FR3077690A1 - REGULATING THE OPERATING FREQUENCY OF A TRANSPORT NETWORK AND / OR DISTRIBUTION OF ELECTRICAL ENERGY - Google Patents

Abstract

The invention relates to the regulation of a frequency of a network (1) for transporting and / or distributing electricity from a predefined group comprising a plurality of units (US1 to US6) for storing / returning data. electrical energy, able to be individually controlled, when connected to the network (1), for injecting or withdrawing electrical energy from the network (1). In a system according to the invention, for each unit (US1 to US6) a first set of data relating to technical specifications associated with the unit is determined, a second set of data relating to a current state associated with the unit. unit, and a third set of data relating to usage preferences associated with at least one energy storage and retrieval unit. A control unit (2) selects, among the units (US1 to US6) of the group, those that are individually controlled according to a specific individual contribution in injection or withdrawal so that a specific sum of individual contributions corresponds to an overall instruction, said selection being a function of the data included in the first, second and third data sets; the selected units are simultaneously controlled so that each operates in landfill, respectively in charge, according to its specific individual contribution.

Description

REGULATI ON OF THE FREQUENCY OF OPERATION OF A NETWORK OF TRANSPORT AND / OR DI STRI BUTI ON OF ELECTRIC ENERGY

The present invention relates generally to the frequency regulation of a transport and / or distribution network of electrical energy, and more precisely to a method and a system of frequency regulation capable of selecting, from a predefined group of units. storage and restitution of energy, storage and restitution units of electrical energy controlled to inject or extract electrical energy from the electrical energy transport and / or distribution network, according to a global injection and / or withdrawal instruction.

Frequency regulation or adjustment is a mechanism put in place by transmission system operators and / or distributors of electrical energy in order to guarantee the frequency stability of their networks. It involves asking certain producers and / or consumers of electricity to modify part of their production and / or consumption in real time to help maintain the frequency of the electricity network at a target value. In France for example, the operating frequency of the electrical network is equal to 50 Hertz, with a tolerance which may possibly be equal to plus or minus 0.01 Hertz on this operating frequency. The frequency regulation mechanism is generally applied when the current frequency of the electricity network is outside the frequency band between 49.99 and 50.01 Hertz. FIG. 1 illustrates, by way of example, the temporal variation of the frequency of a transmission and / or distribution network (left curve) and the corresponding temporal variation of a setpoint aiming in all cases to reduce the frequency of the network at 50 Hertz.

In view of the critical nature of the mechanism, any actor wishing to participate in the frequency adjustment must meet very strict specifications. In particular, you have to be very responsive and available.

It is already known practice to solicit, either directly or through a service provider, users holding energy storage and restitution units, for example rechargeable batteries, which they connect to the power network. electricity to make their contribution to the frequency regulation service of the electricity network. The known principle consists in simultaneously requesting and in equal proportion the energy storage and restitution units of the users who are willing to participate in this service so that they follow a global instruction.

By way of example, FIG. 2 represents, in the form of a profile P in broken lines, the temporal evolution of a global setpoint, and FIG. 3 (a) illustrates the respective contributions in electricity injection requested to a group composed of five energy storage and restitution units (USi to US5) to follow the P profile. In this example, we have assumed that the five energy storage and restitution units are identical and able to inject / draw variable powers within a given power range. The horizontal axis representing time here represents four identical periods, each corresponding to a sampling period of the setpoint signal, which can vary from a tenth of a second to a few minutes. As can be seen in Figure 3 (a), the five energy storage and restitution units of the group are, for each period, used in equal proportion, and the sum of their respective individual contribution (in the example, contributions in power injection) corresponds to the global setpoint. Thus, each energy storage and release unit is controlled to inject a power equal to 200 Watts during the first period, 600 Watts during the second period, 400 Watts during the third period, and again at 200 Watts during the fourth period. In other words, each energy storage and release unit is controlled to follow the setpoint signal and any setpoint variation is treated by a corresponding variation in power at the level of each unit.

Such management of energy storage and restitution units for frequency regulation is simple to implement since the action of each unit is a function (homothetic type) of the frequency, which can be measured on site , and does not take into account the action which is requested from the other storage units, and poses a certain number of problems arising mainly from the fact that there is no selection taking into account the situation of each unit at a given time or its optimal use (unavailability, history of requests). More specifically, existing systems assume that the energy storage and release units they control are all available and can be controlled at the same time.

However, if one of the available units has been disconnected, for example the unit US5 in the case illustrated in FIG. 3 (b), it can be seen that the control of the remaining energy storage and restitution units USi to US4 is insufficient to meet profile P. A result identical to that of FIG. 3 (b) would be obtained if the energy storage and restitution unit US5 is at least partially used in a context other than the frequency adjustment at when it is requested.

Thus, the known system therefore excludes a priori the use of storage units such as batteries for electric vehicles, which are brought to be frequently disconnected from the network to be used in vehicles, or uninterruptible power supplies (commonly called inverters by abuse of language) which could be used for other uses.

In addition, the previous principle is based on the constant use of all energy storage and release units under control. As a result, these energy storage and restitution units will have to take all the possible set values and frequently operate charge and discharge cycles, which can lead to their premature wear.

