with Skewed Slots Based on 2D FEA

“…The algorithm is based on two-dimensional finite element method, which is not only accurate, but also easy to model, with less computation. As shown in Figure 2, the ideology is to divide a skewed electromotor into several sections along the axial direction and treat each section as an independent unit [25][26][27][28]. In the figure, the thick blue line represents the original whole conductor in the skewed slot, and the thick red line segments represent the equivalent straight conductor.…”