WO2014207718A1

WO2014207718A1 - Managing electronic circuit of an electric energy storing device and an electric storage and distribution system

Info

Publication number: WO2014207718A1
Application number: PCT/IB2014/062669
Authority: WO
Inventors: Giovanni Sala; Gabriele Rossato; Francesco Gargiuolo; Davide Sala; Alberto Limonta; Maurizio Egidio Brioschi; Michele ROSSATO; Giuseppe Carmine PERETTO
Original assignee: Sonolis S.R.L.
Priority date: 2013-06-28
Filing date: 2014-06-27
Publication date: 2014-12-31
Also published as: ITMI20131089A1; EP3014737A1

Abstract

A management electronic circuit (112; 113) of an external electric power storage device (SC; LB) is described, comprising: a supply terminal (204; 205) connectable to the storage device for receiving a supply electric voltage of the management circuit; a measurement and command module (200) configured for: measuring an electric quantity associated to the storage device, comparing the electric quantity with a threshold value and generating a dissipation command signal (S_Sw2); an electric power dissipation module (201) connectable/disconnectable to/from the storage device by the dissipation command signal (S_Sw2); a first switching device (202) configured for connecting/disconnecting the managing circuit to/from the supply terminal (204, 205) and selectively switch it to an active configuration and to a stand-by configuration.

Description

TITLE : MANAGING ELECTRONIC CIRCUIT OF AN ELECTRIC ENERGY STORING DEVICE AND AN ELECTRIC STORAGE AND DISTRIBUTION SYSTEM"

D E S C R I P T I ON

Technical field of the invention

The present invention refers to the management of electric power storing devices such as, for example, supercapacitors or chemical batteries, for example, lithium batteries.

Prior art

It is known to provide in residential or industrial structures the supply of electric power by renewable sources (such as photovoltaic panels, wind farms, photovoltaic or geothermal fields) parallel to the local power grid. Due to their nature, renewable sources are capable of supplying power only under certain circumstances. For example, the photovoltaic panels are capable to supply electric power only in the daytime, while the wind farms only in the presence of wind. In the absence of a sufficient supply of electric power from the renewable sources, the electric current is withdrawn from the local power grid.

The known systems are devised for putting the alternative source before the power grid, in other words to supply electric power to the users by withdrawing it, if it is possible, from an alternative source.

Since often the output peaks of the alternative source do not coincide with the peaks of the user demands, it happens that, in the presence of a low power output of the alternative source with respect to the user demand, the power must be withdrawn from the power grid, while in the presence of a high power output with respect to the user demand, the excess of power is given to the power grid, without storing it.

Therefore, the known systems generally are not capable of storing the power produced by the alternative sources in periods of low demands of the users and to give it back when is needed. Therefore, the dependence on the power grid is still substantial.

Although batteries were associated for storing power, the use of the latter is very problematic. Indeed, known batteries, in addition to generally have short cycle lives and "slow" recharging times, require a complex maintenance and entail therefore high costs, which erase the economical advantages related to the exploitation of power sources alternative to the power grid.

Specifically, in the current residential or industrial structures, provided with alternative power sources, the management of such batteries is not satisfying not even in terms of duration of the battery charge when this is not used.

Summary of the invention

Therefore, an object of the present invention is to make available an electronic circuit for managing an electric power storing device which, in addition to avoid damages to the storing device during the charging step, increases - with respect to what happens according to the known art - the duration of the charge stored in the storing device itself.

This and other objects are met by a system for distributing and storing electric power according to claim 1. Dependent claims refer to particular embodiments. Claim 10 and dependent claim 11 define a system for distributing and storing electric power.

Brief description of the drawings

To better understand the invention and appreciate its advantages, in the following some exemplifying non limiting embodiments thereof will be described with reference to the attached drawings, wherein:

Figure 1 is a schematic view of a system for distributing and storing electric power according to a possible embodiment of the invention;

Figure 2 schematically shows a particular embodiment of an electronic circuit for managing an electric power storing device useable in the system of Figure 1; Figure 3 shows a first example of said electronic management circuit;

Figure 4 shows a second example of said electronic management circuit.

Detailed description of the invention

With reference to Figure 1, an electric power distributing and storing system has been generally indicated by the reference 100. The system 100 is suitable for being installed in residential structures, such as for examples condominiums or private houses, or industrial structures, such as manufacturing plants or photovoltaic fields.

The system 100 is configured for supplying electric power to one or more users 101, for example houses of the residential structure or departments of the industrial structure, or for reselling it through the grid to a public or private energetic provider, by withdrawing it from different sources. To this end, the system 100 comprises at least one output terminal 102 for supplying the electric power to users 101.

The system 100 comprises at least one first input terminal 103 connectable to the local power grid for withdrawing electric power from the latter. Figure 1 schematically shows the local power grid by reference 105. The current supplied by the local power grid 105 is usually alternate current.

Further, the system 100 comprises at least one second input terminal 106 which is connected or connectable to at least one electric power source 107 alternative to the local power grid, for withdrawing electric power from the latter. Particularly, the alternative power source 107 can comprise renewable power sources such as for example photovoltaic panels, wind farms or geothermal sources, etcetera.

