HK1166181B - High-concentration single-reflection photovoltaic generating module and photovoltaic generator - Google Patents

Description

High-concentration single-reflection photoelectric generation module and photovoltaic generator

The present invention generally relates to a high concentration photovoltaic generation module.

More particularly, the present invention relates to a solar concentrator, a photoelectric receiver of the solar concentrator and a high-concentration photoelectric generation module obtained by using the concentrator and receiver device.

Known concentrated photovoltaic generating systems generally comprise a series of cells (so-called photovoltaic cells) which convert the incoming sunlight into electrical energy, and at least one concentrator which allows the sunlight to be concentrated onto said cells.

The concentrator device may be of the reflective surface type (mirror) or of the lens type.

Based on the geometry created by the reflecting surface, it is possible to vary the acquired concentration factor.

A greater solar concentration factor can be obtained using a concentrator with a curved reflective surface, such as a parabolic concentrator which presents a section formed by a curved portion of a parabola in the direction of incidence of the solar beam.

However, even in this case, the solar concentration factor is low.

Other known types of concentrators with reflecting surfaces use parabolas, which are able to concentrate the solar beam over a small area, substantially corresponding to the focus of the parabola, where one or more matrices containing a plurality of photovoltaic cells are arranged.

These systems provide a high concentration factor, but such devices can perform well only when the solar beam strikes the cell exhibiting a high degree of uniformity, a feature that can be obtained by using an additional concentrator (e.g. parabolic geometry) in front of the photovoltaic cell.

In any case, a single reflective concentrator with multiple reflective surfaces is problematic for building a heat removal system, since a passive heat removal system must be distributed over the surface across which the sunlight traverses before reaching the mirror.

For this reason, single reflective concentrators typically use active heat dissipation systems to avoid overheating of the photovoltaic cells.

A lens-type concentrator typically comprises a series of optical lens units, each adapted to directly receive sunlight and concentrate it onto an associated photovoltaic cell.

The concentration factor that can be obtained with such a system is high and the heat generated by the concentration of the sunlight can be dissipated in a passive manner, but it is difficult and expensive to construct the lens with a durable material such as glass, and lenses made of acrylate (metacrylate) whose durability has been discussed so far are often used, which results in very rapid deterioration of the material used in any case.

It is therefore an object of the present invention to overcome the above drawbacks and in particular to create a high concentration photovoltaic generation module that allows to realize a more efficient optical system with respect to the prior art, while using an equal size and number of photovoltaic cells.

A further object of the present invention is to provide a high concentration photovoltaic generation module which allows the heat generated inside the module to be better dissipated than in the prior art.

Another object of the present invention is to provide a generator and a photovoltaic receiving device suitable for use in a high concentration module for photovoltaic power generation.

A further object of the present invention is to consolidate (concrete) high concentration photovoltaic generating modules which have a significant competitive advantage in terms of simplicity and rapidity of installation and a great reduction in operating costs with respect to the conventional construction solutions.

In an advantageous manner, with a matrix of 64 elements (110x110mm each), efficiencies of over 21% of the photovoltaic generation module are achieved for an overall size of 900x900mm (with a thickness or height of about 150 mm).

The minimum efficiency achieved by the optical system is about 70% and by using a structure comprising 20 modules (total size 4.600x3.900mm) a power of 3KW is generated.

Additional features and advantages of the high-concentration photovoltaic generation module according to the present invention will become clearer from the following description, which relates to an exemplary and preferred but not limiting embodiment, and to the attached drawings, which are also exemplary and preferred but not limiting, wherein:

figure 1 shows a perspective view of a first embodiment of a high concentration photovoltaic generation module according to the present invention;

figure 2 shows a perspective view of a further embodiment of a high concentration photovoltaic generation module according to the present invention;

figure 3 shows a schematic view of a condenser used in a high-concentration photovoltaic generation module according to the present invention and illustrating its own working principle and the corresponding light beam obtained by a "ray tracing" technology simulator;

figure 4 shows an enlarged detail of figure 3 according to the invention;

figure 5 shows a schematic view of the concentration obtained by the photovoltaic generation module of figure 1 according to the present invention;

figure 6 shows a schematic view of the concentration obtained by the photovoltaic generation module of figure 2 according to the present invention;

