Control of a hybrid power plant comprising an electrical production source and a storage system

Abstract

The present disclosure relates to a method for controlling a hybrid power plant (100) comprising an electrical production source (2) and an energy storage system (3), the method comprising determining a power setpoint to be supplied by the source and the storage system taking into account: - dynamics of the source; - a state of charge of the storage system; and - extreme values ​​that can be taken by an instantaneous control value of the source imposing a speed of variation of a power value of the source; and - control of the source and the storage system by the setpoints. Figure for the abstract: Fig. 1

Description

Title of the invention: Control of a hybrid power plant comprising an electrical production source and a storage system Technical field

[0001] This disclosure relates generally to the production of electrical energy and more particularly to the management systems of hybrid power plants. STATE OF THE ART

[0002] Thermal power plants of the combined gas cycle type are known. They are composed of a combustion turbine that can respond quickly to a demand for electricity and a steam turbine with slower dynamics. A power reserve can be associated with the power plant and the power plant is usually operated below this reserve. When the network manager wishes to request this reserve, it sends a signal to adjust the frequency of the electrical network. This signal is an image of the speed at which it wishes to move from an operating point corresponding to the sale of the energy to be produced by the production source itself to a second operating point corresponding to the sale of energy and to all or part of the reserve absorbed or transmitted.The manager asks the producers participating in the secondary frequency control to modulate their power around their production point linked to the sale of energy. This power modulation is done via a frequency control signal that the manager sends to the producers and that they multiply by the volume of reserve that they dedicate to the secondary control. This signal being between -1 and 1, the power plants will therefore have to modulate their power by decreasing it or increasing it to the maximum of the entire contracted reserve. If the frequency control signal is equal to 0, the set power does not differ from the production program linked to the sale of energy.

[0003] But the dynamics of an electrical production source include an "inertia" which does not always allow it to respect the power variation speed requirement imposed by the network manager. In such a case, the production source may be limited in its capacity to vary its power sufficiently quickly. Thus, this type of power plant is limited by the dynamics of the steam turbine which therefore does not allow it to follow the setpoint imposed by the manager.

[0004] To remedy this, the operating point linked to the sale of energy can be reduced to ensure the release of the reserve within the allotted time by creating margin on the combustion turbine. This principle is called "derating". But, in the In practice, this solution represents a disadvantage and a significant cost for the power plant. Indeed, the disadvantage of derating is that it amounts to permanently restricting the production linked to the sale of energy when the power plant participates in the secondary control. This is the case, for example, of a combined gas power plant with a maximum power of 500 MW, which can offer a reserve power volume of 100 MW maximum in 300 s. In other words, the maximum upward or downward slope that the power plant can follow is 20 MW / min. To provide the maximum reserve power volume for this secondary control, a derating of 20 MW is however necessary (this derating is determined by the delay of the steam turbine over 600 s). The power linked to the sale of energy has therefore decreased by 20 MW.Thus, assuming that this power plant operates 5000 hours per year, including 2000 hours in secondary frequency control, this derating represents a loss of production of the order of 40 GWh, or 1.7% of the annual production of the power plant. If we consider a variable cost margin of €10 / MWh, this represents a loss of €400,000 / year.

[0005] Energy storage means can also be associated with the electricity production system in order to compensate for the inertia of the electricity production source without limiting its operation. In the example of a 500 MW combined cycle gas power plant, battery storage with a power of 20 MW can supplement the slow dynamics of the steam turbine. This has the advantage of eliminating the 20 MW derating by increasing the reserve (110 MW instead of 100 MW) as well as the operating point linked to the sale of energy by 10 MW.Furthermore, the energy dimensioning of the battery can be optimized by simulating hybridization and activation for secondary frequency control. In our example, a battery with a capacity of 20 MWh is sufficient. However, if other services are to be planned, they may prove more limiting for the dimensioning of this battery.

