Principle of Generating Load in Coal Power Plant


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As we know that Generator converts mechanical energy to electrical energy but when we increase fuel then load generates accordingly. Factors like frequency 50hz and RPM 3000 remain same then what are the other factors helps to increase load. What is the principle behind it? Please elaborate it in brief.

Also refer me some pdf link to get proper knowledge on this power plant knowledge.

The principles of generation for any power plant when it comes to AC power production are the same. Chemical energy is converted to pressure which is converted to torque which is applied to the generator. The generator has to run at a constant speed to produce power at a constant frequency (the frequency of a generator is directly proportional to the speed of the generator rotor). A certain amount of energy is required just to rotate the generator rotor at the proper speed for the desired frequency (called synchronous speed). Once the generator breaker connecting the generator and its prime mover (turbine; engine) to the grid is closed increasing the energy flow-rate into the prime mover will increase the torque produced by the prime mover and applied to the generator, and the generator will convert that torque to amperes. But, the speed of the generator must remain fixed to generate power at the desired frequency.

There have been lots of threads on about this over many years. There is a 'Search' field cleverly hidden at the far right of the Menu bar at the top of every page. (Use the Search 'Help' first for best results!)

There really isn't any difference between a coal-fired thermal power plant and a gas turbine driven power plant and a diesel engine driven power plant--they all convert chemical energy into torque which is applied to the generators which convert the torque into amperes. The devices connected to the grid (motors, lights, TVs, computers and computer monitors) convert the amperes into useful work (if you can watching TV useful work, or watching YouTube videos on the Internet useful work!).

There is a very useful website with a lot of .pdf files about power generation. Though it was produced for nuclear power plants, the electrical generation fundamentals don't change because the prime mover and the source of the energy being converted into torque is different. is the site, and it has LOTS of REALLY good information. Again, the principles of AC power generation don't change because the prime mover changes. Torque is torque, no matter where it comes from--a wind turbine, a gas turbine, a steam turbine, a diesel engine, a gasoline engine, or a flywheel driven by mice running inside a wheel in a cage (that was one of the science experiments I did in primary school--to light a small flashlight bulb; it wasn't very bright, but it did illuminate!).

You might also search some used book websites for references and handbooks. is a very good site. Books like 'Power Generation Handbook' are very good. You don't need the latest and greatest edition--you're just looking for fundamentals. And those don't change. Haven't changed for decades.