Classification Of Diesel Generator Sets In Nuclear Power Station Applications

In order to make the nuclear power plant shut down safely when the power grid is cut off unexpectedly, and to ensure that the emergency diesel generator set must start to generate electricity immediately within the specified time in case of earthquake, hurricane, air crash and other accidents that cause water loss in the primary circuit of the nuclear reactor. There are many types of diesel generator sets, which can be divided into nuclear safety class, hydraulic test pump, auxiliary, emergency command center, security control center, mobile diesel generator set, etc. according to the application form of nuclear power plant.

(1) Nuclear safety diesel generator set.

The nuclear safety level diesel generator set is Class 1E (safety level) equipment. In case of external power failure, EDG will immediately start power generation to provide emergency power supply for the safety protection, cooling, heat dissipation, ventilation and other systems of the nuclear reactor. Perform relevant nuclear safety functions.

(2) Hydraulic test pump diesel generator set.

The diesel generator set of the hydraulic test pump is a non Class 1E (non safety class) equipment. When the accident condition exceeds the design basis, LLS can automatically start and provide emergency power to the hydraulic test pump through the control cabinet in the hydraulic test pump to ensure water supply to the No. 1 shaft seal of the main pump, so as to ensure the integrity of the reactor coolant system. It is also responsible for supplying power to the emergency ventilator of the meter and hydrostatic test pump room required for unit operation.

(3) Auxiliary diesel generator set.

The auxiliary diesel generator set is non Class 1E (non safety class) equipment. In case of an emergency (power loss of the whole plant) and two nuclear class units cannot be put into operation, AAC class units must be put into operation quickly to provide sufficient and reliable power for loads related to safe shutdown, ensure the cooling of the reactor core and the removal of residual heat, and ensure the proper integrity of the containment.

(4) Diesel generator set of emergency command center.

The diesel generator set in the emergency command center is non 1E (non safety level) equipment, which is used to provide stable and reliable backup power for important systems in the EM building at ordinary times or in the event of nuclear power plant accidents. It is one of the important equipment for normal operation of process equipment and for ensuring the habitability of the building.

(5) Diesel generator set of security control center.

The diesel generator set in the security control center is a non 1E (non security level) equipment. Under normal conditions, the diesel generator set is in standby state. When the normal power supply is lost, the diesel generator set will automatically start quickly, and reach the rated frequency and rated voltage in about 10s. The main switch is closed to provide power for the relevant loads in the security control center.

(6) Mobile diesel generator set.

The mobile diesel generator set is an improvement plan proposed by the National Nuclear Safety Administration after the Fukushima nuclear accident. Each nuclear power station shall be equipped with at least one medium voltage 6.6kV mobile diesel generator set and one low voltage 0.4kV mobile diesel generator set. In case of failure of various fixed emergency diesel generator sets in front of them under accident conditions beyond the design basis, these two diesel generator sets can provide sufficient and reliable power for relevant loads required for safe shutdown, ensure the cooling of the reactor core and the removal of residual heat, and ensure the integrity of the containment.

Guangxi Dingbo Generator Set Manufacturing Co.,Ltd. has a young and professional technical backbone team, with an average working age of more than 10 years in the generator unit industry. There are 24 sales and service departments throughout the country to provide users with a one-stop service of machine room design, equipment supply, commissioning and maintenance at any time. No matter when and where, a well-trained service team will provide you with comprehensive and considerate protection. For more details, please contact us with sales@dieselgeneratortech.com.