fig. 7 is a schematic partial cross-sectional view of the high-concentration photovoltaic generation module of fig. 1, in which the heat flow is highlighted, according to the invention;

fig. 8 is a schematic partial cross-sectional view of the interior of the high-concentration photovoltaic generation module of fig. 2, in which the outward heat flow is indicated, according to the present invention;

figure 9 shows a perspective view of a photoreceiver used in a high-concentration photovoltaic generation module according to the invention;

fig. 10 is a schematic partial cross-sectional view of a photovoltaic cell of a high concentration module according to the invention mounted on the receiver shown in fig. 9;

figure 11 shows a perspective view of the first detail of figure 9 according to the invention;

figure 12 shows a perspective view of a second detail of figure 9 according to the invention;

figures 13 and 14 show two schematic partial cross-sectional views of the high-concentration photovoltaic generation module of figure 1 according to the present invention;

figure 15 shows a front view of the high-concentration photovoltaic generation module of figure 1 according to the present invention;

figure 16 shows a rear view of the high-concentration photovoltaic generation module of figure 1 according to the present invention;

figure 17 shows a top view of the high concentration photovoltaic generation module of figure 1 according to the present invention;

FIG. 18 is a schematic view of a photovoltaic receiver mounted on a heat sink within the photovoltaic generation module of FIG. 1 according to the present invention;

figure 19 shows a front view of the high-concentration photovoltaic generation module of figure 2, according to the present invention;

figure 20 shows a rear view of the high-concentration photovoltaic generation module of figure 2, according to the present invention;

figure 21 is a schematic view of a photovoltaic receiver mounted on a heat sink within the photovoltaic generation module of figure 2 according to the present invention;

figure 22 shows a wiring diagram between the receivers of the high-concentration photovoltaic generation module according to the invention;

figure 23 shows a wiring diagram of the photovoltaic cells in the high concentration photovoltaic generation module according to the invention;

figure 24 shows a schematic implementation of a photovoltaic generator starting from a high concentration photovoltaic generation module according to the present invention;

figure 25 shows a wiring diagram of a high concentration photovoltaic generation module according to the invention placed inside a 3KW photovoltaic generator;

figure 26 shows a circuit diagram of an electrical module converter;

figure 27 shows a wiring diagram of the photovoltaic generation module together with the electrical converter of the on-board related figure 26 in a 3KW photovoltaic generator;

fig. 28 shows a block diagram of a photovoltaic generation system implemented by means of a high concentration photovoltaic generation module according to the invention and integrated with a home automatic energy management system in an existing commercial/residential cycle.

With reference to said figures, a high concentration photovoltaic generating module according to the present invention is generally indicated with 11 and can be carried out with two different embodiments, respectively illustrated in fig. 1 and 2, which provide an elongated heat dissipating element 10 placed outside the module 11 and an elongated heat dissipating element 12 placed inside the module 11, respectively.

In either the embodiment of fig. 1 or the embodiment of fig. 2, the photovoltaic module 11 comprises:

a plurality of solar radiation concentrating devices comprising parabolic reflectors 13 each mounted on the internal and lower planes of the module 11;

a transparent front surface 14 through which solar radiation is transmitted;

a lower or bottom base 15 for supporting the reflector 13;

a plurality of photovoltaic receivers 16 mounted inside the module 11 on the elongated radiating elements 10, 12; and

suitable brackets 17 for fixing the modules 11 to each other and/or to fix the modules 11 to the complete photovoltaic generator system.

With particular reference to fig. 3-6, each solar radiation concentrator comprises a parabolic reflector 13 which concentrates the solar radiation RS on the inlet BI of the second homogenizing optic OS.

In practice, the incident light of the solar radiation RS crosses the transparent protective surface 14 of the module 11 and is reflected on the parabolic reflector 13 to converge on the focus of the parabolic reflector at the entrance BI of the second optical component OS as the incoming light stream RST.

The second optical part OS is in fact constituted by a truncated pyramid, the side walls of which reflect, thanks to the phenomenon of total reflection, the rays of the sun entering the entrance BI.

Furthermore, the side wall has a specifically designed inclination so that the truncated pyramid acts as a homogenizer of the incoming light flow RST.