According to a possible embodiment, the system 100 comprises at least one third input terminal 108 connected or connectable to an auxiliary generation system 109, for withdrawing power from the latter for example in case of fails, emergency, maintenance or insufficient power output of other sources. For example, the auxiliary generation system 109 can comprise power plants or co-generators, for example based on fossil fuel or LPG. The activation of the auxiliary generation system 109 can be for example managed by an auxiliary control module 11.

The system 100 comprises a first input/output terminal 110 connected or connectable to a first storage system 8 for storing electric power in the latter and for withdrawing the stored electric power from the same. Further, the system 100 comprises a second input/output 111 connected or connectable to a second storage system 9 for storing electric power from the latter and for withdrawing electric power stored by the same. The first 8 and second storage systems 9 are different from each other. Preferably, the first storage system 8 is characterized by charging/discharging rates higher than the ones of the second storage system, but by smaller amounts of stored power.

Particularly, the first storage system 8 comprises one or more storage devices such as preferably one or more supercapacitors serially and/or parallel connected to each other. The term "supercapacitors" means a type of per se known battery harnessing the capacity of storing electric power from the capacitors. With respect to the chemical-type batteries, the supercapacitors have shorter charging and discharging times; however they are capable of storing a power amount smaller than the one of the chemical batteries.

The second storage system 9 comprises one or more further storage devices such as, preferably, one or more chemical-type batteries, which are also in series and/or parallel, still more preferably one or more lithium batteries, for example LiFeP04 type batteries.

Advantageously, a first management circuit 112 and a second management circuit 113 are respectively associated to the first storage system 8 and the second storage system 9. Such management circuits 112 and 113 preferably comprise one or more electronic devices associated to each element of the storage systems 8 and 9 (for example associated to each supercapacitor and to each lithium battery) and having the function of maintaining, during the charge, the recharging voltage between predetermined values, particularly the function of supplying the storage system with voltage values substantially equal to the nominal voltage. In this way, overvoltages impairing for example the duration and operability of the elements of the storage system are avoided. The management circuits 112 and 113 are of the active-type, in other words controllably activable by switching their electronic inner components (particularly a MOSFET transistor and microprocessors). Further characteristics and functions of the balancing system will be described in the following.

Advantageously, the system 100 comprises a module 1 for filtering the electric signal from the local power grid 104. According to a possible embodiment, the filtering module 1 comprises one or more passive filters suitable for reducing possible peaks or noises (for example RFI or EMI noises) .

More advantageously, the system 100 comprises a transformer module 2 for modifying the voltage exiting the filtering module 1, in a different voltage, adapted to be managed by the system 100. The transformer module 2 can comprise transformers of different types, for example electromechanical-type transformers or electronic-type transformers, per se known, preferably of the step-up type. According to a possible embodiment, the transformer module 2 comprises an isolation transformer, for example a toroidal electromechanical transformer, having an electric isolation between the windings such to electrically isolate the power grid 105 from users 101. Alternatively, the transformer module 2 can comprise an electronic-type "switching-type" transformer. The voltage exiting the transformer module

2 is preferably comprised between 24 ACV and 1000 ACV. The system 100 comprises a command module 3 configured for supplying electric power to the users 101 by alternatively withdrawing it from the alternative electric power source 107, from the first storage system 8, from the second storage system 9, from the local power grid 105, or possibly from the auxiliary generation system 109, according to modes that will be described in the following. Further, the command module

3 manages the recharge of the first 8 and second storage systems 9, according to modes that will be also described in the following, by withdrawing the necessary power from the electric alternative source 107, from the local power grid 105, or possibly from the auxiliary generation system 109.

According to a possible embodiment, the command module

3 comprises an electronic board provided with a microprocessor .

Preferably, the system 100 comprises a module 4 for preprocessing the currents from the alternative power source 107. It has the function of equally apportioning the voltages of the currents from such source 107, in order to particularly avoid overloads or power losses due to voltage differences. With reference for example to photovoltaic panel modules, each of them could supply current at a different voltage. The preprocessing module

4 parallel arranges such modules, in order to make uniform the voltages. The preprocessing module 4 comprises for example power diodes and smoothing capacitors. The voltage of the current exiting the preprocessing module 4 is preferably comprised between 80 and 1000 DCV.

Preferably, between the command module 3 and users 101, the system 100 comprises a module for processing the output current 7. Such module 7 has the function of taking the current exiting the command module 3 to values of voltage and intensity suitable for the users. Further, the module 7 is capable of converting the direct current into alternate current in case the users 101 operate in direct current. According to a possible embodiment, the direct current processing module 7 comprises an inverter system. Preferably, the currents exiting the processing module 7 have a voltage comprised between 12 ACV and 560 ACV. Alternatively, they can have a voltage comprised between 5 DCV and 2000 DCV.