Solutions have already been envisaged to avoid using the storage batteries of a frequency regulation system of an electrical network too often. Thus, the document US 9,660,442 describes a system for regulating the frequency of a network, which associates at least one electric battery and an electric charge (such as an electric heater, a refrigerator, an air conditioner, an electric pump ...) located in consumers' homes, and which only uses the electric battery if the use of the electric charge is insufficient to meet the needs of frequency regulation.

To date, it is impossible to use, as part of frequency regulation, a wide variety of energy storage and restitution units owned by independent users, since some have too much power. low, that some are regularly unavailable for operational reasons, that a large part of them cannot take all the set values (and work in all or nothing) and / or that most are subject to technical constraints which are often incompatible with the very strict specifications imposed to be able to participate in frequency adjustment.

The object of the present invention is to propose a frequency regulation method and system which can take maximum advantage of a large number of energy storage and restitution units, despite their diversity in terms of constraints. technical or operational.

This object is achieved according to the invention which relates to a method of regulating a frequency of a network for the transport and / or distribution of electrical energy from a predefined group comprising a plurality of storage units and of restitution of electrical energy, able to be controlled individually, when they are connected to the transmission and / or distribution network, for injecting or withdrawing electrical energy on the transportation and / or distribution network. electrical energy, the process comprising:

a preliminary step of determining a first set of data relating to technical specifications associated with each energy storage and restitution unit, a second set of data relating to a current state associated with each storage unit and energy restitution, and a third set of data relating to usage preferences associated with at least one energy storage and restitution unit of said group;

a step of selection, among the energy storage and restitution units of said group, of energy storage and restitution units capable of being each controlled according to a specific individual contribution in injection or withdrawal, so as to that a sum of specific individual contributions in injection or withdrawal corresponds to a global setpoint, said selection being made as a function of data included in the first, second and third sets of data; and

- the simultaneous control of the energy storage and restitution units selected so that each operates in discharge, respectively in charge, according to its specific individual contribution in injection, respectively in withdrawal.

In addition to the main characteristics which have just been mentioned in the preceding paragraph, the method according to the invention may have one or more complementary characteristics among the following:

the selection step may include a step of calculating possible individual contributions for injection or withdrawal, capable of being brought by each energy storage and restitution unit of said group according to the data included at least in the first and the second set of data, and the specific individual contribution in injection or withdrawal for each energy storage and restitution unit is selected from the possible individual contributions;

- The method also preferably includes a step of preserving a history comprising a chronology relating to the selection of each storage and restitution unit within the framework of frequency regulation;

- the history may also include a chronology of the data from the second set of data;

- said selection can also be made according to the history;

the data of the first set preferably includes the possible charge / discharge power (s) and the storage / return capacity of the corresponding energy storage and return unit;

the data of the first set may further comprise a range of operating temperatures of the corresponding energy storage and restitution unit;

the data of the first set can further comprise at least one nominal operating power associated with the corresponding energy storage and restitution unit, and at least one energy storage and restitution unit is associated with a preference of use for which its specific individual contribution in injection or withdrawal when selected corresponds to said at least one nominal operating power;

the data of the first set can also include the possible operating mode or modes in terms of power, associated with the corresponding energy storage and restitution unit;

the data of the second set may include a current charge level and a current power injected or drawn off for the corresponding energy storage and restitution unit;

the data of the second set can further comprise a current temperature and / or a current voltage of the corresponding energy storage and restitution unit and / or a current state of a data communication link of the unit storage and return of corresponding energy and a remote control unit, and / or an alert signal;

the data of the third set may include preferred limitations in the possibilities of selecting the corresponding energy storage and restitution unit, comprising one or more time slots, and / or a maximum number of times the storage unit and corresponding energy return can be selected, and / or a maximum percentage of the energy storage and return capacity available if the corresponding energy storage and return unit is selected;

the preferred limitations preferably relate to a current state of charge of the corresponding energy storage and return unit with respect to a predefined threshold value, and / or to current use of the storage unit and return of corresponding energy in a context other than frequency regulation and / or at a current temperature, and / or at a current voltage of the corresponding energy storage and return unit, and / or at a current state a data communication link of the corresponding energy storage and restitution unit and a remote control unit, and / or to an alert signal;

- the preferences for using said third set of data can advantageously be each associated with a priority coefficient, and said selection is also carried out as a function of the priority coefficients.

The invention also relates to a system for regulating a frequency of a transport and / or distribution network of electrical energy from a predefined group comprising a plurality of storage and restitution units. energy, capable of being individually controlled, when they are connected to the network, for injecting or extracting electrical energy from the electrical energy transport and / or distribution network, the system comprising a control unit capable of communicating with each of the energy storage and restitution units of said group, and to be carried out:

a preliminary step of determining a first set of data relating to technical specifications associated with each energy storage and restitution unit, a second set of data relating to a current state associated with each storage unit and energy restitution, and a third set of data relating to usage preferences associated with the energy storage and restitution unit;

a step of selection, among the energy storage and restitution units of said group, of energy storage and restitution units capable of being each controlled according to a specific individual contribution in injection or withdrawal, so as to that a sum of specific individual contributions in injection or withdrawal corresponds to a global setpoint, said selection being made as a function of data included in the first set, in the second set and in the third set of data; and

- the simultaneous control of the energy storage and restitution units selected so that each operates in discharge, respectively in charge, according to its specific individual contribution in injection, respectively in withdrawal.

The energy storage and restitution units of said group can be located on one or more geographic sites, and the control unit is a centralized platform remote from said one or more sites.

