Bizmans.com

The research of the alternative energy resources became a crucial question these days.  A lot of scientific research were taken, not only, in the domain of the production of nuclear energy, but equally in the sector of the limitless sources of energy, such as the production of electricity by the transformation of solar energy.  In the latter case, the conception, the optimization and the realization of pv systems are current problems since they drive surely to a better exploitation of solar inverters.  At the time of the direct connection of pv units to load (batteries,…), important losses of furnished energies can take place, after the Fact that the generator pv no longer works in the optimum conditions.

Currently, the major problem of the production of  electric energy by this technique is, on one hand, the conception and the realization of the pv system, allowing less units to work in pv optimum conditions, and on the other hand, the conception and the realization of the circuits that allow detecting an eventual, suite to the rush variations of the illumination or load, while assuring an optimum functioning of the pv system.

In the latter case, circuits were proposed in the literature.  Their inconvenience is that it let the solar system get going again at the time of the detection of a malfunction.  This upturn could be harmful for the good functioning of the used applications (load, batteries, …).

In this paper, we do the analysis of the conception of pv systems on average power (100 W) that allows optimizing instantly the power furnished by units pv regardless of the meteorological variations and load.  We study, in the environment orcad-pspice, the such a circuit conception that allows the detection of  malfunction and convergence (without upturn) system, following the variations of the illumination or load, while assuring an optimum functioning of the system (circuit of detection of malfunction and of change of direction, ‘CDCS’).  The functioning of this circuit ‘CDCS’ is based on the detection of malfunction and next the change of direction of movement of the point of functioning of the pv generator.

RESULTS AND DISCUSSIONS

For the pv generator to work in the optimum conditions, it must be endowed with an adaptation.  This adaptation realizes itself while looking for in a manner automatic it no maximum power optimizer (PPM) generator.  This can be a convertisseur dc-dc type according to the applications.  The problem that puts itself is to conceive and to realize an order that converges the pv system to optimum points of functioning, regardless meteorological variations and load.

The order MPPT ‘Maximum Power Not at all Tracking’ allows looking for the point of optimum functioning of the pv solar unit in the meteorological conditions and stable load.  This is based on the automatic variation of the cyclic report has, signal that orders the energy, to an adequate value so as to maximize the power to the go out of unit.  In a preceding item, an analysis study was carried out on an analogical order in functioning of the illumination and load.  As we will show it in this paper that the inconvenience of this order
is that she diverges towards the conditions of the closed circuit or open, after the variations of the illumination or load.

The circuit ‘CDCS’ is the circuit that allows the detection of malfunction of unit pv and the change of direction of the movement of the point of functioning of unit.  His role shows itself, when the system diverges after a variation of the illumination or load.