Advantageously, the system 100 comprises a first 5 and second recharging modules 6, which are respectively associated to the first 8 and second storage systems 9. The first 5 and second recharging modules 6 are driven by the command module 3 and have the function of managing the recharging of the first 8 and second storage systems 9. Particularly, they act on the charging currents as supplied by the command module 3 and make them suitable for the storage systems 8 and 9. Preferably, the voltages of the currents exiting the command module 3 directed towards the recharging modules 5 and 6 are comprised between 80 and 1000 DCV. According to a possible embodiment, the recharging modules 5 and 6 comprise respective electronic boards provided with a microprocessor. Advantageously, the recharging modules 5 and 6 adjust the charging currents of the storage systems based on the pulse width modulation criterion (PWM), with a frequency preferably comprised between 10 Hz and 25 KHz. Further advantageously, the recharging modules 5 and 6 are configured for activating the first 112 and second management circuits 113, associated respectively to the first 8 and second storage systems 9, only during the charging of the latter.

Further advantageously, the recharging modules 5 and 6 monitor the temperatures and maximum currents of the first 8 and second storage systems 9, in order to avoid damages to the same.

According to a possible embodiment, the system 100 comprises an user interface module 10 for enabling an user to manage the system 100 and for displaying the operative parameters thereof. The user interface module 10 can for example comprise a PLC or a microprocessor, and a display system, for example a screen. The user interface module. 10 is communicating with at least some of the system modules or devices. Particularly, it preferably communicates with the transformer module 2, with the command module 3, with the preprocessing module 4, with the first recharging module 5, with the second recharging module 6, with the first storage system 8, and with the second storage system 9. The data transmission between the above mentioned modules and user interface module 10 can be implemented by a wired or wireless system.

According to a possible embodiment, proportional switches between the command module 3 and respectively: the transformer module 2 and/or the first recharging module 5 and/or the second recharging module 6 can be provided .

The modes of managing the power flows by the command module 3, particularly the modes of selecting the power source for supplying the required electric current from users 101, and also the modes of recharging the first 8 and second storage system 9 will be described.

The command module 3, given a certain instant power demand from an user, withdraws such power from one source at a time according to a predetermined order. Particularly, the control module 3 is configured for supplying electric power to the users 101 by withdrawing it until the required instant power amount is reached in the following order:

1) from the alternative electric power source 107;

2) from the first storage system 8 ;

3) from the second storage system 9;

4) from the local power grid 105.

Therefore, first of all the electric power for the users 101 is withdrawn from the alternative electric power source 107. If the instant power amount available from the electric power alternative source 107 is not sufficient to meet the need of the users, the power is withdrawn, in addition to the alternative electric power source 107, from the first storage system 8. If the total instant power amount available from the alternative electric power source 107 and from the first storage system 8 is not sufficient to meet the need of the users, the power is withdrawn, in addition to the alternative electric power source 107 and to the first storage system 8, from the second storage system 9. If the total instant power amount available from the alternative electric power source 107, from the first storage system 8 and from the second storage system 9 is not sufficient to meet the need of the users, the power is withdrawn, in addition to the alternative electric power source 107, to the first storage system 8, and to the second storage system 9, . from the local power grid 105.

In case no one of the above mentioned power sources is available, or has reached the suppliable maximum instant power amount, the control module 5 can withdraw further power from the auxiliary generation system 109.

As it will be apparent to a person skilled in the art, the command module 3 acts in order to withdraw power from the local power grid 105 and/or from the auxiliary generation system 109 only if it is necessary.

It is important to observe that the first 8 and second storage systems 9 are successively used, in other words the power is demanded to the second storage system 9 only when the first storage system 8 is no more capable of supplying it. This power withdrawing mode causes the first storage system 8 to be more harnessed than the second system 9, which therefore will have a long life and will need a limited maintenance. The use of supercapacitors in the first storage system 8 and of chemical batteries, particularly lithium batteries, in the second storage system 8, is particularly advantageous with reference to this harnessing criterion of the storage systems. Indeed, the lithium batteries which are more jeopardized by the repeated charging cycles than the supercapacitors, are harnessed less than the latter.

Therefore, in case the required instant power demanded by the user 101 is greater than the instant power available from the alternative power sources 107, the charges of the first 8 and second storage systems 9 are successively harnessed.

Instead, in case the instant power demanded by the users 101 is equal (except for power losses inside the system 100) to the instant power supplied by the alternative power source 107, all the power is withdrawn from the latter.

In case the instant power demanded by the users 101 is less than the instant power supplied by the alternative power source 107, the users 105 are supplied by all the required power coming from the alternative power source 107, and the excess of power is harnessed for charging the storage systems 8 and 9.

Advantageously, the control module 3 is configured also for recharging the storage systems 8 and 9 according to a predetermined order. Particularly, it is performed a complete recharge, or to a predetermined charge level, before the first storage system 8. Only when this operation ends, the second storage system 9 is completely recharged or to a maximum predetermined level .

Therefore, also during the recharging processes, the first storage system 8 has the priority over the second storage system 9. Indeed, the first storage system 8, as previously described, is more often subjected to a discharge and therefore is more often recharged. The second storage system 9 is in this way further preserved since is recharged for a number of times less than the first storage system. Moreover, the recharging logic of the storage systems is particularly advantageous in combination with the use of superconductors in the first storage system 8 and of chemical batteries, particularly lithium batteries, in the second storage system 9. The latter, indeed, since are more subjected to wear due to the repeated charging and discharging cycles, are recharged a number of times less than the supercapacitors , which instead are less subjected to wear due to repeated cycles. Moreover, the recharging modes ensure therefore a long duration of the system 100.