The invention will be better understood on reading the description which follows, made with reference to the appended figures, in which:

- Figure 1, already described above, gives an example of a temporal variation of a frequency of a network for transport and / or distribution of electrical energy and a resulting setpoint to obtain regulation of this frequency;

- Figure 2, already described above, gives an example of a setpoint profile for frequency regulation;

FIG. 3, already described above, illustrates examples of control of a group of five energy storage and restitution units within the framework of a frequency regulation method of the prior art;

- Figure 4 schematically shows an example of architecture of a system for regulating the frequency of a network for transport and / or distribution of electrical energy according to the invention;

- Figure 5 gives an example of a usage profile of an energy storage and release unit;

FIG. 6 illustrates several possibilities for controlling energy storage and restitution units made possible according to different implementations of the invention to meet the setpoint profile of FIG. 2.

An example of a frequency regulation system for an electricity transmission and / or distribution network 1 (hereinafter electrical network 1), using a predefined group or fleet of electrical energy storage and restitution units according to the invention, is shown diagrammatically in FIG. 4.

In this example, we consider, for simplicity, that the system is based on the use of a group or park made up of six energy storage and restitution units denoted USi to US6, connected to the electrical network 1 and a control unit 2 for this set.

In the rest of the presentation, we will first briefly describe the nature and role of the various elements of the system (paragraph A below), then the general functioning of the system (paragraph B below). Finally, nonlimiting examples of system behaviors will be explained (paragraph C below).

A. Nature and role of the elements of the system

A.1 Electric energy storage and restitution units

The energy storage and restitution units USi to US6 can be any device or system making it possible to store and restore electrical energy. It can notably be a household rechargeable battery, an inverter, a battery for an electric vehicle, etc. An energy storage and return unit can possibly be composed of several sub-units.

The units USi to US6 can be different or identical. They can also be connected to the electrical network 1 permanently, temporarily, or intermittently.

The units USi to US6 can be owned by separate users. Thus, in the nonlimiting example of FIG. 4, the units USi and US2 are located on the same site Si, the units US3 and US4 are located on the same site S2, the unit US5 is located on a third site S3 , and the unit US6 is located on a fourth site S4. A site If at S4 can correspond indifferently to the home of a particular consumer, to the offices of a company, to rooms of a hotel ...

Some of the sites are also illustrated with electrical charges connected to the electrical network 1. Thus, electrical equipment E1 is available in site Si, and electrical equipment E2 is available in site S2. Electrical equipment or charge corresponds to any equipment capable of extracting a certain electrical power from the electrical network 1 when it is connected to it. It can in particular be a domestic appliance such as an electric radiator, a pump, a refrigerator, an air conditioner. The presence / absence of this electrical equipment is nevertheless without influence on the principle of frequency regulation according to the invention as will appear in the following description.

Each of the electrical energy storage and restitution units USi to US ₆ is further able to exchange data with an electronic data communication module 20 provided in the control unit 2. Each communication can be carried out with a connection wired or wireless. In the case where an electrical energy storage and restitution unit integrates a communication module suitable for the exchange of data with the module 20 (case of the units US4 and US6 in FIG. 4), the exchange of data is direct. Otherwise, an intermediate communication device is used. In the example of FIG. 4, an intermediate device Ucomi is used on the site Si to allow the exchange of data between on the one hand, the two units USi and US2, and on the other hand, the communication module 20 , an intermediate device Ucom3 is used on the site S2 to allow the exchange of data between the unit US3 and the communication communication module 20, and an intermediate device Ucoms is used on the site S3 to allow the exchange of data between the unit US5 and the communication module 20 for communication.

A.2 Control unit

In addition to the electronic communication module 20, the control unit 2 includes a calculator module 21, a memory 22 and a database

23. The control unit 2 is for example a centralized platform, hosted for example on the Internet.

Control unit 2 is responsible for processing in real time the data at its disposal (detailed below in paragraph B) to determine the group's energy storage and restitution units that will be called upon to respond to a setpoint. overall P corresponding to the power to be injected into the electrical network 1 or to be drawn from the electrical network 1 as part of the frequency adjustment. In one possible embodiment, the computer module 21 calculates the global setpoint P by itself from frequency measurements of the electrical network 1. As a variant, the computer module 21 can directly dispose of the power to be injected or drawn off to adjust the network frequency, without having to calculate it.

The selection will be based on the calculation of possible individual contributions in injection or withdrawal, able to be brought by each energy storage and restitution unit of said group according to certain data available, as will be explained later.

At the end of this calculation, the calculator module 21 may have determined several possible sets of energy storage and restitution units capable of being selected to respond to the global setpoint, and / or several ways of using storage units of an assembly to meet the global setpoint (in particular in the case where one or more energy storage and restitution units are capable of bringing several possible individual contributions).

The computer module 21 is then configured to select, from the group consisting of energy storage and restitution units USi to US6, units able to be individually controlled to inject or extract electrical energy from the network in real time. transport and / or distribution of electrical energy, so that the sum of individual contributions in injection or withdrawal of the selected units corresponds to the global setpoint P, the selection being made according to specific data which will also be detailed thereafter.

The selection covers both the identification of the energy storage and restitution units that will actually be used to meet the global setpoint, but also the selection, if one or more of the eligible storage units are capable of bringing several individual contributions possible by injection or withdrawal, from a specific compatible individual contribution.

