IMPACT OF POWER QUALITY ON ASYNCHRONOUS MOTOR PERFORMANCE: A DYNAMIC MODEL APPROACH

Abstract

The paper presents an advanced dynamic electromagnetic model of a three-phase squirrel-cage asynchronous motor designed to simulate performance under real-world power quality disturbances. The motivation stems from the growing need to address electromagnetic compatibility issues and energy losses in industrial systems exposed to asymmetric voltages and harmonic distortion-conditions common in environments with nonlinear loads such as welding equipment, arc furnaces, and frequency converters.

Conventional motor models, typically assuming ideal supply conditions, are inadequate for predicting performance degradation due to poor power quality. To overcome this, the proposed model utilizes space-time complexes and an extended version of the Park-Gorev equations. A key innovation is the introduction of nonlinear magnetic saturation, modeled via a polynomial relationship between mutual inductance and the magnetizing current. This feature enables a more accurate representation of core material behavior under high-load or unbalanced conditions.

The simulation was conducted for an MTKH 112-6 asynchronous motor rated at 5.3 kW under two scenarios: (1) ideal sinusoidal three-phase voltage, and (2) real distorted voltage with significant asymmetry and harmonic components up to the 10th order. The analysis revealed that even moderate distortions led to increased stator and rotor losses (from 491.3 W to 498.3 W and 652.2 W to 661.5 W, respectively), a drop in overall efficiency (from 81.4% to 81.2%), and a marked reduction in power factor (from 0.98 to 0.90). Furthermore, current waveform analysis showed visible harmonic deformation, and torque pulsation diagrams indicated increased electromagnetic stress on the motor structure.

The proposed model demonstrated a high degree of agreement with experimental data (RMSE < 4%), validating its applicability for use in diagnostics, predictive maintenance, digital twin platforms, and educational simulation environments. Unlike Fourier-based harmonic analysis, the use of space-time complexes allows the system to be modeled holistically, capturing transient behavior and steady-state responses without needing individual harmonic decomposition.

This work contributes to the broader field of smart manufacturing and energy-efficient industrial automation. Future improvements include incorporating stochastic modeling to account for dynamic grid variations, enabling probabilistic forecasting and automated control strategies within Industry 4.0 frameworks.

Keywords: asynchronous motor, power quality, dynamic model, voltage asymmetry, harmonic distortion, electromagnetic simulation, efficiency.