It is observed that in the present description and in the attached claims, terms such as "instant power" or "amount of instant power" refer to quantities such as the electric power or similar quantities.

Further, it is observed in the present description and in the attached claims, the system 100 and also the elements indicated by the term "module" can be implemented by hardware devices (for example central units), by software or by a combination of hardware and software .

Figure 2 schematically shows an example of an embodiment of the first management circuit 112, suppliable by a supercapacitor SC and included in the first storage system 8. The first management circuit 112 is connected to the first supercapacitor SC by a first supply terminal 204 and a second supply terminal 205.

The diagram of Figure 2 is also useable for implementing the second management circuit 113, suppliable by a chemical battery LB, such as a lithium battery, included in the second management device 9. Preferably, it is observed that the first management circuit 112 is dedicated to a single supercapacitor SC and the second management circuit 113 is dedicated to a single lithium battery LB.

The first management circuit 112 comprises: a measurement and command module 200 (MEAS-COMM) , an electric power dissipation module 201 (DISSIP-MOD) and a first switching device 202 (SW1).

The measurement and command module 200 is configured for measuring an electric quantity associated to the supercapacitor SC and comparing it with a threshold value. Based on such comparison, the measurement and command module 200 is capable of generating a dissipation command signal S_SW2-

The measurement and command module 200 can comprise solid-state components (such as for example: transistors and diodes in possible different configurations), electronic passive components (for example: resistors, capacitors and inductors), electronic circuits (comparators, power supplies, stabilizers, logic circuits) , implemented by discrete components and/or integrated circuits. Particularly, the measurement and command module 200 can be also provided with a microprocessor .

Particularly, the measurement and command module 200 is configured for measuring an electric voltage vi across the supercapacitor SC (or across the lithium battery LB) and comparing it with a threshold value V_T. Particularly, as in the case of the lithium batteries LB, the measurement and command module 200 can also operate for controlling the electric current in the same battery.

The electric power dissipation module 201 is connectable/disconnectable to/from the supercapacitor SC based on the dissipation command signal S_SW2 - According to an example of embodiment, the electric power dissipation module 201 is provided with one or more resistors ensuring the power dissipation.

The first management circuit 112 can comprise a second switching device 203, which based on the dissipation command signal S_Sw2 connects/disconnects the dissipation module 201 to/from the supercapacitor SC. Such second switching device 203 can include a BJT-type transistor (Bipolar Junction Transistor) or a MOSFET-type transistor (Metal Oxide Semiconductor Field Effect Transistor) or implemented with another technology.

The first switching device 202 is connected to the first supply terminal 204 and to the second supply terminal 205 and is driveable by an activation/deactivation signal S_en-_di_S generated outside the first management module 112.

The first switching device 202 is configured for connecting/disconnecting the first management circuit 112 from the supercapacitor SC and selectively switching it in an active and stand-by configuration. The activation/deactivation signal S_en__di_S of the first management circuit 112 is generateable by the first recharging module 5 while for the second management circuit 113 is generateable by the second recharging module 6. The activation/deactivation signal S_en-_di_s can take, for example, two logical levels: a first level commanding the closure of the first switching device 202 and a second level commanding the opening of the first switching device 202.

The first switching device 202 can comprise a transistor and, preferably, is implemented by an optoisolator enabling, besides the switching between a closure state and an opening state of the optoisolator, also a galvanic insulation between the first management circuit 112 and the first recharging module 5 supplying the act ivation/deactivation signal S_en-_di_S.

According to the diagram of Figure 2, the measurement and command module 200 and the second switching device 203 receive the electric supply from the supercapacitor SC by the first and second supply terminals 204 and 205 and the first switching device 202, when is in the closure state. The first switching device 202 is connected to the second switching device 203 by two first supply lines 206. The second switching device 203 is connected to the dissipation module 201 by two second supply lines 207.

The measurement and command module 200 is connectable to the supercapacitor SC both for being supplied and for measuring the electric quantity of interest, such as the voltage Vi between the first 204 and second supply terminals 205. For example, such connection is implemented by third supply lines 208, connected to the first supply lines 206, exiting the first switching device 202 or by another suitable connection.

Preferably, the measurement and control module 200 is also configured for supplying outside the first management circuit 112, a charge completed signal S_Chr, indicative of the fact the electric voltage i has reached the charge nominal value of the supercapacitor. The charge completed signal S_chr can be read by the first recharge module 5 which enables the activation/deactivation signal S_en-dis ·

An example of the operation of the first management module 112 of Figure 2 will be now described. Firstly, the recharging module 5 switches to the closure state the first switching device. 202 by a suitable logic level of the activation/deactivation signal S_en-dis- In this way, the first management circuit 112 is active and is supplied by the supercapacitor SC. In such case, the supercapacitor SC is recharged by the recharging module 5 which withdraws the electric power from the control module 3. During the charge, the second switching device 203 is in the open state and therefore the dissipation module 201 is not connected to the second supply lines 206.

During the charge, the measurement and command module 200 monitors the electric voltage vi at the first and second supply terminals 204 and 205 and, if this reaches the threshold value V_T, activates the second switching device 203 which connects the second supply lines 206 to the third supply lines 207, by causing the excess of electric power stored in the supercapacitor SC to be dissipated inside the dissipation module 201. So, the supercapacitor SC is prevented from being damaged during the recharging process.

