### Aim of the study element

To teach students to characterise non-linear circuit and use sinusoidal analysis, to understand  transition processes, apply nodal analysis and conduct variable current circuit investigation or design.

Learning outcome

Having successfully completed this element you will be able to:

• Successfully analyse nonlinear circuits of constant and variable currents.
• Analyse and design magnetic circuits, to understand the impact of magnetic components, and make calculations of their parameters.
• Use already known basics about circuits from the first module to create complex circuits with magnetic and nonlinear effects.
• Analyse and characterise transient responses of a circuit with complex mathematical tools.
• Understand functions of the circuit components like filters, transformers and others.
• Measure and calculate circuit properties and characteristics.

Covered topics

• Nonlinear DC electric circuits.
• Magnetic circuits.
• Nonlinear AC electric circuits.
• Transient processes in nonlinear electric circuits.
• Electric circuits with variable parameters.
• Sinusoidal and network analysis.
• Two-point networks.
• Complex frequency.

## Complex conductance. Active and reactive power

Complex conductance Y is the value, reverse to the complex resistance Z, where Y=1Z=ye-jφ. Complex conductance is measured with Siemens (1Ohm), Y=1R+jX=R-jXR2+X2=RR2+X2-j XR2+X2. Ohm Law’s using the conductivity…