In this way, the underlying photovoltaic cells CS, located at the inner side 18 of each elongated radiating element 10,12, are illuminated by the homogenized luminous flow, without solar incident dispersion peaks on the above-mentioned cells CS.

Another purpose of the second optical component OS is to increase the acceptance angle of the optical system, i.e. the maximum misalignment angle allowable by the concentrator with respect to the direction of the sunlight.

Using the second optical component OS, the maximum allowable misalignment angle of the concentrator is about 1-2 °.

The incoming solar radiation RS is therefore totally concentrated, the geometric construction concentration factor, being the ratio between the area of the entry surface of the parabolic reflector 13 projected onto the transparent surface 14 and the area of the photovoltaic cell CS, being equal to 1.260 (geometric concentration is in fact equal to (110x110mm)/(3.1x3.1 mm)).

Each photo-reflector 13 is manufactured by at least one of the following techniques:

1) mirror polishing on the aluminum sheet stretching and sinking surface;

2) injection molded plastic (polycarbonate or equivalent material) obtained from a mirror polishing module and deposited metallic aluminum under vacuum by evaporation or sputtering;

3) mirror glass and deposition of metallic aluminum in vacuum by evaporation or sputtering.

The truncated pyramid comprising the second optical component OS is made of glass or quartz, which is only a transparent material (high in light transmittance in the radiation band of interest (comprised between 300 and 2000 nm)) capable of reliable operation for many years, despite its ease of crossing by a high density of solar radiation RST.

The solar or photovoltaic cell CS used is of the multijunction type, made of III-V material (germanium, gallium, arsenic, indium), and it is preferably of the triple junction type, characterized by a conversion efficiency of about 35%, equal to 1.000.000W/m, when concentrating 1.000 suns (suns)²(equal to 100W/cm)²)。

The efficiency of the optical system as a whole is affected by losses across the protective glass 14, by reflection losses on the paraboloid 13, by losses across the second optical component OS and by darkening losses (which arise from the shadow created by the elongated radiating strips 10,12 on each of which a solar or photovoltaic cell CS is mounted), generally between 67% and 80%, and may exceed 88% when a silver reflector is used in particular.

The following table summarizes the minimum and typical efficiency values of the optical system, respectively without any treatment of the mentioned surfaces (transparent surface or protective glass, parabolic reflector, second optical component), with a reflection-reducing treatment and/or a special covering process.

The maximum solar radiation incident on the photovoltaic module 11 is equal to 1000W/m²And the power produced by projection as a parabolic reflector 13 on the transparent surface 14 is equal to (1.000x0,11x0,11) W — 12, 10W.

The power incident on the cell CS is between 8,11W (12,10x0,67) and 9,92W (12,10x0,82) in terms of the efficiency of the optical part, and the part of the power incident on the cell CS that is converted into heat and thus necessarily dissipated is between 2,84W (8,11x0,35) and 3,47W (9,92x0,35) in terms of the electrical efficiency of the cell CS.

In the embodiment shown in fig. 1 and 5 (i.e. with the elongated heat-dissipating elements 10 placed outside the module 11), the heat to be dissipated is spread outwards across the elongated elements 10, which are preferably made of aluminum; thanks to this solution, the dimensions of each elongated heat dissipating element are minimized, which is capable of keeping the operating temperature value of the battery CS below 80 ℃, since the elongated heat dissipating element is approximately 6x55 mm.

The optimal operation of each elongated radiating element 10 results from the fact that a large portion of the surface of the aforementioned elongated radiating element 10 (the portion marked a in fig. 5) is directly facing the outside of the module 11; furthermore, the small size of each aluminum elongated heat dissipating element 10 allows keeping the overall cost to a minimum.

Even the embodiment shown in fig. 6 (with elongated heat dissipating elements 12 placed inside the module 11) works well thermally, but this embodiment requires a greater amount of aluminum due to the need for a mesh structure made in the module 11, consisting of an inner portion 19 of each elongated heat dissipating element 12 and a mesh of aluminum flow tubes 20, connected with the elongated elements 12 with low thermal resistance, on which the CS batteries are mounted.

