Generator Auto Load Power Control in Power Generating Station

In Thermal power plant, Automatic Generation Control (AGC) is a system for adjusting the output power of multiple generators at different power plants, in response to load changes. Since a power grid requires load generation and closely balancing load moment by moment, frequent adjustments to the output of generators are mandatory. The balance can be predicted by measuring the system frequency; if it is rises, more power is being generated than used, which causes all the machines in the system to rise and accelerate. If the frequency of the system is decreasing, more supply of load is on the system than the instantaneous generation can provide, which causes all generators to slow down Load following power plants run during the day hours and early evening. They either shut down or greatly minimize the output during the night and early morning, when the demand for electricity is the lowest. The exact hours of operation depend on various factors. One of the most necessary factors for a particular plant is how efficiently it can convert fuel into electricity. The most efficient plants, which are almost invariably the less cost to run per kilowatt-hour produced, are brought online first. As demand increases, the next most efficient plants are brought on line and so on. The status of the electrical power grid in that particular region, especially how much is the capacity of base load generation. It has, and the variation in demand is also very crucial. An additional factor for operational variability is that excess demand does not deviate just between night and day. There are also significant variations in the time of year and day of the week. A region that has large variations in demand will require a huge load following or peaking power plant capacity because base load power plants can only cover the capacity equal to that needed during times of lowest demand.