[0006] A first control solution for this hybrid power plant consists of using a control device to guarantee the dynamics imposed by the network manager for monitoring the frequency adjustment signal. The device "clamps" the signal to make it correspond to the dynamics of the electricity production source and asks the storage system for the missing quantity of energy in order to respect the manager's instruction.

[0007] However, this solution is not sustainable. Indeed, over time, the state of charge of the energy storage system decreases to reach a zero value, thus compromising the possibility for the hybrid power plant to provide the service over time. GENERAL STATEMENT

[0008] An aim of the present disclosure is to improve the control of power plants hybrids.

[0009] To this end, a first aspect proposes a method for controlling a hybrid power plant,

[0010] the method comprising at least once the implementation of the following steps:

[0011] - considering a power setpoint of the power plant and an instantaneous value control panel current,

[0012] the current instantaneous control value of the power plant imposing a speed of variation of a power value of the power plant,

[0013] the setpoint and the current instantaneous value intended to compensate for a difference between a frequency of an electrical network and a nominal frequency of the network,

[0014] determination of an activation instruction for a reserve power of an electrical production source of the power plant from a measurement value of a state of charge of an energy storage system of the power plant and taking into account a minimum value and a maximum value which can be taken by a subsequent instantaneous control value of the power plant,

[0015] the reserve power of the source being a predetermined source power margin,

[0016] the minimum and maximum values ​​being a function of the current instantaneous control value of the central unit and of a predetermined threshold of speed of variation of the current instantaneous control value of the central unit,

[0017] the activation instruction being between a first terminal and a second terminal,

[0018] the first and second terminals being a function of a maximum power available in the storage system, of the reserve power of the power station, of the reserve power of the source, of the current instantaneous control value of the power station, of the minimum and maximum values ​​and of a threshold of speed of variation of power of the source;

[0019] - from the activation instruction of the reserve power of the source and a reserve power of the power plant, determination of a current instantaneous value of control of the source,

[0020] the current instantaneous control value of the source imposing a speed of variation of a power value of the source,

[0021] the reserve power being a predetermined power margin of the power plant;

[0022] - from a power setpoint excluding reserve of the source and the ins value current source control tantanate, determination of a power setpoint to be supplied by the source,

[0023] the non-reserve power of the source corresponding to the power supplied by the power station which does not contribute to the frequency adjustment;

[0024] - from a measurement of the power supplied by the source and the setpoint of power of the power plant, determination of a power setpoint to be supplied by the storage system by compensating for a difference between the power supplied by the source and the power setpoint of the power plant; and

[0025] - control of a power supplied by the source and of a power supplied by the storage system respectively from the power setpoint to be supplied by the source and the power setpoint to be supplied by the storage system.

[0026] Thus, such a control method makes it possible to comply with both the network manager's instructions and the dynamics of the electricity production source while maintaining the state of charge value at an acceptable level for the batteries.

[0027] It also has the advantage of retaining the previous configuration of the hybrid control unit control device by only modifying the instructions.

[0028] It may be provided that the method is implemented such that the first and second limits are determined respectively by the following expressions: ^Pr'jm'n ~ Pr~ ( 1 " N [ ) ' Pr~ Ps^nax ' C-Pr'jnax ~ “P > + (1 + 'Pr + Psmax' with Cpr'jnjn the first terminal and Cpr'ma!( the second terminal, Psjnax the maximum power available in the storage system, Pr the reserve power of the power station, Pr' the reserve power of the source, and Nj the current instantaneous value.

[0029] It may be provided that the method further comprises a calculation of a second activation setpoint of the reserve power of the source for the subsequent instantaneous value,

[0030] the method being implemented so that a slope value between a first point corresponding to the activation setpoint calculated for the current instantaneous value and the activation setpoint calculated for the subsequent instantaneous value is limited, for example by filtering, in order to respect the power variation speed threshold of the source.

[0031] It may also be provided that the method is implemented such that a minimum limit of the state of charge is worth a fraction, for example 40%, of a total capacity of the storage system and that a maximum limit of the state of charge is worth a fraction, for example 60%, of the total capacity of the storage system,

[0032] and so that the activation instruction of the reserve power of the source is equal, if the measurement value of the state of charge is strictly greater than the maximum limit, to the first terminal and, if the measurement value of the state of charge is strictly less than the minimum limit, to the second terminal.