In this way, it is in fact possible to increase the aluminium surface present inside the module 11, in order to exchange heat with the air in the same module 11 and to transfer heat to the lower base 15 with as low a thermal resistance as possible, which is preferably made of aluminium and is in thermal communication with the interior 19 of each elongated radiating element 12, so as to allow the transfer of heat to the air present outside the module 11 through the rear surface 21 of the base 15 facing the outside, which rear surface 21 allows the heat exchange.

In particular, in fig. 7 the heat flow, indicated with arrows C, is formed inside the photovoltaic module 11 with the elongated heat dissipating elements 10 placed outside the module 11 of fig. 1, while in fig. 8 the heat flow, indicated with arrows B, is formed inside the photovoltaic module 11 with the elongated heat dissipating elements 12 placed inside the module 11 of fig. 2.

Both embodiments, with elongated heat dissipation elements 12 placed inside and outside the module 11 respectively, allow to effectively dissipate the heat generated by the solar cells CS and make it possible to construct a single reflective concentrator photovoltaic module 11 with negligible dimming losses due to the support structure of the cells CS.

Based on the strips 19 and/or the aluminium flow tubes 20, a passive heat dissipation solution is made possible without the use of forced circulation of cooling liquid and/or other complicated and expensive solutions.

The advantages of the single reflection embodiment are also: high optical efficiency can be achieved due to losses attenuated by only a small percentage (5%) by the shadow phenomenon caused by the presence of the supporting and heat dissipating structures of the cells CS.

The result of this is that the light collection of the module is very compact, easy to produce and inexpensive.

The embodiment with elongated heat dissipating elements 12 placed inside the module 11, although requiring a greater amount of aluminium than the embodiment with elongated heat dissipating elements 10 placed outside the module 11, advantageously presents a single smooth and transparent upper surface 14 (in fact a single panel made of glass) without the presence of projections.

With particular reference to fig. 9-12, each photovoltaic receiver 16 of the module 11 (for greater clarity, the second optical component OS is not shown in fig. 9), is made up of:

alumina plate 22, which presents high thermal conductivity and high electrical insulation;

-a solar or photovoltaic cell CS;

-a bypass diode 23;

two shaped elements 24, 25 made of brass or tin-plated copper, on which copper wires are welded, for interconnecting and extracting the photocurrent from the various receivers 11 of the photovoltaic module 11.

The shaped element 25 placed above the bypass diode 23 also has the following purpose: in the event of misalignment of the module by several degrees with respect to the sun, the silicon diode 23 (placed inside the black plastic envelope) is protected from the solar radiation RST incident and concentrated by the parabolic reflector 13, in which case the concentrated solar beam RST can in fact cause damage to the epoxy surface of the diode 23, due to overheating caused by the concentrated solar beam RST.

The embodiment shown in fig. 9 also allows two functions to be achieved with a simple metal element 25: electrically connecting; and protection from the concentrated solar beam RST is achieved.

On the alumina plate 22 there are silver screen printed conductive tracks 27 made by thick film technology on its own surface, forming the electrical connections between the solar cell CS, the diode 23 and the shaped elements 24, 25.

Furthermore, the solar cell CS is mounted on the plate 22 by soldering the bottom face of the cell CS (one of the two electrical contacts constituting the cell itself) to the plate 22 with tin or a polymeric solder 26 conducting heat and electricity, and connecting the other electrode of the photovoltaic or solar cell CS with a conductive track 27 of the plate 22 by means of a bonding wire 28 (shown in detail in fig. 10).

By way of example and preferably, but not by way of limitation, each structured module 11 of the embodiment of the invention comprises 64 photoreceivers 16 connected in series with each other, as shown in detail in figures 13-21.

In particular, in the modular structure 11 with the external elongated heat dissipating elements 10 (fig. 13-18) there are transparent surfaces or glasses 14, located at the front and rear, and at the bottom surface 15, a parabolic reflector 13 is attached (preferably by gluing) inside the module 11 at the rear transparent surface 14.

Fig. 22 shows a wiring harness between two photoelectric receivers 16 adjacent to each other.

