EC3251 Circuit Analysis Notes - Anna University Regulation 2021

About EC3251 Circuit Analysis

EC3251 is a core subject for Anna University Semester 2 students, focusing on the analysis of electrical circuits. The subject covers DC and AC circuit analysis, network theorems, resonance, transients, and network topology. These EC3251 notes are designed to help you understand circuit behavior, solve problems efficiently, and build a strong foundation for advanced electrical engineering courses and exams.

EC3251 Important Topics (Unit-wise)

These are the most important unit-wise topics for EC3251 (Circuit Analysis - R2021). Practice these topics regularly to strengthen core concepts and improve exam performance.

Unit I – Basic Circuit Analysis

• Series and parallel circuits (current, voltage, power calculations)
• Equivalent resistance and voltage division
• Nodal analysis (voltage calculation)
• Mesh analysis (current calculation)
• Basic DC circuit problem solving

Unit II – Network Theorems

• Thevenin’s theorem and applications
• Norton’s theorem and equivalent circuits
• Maximum power transfer theorem
• Dual networks
• Wheatstone bridge analysis

Unit III – AC Circuits

• RL, RC, RLC circuits (analysis and calculations)
• Phasor diagrams (voltage and current relationships)
• Impedance and admittance calculations
• Power factor and power calculations
• Sinusoidal waveform analysis (RMS, average, frequency)

Unit IV – Resonance and Transients

• Series and parallel resonance
• Resonant frequency and Q-factor
• Bandwidth calculation
• Voltage and current at resonance
• Transient response of RC and RL circuits

Unit V – Coupled Circuits & Network Topology

• Mutual inductance and coefficient of coupling
• Series aiding and opposing connections
• Linear transformer basics
• Network topology (graph, incidence matrix)
• Tree, tie-set and network analysis