When it is reached the threshold value V_T (representative of a charge nominal value of the supercapacitor SC and, preferably, greater than this one) the measurement and command module 200 supplies outside the management circuit 112 the charge completed signal S_chr, which takes a logic value indicative of the fact that the electric voltage vi has reached the charge nominal value of the supercapacitor SC. For example, the nominal charge value is equal to 2.7 V and the value of the threshold voltage V_x is equal to 2.8 V.

The first recharging module 5 (Figure 1) reads the charge completed signal S_Chr and enables the activation/deactivation signal S_en-dis so that the latter opens the first switching device 202. Upon the opening of the first switching device 202, the electric supply provided by the supercapacitor SC to the first management circuit 112 is interrupted and the latter is switched in a stand-by state.

In this way, when the charge of the supercapacitor SC ends, the first management circuit 112 is switched to the stand-by state in which it does not absorb electric power from the supercapacitor SC. Therefore, the first management circuit 112 enables to obtain a longer duration of the charge and a shorter duration of the supercapacitor SC auto-discharge.

Figure 3 shows a first particular example of an embodiment of the first management circuit 112 useable, preferably, for managing the supercapacitor SC. The measurement and command module 200 comprises a monitoring circuit 209 and a command device Tl. The monitoring circuit 209 is electrically connected to the first and second supply terminals 204 and 205, which in turn are connected to the supercapacitor SC (not shown in Figure 3) .

The monitoring circuit 209 is such to generate a threshold exceeding signal S_th (a voltage signal, for example) to be supplied to the command device Tl. According to the described example, the monitoring circuit 209 is provided with an adjustable impedance device (such as for example a trimmer) R_tr by which the threshold exceeding signal S_th is generated.

More particularly, the monitoring circuit 209 includes a sensor circuit electrically connected to the first supply terminal 204 and to the trimmer R_tr- Specifically, such sensor circuit comprises a first resistor Rl having a terminal connected to a first supply terminal 204 and a second terminal connected to a first node Nl which in turn is connected to a parallel circuit including a first capacitor CI and second resistor R2, connected between the first node Nl and a second node N2. A second capacitor C2 is connected between the first node Nl and the second supply terminal 205. The second node N2 is also connected to a third resistor R3, connected to a first terminal 213 of the trimmer R_tr/ which is also connected to a second terminal 214, which in turn is connected to a third node N3.

Preferably, a precision programmable voltage diode VRl is connected between the first node Nl and the third node N3. Such programmable voltage diode VRl helps to ^■set the threshold voltage V_T. The trimmer R_tr is provided with a first adjustment terminal TR1 and with a second adjustment terminal TR2. modifying the value of the resistance of the trimmer itself. A third capacitor C3 is connected between the third node N3 and the second supply terminal 205. Also the second and third capacitors C2 and C3 and the resistors Rl, R2, R3 enable to set the threshold voltage.

The command device Tl comprises, according to the described example, a first transistor, for example, of the bipolar-type (Bipolar Junction Transistor) , PNP, having a base terminal connected to the first node Nl, in order to receive the threshold exceeding signal S_thr an emitter terminal connected to the first supply terminal 204 and a collector terminal connected to the first switching device 202 and such to supply the dissipation command signal S_Sw-

Preferably, a fourth capacitor C4 is connected between the collector terminal and the emitter one of the first transistor Tl, in order to have a filtering function with reference to the_. current peaks or transients occurring in the first management circuit 112 and caused, for example, by the PWM recharging mode or by insertion transistors associated to external electromechanical remote control switches.

According to the example in Figure 3, the switching device 202 includes a second transistor T2, for example, of the bipolar-type, NPN, and having a collector terminal connected to the electric power dissipation module 201 and an emitter terminal connected to the second supply terminal 205. Advantageously, the second transistor T2 is obtained by a Darlington transistor pair and therefore offers a high gain. A fourth resistor R4 is connected between the base terminal of the second transistor T2 and a fourth node N4 connected to the collector terminal of the first transistor Tl. A fifth resistor R5 is connected between the emitter terminal of the second transistor T2 and the fourth node N4.

The electric power dissipation module 201, exemplifyingly shown in Figure 3, includes a plurality of dissipation resistors R_ID-R _D, for example, parallel connected, and each connected between a first supply terminal 204 and a node ND, connected to the collector terminal of the second transistor T2.

According to a particular embodiment in Figure 3, the first switching device 202 comprises a first optoisolator OKI including first command terminals 211, of which one is provided with a sixth resistor R6, and with first output terminals 212.

The first command terminals 211 are suitable for receiving the activation/deactivation signal S_en-dis r as a command voltage applied to first input terminals JP1 and JP2. Based on the electric voltage associated to the activation/deactivation signal S_en-_dis _f the first optoisolator will close or open the first output terminals 212 by connecting or disconnecting the third node N3 to/from the second supply terminal 205.