The electrical connections are made of hard bare wires 30 of copper (i.e. without insulation) or of conductive strips of tin-plated (often made of copper), which are soldered to the ends 31 of the profiled elements 24, 25 of the respective photovoltaic receiver 16 and are hung a few millimetres (5-10mm) from the alumina base plate 22 and the aluminium elongated elements 10,12, so as to form an electrical insulation by air.

This solution allows to implement low-cost connections between the receivers 16, while guaranteeing maximum durability and minimum resistance, since the bare wires 30 (without plastic insulating wrapping) are not exposed to damages that may be caused by misalignment conditions of the modules.

In fact, even if the structured module 11 is misaligned with respect to the sun, it may affect the copper wires 30 (several tens of W/cm)²Intensity) of the light beam RST does not cause any problems; conversely, if plastic insulation is used, the converging light beam RST will damage the insulation.

The use of teflon insulation or other special materials may be an alternative to plastic insulation, although in this case the cost would be much higher than the copper bare wire solution.

Therefore, all the photovoltaic receivers 16 of the structured module 11 are connected in series as in the connection diagram shown in fig. 23, and 64 photovoltaic cells CS (preferably distributed according to a matrix of 8 × 8) are connected in series.

Furthermore, as already described, each solar cell CS is connected in parallel with a bypass diode 23, which prevents overheating and consequent damage to the single solar cell CS, in the case where the single cell CS itself is in a shadow condition, while the other cells CS are in a full radiation condition.

The performance of the series-connected modules 11 is optimal because the currents flowing through the batteries CS are the same, while the voltages of the batteries CS, added to each other, provide a high voltage output V facilitating the conversion necessary to bring it to the common power supply.

For example, using solar cells of the III-V type, each cell provides an output voltage of about 2,3 volts (under maximum power conditions, the voltage V output from the module 11 is 147 volts (2,3x64), while the output current of the module 11 is equal to the current produced by each cell CS, which is equal to about 1 ampere under maximum power conditions.

The modular structured module 11 provides the output of two terminal cables C1, C2 from the frame of the module 11 through two simple cable guide holes.

The photovoltaic generator 34 according to the invention is composed of several structured modules 11, as shown in fig. 24, connected in series and in parallel to each other and to the solar tracker 33.

The various modules 11 are connected to provide a Direct Current (DC) bus with two terminals C1, C2, which are connected to the input of a DC/AC converter required for the power supply function C1, C2.

For example, a 3kW photovoltaic generator 34 may be constructed from a matrix (5x4) of 20 concentrating photovoltaic modules 11 (each module manufactured according to the embodiment shown in fig. 1 or 2) mounted on an ionic monowing identified at 32 in fig. 24.

Similarly, a 4,5kW photovoltaic generator 34 may be constructed from a matrix (6x5) of 30 photovoltaic modules 11, each 150W.

The structured modules 11 are connected in series and in parallel as shown in figure 25, which refers to the case of a photovoltaic generator of 3kW (constituted by 20 modules 11 of 150W each, outputting a voltage V of about 300 volts at the terminals C1, C2).

Fig. 26 shows a circuit diagram of a three-phase "interleaved" type modular DC/DC converter, which is used in an illustrative and preferred way, but without limiting the embodiment of the photovoltaic module 11, and which is applied to the module 11 inside a small-sized sealed box, which is mounted outside the module 11 itself and connected to the battery CS. In this arrangement, the connection of the modules 11 does not occur as in the arrangement shown in fig. 25.

Terminals C1 and C2 of fig. 23 (i.e. the output terminals of the single module 11) are connected respectively to the inputs I1, I2 of a converter governed by a controller M which in turn generates control signals for the three MOSFETs Q1, Q2 and Q3 and adjusts the power absorbed by the photovoltaic module 11 which attempts to maximize the intensity at each operating instant (by means of a so-called MPPT (maximum power point tracking) function).

This operation is one of "interleaved parallel" and is constituted by three boost-type (boost) switching converters, such as those comprising components (Q1, L1, D1, C1), (Q2, L2, D2, C2) and (Q3, L3D3, C3), all connected in parallel to each other and controlled to be temporally alternated and equally distributed on the time-phase axis, this technique allowing, among other things, to minimize the "ripple" of the input current switching frequency of the terminal I1, and the operation of the photovoltaic cell CS is optimal since the peak value of the intensity of the current itself is reduced.