[0033] The minimum limit and the maximum limit are state of charge values.

[0034] It may also be provided that the method is implemented so that the current instantaneous value aims to deliver the reserve power in less than 300 seconds, the current instantaneous value being between -1 and 1.

[0035] It may be provided that the method is implemented so that the current instantaneous value aims to deliver the reserve power of the power station in less than 30 seconds to compensate for the difference between a frequency of an electrical network and a nominal frequency of the network,

[0036] a value of the nominal frequency of the network being equal to 50.0 Hz and a value of the same deviation being equal to -200 millihertz,

[0037] the current instantaneous value being proportional to the same deviation.

[0038] It may further comprise a step of saturating the current instantaneous control value of the source.

[0039] According to a second aspect, a device for controlling a hybrid power plant is provided, the device being configured to implement a method according to the first aspect.

[0040] According to a third aspect, a computer program product is provided comprising instructions which, when the program is executed by a computer, cause the latter to implement a method according to the first aspect.

[0041] According to a fourth aspect, computer-readable storage means are provided, on which a computer program product according to the third aspect is recorded.

[0042] According to a fifth aspect, a hybrid power plant is provided comprising: - a device for controlling the hybrid power plant according to the second aspect; - a source of electrical production; and - an energy storage system, the production source and the storage system being configured to be controlled by the control device. DESCRIPTION OF FIGURES

[0043] Other characteristics, aims and advantages will emerge from the following description, which is purely illustrative and non-limiting, and which must be read in conjunction with the appended drawings in which:

[0044] [Fig.l] schematically illustrates an example of power plant architecture, detailing the inputs and outputs;

[0045] [Fig.2] is a flowchart illustrating a mode of implementation of a method for controlling a hybrid power plant;

[0046] [Fig.3] illustrates an example of a causal model for simulating a hybrid power plant control device;

[0047] [Fig.4] illustrates another example of a causal model for simulating a hybrid power plant control device;

[0048] [Fig.5] illustrates the causal model of [Fig.4] in a particular case,

[0049] [Fig.6] illustrates the causal model of [Fig.4] in another particular case,

[0050] [Fig.7] illustrates the causal model of [Fig.4] in a particular case different from the figures 5 and 6;

[0051] [Fig.8] illustrates a variant of the causal model of [Fig.4];

[0052] [Fig.9] illustrates a simulation result of the control device of [Fig.4] requested by an instruction imposed by the network manager in a first case; and

[0053] [Fig. 10] illustrates a simulation result of the same control device requested by an instruction imposed by the network manager in a second case. DETAILED DESCRIPTION

[0054] As an example, [Fig.l] shows a hybrid power plant 100 composed of an electrical production source 2 and an energy storage system 3, each power supplied P', Ps of which is controlled by a control device 1.

[0055] The source of electrical production 2 may for example be a combined cycle gas power plant comprising a combustion turbine and a steam turbine, a conventional gas, fuel oil or coal power plant, a nuclear power plant or a hydroelectric power plant.

[0056] The energy storage system 3 may be a set of batteries, or even a battery or any other storage means configured to supply an electrical network.

[0057] In this description, we consider the case where the hybrid power plant increases or decreases (also referred to as absorption) the power P that it supplies to the electricity network in order to regulate the network frequency. That is to say, the power supplied increases or decreases in order to compensate for a deviation from the network frequency previously set, for example at 50 Hz by the network manager in France or in Europe. The link between the power supplied by the plant and its ability to act on the network frequency is known and will not be detailed further.

[0058] However, it may be expected that the power plant must provide this power within a given time. A dynamic constraint may therefore be imposed on the power plant, in particular by the manager.

[0059] For example, in France, a central unit 100 participating in the secondary frequency adjustment is configured to deliver this power in less than 30 seconds in order to compensate for a frequency deviation of -200 mHz. In another example, this power is delivered in less than 300 seconds.

