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The construction of a Ganz water Turbo Generator in Budapest in 1886. Water wheels have been used for hundreds of years for industrial power. Their main shortcoming is size, which limits the flow rate and head that can be harnessed. The migration from water wheels to modern turbines took about one hundred years.
The amount of hydroelectric power generated is strongly affected by changes in precipitation and surface runoff. [4] Hydroelectric stations exist in at least 34 US states. The largest concentration of hydroelectric generation in the US is in the Columbia River basin, which in 2012 was the source of 44% of the nation's hydroelectricity. [5]
Due to flexibility allowed by the presence of the power converter, the doubly-fed and full-converter wind generators on the market have different shapes of the capability curve: "triangular", "rectangular", "D-shape" [7] (the latter one resembles the D-curve of a synchronous generator). The rectangular and D-shapes of the curve theoretically ...
Francis type units cover a head range from 40 to 600 m (130 to 2,000 ft), and their connected generator output power varies from just a few kilowatts up to 1000 MW. Large Francis turbines are individually designed for each site to operate with the given water flow and water head at the highest possible efficiency, typically over 90% (to 99% [6]).
A screw turbine at a small hydro power plant in Goryn, Poland. The Archimedean screw is an ancient invention, attributed to Archimedes of Syracuse (287–212 BC.), and commonly used to raise water from a watercourse for irrigation purposes.
These turbines drove a 750 kW generator at 114 rpm. The generators produced 12,000 volts three-phase power at 38 Hz. Two exciter turbine/generators were initially installed to provide 125 V and 250 kW of DC excitation power for the main generators, but DC power has been provided by a static system for more than 50 years.
S-turbines eliminate the need for a bulb housing by placing the generator outside of the water channel. This is accomplished with a jog in the water channel and a shaft connecting the runner and generator. The VLH turbine is an open flow, very low head "kaplan" turbine slanted at an angle to the water flow. It has a large diameter >3.55 m, is ...
A wheel power divided by the initial jet power, is the turbine efficiency, η = 4u(V i − u)/V i 2. It is zero for u = 0 and for u = V i . As the equations indicate, when a real Pelton wheel is working close to maximum efficiency, the fluid flows off the wheel with very little residual velocity. [ 11 ]