The controller M comprises a microcontroller and suitable signal conditioning circuits, so that the aforesaid controller M derives the supply voltage from the line VIN for its own operation and simultaneously measures the input voltage, which is the series voltage of the solar cells CS constituting the module 11.

Line IIN is connected to a current sensor SC that measures the current at the converter input, while G1, G2, and G3 are control signals for the gates of MOSFETs Q1, Q2, and Q3, respectively, 120 ° out of phase with each other, and line VOUT allows the output voltage V1 of module 11 to be measured.

In fact, once the voltage of the solar cell CS exceeds a minimum or starting value, for example greater than half the nominal value (such as 75 volts in the case of a nominal voltage of 150 volts for the module 11), the converter starts to operate, adjusting the output voltage V1 to a predetermined value of 400 volts (always greater than the maximum voltage value of the solar cell CS).

The converter measures the input current on each time line IIN and the input voltage on line IIN and calculates the product between this voltage and current as the input power, while the controller M generates a control algorithm that strictly maintains a set voltage of output voltage V1 to 400 volts, continuously varying the "duty cycle" control of the gates of G1, G2 and G3 to maximize the input power at each instant.

The converter therefore operates at the output as a generator, which provides the output at each instant (400 volts, the maximum current that can be used by the electrical loads connected downstream of the converter).

As shown in fig. 27, the output of the converter is connected in parallel with the outputs of the other converters of the other modules, and in order to inject the generated energy into the power supply, the output of the converter may also be connected with the input of a DC/AC converter (inverter) adapted to be connected with a common power supply.

The advantages of using the converter of fig. 26 are basically: making the photovoltaic modules 11 forming each photovoltaic generator 34 independent, the photovoltaic generator being made up of several modules 11; in fact, each converter and each module is able to provide the maximum amount of power available from each single module 11 at any moment.

In the case where the high concentration modules 11 are each equipped with a converter of fig. 26, the connections between the modules 11 forming a photovoltaic generator 34 (for example 3kW) are as shown in fig. 27 (i.e. all modules are connected in parallel with each other).

Finally, the photovoltaic generator 34 can be associated, through a circuit breaker and with the control system of the motor of the solar tracker 33, with an inverter 35, the inverter 35 incorporating a booster (boost) when the generator 34 is integrated in an energy management and/or household automation system (as shown in fig. 28).

In this case, the inverter 35 provides 3,3kW of peak power, a 3kW operating range, and a series of backup batteries 36 for emergency operation without power from the common power source 39.

The inverter 35 is connected wirelessly (FH-DSSS type radio wave communication) with a power supply home power source 41 calculator 37, a power consumption calculator 38, and any intelligent switches 40 (for operation on the island).

A control unit for home control use is also provided, suitable for the all-round management of optoelectronic systems and security systems, which is in radio communication (two-way radio communication) within the 2,400-and 2,486GHz band via FH-DSSS and/or GSM, with a series of sensors and/or actuators for home automation, security, theft protection, self-powering with non-rechargeable batteries (self-powered), such as passive infrared detectors, perimeter detectors, smoke detectors with emergency lighting, gas detectors, overflow detectors, portable remote controls, wireless keyboards, intelligent radio-controlled alarms for the outside, sockets 42 (for external or internal use) for the management of the related loads 43.

A mobile terminal 45 with a "touch screen" interface is also provided, which functions as follows: telephone, remote assistance, electrical, lighting, security and home automation commands and controls, and also has the following functions: monitoring and configuration of photovoltaic systems and energy, lighting (lighting on/off, etc.), and other automation (such as garage door openers, anti-theft devices, etc.).

All the devices are provided with 2,4GHz FH-DSSS radio and are able to interact with each other in real time, obtaining automated functions (in particular management of current-mode energy) that go beyond the usual functions of safety management and moderate automation.

Specifically, the "booster" inverter 35, smart jack 42 and smart switch 40 operate as follows:

the "booster" inverter 35 keeps the battery 36 charged, typically by using energy from the photovoltaic generator 34 or from the optical utility 39, while the intelligent switch 40 incorporates a suitable potentiometer to exchange net electrical power with the utility 39.