According to a particular example, the first management circuit 112 is also provided with a second optoisolator OK2 having second command terminals 215 and second output terminals JP3 and JP . One of said second command terminals is connected to a fifth node N5 while the other terminal of said second command terminals 215 is connected to the first supply terminal 204, by a seventh resistor R7. The fifth node N5 is connected both to the node ND of the dissipation module 201 and to a cathode of a LED (Light Emitting Diode) photodiode 216 having one anode thereof connected to the first supply terminal 204, by an eighth resistor R8. A protection diode Dl is connected between the first supply terminal 204, common to the dissipation resistors RID~ RND, and the second supply terminal 205.

With reference to its operation, the first management circuit 112 of Figure 3 is switched to the active configuration by closing the first output terminals 212 of the first optoisolator OKI.

In such a configuration, the circuit 209 is supplied by the electric power supplied by the supercapacitor SC. While the supercapacitor SC is charging, the monitoring circuit 209 monitors the voltage across the supercapacitor SC. When such voltage arrives to a threshold value V_T equal to the one set by the trimmer R_{T R} , related to the maximum charging voltage of the supercapacitor SC, a negative potential difference forms between the base terminal and the emitter terminal of the first transistor Tl, which switches the first transistor Tl in saturation and this turns on the second transistor T2, which is initially turned off.

The conduction of the second transistor T2 connects the node ND of the dissipation module 201 to the second supply terminal 204, causing the excess of electric power which could destroy the supercapacitor SC, to be dissipated in the dissipation resistors R_ID ^_R_ND-

When it is reached the maximum charging voltage between the supply terminals 204 and 205, the LED photodiode 216 emits a light signal and the second optoisolator OK2 closes, by generating at the second output terminals JP3 and JP4 the charge completed signal S_chr, which is made available to the first recharging module 5 (Figure 1) .

Therefore, the first recharging module 5 supplies at the first command terminals JP1 and JPT2 the activation/deactivation signal S_en-dis as a voltage so that the first optoisolator OKI opens its first output terminals 212 so that the first management circuit 112 is switched to a stand-by configuration.

Figure 4 shows a second example of embodiment of the circuit in Figure 2, particularly adapted to implement the second management circuit 113 operatively associated to the lithium battery LB. Components or signals similar or identical to the ones previously described will be indicated in Figure 4 by the same numerical references used in the previous figures.

The lithium battery LB (not shown in Figure 4) is connected between the first supply terminal 204 and the second supply terminal 205. The first switching device

202 of Figure 4 is analogous to the one described with reference to Figure 3 and comprises the previously described optoisolator OKI. The second switching device

203 in Figure 4 includes a switching transistor Q4 (a N- channel enhancement MOSFET-type transistor, for example) having a source terminal S, a drain terminal C and a gate terminal G.

The dissipation module 201 is implemented in Figure 4 by a dissipation resistor RD connected between the first supply terminal 204 and a dissipation terminal TR₇ connectable to the second dissipation terminal 205 by the second switching device 203.

The measurement and command module 200 in Figure 4 comprises a processing unit 400 (PU) such as, for example, a microprocessor, storing a software and/or a firmware determining the operation mode. The microprocessor 400 is suitable for detecting the electric voltage value across the lithium battery LB, for example, by a first filtering inductor LI, connected to the first supply terminal 204 and to a read input Ii of the microprocessor 400. Further, the microprocessor 400 is configured for comparing the detected voltage value with a predetermined threshold value and for generating at a first output port Oul the threshold exceeding signal S_th-

Further, the measurement and command module 200 is provided with a pilot device or driver IC3, connected to the first output port Oul of the microprocessor 400, for receiving the threshold exceeding signal S_th and supplying at the gate terminal G of the MOSFET Q4 the dissipation command signal S_Sw2 ·

The driver IC, commanded by the microprocessor 400, generates an electric voltage (for example, with a PWM trend) adapted to turn on and turn off the MOSFET Q . When the MOSFET Q4 is turned on, the first supply terminal 204 and the second supply terminal 205 are connected to the dissipation resistor RD, discharging the excess of electric power of the lithium battery LB and causing a drop of the electric voltage.

During the battery discharge by the dissipation resistor RD, the microprocessor 400 is further suitable for comparing the electric current obtainable from the lithium battery LB with a current threshold value. In case such electric current decreases below a predetermined value (for example equal to 20 A) the microprocessor 400 commands the opening of the MOSFET Q4, in this way it is interrupted the discharge of the lithium battery LB. Indeed, if the electric current of the lithium battery LB drops below a nominal value, the battery itself will be damaged.

To this end, the measurement and command module 200 is also provided with a current sensor device IC4 capable of detecting the current forming during the battery LB discharge in the dissipation resistor RD and providing a read signal VI_R to a second input 12 of microprocessor 400, by a second inductor L2. Based on the current value indicated by the read signal VI_R, the microprocessor 400 can turn off the MOSFET transistor Q4 by the driver IC3, or maintain it turned on by interrupting or not the dissipation. For example, the current sensor device IC4 is a Hall effect linear sensor which converts the current flowing through it, into a voltage VI_R (comprised between 0 and 5 V, for example) .

The measurement and command module 200, shown in Figure 4, is also provided with a second optoisolator OK2, analogous to the one in Figure 3, which closes by generating at its second output terminals JP3 and JP4 the recharge completed signal S_chr, of the lithium battery, which is made available at the second recharging module 6 (Figure 1) . Such second optoisolator OK2 is commanded by the microprocessor 400 by warning signals provided at corresponding outputs O_ua and O_ub.