In other words, the computer module 21 is capable of making the selection, among the energy storage and restitution units of the group, and according to the particular data, of energy storage and restitution units capable of each be controlled according to a specific individual contribution in injection or withdrawal selected from the possible individual contributions, so that a sum of specific individual contributions in injection or withdrawal corresponds to the global setpoint.

The control unit 2 then controls the simultaneous control of the energy storage and restitution units selected so that each operates in discharge, respectively in charge, according to its specific individual contribution in injection, respectively in withdrawal.

The control unit 2 also controls the storage, in the database 23, of certain data associated with each storage unit, such as for example a history making it possible to find in particular a chronology of the stresses of each storage unit in the context frequency regulation or any other framework.

B. General functioning of the system

Unlike known systems, the particular selection of energy storage and restitution units as a whole is based on taking into account specific data which can be classified into three categories or sets:

- a first set of data relating to technical specifications associated with each electrical energy storage and restitution unit in the group,

- a second set of data relating to a current state associated with each energy storage and restitution unit of the group, and

- a third set of data relating to usage preferences associated with at least one of the group's energy storage and restitution units.

Non-limiting examples of data are detailed below:

As mentioned above, the first set includes data relating to technical specifications associated with each electrical energy storage and release unit in the group.

The technical specifications, which are for example manufacturer data, include the possible charge / discharge power (s) and the storage / return capacity of the corresponding energy storage and return unit.

The data in the first set may further include the minimum or maximum charge and discharge times, and / or a range of operating temperatures of the corresponding energy storage and release unit.

The data in the first set can also include the possible operating mode or modes in terms of power associated with the corresponding energy storage and release unit, or the operating modes recommended by the manufacturer to maintain its warranty. Indeed, some of the storage and restitution units present in the group can have one or more fixed charge / discharge powers, while others can charge / discharge at variable powers. For example, an energy storage and restitution unit can be configured to load / unload exclusively at a power equal to 1 kilo watt, or exclusively at three powers equal respectively to 0.3 kilo watt, 0, 5 kilo watt and 1 kilo watt. Alternatively, an energy storage and release unit can be configured to charge / discharge at a power varying between 0.5 kilo watt and 1 kilo watt.

The data of the first set may further comprise at least one nominal operating power associated with the corresponding energy storage and release unit. As will be seen later in certain examples of selection strategies or criteria, this data can be used advantageously in the selection process by indicating for example that a unit for storing and restoring energy cannot be selected in the group for frequency regulation purposes only if it is possible to control it so that its specific individual contribution in injection or withdrawal corresponds to the nominal operating power. This guarantees that the unit is used in optimal operating conditions, reducing the risk of premature wear.

Other technical specifications can be taken into account. For example, the energy storage and restitution units can take different times to start up.

The data of the first set can be transmitted by any means by the manufacturers or the owners of each storage unit or can be determined after a technical analysis. These data are recorded in the database 23 so that the calculator module 21 can have access to them at any time, in particular when it has to calculate the possible individual contributions.

The second set includes data relating to a current state associated with each energy storage and restitution unit in the group.

For example, the data of the second set includes a current charge level and a current power injected or withdrawn for the corresponding energy storage and release unit.

By knowing a current power injected or withdrawn, it thus becomes possible to use simultaneously, for the frequency adjustment service, one or more energy storage and restitution units which until now were not integrated in such a service due to their use in a context other than frequency adjustment. The use of one or more energy storage and return units in another framework (self-consumption, long charge of electric vehicles, energy optimization, etc.) than that of frequency adjustment is then taken into account by l 'control unit.

Figure 5 illustrates an example of the current injection power profile of a production unit with a maximum charge / discharge power P _max of 1000 watts, which is injecting on the network at a power P _in j equal to 250 or 500 watts, for a use other than that of frequency adjustment. When the current injection power P _in j is 500 watts, it is also possible to use, as part of the frequency adjustment, a power Pdisp-inj available for injection equal to 500 watts, and a power Pdisp -all available for racking equal to 1500 watts.

The control unit 2 can preferably interrupt, anticipate, delay, modify the use made of the storage unit outside the frequency adjustment frame.

The data of the second set may further include a current temperature and / or a current voltage of the corresponding energy storage and restitution unit, or more generally any information, such as an alert signal, making it possible to identify a current state of the storage unit that is less favorable for stress on the unit in the context of frequency regulation.

Alternatively or in combination, the data of the second set may include a current state of a data communication link of the corresponding energy storage and release unit and a remote control unit.

The control unit 2 is thus able to constantly monitor the material state of the storage units and to adapt its selection strategy accordingly. In particular, it is capable of:

- spare certain energy storage and restitution units showing signs of failure or premature wear or in a non-optimal current state to be used, and / or

- change the setting of certain energy storage and release units, and / or

- communicate this information, in real time or deferred, to the operator of the energy storage and restitution units.

For example, if an energy storage and restitution unit fails, control unit 2 can stop it and / or alert its operator.

For example, if an energy return storage unit has too high a temperature, the control unit can temporarily stop it and / or alert its operator.

For example, if an energy return storage unit exhibits high or premature wear, the control unit can reduce or stop requesting this unit as part of the frequency adjustment and / or alert its operator.

The data of the second set can be transmitted, in an aggregated or individual manner, to the control unit 2, via the wired and / or wireless connections, by the storage and rendering units, or can be determined at the end of 'a technical analysis. These data are recorded in the memory 22 of the control unit 2 and can be modified in real time. This data is also advantageously kept in the history associated with each energy storage and restitution unit in the database 23.