In all electrical systems connected to the power supply, the electrical system is automatically disconnected from the common power supply 39 in case the power drawn from the common power supply 39 exceeds a maximum supply limit, which is defined by the power supplier and regulated by an automatic breakdown device (not shown in the figures).

The intelligent switch 40 therefore signals this information to the "booster" inverter 35 immediately through the built-in FH-DSSS radio communicator by detecting that the power absorption is greater than the existing provider maximum limit.

The latter, by detecting such a condition, activates itself to draw energy from the battery 36 to supply the lack of power to the household power supply 41.

Obviously, in the presence of solar energy, the energy that may be needed is extracted directly from the sun, and in this case, the operation is as follows: one of the customary photovoltaic systems is connected to a common power supply, wherein the energy balance at each moment is determined on the basis of the fact that the total power of the user is equal to the sum of the common power supply and the photovoltaic system.

For example, when the sky is dark, the amount of power generated by the photovoltaic system is significantly reduced, and the "booster" inverter 35 is able to constantly run the electrical loads of the house that exceed the power capacity of the common power supply 39, thanks to the energy stored in the battery pack 36.

This mechanism provides benefits to both the user (who uses an excessive load relative to the power supplied by the common power source 39, which eliminates the need for such a user to expend the costs incurred by making more power contracts) and the provider of the common power source 39 (which appears to reduce the energy flow in its power source).

In fact, the energy storage system varying the output through the "booster" inverter 35 allows to stabilize the available energy of the photovoltaic system for direct use locally, not only immediately but also by time indirection (a "programmed through time").

Another possible function concerns the smart socket 42, which can be coordinated with a "booster" inverter 35 and a load 43, which may be constituted, for example, by a household appliance such as a washing machine.

The user only prepares for the operation of the household appliance (for example he loads the washing machine with white items to be washed) and, thereafter, the smart socket 42 connected to the household appliance adjusts its operation according to the electricity available from the renewable source constituted by the optoelectronic system.

In this way, the washing machine in the example is turned on by the smart switch 42 only during the day (energy from the sun), again reducing the energy flow through the utility grid.

The benefits of this electrical system are evident: the photovoltaic energy is used directly in the most efficient way, close to the generator that produces it, without burdening the public electricity network 39, and therefore the advantages deriving from it are the greatest.

The obvious advantages for the user are: in fact, even if the device is under high power consumption, because it is managed by the smart socket 42, the available power in the household power supply 41 (because it is at any time from the sun's function) is not reduced; thus, the user can draw energy for other purposes without worrying about the automatic breakdown due to the surplus of available power demanded from the supplier.

A third possible innovative function, thanks to the "booster" inverter 35 and the intelligent switch 40, relates to the management of the public power grid 39 in the event of a power outage.

In fact, upon detecting the absence of energy from the public power supply 39, the intelligent switch 40, which safely disconnects the household power supply 41 from the public network 39 (with redundant electromechanical devices) and which is simultaneously equipped with a small backup battery for its own operation even in the absence of the supply of energy from the public power supply 39, communicates by radio to the "booster" inverter 35 to activate, for example, the main generator (and no longer the asynchronous generator with the public power supply 39) in order to supply energy to the local household power supply 41 according to the so-called "island" operation.

Even in the case of smart sockets 42 operating with the system, since, according to the energy available from the battery 36 and/or the photovoltaic generator 34 and according to the emergency strategy defined by the user, only part of the smart sockets 42 will be activated to ensure the powering of the "island" system without overloading the "booster" 35, and in the negative, according to predetermined requirements, to ensure the best compromise between the "island" operating time (determined by the length of the outage and the energy stored in the battery 36) and the amount of power required by the electrical loads 43.

From the description, the characteristics of the high-concentration photovoltaic generation module (subject of the invention) and the resulting advantages are clear.

Finally, it is clear that various changes may be made to the photovoltaic module in question, without for this reason loosing the original novelty principles inherent to the inventive idea, since it is clear that in the actually performed invention the materials, shapes and dimensions specified may be any according to requirements and that the same items may be replaced by others that are technically equivalent.