Advantageously, the measurement and command module 200 comprises a supply circuit 401, for example a step-up type switching power supply operating at 3.3 kHz. Such supply circuit 401 is suppliable by the direct current electric voltage (equal to 3.2 V, for example) supplied by the lithium battery LB and configured for supplying a stabilized voltage (for example, at 5 V) to the microprocessor 400.

According to the example shown in Figure 4, the supply circuit 401 comprises an oscillation inductor L_osc connected to a further switching device Q2, such as a bipolar transistor, and to an eighth node N8. Such further switching device Q2 is provided with a respective emitter terminal connected to the first supply terminal 204, a respective base terminal connected to one of the output terminals 212 of the first optoisolator OKI, and a respective, collector terminal connected to a terminal of the oscillation inductor L_osc. The further switching device Q2 enables to deliver or interrupt the supply to/of the supply circuit 401 and therefore to/of the second management circuit 113.

Further, the supply circuit 401 comprises an oscillation amplifier T_osc which is oscillated (at 3.3 kHz according to the example) by the oscillation inductor L_osc. For example, the oscillation amplifier T_OSc is obtained by a Darlington transistor pair.

According to the particular embodiment of Figure 4, the oscillation transistor T_osc comprises a collector terminal connected to the eighth node N8, an emitter terminal connected to the ground GND, and a base terminal connected, by an eighth resistor R8, to a square wave generator 402.

The square wave generator 402 controls, by the generated square wave, the switching of the oscillation Darlington transistor T_osc between the closure and opening. Such square wave has, according to the described example, a frequency of 3.3 kHz.

According to a particular embodiment, the square wave generator 402 is a Colpitts local oscillator and comprises a first oscillation transistor T_osl and a second oscillation transistor T_OS2, for example both of a bipolar type. The first oscillation transistor T_osi is provided with: en emitter terminal connected to the ground GND, a collector terminal connected to a ninth node N9 and a base terminal connected to a tenth node N10.

The ninth node N9 is connected, by a ninth resistor R9, to an eleventh node Nil, which in turn is connected to the collector terminal of the further switching device Q2. The ninth node N9 is also connected, by a first oscillation capacitor C_osi, to a twelfth node N12. The tenth node N10 is connected to the eleventh node Nil, by a tenth resistor RIO.

The second oscillation transistor T_0S2 is provided with: an emitter terminal connected to the ground GND, a collector terminal connected to a thirteenth node N13 and to a base terminal, connected to the twelfth node N12. The twelfth node N12 is connected, by an eleventh resistor Rll, to the eleventh node Nil. The thirteenth node N13 is connected, by a twelfth resistor R12, to the eleventh node Nil.

The eighth node N8 is connected, by a diode D, to a charge/discharge capacitor C_Cd (also connected to the ground GND) which is charged by the electric power supplied by the oscillation inductor L_osc. The voltage across the charge/discharge capacitor C_cd can reach, for example, the maximum value of 20 V.

The charge/discharge capacitor C_Cdie is connected to a power supply IC2 (for example an integrated 7805 type) which converts the voltage supplied by the charge/discharge capacitor C_Cd to a stable voltage having a smaller maximum value (5 V, for example) and makes it available to a supply input IA of the microprocessor 400. Further, the voltage at the output of the power supply IC2 is delivered also to the current sensor device IC4.

From the above given description, a person skilled in the art can appreciate that, the charge and discharge management modes of the storage systems ensure them a long life and therefore a long duration of the overall system.

Further, it is observed that the system according to the invention enables to store power from sources alternative to the power grid and therefore enables to substantially reduce the necessity of withdrawing current from the local power grid or from auxiliary generation systems by harnessing the features of the supercapacitors which can be recharged in very short times which enable to store a power amount greater than what was possible according to the prior art.

To the described embodiments of the system for distributing and storing electric power according to the invention, a person skilled in the art, in order to meet specific contingent needs, can introduce several additions, modifications, or substitutions of elements with other operatively equivalent, without departing from the scope of the attached claims.

Numerical references used in the figures:

- system for distributing and storing electric power 100 one or more users 101

at least one output terminal 102

local power grid 105

at least one second input terminal 106

at least one alternative electric power source 107 at least one third input terminal 108

auxiliary generation system 109

auxiliary control module 11

first input/output terminal 110

first storage system 8 ( supercapacitor )

second input/output terminal 111

second storage system 9

first balancing system 112

second balancing system 113

filtering module 1

transformer module 2

control module 3

preprocessing module 4

output current processing module 7

a first 5 and second recharge modules 6

user interface module 10

a measurement and command module 200

electric power dissipation module 201 (DISSIP-MOD) first switching device 202 (SWl)