Finally, the third set includes at least one item of data relating to usage preferences associated with at least one unit for storing and returning energy from the group.

Usage preferences can be given by different parties, for example an operator holding an energy storage and restitution unit, and / or by an operator not holding an energy storage and restitution unit , and / or by the supplier of the frequency regulation service, whether or not the latter owns all or part of the energy storage and restitution units. In the latter case, at least one, or even all the storage units in the group may be assigned common preference rules by the supplier of the frequency regulation service. These preference rules are for example stored at the level of the calculator module 21 or in the database 23. The preferences originating from the operators holding a storage unit can be transmitted by any means by the latter. These data are recorded in the database 23 so that the computer module 21 can access them at any time.

The usage preferences can include information relating to the use which can be made of the energy storage and / or restitution unit within the framework of the frequency adjustment or within a framework other than the frequency adjustment ( for example self-consumption, supply security, electric vehicles, etc.).

As a variant or in combination, the usage preferences may correspond to desired limitations in the possibilities of selecting one or more energy storage and restitution units.

These limitations include for example one or more time slots, and / or a maximum number of times the corresponding energy storage and release unit can be selected per day, and / or a maximum percentage of the storage capacity and energy return available if the corresponding energy storage and return unit is selected, and / or minimum or maximum durations preferably limited in charge or in discharge.

For example, the operator of an energy storage and release unit may wish to allocate 10% of the available energy storage and release capacity to the frequency setting.

According to another non-limiting example, the operator may wish to allocate 10% of the energy storage and restitution capacity available at the frequency setting between 07:00 and 23:00 and 50% between 23:00 and 07:00.

The operator can also request that his energy storage and restitution unit is not used more than once a day as part of the frequency adjustment.

Other limitations may relate to a current charge level of the corresponding energy storage and return unit with respect to a predefined minimum or maximum threshold value, and / or to current use of the storage unit. and corresponding energy restitution in a context other than frequency regulation.

For example, the operator can request that its energy storage and restitution unit is not used as part of the frequency adjustment if the unit's current charge level is less than 50%.

The operator can also exceptionally prohibit the use of its energy storage and release unit for the next six hours.

As mentioned above, another preference for use may consist in indicating that at least one of the group's storage and restitution units can only be selected insofar as its specific individual contribution corresponds to a nominal power of operation of this unit.

Preferences for use can advantageously be combined with a priority coefficient. A maximum priority coefficient can mean that a usage preference is imposed (and thus becomes a constraint). Thus, some preferences may be imperative, while others may tolerate exceptions (for example: do not use the batteries between 6:00 p.m. and 8:00 p.m. except exceptionally (for example if risk of black ouf), use the batteries within the limit of three times a day).

From these three sets of data, the calculator module 21 will be able to select the storage and / or energy units that will be called upon to respond to a global setpoint in the context of frequency regulation.

More precisely, from the data collected in the first set and the second set, the calculator module 21 is able to determine what it is technically possible to do to respond to the global setpoint. In particular, the calculator module 21 can implement a step of calculating possible individual contributions in injection or withdrawal, capable of being brought by each unit USi to US6 of energy storage and restitution of the group according to the data included at least. in the first and second datasets.

As indicated above, at the end of this calculation, the computer module 21 may have several possible solutions for effectively responding to the global setpoint, for example several possible sets of energy storage and restitution units capable of being selected to respond to the global setpoint, and / or several ways of using storage units of a set to meet the global setpoint.

By using the preferences or rules of use contained in the third set of data, the calculator module 21 will be able to determine the or one of the best solutions by selecting the energy storage and restitution units of the group whose sum of specific individual contributions in injection or withdrawal (each specific individual contribution being selected from the possible individual contributions) will make it possible to correspond to the global instruction for the frequency adjustment while satisfying at best the preferences of use.

Certain usage preferences may require that the calculator module 21 consult the history giving in particular a chronology of the stresses of each storage unit in the context of frequency regulation. This is the case, for example, if the usage preference is relative to the fact that one or more energy storage and restitution units should not be requested for energy control if they have been recently requested.

A selection strategy could consist in making the most of the usage preferences given by the third set of data.

When the usage preferences are accompanied by a priority coefficient, a selection strategy could for example consist in using the usage preferences as much as possible according to their priority coefficient.

Thereafter, the control unit 2 transmits, via the electronic communication module 20, orders to the energy storage and restitution units which have been selected so that they modify their injected / withdrawn powers according to their respective specific individual contribution.

These orders can be transmitted, in real time or in advance.

C. Examples of how the system works

Given the taking into account of data coming from the three aforementioned sets, there are a large number of possibilities allowing the control unit 2 to determine, in real time, the charge or discharge orders to be transmitted to the control units. energy storage and restitution in order to be able to obtain the power required as part of the frequency adjustment, while respecting the operating preferences of all energy storage and restitution units (participation in the self-consumption of a site racking, power reserve, optimization of the operating cycle in order to improve the service life of the unit, etc.).

For example, the computer module 21 can, in order to follow a power injection instruction while optimizing the state of charge of its fleet, choose a solution favoring the discharges of the most charged energy storage and restitution units rather than a solution discharging partially discharged units. Conversely, the computer module 21 can, in the event that it has to follow a withdrawal instruction, favor a solution loading as a priority the discharged storage units.

