Simulink System Simulation for Harmonic Analysis and Filter Design

In this document, we will discuss Simulink system simulation implementation. The system configuration includes a 10kV bus with 10MVA short-circuit capacity connected through a transformer rated at 10/0.4kV, 100kVA capacity, and 5% short-circuit impedance. The transformer supplies an RL load of 50kVA with 0.9 power factor. To address harmonic currents generated by power electronic devices - specifically 5A each for 5th and 7th harmonics - we implement a 7th harmonic filter by connecting capacitors at the 400V bus that work in conjunction with the transformer. In Simulink implementation, this involves using Simscape Electrical components to model the transformer characteristics with proper impedance settings, configuring harmonic current sources with specified amplitudes and frequencies, and designing the LC filter circuit with calculated capacitor values tuned for the 7th harmonic frequency (350Hz for 50Hz systems). The simulation allows analysis of harmonic distortion reduction, voltage quality improvement, and system stability validation through FFT analysis blocks and power quality measurements.