[0060] In order to respect the imposed dynamics, it is provided that the control device 1 implements a method whose implementation steps are illustrated by way of example in [Fig.2].

[0061] In the following, this presentation will be detailed for a power supplied by the power station to compensate for the difference and applies mutatis mutandis to the case where the difference is compensated by a power absorbed by the power station.

[0062] We consider a power setpoint CP of the power plant and a current instantaneous value Ni of control of the power plant.

[0063] The current instantaneous value Ni imposes a speed of variation of a power value of the power plant from a current operating power to the setpoint and aims to compensate, jointly with the setpoint, the aforementioned deviation. We can also speak of a gap.

[0064] Therefore, the CP instruction can be represented by the following equation:

[0065] Cp — Po + Ni' Pr

[0066] with:

[0067] Po representing a power outside the reserve of the source, and

[0068] Pr representing a reserve power of the power plant which are predetermined data completed.

[0069] The non-reserve power Po corresponds to a power supplied for a service other than the frequency control. For example, the non-reserve power corresponds to what the power station supplies to supply the network. This power therefore does not contribute to the frequency control.

[0070] The reserve power Pr of the power plant corresponds to a power margin provided for other services such as frequency control. It is therefore defined in particular as a margin between the non-reserve power and the nominal power corresponding to what the power plant is capable of providing at maximum power and therefore depends on the construction data of the power plant. In the present application, this definition may be applied to other reserve powers, in particular the reserve power Pr' of source 2.

[0071] We then understand that the dynamics followed by the central unit is imposed by the current instantaneous value Ni at each instant.

[0072] These values ​​also constitute over a period a signal, known as a “remote adjustment signal”, or even a “frequency adjustment signal”.

[0073] For example, in France, this signal is between -1 and 1. Over a given period, it can be divided into several linear sections with a negative or positive slope.

[0074] From then on, it is further understood that the power supplied or absorbed by the power plant to compensate for the frequency difference is defined by the product N; ■ Pr. Indeed, at each instant, the value Ni depends on the difference and its product with the value of the reserve power amounts to determining at this instant what proportion of the reserve power is to be supplied or absorbed to compensate for the difference.

[0075] Therefore, it is a question of setting up a control strategy for the power plant which aims to determine what are the power shares respectively of source 2 and of storage system 3. To determine these shares, account is taken of the dynamics imposed by the manager but also that imposed naturally by source 2, for example for the combined gas power plants mentioned above in this description which may have an inertia compromising the capacity of the power plant to follow the imposed dynamics.

[0076] It is also considered that the state of charge SOC (“State of charge”) of the energy storage system 3 is continuously measured so as to transmit this information to the control device 1. The state of charge SOC is characterized by a predetermined minimum limit SOCmin and a maximum limit SOCmax. These limits define limits within which the state of charge SOC must be located in order not to compromise over time the capacity of the hybrid power plant to provide the service.

[0077] The minimum limit SOCmin and the maximum limit SOCmax are parameters for maintaining the state of charge of the energy storage system 3.

[0078] Thus, according to one embodiment, the minimum limit SOCmin is equal to 40% of the total capacity of the energy storage system 3 and the maximum limit SOCmax is equal to 60% of this total capacity.

[0079] According to another embodiment, the minimum limit SOCmin can reach 20% of the total capacity and the maximum limit SOCmax can reach 80% of the total capacity.

[0080] During a step E1, the activation instruction for the reserve power of an electrical production source of the power plant is determined from a SOC value measuring a state of charge of the storage system of the power plant.

[0081] In developing this instruction, a minimum value and a maximum value which can be taken by a subsequent instantaneous value Ni+i for controlling the control unit are also taken into account.

[0082] These minimum and maximum values ​​are determined as a function of the current instantaneous value Ni of the control unit and a predetermined threshold of variation speed of this current instantaneous value. This threshold is for example determined in advance by the dynamics imposed by the manager which will have an influence on the slope of the remote control signal.

