Switchgear

For the auxiliary and protection system for the plant, they need supplies to be in 6.6kV/AC, 415V/AC, 220V/DC, 24V/DC and 220V/AC. All this supply will come from the generation of the plant it’s own. Therefore it needs the switchgear system to arrange and distribute all the supply to the devices accordingly.

This switchgear system also connected to the black start diesel and emergency diesel generators. These two generators are used when there are emergencies like system trip or suddenly lost of supply. During these situations, the emergency generator will automatically cut in and supply 415V to the 415V feeder bus, and the operator will need to manually switch on the black start diesel generator manually to supply 6.6kV to the feeder.

GT and ST single line diagram

Before going into detail of electrical knowledge, the basic flow of this plant is necessary for us to study. The first drawing that we are exposed to is the single line diagram of Gas turbine generator and steam turbine generator.





For both gas turbine and steam turbine generator single line diagram, they are having the same concept of electrical flow. First the generated power is 10.5kV which will be stepped up to 275kV then send to national grid. At the same time, the generated voltage will then stepped down for the excitation system and the gas turbine control supply.



Later this single line diagram will be further connected to the switchgear drawing and switchyard connection.

Electrical Department

Entering the seventh week of training (16 MAY 2010), I am now in the electrical department. Being the first day in this department, everything seems to be nice. The manager and engineer are friendly and willing to share knowledge to us. Since I am an electrical power student, I can’t wait to learn the practical things about my course.





Firstly we are asked to follow the workers to the workshop, and luckily during the first day we already had the opportunity to follow the workers for a switchgear and motor maintenance. This maintenance is taken to make check the motor supply balancing, the insulation of the connection and also the physical neatness of the motor and switchgear.