Generator main protection and backup protection

Mar 18 ,2023 Site Editor

Different types of generators have different protections. For example, 30MW generator protection has: differential, time limit current break, compound voltage over current, loss of magnetism, overvoltage to trip. High temperature, overload, single-phase grounding alarm.


1. Generator main protection: change group differential (large difference), generator differential (differential), generator transverse difference.

(1) Longitudinal differential protection..

(2) interturn short circuit protection.


a. Stator winding single-phase grounding protection.

b. rotor winding grounding protection.
c. generator magnetic loss protection.


2. Generator backup protection: failure start (jump the protection of the upper level switch).

Meaning: When the generator protection action, the result is that the generator protection or switch is rejected, unable to trip stop. So to start the generator adjacent component protection, jump off the adjacent component switch. For example: the generator with a line, the generator does not jump, delay to jump the line switch.

A. Stator winding overcurrent protection caused by external short circuit.

b. Stator winding overload protection.

c. Rotor winding.

d, rotor surface overload protection.

e. Stator winding overvoltage protection.

f. Inverse power protection.

g. Out-of-step protection.

h. Over-excitation protection.
i, low frequency protection.


3. Generator.

invented by Faraday on September 23, 1831, is a motor that converts mechanical energy into electrical energy. It is usually driven by a steam turbine, water turbine or internal combustion engine. Electric energy is one of the most important energy sources in modern society. Generators are widely used in industrial and agricultural production, national defense, science and technology and daily life. Generators are divided into DC generators and AC generators. The latter can be divided into synchronous generator and asynchronous generator two kinds. The most common type of modern power station is the synchronous generator.


Get in Touch