[0083] To do this, the activation instruction is between a first terminal C^ min and a second terminal Cpr'>max given by the following equations: [°°841 CP,m = Pr-(X-Ni}-Pr-P!l„x [00851 cP,„a= - pr+ (i+A',)-p;+pvm

[0086] with Ps>max representing the maximum power available at the energy storage system 3.

[0087] Thus, for a state of charge SOC above its maximum limit SOCmax, we can choose the minimum value for the setpoint:

[0088] CPr=CFrJ,lln

[0089] For a state of charge SOC below its minimum limit SOCmin, the maximum value can be chosen for the setpoint:

[0090] Cpr = Cp^nax

[0091] Otherwise, when the state of charge is within this range, the setpoint is given by:

[0092] Cp^NP,.

[0093] According to another embodiment, it is possible to fix intermediate points between the two terminals in order to slow down the recharging and discharging of the batteries and to reduce the use of storage.

[0094] Of course, the terminals can be adapted for different dynamic constraints of the electrical production source 2 and of the manager as well as for other settings or services.

[0095] During a step Eli, a second activation instruction for the reserve power of the source is calculated for the subsequent instantaneous value.

[0096] Therefore, it is taken into account in the calculation of the first and second limits that a slope value between a first point corresponding to the activation setpoint CPr' calculated for the current instantaneous value and the activation setpoint calculated for the subsequent instantaneous value is limited, for example by filtering, in order to respect the power variation speed threshold of the source.

[0097] During a step E2, a current instantaneous value Ni' of the source 2 is determined from the setpoint and the reserve power of the power station, for example by dividing the setpoint by the reserve power of this power station 100.

[0098] The frequency adjustment signal of the source N' is then distinguished by its amplitude and its slope compared to the frequency adjustment signal of the central unit N.

[0099] During a step E21, the current instantaneous value Ni' of the source 2 is saturated. Thus, the current instantaneous value of the source is limited in a domain identical to that of the instantaneous value of the power station previously defined by the network manager.

[0100] During a step E3, a power setpoint CP' to be supplied by the source 2 is determined from the unreserved power of the source and the current instantaneous value Ni' of control of the source. This determination takes place for example according to the following equation:

[0101] C^Pç+Nt-P,

[0102] During a step E4, a power setpoint CPs to be supplied by the storage system 3 is determined from a measurement of the power P' supplied by the source 2 and the power setpoint CP of the power plant so as to compensate for a difference between the power supplied by the source and the power setpoint CP of the power plant.

[0103] For example, the power setpoint CPs can be expressed by the following equation:

[0104] CP=Cp-P'

[0105] Thus, the power setpoint CPs is defined as the difference between the value corresponding to what the electrical production source 2 provides and the value of the power P' that the source 2 has actually provided, measured at its output.

[0106] During a step E5, the powers supplied by the source and by the storage system are controlled by the control device respectively from the power setpoint to be supplied by the source and by the storage system.

[0107] It is observed that the preceding equations are parameterized for an example of frequency adjustment but can be adapted for any other type of frequency adjustment or hybrid power plant, in particular according to the dynamic capacities of the source and the power available by the storage system.

[0108] Thus, the method presented makes it possible to respect two constraints while respecting the requirements imposed by the manager at any time, namely:

[0109] - the dynamics of the electrical production source 2; and

[0110] - maintaining the state of charge SOC of the storage system 3 in ac terminals acceptable.

[0111] Furthermore, to ensure that the state of charge SOC is between the two limits, the control strategy implemented by the steps of the method takes into account extreme cases of evolution of the remote control signal. Indeed, the applicant has identified these values ​​as particularly critical because, to ensure that the storage system does not empty over time, it is not only a matter of ensuring that the state of charge is maintained between its terminals at all times, it is also a matter of predicting these extreme cases.

[0112] In this case, another control strategy not taking into account extreme cases is illustrated as an example in [Fig.3] by a causal simulation model.

