Abstract
Obtaining energy from renewable resources is a worldwide trend in the age of increasing energy demand. Hydropower has some potential in this field, especially for low-power locations. However, construction of such facilities requires high expenses, which is why some attempts at lowering the costs have been made, i.e., by proposing alternative solutions to the classic ones. This paper proposes a selection of options for small hydropower plants (SHP) that lower the investment costs while keeping up profitable operations. The proposed solutions concern simplifying the turbine’s and generator’s integration by installing them in dedicated prefabricated concrete modules. A rare but simple and cheap semi-Kaplan type of turbine with a non-classical spiral inflow is proposed. The turbine operates a permanent magnet (PM)-excited generator, converting the energy at a variable rotational speed. Thanks to this approach, it is possible to simplify the regulation system and eliminate expensive mechanical transmission. However, on the power grid side, a power electronic converter (PEC) must be coupled with the generator. The advantage of this solution compared to the classical ones is that the reliability of power electronics is much higher than that of mechanical systems. This paper presents modeling research on semi-Kaplan turbines’ series development, and a dedicated PM generator is presented as an example of a complete hydro unit with 50 kW power.
Highlights
The hydropower potential of medium- and high-water damming is already used in most countries
This paper presented a semi-Kaplan type of turbine, designed for use in small hydropower plants characterized by low heads, i.e., with low hydro potential
This paper presented an alternative design solution for how to integrate a hydraulic turbine with an electric generator, aimed at the modular construction of a hydro unit characterized by relatively high efficiency and reliability
Summary
The hydropower potential of medium- and high-water damming is already used in most countries. Placing the oil-lubricated gear inside the casing risks oil leakage and river pollution Such a design of low-head low-power hydro units is not effective due to the limitation of the flow cross-section area and significant water-flow turbulences in the hydraulic channels of the machine. Significant advantages of the full integration of the turbine inside the electric generator’s rotor are the size adjustment of the hydro unit compared to the pipe segment and the lack of a drive shaft and gears, meaning a turbine set can be placed directly in the pipe Another significant advantage of such a design is the electric-generator cooling by the water flowing inside its housing, which efficiently prevents long-term generator overload
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have