In another example, when the calculator module 21 has, via the history, the information that an energy storage and restitution unit has already been requested during the day (whether for frequency adjustment or for personal use of the operator) while other units have not been requested, he may adopt a selection strategy calling in priority on units that have not already been requested during the day (in order to follow a request for the operator or to optimize the service life of the units).

In another example, the computer module 21 has access to several subgroups of storage units. One of these subgroups contains units to be used only as a last resort. The calculator module can then adopt a selection strategy which makes it possible not to request these units or which minimizes the requests on these units.

Table 1 below illustrates an example of a possible selection strategy for achieving a 2000 Watts injection target from a fleet comprising four batteries (numbered from 1 to 4 in the first column of the table), depending on the level charge of these batteries (data from the second set, in the second column of Table 1), usage preferences (data from the third set, in the third column of Table 1), the number of recent requests made for each battery (data from the history, in the fourth column of table 1). In this example, the four batteries have a nominal power of 1000 Watts in charge or discharge (data from the first set).

Table 1: Global injection setpoint = 2000 Watts Drums Charge preferences History (number of recent requests) Possible strategies 1 2 3 4 NOT 1 80% Any 0 1000 0 0 1000 500 2 80% Any 0 1000 1000 0 0 500 3 80% Any 0 0 1000 1000 0 500 4 80% Use of last resort 0 0 0 1000 1000 500

All batteries present at the same current level of charge (80%). History shows that no battery has recently been used as part of charge regulation. Only battery 4 is associated with a usage preference indicating that this battery should only be used as a last resort. This preference for use can come from a wish of the operator, or can be determined from the technical characteristics of the battery (we can for example consider that lead acid technology batteries are only to be used as a last resort because it supports less charge and discharge cycles), or of its current state (close to a state of complete discharge for example). The calculator module 21 determines several possible strategies making it possible to respond to the set point of 2000 Watts. Only five possible strategies are illustrated in the last five columns of Table 1:

- strategy 1 selects the battery 1 and 2 sure their power nominal 1000 Watts; - strategy 2 selects the battery 2 and 3 sure their power nominal 1000 Watts; - strategy 3 selects the battery 3 and 4 sure their power

nominal 1000 Watts;

- strategy 4 selects batteries 1 and 4 at their nominal power of 1000 Watts;

- strategy N selects all batteries on 500 Watts.

From the information (technical characteristics, history, usage preferences, etc.) available, the calculator module 21 will choose the most suitable solution (from solutions 1 or 2 if we limit ourselves to the information and examples cited).

Table 2 below illustrates another example of a possible selection strategy for achieving a 4000 Watts injection target from a fleet comprising six batteries (numbered from 1 to 6 in the first column of Table 2), depending the charge level of these batteries (data from the second set, in the second column of Table 2), usage preferences (data from the third set, in the third column of Table 2), the number of requests recently made for each battery (data from history, in the fourth column of Table 2). In this example, the six batteries have a nominal power of 1000 Watts in charge or discharge (data from the first set). Battery 4 should only be used as a last resort. Batteries 5 and 6 are batteries that should not be called more than once a day. The batteries having already been used once during the day. Unlike the example in Table 1, there is no strategy to meet all the constraints but the calculator module can choose a preferable strategy compared to the others. We could for example consider that strategy 2 which requests a second time a battery having already been requested during the day will be preferable to strategy 1 which requests a battery which should only be used as a last resort. The ability to make a choice is only made possible by collecting data from the first, second and third data sets. Thus, the invention makes it possible to take such preference parameters into account, and allows the service provider of the frequency regulation service to implement them.

Table 2: Global injection setpoint = 4000 Watts Drums Charge preferences History (number of recent requests) Possible strategies 1 2 3 4 NOT 1 80% Any 0 1000 1000 0 1000 1000 2 80% Any 0 1000 1000 0 1000 0 3 80% Any 0 1000 1000 1000 1000 1000 4 80% Use of last resort 0 1000 0 1000 0 1000 5 60% Avoid more than one request per day 1 0 1000 1000 0 1000 6 60% Avoid more than one request per day 1 0 0 1000 1000 0

Figure 6 illustrates, without being exhaustive, other possibilities:

For the sake of simplification, the different situations (a) to (e) shown diagrammatically in FIG. 6 all correspond to ways of managing the six energy storage and restitution units USi to US6 of the system presented by way of example on FIG. 4, to respond to the profile setpoint P of FIG. 2. Each situation illustrates the specific individual contributions in electricity injection. As in the case of FIG. 3, the horizontal axis 10 representative of time here represents four identical periods, each corresponding to a sampling period of the reference signal, which can vary from the second to a few minutes. All situations (a) to (e) show that the system makes it possible to obtain compliance with the instruction in all cases, unlike the methods of the prior art.

The situation (a) of FIG. 6 corresponds to the particular nonlimiting case where all the units USi to US6 are identical and capable of operating at different injection powers (discharge powers). It is also assumed that the unit US5 is not available for selection here, the knowledge of this unavailability, for whatever reason, resulting from the analysis of the data associated with this unit in the first, second and / or third dataset. It will be recalled that a system according to the prior art, like the situation described above with reference to FIG. 3 (b), would have requested for each period the six units in equal proportion, and would therefore not have could not reach the setpoint since the US5 unit is actually unavailable. Thanks to the system according to the invention, the computer module 21 is capable of selecting only the units USi, US2, US3, US4 and US6, and only these selected units are controlled to inject into the network a power equal to 200 watts during the first period, 600 watts during the second period, 400 watts during the third period, and again 200 watts during the fourth period.

