Plenary Lecture

Generation of Electrical Energy with Variable Speed in Microhydro and Eolian Power Plant

Professor Sorin Deaconu
Electrotechnical Faculty
“Polytechnica” University of Timisoara
Romania
E-mail: sorin.deaconu@fih.upt.ro
 

Abstract: The mini hydroelectric power plant are built to use the flow of the small rivers .
The main disadvantage of these systems is the reduced capacity to store a high quantity of water which should ensure the long term running of the hydroelectric plants during the droughty periods of time.
In the periods with low flow capacities the steady speed functioning cannot be achieved and a big quality of energy is lost.
This paper presents a mini hydroelectric plant with turbine (T) (without the classical devices of regulate the turbine) which runs with a variable flow capacity of water. The system uses an asynchronous generator which is coupled to the electric network through a static frequency converter (SFC). The frequency converter can be coupled to the network or it can run in autonomous regime, the voltage and the frequency at its output are very strictly regulated.
This way it can be produced electric energy at low and high flow capacities (higher then the rated flow capacity), the gain is obvious.
The figure no.1 presents the principle scheme of the system. In the figure, B represents the breakwater, CPT – the inlet of the feeding pipe, Q – the flow capacity of the water, VBP – by-pass valve, Δh – the drop, VAT – turbine access valve.
The paper proposes a computer simulation and experimental results of the system presented.