Self excited induction generator

A Self-Excited Induction Generator (SEIG) is a type of induction machine that can operate as a generator without an external power source

Basic Working Principle

• A standard squirrel-cage induction motor is driven above synchronous speed using a prime mover (e.g., wind turbine, diesel engine).
• Capacitors connected to the stator terminals supply the magnetizing current.
• Residual magnetism in the rotor starts the voltage build-up.
• Once voltage builds up, the capacitors maintain the excitation by supplying reactive power.

🧩 Circuit Configuration

🔹 Components:

• 3-phase induction machine (motor)
• Capacitor bank (usually delta connected)
• Prime mover (mechanical input)
• Load (resistive or inductive)

🔹 Equivalent Circuit (per phase):

Similar to a motor, but:

• Capacitors added at the stator terminals
• No external supply

⚡ Conditions for Voltage Build-up

1. Presence of residual magnetism in rotor
2. Sufficient capacitor value to supply the reactive power
3. Load must not draw excessive reactive power