Situation (b) of FIG. 6 corresponds to the particular nonlimiting case where all the units USi to US6 are identical, capable of operating at different injection powers (discharge powers), but have a nominal operating power equal to 1000 watts. This nominal operating power data is in this example a technical specification included in the first set. It is assumed that the units USi to US5 are in a current state allowing them effectively to inject their nominal operating power. It is also assumed that the unit US ₆ is not available for selection here, the knowledge of this unavailability, for whatever reason, resulting from the analysis of the data associated with this unit in the first, second and / or third data sets. Here, we apply the previously stated preference rule according to which an energy storage and restitution unit should only be selected if its individual contribution in injection or withdrawal corresponds to its nominal operating power. With the previous hypotheses, the selection here relates only to the units USi to US5. It can be seen in Figure 6 (b) that:

- during the first period, only the USi unit is controlled to inject into the network at its nominal power of 1 kilo watts;

- during the second period, it is the units US2, US3 and US4 which are controlled to inject into the network at their nominal power of 1 kilo watts;

- during the third period, it is the units US2 and US3 which are controlled to inject into the network at their nominal power of 1 kilo watts;

- during the fourth period, only the US5 unit is controlled to inject on the network at its nominal power of 1 kilo watts.

As indicated previously, the fact of operating the units only at their nominal operating power makes it possible to preserve the life of these units.

In addition, it can also be seen in FIG. 6 (b) that the setpoint variation from one period to another is treated by a rotation of the units requested. In other words, although available, the units USi to US5 are not used every period, so here again the risk of premature wear is reduced.

Figure 6 (c) corresponds to the specific non-limiting case where the energy storage and restitution units do not have the same nominal operating powers. It is assumed that USi, US3, US4, US5 and US6 have a nominal operating power equal to 1000 watts and that US2 has a nominal operating power equal to 2000 watts. It is also assumed that the US5 and US6 units are not available for selection, for whatever reason.

It follows from Figure 6 (c) that:

- during the first period, only the USi unit is controlled to inject on the network at its nominal power of 1 kilo watt;

- during the second period, it is the units USi and US2 which are controlled to inject into the network at their nominal power of 1 kilo watts and 2 kilo watts respectively;

- during the third period, only the US2 unit is controlled to inject into the network at its nominal power of 2 kilo watts;

- during the fourth period, only the US4 unit is controlled to inject on the network at its nominal power of 1 kilo watts.

We also note that, although available for selection, the US unit does not need to be used.

The situation (d) in figure 6 is similar to the situation in figure 6 (b) (all the units USi to US6 are identical, capable of operating at different injection powers with a nominal operating power equal to 1000 Watts , and the unit US6 is not available), except that the principle according to which an energy storage and restitution unit can only be selected if its individual contribution available for injection or withdrawal corresponds to its power nominal operation is applied here only to the unit USi. It follows from Figure 6 (d) that:

- during the first period, only the USi unit is controlled to inject into the network at its nominal power of 1 kilo watts;

- during the second period and the third period, the USi unit is controlled to inject on the network at its nominal power of 1 kilo watts, and the USi to US4 units are controlled equally but with a power varying between the second and the third period;

- during the fourth period, only the USi unit is controlled to inject into the network at its nominal power of 1 kilo watts.

In the situation (e) of figure 6, the units USi to US6 can only be used at their nominal operating power in charge or in discharge, equal to 1 kilo watts. The US6 unit is not available for selection here, for whatever reason. Finally, the units of USi, US2 and US3 must, in this nonlimiting example, be used for a minimum operating time corresponding to four periods. This last constraint is in particular in the third set of data. In this situation we see in particular that:

- the units USi, US2 and US3 are controlled over the second, third and fourth periods to inject into the network at their nominal power of 1 kilo watts, this in order to respect their constraint in minimum operating time;

- that it is therefore necessary, to comply with the profile P instruction, to check:

the US4 unit to draw from the network at its nominal power of 1 kilo watts over the third period;

geese two units US4 and US5 to draw from the network at their nominal power of 1 kilo watts in the fourth period.

The invention makes it possible to meet the requirements of frequency adjustment while using electrical energy storage and restitution units with varied operating constraints and a priori incompatible with the specifications imposed by the managers of the transport network and / or electricity distribution.

The invention makes it possible to make use of, as part of the frequency adjustment, storage capacities comprising more severe usage constraints, and therefore at lower purchase cost.

In certain implementations proposed by the invention, the intelligence of the aggregation makes it possible to preserve the life of the energy storage and restitution units used in the context of frequency adjustment:

- essentially soliciting them in their nominal schemes,

- by reducing the number of charges and discharges per unit,

- by reducing the duration of the loading and unloading moments of the units,

- by reducing the frequency of charging or discharging storage units.

In certain proposed implementations, the invention further proposes to take into account one or more uses (other than frequency regulation) capable of being attributed to a storage and / or energy restitution unit. It thus becomes possible to accept that the same unit can be used simultaneously for frequency adjustment and for another use, provided that all the constraints assigned to this unit are respected.

The invention makes it possible to manage the planned or fortuitous unavailability of a part of the energy storage and restitution units and to ensure the adjustment commitment, despite the incidents.

