A stepwise operating parallel-type hydro power generation system having a fixed flow path, comprising:
- a parallel pipe comprising an inlet pipe to introduce water, an outlet pipe to discharge the water, a first straight pipe and a second straight pipe, the first and second straight pipes connected to and between the inlet pipe and the outlet pipe;
- a first power generation facility and a second power generation facility connected respectively to the first straight pipe and the second straight pipe, each of the first and second power generation facilities comprising a water turbine rotating with the water introduced thereinto and a power generator operating according to a rotation of the water turbine to generate electric power;
- first flow rate regulators and second flow rate regulators configured to adjust a flow rate of the water introduced into and discharged from the first power generation facility and the second power generation facility to control the flow rate of the water for power generation;
- a controller configured to open and close either or both of the first flow rate regulators and the second flow rate regulators at the same time, in accordance with a value sensed by a flow meter disposed on water introduction sides of the first power generation facility and the second power generation facility, and in accordance with power generation quantities of the first power generation facility and the second power generation facility, such that either or both of the first power generation facility and the second power generation facility operate at the same time in accordance with a deviation in the flow rate of the water introduced;
- and
- wherein each power generator comprises a cooler in a direct contact with an outer side of said each power generator to continuously supply and circulate a cooling water to a cooling flow path, thereby cooling said each power generator through a heat exchange with the cooling water, the cooler is a hollow circular plate coupled to an end of said each power generator, the hollow circular plate is formed of a first plate and a second plate, the first plate comprises a ring-shaped supply hole, and the second plate comprises a plurality of holes positioned to correspond to a location of the ring-shaped supply hole on the first plate and the hollow circular plate is configured to supply the cooling water through the ring-shaped supply hole and through the plurality of holes;
- and wherein both ends of the cooling flow path are connected to the plurality of holes between the first and second plates to individually supply the cooling water to the plurality of holes.