dissipation command signal S_{S W}2 electric voltage Vi

supercapacitor SC

lithium battery LB

second switching device 203

activation/deactivation signal S_en__di_S

first and second supply terminals 204 and 205 two first supply lines 206

two second supply lines 207

third supply lines 208

monitoring circuit 209

command device Tl

threshold exceeding signal S_th

trimmer R_tr

connected sensor circuit

first resistor Rl

first capacitor CI

second resistor R2

second capacitor C2

third resistor R3

first adjustment terminal TR1

second adjustment terminal TR2

third capacitor C3

programmable voltage diode VRl

first node Nl

second node N2 fourth capacitor C4

fourth resistor R4

third node N3

fourth node N4

second transistor T2

fifth resistor R5

sixth resistor R6

dissipation resistors RI_D- RND

first optoisolator OKI

first command terminals 211

first output terminals 212

first input terminals JPl and JP2

first terminal 213

second terminal 214

first optoisolator OKI

second optoisolator OK2

recharge completed signal S_chr

second command terminals 215

second output terminals JP3 and JP4

fifth node N5

ND node of the dissipation module 201

seventh resistor R7

photodiode 216

switching transistor Q4 (MOSFET Q4)

source terminal S, drain terminal C, gate terminal G first output port Oul

piloting device or driver IC3 dissipation resistor RD a current sensor device IC4 read signal VI_R

second input 12

second inductor L2

outputs O_ua and O_ub

supply circuit 401

oscillation inductor L_osc further switching device Q2 eighth node N8

oscillation amplifier T_osc eighth resistor R8

square wave generator 402 first oscillation transistor ' second oscillation transistor ninth node N9

tenth node N10

eleventh node Nil

twelfth node N12

thirteenth node N13

ninth resistor R9

tenth resistor RIO

eleventh resistor Rll - twelfth resistor R12

- diode D

- charge/discharge capacitor C_Cd

- power supply IC2

- supply input IA

Claims

C L A I S

1. Electronic management circuit (112; 113) for an electric power storage device (SC; LB) external to the circuit, comprising:

a supply terminal (204; 205) connectable to the storage device for receiving an electric supply voltage for the management circuit;

a measurement and command module (200) configured to: measure an electrical quantity associated with the. storage device, compare the electrical quantity with a threshold value and generate a dissipation command signal (S_SW2 ) ;

an electric power dissipation module (201) connectable/detachable to/from the storage device by the dissipation command signal (S_SW2 ) ;

a first switching device (202) configured to connect /disconnect the management circuit to/from supply terminal (204, 205) and selectively switch it between an active configuration and a stand-by configuration.

2. Management circuit (112; 113) according to claim 1, wherein first switching device (202) is configured to connect/disconnect the management circuit to/from supply terminal (204, 205) based on a command signal ( S_en-_dis ) generated outside the management circuit.

3. Management circuit (112; 113) according to at least one the preceding claims, further comprising a second switching device (203), switchable, through said dissipation command signal { S_sw2 ) , to connect /disconnect dissipation module (201) to/from storage device (SC; LB) .

4. Management circuit (112; 113) according to claim

2, wherein said first switching device (202) comprises: an optoisolator (OKI) having command terminals (211) configured to receive said command signal ( S_en-dis ) and output terminals (212) configured to connect /disconnect measurement and command module (200) to/from said supply terminal (204; 205) .

5. Management circuit (112; 113) according to claim

3, wherein said second switching device (203) comprises: a transistor (T2; Q4) having a command terminal designed to receive dissipation command signal (S_SW2) , a first output terminal connected to a supply terminal and second output terminal connected to dissipation module (201) .

6. Management circuit (112; 113) according at least to claim 1, wherein said measurement and command module (200) further comprises:

a monitoring module (209, 400) configured to generate a threshold exceeding signal ( S_th ) indicating that storage device (SC; LC) has reached the maximum value of an electric parameter;

a command module (Tl, IC3) configured to generate dissipation command signal (S_SW2) from threshold exceeding signal ( S_th ) ·

7. Management circuit (112; 113) according at least to claim 1, wherein said electric parameter is an electric voltage and the storage device is a supercapacitor (SC) or a chemical battery (LB) .

8. Management circuit (112; 113) according at least to claim 1, further comprising a signaling circuit (OK2) configured to generate a charge completed signal (S_chr) of said storage device (SC; LB) to be made available outside of the management device.

9. Management circuit (112; 113) according at least to claim 1, wherein said measurement and command module (200) comprises a microprocessor (400) and a power supply configured to provide an alternating and stabilized electric voltage to the microprocessor.

10. System (100) for distributing and storing electric power, comprising:

a first storage system (8; 9) including at least one electric power storage device (SC; LB) ; an electronic circuit (112; 113) for managing said storage device, wherein said electronic circuit is implemented according to at least one of the preceding claims .

11. System (100) for distributing and storing electric power, according to claim 10, further comprising:

a first input terminal (103) connectable to the local power grid (105) to withdraw power from it;

a second input terminal (106) connected or connectable to a power source (107) alternative to the local power grid (105), in particular, a sustainable source of energy, for withdrawing power from the latter; an output terminal (102) for supplying power to one or more users (101);

a first input/output terminal (110) connected or connectable to a first storage system (8) for storing electrical power therein and withdrawing power stored in the same;

a second input/output terminal (111) connected or connectable to a second storage system (9) for storing electrical power therein and withdrawing power stored in the same, the second storage system (9) being different in nature from the second storage system (8); a command module (3) configured such that it provides electrical power to the one or more users (101) withdrawing it, until it is reached the instantaneous quantity, successively required from:

1) alternative source of electric power (107);

2) first storage system (8);

3) second storage system (9);

4) local power grid (105).