By aggregating the storage units, the invention makes it possible to generate economies of scale by pooling operating costs.

Claims (16)

REVENDI CATI ONS 1. Method for regulating a frequency of a network (1) for transporting and / or distributing electrical energy from a predefined group comprising a plurality of storage and restitution units (USi to US6) of electrical energy, capable of being individually controlled, when they are connected to the transport and / or distribution network (1), for injecting or withdrawing electrical energy onto the transport and / or distribution network electrical energy, the process comprising: a preliminary step of determining a first set of data relating to technical specifications associated with each energy storage and restitution unit, a second set of data relating to a current state associated with each storage unit and energy restitution, and a third set of data relating to usage preferences associated with at least one energy storage and restitution unit of said group; a step of selection, among the units (USi to US6) of energy storage and restitution of said group, of energy storage and restitution units capable of being each controlled according to a specific individual contribution by injection or by racking, so that a sum of specific individual contributions in injection or racking corresponds to a global setpoint, said selection being made according to data included in the first, second and third sets of data; and - the simultaneous control of the energy storage and restitution units selected so that each operates in discharge, respectively in charge, according to its specific individual contribution in injection, respectively in withdrawal. 2. Method according to claim 1, characterized in that the selection step comprises a step of calculating possible individual contributions in injection or withdrawal, able to be brought by each unit (USi to US ₆ ) for storage and restitution energy of said group as a function of the data included at least in the first and second sets of data, and in that the specific individual contribution in injection or withdrawal for each unit (USi to US6) of storage and restitution of energy is selected from the possible individual contributions. 3. Method according to any one of the preceding claims, characterized in that it further comprises a step of preserving a history comprising a chronology relating to the selection of each storage and restitution unit within the framework of regulation. frequency. 4. Method according to claim 3, characterized in that the history also includes a chronology of the data of the second set of data. 5. Method according to any one of claims 3 or 4, characterized in that said selection is also carried out according to the history. 6. Method according to any one of the preceding claims, characterized in that the data of the first set include the possible charge / discharge power (s) and the storage / restitution capacity of the storage and restitution unit. corresponding energy. 7. Method according to claim 6, characterized in that the data of the first set further comprises a range of operating temperatures of the corresponding energy storage and return unit. 8. Method according to any one of claims 6 or 7, characterized in that the data of the first set further comprises at least one nominal operating power associated with the corresponding energy storage and release unit, and in that at least one energy storage and restitution unit is associated with a usage preference for which its specific individual contribution in injection or withdrawal when selected corresponds to said at least one nominal operating power. 9. Method according to any one of claims 6 to 8, characterized in that the data of the first set further comprises the possible operating mode or modes in terms of power, associated with the storage and restitution unit. corresponding energy. 10. Method according to any one of the preceding claims, characterized in that the data of the second set include a current charge level and a current power injected or withdrawn for the corresponding energy storage and restitution unit. 11. The method of claim 10, characterized in that the data of the second set further comprises a current temperature and / or a current voltage of the corresponding energy storage and restitution unit and / or a current state of a data communication link of the corresponding energy storage and restitution unit and a remote control unit (2), and / or an alert signal. 12. Method according to any one of the preceding claims, characterized in that the data of the third set include preferred limitations in possibilities of selecting the corresponding energy storage and restitution unit, comprising one or more time slots, and / or a maximum number of times that the corresponding energy storage and release unit can be selected, and / or a maximum percentage of the available energy storage and release capacity if the storage unit and corresponding energy return is selected. 13. Method according to claim 12, characterized in that the preferred limitations relate to a current state of charge of the corresponding energy storage and restitution unit with respect to a predefined threshold value, and / or to use current of the corresponding energy storage and release unit in a context other than frequency regulation and / or at a current temperature, and / or at a current voltage of the energy storage and return unit corresponding, and / or to a current state of a data communication link of the corresponding energy storage and restitution unit and a remote control unit (2), and / or to an alert signal. 14. Method according to any one of the preceding claims, characterized in that the preferences for using said third set of data are each accompanied by a priority coefficient, and in that said selection is also carried out as a function of the coefficients priority. 15. System for regulating a frequency of a transport and / or distribution network of electrical energy from a predefined group comprising a plurality of units (USi to USe) for energy storage and restitution , capable of being individually controlled, when they are connected to the network, for injecting or withdrawing electrical energy from the electrical energy transport and / or distribution network, the system comprising a control unit (2) capable to communicate with each of the energy storage and restitution units of said group, and to perform: a preliminary step of determining a first set of data relating to technical specifications associated with each energy storage and restitution unit, a second set of data relating to a current state associated with each storage unit and energy restitution, and a third set of data relating to usage preferences associated with the energy storage and restitution unit; a step of selection, among the energy storage and restitution units of said group, of energy storage and restitution units capable of being each controlled according to a specific individual contribution in injection or withdrawal, so as to that a sum of specific individual contributions in injection or withdrawal corresponds to a global setpoint, said selection being made as a function of data included in the first set, in the second set and in the third set of data; and - the simultaneous control of the energy storage and restitution units selected so that each operates in discharge, respectively in charge, according to its specific individual contribution in injection, respectively in withdrawal. 16. System according to claim 15, characterized in that the energy storage and restitution units of said group are located on one or more geographic sites (Si to S4), and in that the control unit (2) is a centralized remote platform from said one or more sites.