[0113] In the present description, a causal model is a representation relating input flows and output flows of the model by blocks which generally contain mathematical operations. The input flows are then modified into intermediate flows by the blocks until the output flows are obtained. Thus, it is possible to visualize the input and output flows but also each intermediate flow.

[0114] In this example:

[0115] - block 10 limits the slope of the first derivative of the frequency adjustment signal input N between two terminals worth, in this example, 0.003 and -0.003 in order to obtain the output signal N', and

[0116] - at the output of block 8, the flow contains the product between Pr and N received at the input, and

[0117] - at the output of block 7, the power Ps of the energy storage system 3 contains the difference between the power setpoint CP of the power plant and the power supplied by the source P'.

[0118] However, the applicant noted through this simulation that such a control strategy taking into account only the state of charge SOC is insufficient and inevitably leads to exhaustion of the energy stored in the storage system 3.

[0119] We will now present examples obtained by simulation of the method described above which makes it possible to overcome this problem of exhaustion and, more generally, to highlight the aforementioned advantages. EXAMPLES

[0120] Consider a hybrid power plant 100 with a reserve power Pr equal to 110 MW, comprising an electrical production source 2 embodied by a 500 MW combined cycle gas power plant whose dynamics are limited in increase or decrease to 20 MW per minute and an energy storage system 3 embodied by a 20 MW battery whose initial state of charge SOC is for example between 40% and 60% of the total capacity of the energy storage system 3.

[0121] The power demand P' of the electrical production source 2 is described by the following equation:

[0122] P' = Po+HO-Æ

[0123] Suppose the grid operator wants to request the reserve power of the hybrid power plant Pr worth 110 MW for secondary frequency control in Europe. In other words, the reserve must be fully delivered in 300 seconds at the most.

[0124] The target power limits for activating the reserve for the electrical production source are thus expressed as follows:

[0125] CPrmax- -110+ (1 + Æ) ■ 100+20

[0126] and [°1271 CPr^ 110-100-(1-2V)-20

[0128] The power setpoint of the CPS storage system is expressed as follows:

[0129] CP^PO+1W-NP'

[0130] Starting from the simulation model of the pre-control device 1 not allowing the state of charge of the energy storage system 3 to be maintained, illustrated in [Fig.3], a new causal simulation model allowing this problem to be resolved is illustrated in [Fig.4].

[0131] This simulation model is representative of the implementation of the steps of the control method described above over several iterations.

[0132] In this model, we find:

[0133] constant inputs of the simulation referenced 5,

[0134] variable inputs of the simulation referenced 6,

[0135] blocks referenced 7 corresponding to the addition and subtraction operations between streams containing the values ​​determined upstream in order to obtain downstream the values ​​obtained by these blocks,

[0136] blocks referenced 8 corresponding to the multiplication and division operations between streams containing the values ​​determined upstream in order to obtain downstream the values ​​obtained by these blocks,

[0137] simulation outputs referenced 9, and

[0138] a slope limiter block 11 applying to the value of the first derivative (in other words, the slope) of the setpoint Ca for activating the reserve power of the source in order to respect the source power variation speed threshold.

[0139] There are also blocks 12 and 13 which are tests on the state of charge SOC of the energy storage system 2. If the state of charge SOC is below its minimum limit SOCmin, then the flow at the output of block 12 is equal to 1, otherwise it is equal to 0. If the state of charge SOC is above its maximum limit SOCmax, then the flow at the output of block 13 is equal to 1, otherwise it is equal to 0. Finally, the simulation model also has a block 14 which is a NOR function. When the two flows take the value zero then we are in the case where the state of charge SOC is between its minimum limit SOCmin and its maximum limit SOCmax.

[0140] [Fig.5] illustrates all the active flows of the causal model in the case where the state of charge SOC is between its minimum limit SOCmin and its maximum limit SOCmax

[0141] flow 15 contains the product of the instantaneous values ​​N of control of the power station with the reserve power of the power station Pr after application of a block 7,

[0142] flow 16 contains flow 15 limited in slope by application of block 11 and divided by the reserve power of the power station Pr after application of a block 8, and

[0143] flow 17 contains the CPS power supplied by the storage system after application of blocks 7 and 8 to the variable inputs N, P', Po and to the constant input Pr so as to obtain the equation CPS = Po + 110 ■ N - P'.

