Electrical, Electronics and Control notations and conventions

This page provides a list of the most common notations in the electrical, electronics and control notations.

• Frequencies should be named f
• Currents should be named i (for complex variable), I (for absolute value) or id/iq for dq-axis values
• Voltages (phase-to-phase) should be named u (for complex variable), U (for absolute value) or ud/uq for dq-axis values
• Voltages (phase-to-ground) should be named v (for complex variable),V (for absolute value) or vd/vq for dq-axis values
• Apparent power should be named s (for complex variable) or S (for absolute value)
• Active power should be named P, reactive power should be named Q
• Impedance should be named Z, resistance should be named R, reactance should be named X, admittance should be named Y, conductance should be named G, susceptance should be named B
• Angles should be named according to their name in textbooks (ex: theta)
• Time should be named t (T is used for the temperature).
• *,° are used for setpoint values
• s is used for the transfer functions