A numerical method is proposed to calculate earth-energy of earth-air-pipe heat exchanger during winter heating. The proposed method is based on using numerical computation developed on Scilab a free open source software. Authors showed the comparison between their simple numerical model called Heatground with the well-known Amitrano results. The comparison is given for different parameters as the airflow, the pipe length, the depth of buried pipe, the pipe diameter.

This paper deals with the definition of a new proceduredevoted to the analysis of an autonomous self-excitedinduction generator (IG) comportment. First, for thesteady state, a new single phase equivalent scheme isproposed. Then, this scheme is used to analyze the self-excited starting. Numerical study based on spacephasor theory, as well as experiments, allow to validatethe theorical approaches.

$EVWUDFW 7KH DXWKRUV SUHVHQW D PHWKRG RI GHWHUPLQDWLRQ RI WKH SDUDPHWHUV RI WKH PRGHO GLRGHThe majority of simulations of the working point of the PV module are obtained from the electrical equivalent circuit shown in figure n°3. The knowledge of the electrical parameters is essential to predetermine the behaviour of the panels subjected to various irradiation and temperature. However, the manufacturers only give the external PV characteristics and give less information about these parameters. The authors present a simplified graphical method of determination of these parameters. The manufacturing processes induce disparity in the I-V characteristic. This fact it is possible to find an optimal association of PV modules. However, the expression of the power is implicit and can be only obtained by numerical resolution [1] or iterative. So, it is quite difficult to establish the rules of association of PV modules. The authors show that an approximate analytical expression of the maximum power can be deduced from the equivalent electrical circuit. The expression introduces two remarkable factors such as the open circuit voltage (V OC ) and the short-circuit current (I SC ) and also correction factors in order to take into account the various imperfections of the solar cells. (TXLYDOHQW HOHFWULFDO FLUFXLW RI WKH 39 PRGXOHA PV module is an association made of N S photodiodes connected in series to increase the output voltage and N P identical node to increase the available delivered electrical power.

The aim of this paper is to build an understanding concepts of creation of a stochastic generator of the electrical power delivered by the PV array. Much attention is paid to help fitters to get simply and rapidly simulations of scenarios of the electrical power. The developed generator integrated the effect of the clouds layers by 3 SKY-index which are computed by a statistical approach. The irradiance collected by the PV panels, is deduced from an analytical expression of the theoretical irradiance (without clouds) and the SKY-index. The used databases are provided from the 'European daylight and solar radiation database Satel-light', assembled for the period 1996-2000.

This paper deals with the integration of wind farms in a medium voltage isolated grid. Two main aspects are developed and concerns the regulation of the voltage plan of the grid without and after with the participation of the wind machines in the regulation of the voltage control.