A Short Introduction To Steam Powered Electric Generators
Steam powered electric generators are driven by a turbine and typically for 50 to 60 Hz. They are classified as a synchronous generator which is a simple machine compared to others and consists of two basic parts, a stator and a rotator. The stator always remains still and features a cylinder shaped frame. Inside there is a cylindrical iron core which is comprised of insulated laminations and mounted onto a support system. The iron core also has axial slots that are spaced out evenly. This type of system has almost completely replaced the old fashioned wood burning steam engines which used pistons.
Steam powered electric generators use a rotary motion and they are very well suited towards use in an electric generator. As a matter of fact, over 80 percent of the world’s electricity is derived from these machines. They are essentially heat engines that receive their efficiency and superiority due to their multi-stage expansion of steam. These machines are produced in a wide variety of sizes from small 1hp units to massive 2,000,000 hp turbines. There are several different classifications such as condensing, noncondensing, reheat, extraction, induction, and casing or shaft arrangements. Each of the different types is best suited towards a certain type of application.
One type that deserves special attention are the once through steam generators, often referred to as OTSGs for short, which make use of a rare Babcock and Wilcox reactor design. The main feedwater is entered through the machine from a header into an annular downcomer region. As this process is taking place, the cold water draws steam from the tube which quickly heats the feedwater to a saturation temperature. Typically used in nuclear power plants, these steam powered electric generators transfer the heat from the reactor cooling system to the opposite end of the tubing which contains the feedwater. When the feedwater passes through the tubing it gets hotter and turns into steam.
Pure steam generators on the other hand use natural circulation evaporator technology to produces thousands of pounds of steam per hour. By using this method you keep the risk of corrosion to a minimum and it is a very reliable method of producing electricity with little maintenance required. Each system typically includes the following components: temperature and pressure control, PLC and operator interface terminal, level control system, and a choice of several different types of control platforms. There are many other additional services that may be purchased such as WFI production, feedwater conductivity monitoring, pure steam sampling and more.
As you can see, there are several different types of pure steam generators out there and without them we would have a very difficult time producing energy. These are currently the preferred method for use in most power plants as they feature very little maintenance and problems are incredibly rare.
