Electrical Protection

Electrical Energy is

Generated at few kV and stepped up.

Transmitted through AC and HVDC lines.

Stepped down and distributed at load centers.

Its natural mode of synchronous operation knits the system together.

Why do we need protection?

Electrical apparatus operates at various voltage levels and

may be enclosed or placed in open. Under abnormal

operating conditions protection is necessary for

Safety of electrical equipments.

Safety of human personnel.

Types of Protection

Apparatus Protection:-

Transmission Line Protection
Transformer Protection
Generator Protection
Motor Protection
Busbar Protection

System Protection:-

Out-of-Step Protection

Under-frequency Relays

Islanding Systems

Rate of Change of Frequency Relays