Final answer:
Overvoltage protection circuits in aircraft power supply systems protect against excessive voltage levels that could damage electrical components.
Step-by-step explanation:
Overvoltage protection circuits in aircraft power supply systems are designed to protect the electrical components and systems from excessive voltages that could cause damage.
These circuits can include components such as surge arrestors, transient voltage suppressors, and voltage regulators, which help limit the voltage levels within safe operating limits.
For example, a surge arrestor can divert excess voltage to a ground or an external circuit, preventing it from damaging sensitive equipment.