Kaplan turbine

Kaplan turbines are primarily used in the low head range with large volumes of water. The adjustability of the guide wheel and runner blades allows optimal use of varying water flow. The drive to the generator is preferably via a direct connection or occasionally via belts or gear transmission. Kaplan turbine is widely used in hydro power stations with the head of 2-30 meters. The turbine is made up of several propellers or manually-adjusted blades. Their runner blades/wicket gates double-regulating system provides enhanced performance over a large range of heads and loads. Kaplan turbine is most appropriate for operation with a low head and a large amount of discharge. Owing to adjustable runner blades it offers the significant advantage to give high efficiency even in the range of partial load, and there is little drop in efficiency due to head variation or load. As a result of recent advances, the range of Kaplan turbine applications has been greatly improved, which favours numerous undeveloped hydro sources previously discarded for economic or environmental reasons. As having adjustable runner blades, the construction of Kaplan turbine becomes naturally a bit complicated. The runner blade operating mechanism consists of a pressure oil head, a runner servomotor, and the blade operating rod inside the shaft etc.