Experiences during construction and commissioning of Electrical power generation and evacuation systems in PFBR

BHAVINI, a public sector unit under Department of Atomic Energy, is responsible for construction, commissioning and operation of fast reactors in India. Prototype Fast Breeder Reactor (PFBR) capacity of 500 MWe which is in advanced stage of commissioning is the forerunner for the second stage of India's three stage nuclear programme. Starting from detailed engineering, manufacture installation, integration, till commissioning and operation of all the electrical and control & instrumentation systems, there were many challenges and surprises which have been addressed one by one in a systematic manner. This paper brings out major experiences during construction, commissioning of electrical power Generation and evacuation system in PFBR. The emergency electric power supply (Class IE) system in Nuclear Power Plant is generally categorized into three types based on the power requirements of the loads. 1. AC power supply to Auxiliaries, which can tolerate short interruption upto 3 minutes is classified as Class-III AC Emergency power supply. Under normal condition, this power supply is drawn from Class IV system and in case of class IV power supply failure, emergency diesel generators provide the back up. 2. No break AC power supply to auxiliaries derived from class-III buses through rectifier/charger and inverter with a battery backup at the input of inverter is called class-II power supply. 3. No break DC power supply to auxiliaries derived from Class-III buses through rectifier/charger with a battery backup provided at the output of the rectifier / charger is called Class-I power supply. (author)