Claims (16)

1. A high-concentration single-reflection photovoltaic generating module (11), comprising:

-a plurality of solar radiation concentrating devices comprising associated parabolic reflectors (13) mounted on a base support (15), said base support (15) being placed inside the module (11);

-at least one transparent front surface (14), through which front surface (14) solar radiation is transmitted;

-a plurality of photo-receivers (16) mounted within the module (11) and connected in series with each other;

wherein the photoreceivers (16) are fixed on elongated elements (12) made of electrically conductive material and capable of dissipating heat, at least a portion of each elongated element (12) being placed inside the module (11),

characterized in that said module (11) has a reticular structure comprising elongated elements (12) parallel to each other and a plurality of flow tubes (20) made of conductive material, each flow tube (20) being perpendicular to said elongated elements (12) and having one side thereof connected with a low thermal resistance to the interior (19) of each elongated element (12) and the other side thereof connected with a low thermal resistance to said base support (15) so as to facilitate the heat exchange with the air in said module (11) and to transfer heat to said base support (15), said base support thereby being in thermal communication with the interior (19) of said each elongated element (12).

2. Module (11) as claimed in claim 1, characterized in that each parabolic reflector (13) concentrates the solar radiation transmitted through the transparent front surface (14) at the entrance (BI) of the mixing optical system as an input light stream.

3. Module (11) according to claim 2, characterized in that the mixing optical system is made in the shape of a truncated pyramid, the side walls of which are shaped to reflect and mix the input light flow.

4. Module (11) as claimed in claim 1, characterized in that said parabolic reflector (13) is made of stamped and mirror-polished sheet metal, or of a plastic support obtained by mirror polishing and metallising molding, or of printed and metallised glass.

5. Module (11) as claimed in claim 1, characterized in that each opto-electronic receiver (16) comprises:

a substrate (22) on which conductive traces are present;

at least one of the photovoltaic cells is provided with a plurality of photovoltaic cells,

at least one bypass diode (23) connected in parallel with the at least one photovoltaic cell,

at least two profiled elements (24, 25) made of a conductive material, at least one wire (30) being connected to the profiled elements for electrically connecting at least two photo receivers (16) in series such that at least two respective photo cells of the at least two photo receivers (16) are connected in series.

6. Module (11) according to claim 5, characterised in that the bypass diode (23) is placed under at least one (25) of the profiled elements (24, 25) to protect it from the incoming solar radiation.

7. Module (11) according to claim 6, characterized in that said at least one photovoltaic cell is mounted on said substrate (22) and is in electrical and thermal communication with said substrate.

8. Module (11) according to claim 1, characterized in that at least one transparent rear surface (14) is located at the base support (15) and the parabolic reflector (13) is fixed to the transparent rear surface (14) within the module (11).

9. Module (11) according to claim 5, characterised in that said at least one wire (30) is free of insulation and is welded at the end (31) of the profiled element (24, 25) of each photovoltaic receiver (16) and hangs at a fixed distance from the base plate (22).

10. Module (11) according to claim 1, characterized in that the module (11) is connected to a three-phase DC/DC converter, controlled by a controller (M) which regulates the power extracted by the module (11) in order to maximize the power intensity and the maximum current of each module (11) available and used by the electrical loads connected downstream of the converter at any given operating time.

11. Module (11) according to claim 10, characterized in that the three-phase DC/DC converter is an "interleaved parallel type" converter.

12. Module (11) according to claim 10, characterized in that the output of the converter is electrically connected in parallel with the output of the other converters of the other modules (11).

13. Module (11) according to claim 10, characterized in that the output of the converter is electrically connected to the input of an inverter, which is connected to a common power source (39).

14. Photovoltaic generator (34) comprising a plurality of high concentration single reflection photovoltaic generating modules (11) according to claim 1, characterized in that said modules (11) are electrically connected in series and/or in parallel to each other and to at least one solar tracker (33).

15. Photovoltaic generator (34) as claimed in claim 14, characterized in that said modules (11) are mechanically connected to a single support (32) and in that said modules (11) are electrically connected to each other, providing an output DC bus having terminals (C1, C2) connected to the input of a DC/AC converter capable of injecting the electricity supplied by the generator into a common power source (39).

16. Photovoltaic generator (34) according to claim 14, characterized in that it is connected to at least one inverter (35) through a circuit breaker and a control system of the motor of the solar tracker (33).