[0144] [Fig.6] illustrates all the active flows of the causal model in the case where the state of charge SOC is above its maximum limit SOCmax:

[0145] flow 18 contains the first terminal CPrmin by applying blocks 7 and 8 to the variable input N and to the constant inputs Ps>max, Pr so as to obtain the equation ^,= 110-100-(1-^)-20,

[0146] flow 19 is obtained in a manner analogous to that for flow 16, and

[0147] flow 20 is obtained in a manner analogous to that for flow 17.

[0148] [Fig.7] illustrates the set of active flows between the output and the input in the case where the state of charge SOC is below its minimum limit SOCmin:

[0149] flow 21 contains the second terminal CPr max by applying blocks 7 and 8 to the variable input N and to the constant inputs Ps>max, Pr so as to obtain the equation CPr,m = -110+(l + V)-100 + 20,

[0150] flow 22 is obtained in a manner analogous to that for flows 16 and 19, and

[0151] flow 23 is obtained in a manner analogous to that for flows 17 and 20.

[0152] Figures 9 and 10 illustrate results obtained by simulation by visualization of the outputs at different levels of the causal model.

[0153] These figures show in particular the instantaneous value N for controlling the power plant (curve 24) and the instantaneous value N' for controlling the source (curve 25), the state of charge SOC (curve 26), the power Ps supplied by the storage system (curve 27), the minimum limit SOCmin of the state of charge SOC of the storage system 3 (curve 28), the first terminal CPr ' in (curve 32) and the second terminal CPrmiiX (curve 31) after slope limitation by block 11, as well as the respective parts of the power setpoint CP of the power plant (curve 29) and the power setpoint C p- of the source (curve 30) useful for frequency adjustment.

[0154] In [Fig.9], the state of charge SOC of the energy storage system 3 is between its maximum limit SOCmax and its minimum limit SOCmin, and the output frequency adjustment signal N' follows the input frequency adjustment signal N with an offset corresponding to the slope limit making it possible to respect the dynamics of the electrical production source 2.

[0155] In [Fig. 10], the state of charge SOC of the storage system 3 is below its lower limit SOCmin, which requires a power input from the electrical production source 2 so that the storage system 3 can recharge according to the maximum terminal CPr >max of the activation instruction of the reserve power of the source 2

[0156] Thus, the results illustrated in Figures 9 and 10 confirm that the method stated above allows the storage unit 3 not to exhaust the stored energy over time.

[0157] A variant of the simulation model of [Fig.4] is illustrated in [Fig.8]. Compared to the model of [Fig.4], it further comprises a saturation block 24 interposed between the flow 25 and 26 so as to have the same characteristics as the frequency adjustment signal N sent by the network manager. In other words, so that the flow 26 is between -1 and 1, the flow 25 is saturated between -1 and 1.

[0158] Many modifications can be made without departing from the scope of this presentation.

Claims

1. Claims A method of controlling a hybrid power plant (100), the method comprising at least once implementing the following steps: - considering a power setpoint (CP) of the power plant and a current instantaneous value (Ni) of control of the power plant, the current instantaneous value (Ni) of control of the power plant imposing a speed of variation of a power value of the power plant, the setpoint (Cp) and the current instantaneous value (N 0 aiming to compensate for a difference between a frequency of an electrical network and a nominal frequency of the network, determination (El) of a setpoint (Cft ) of activation of a reserve power (Pr') of an electrical production source (2) of the power plant (100) from a value (SOC) of measurement of a state of charge of an energy storage system (3) of the power plant and taking into account a minimum value and a maximum value which can be taken by a subsequent instantaneous value (Ni+i) of control of the power plant, the reserve power of the source (Pr') being a predetermined power margin of the source,the minimum and maximum values ​​being a function of the current instantaneous value (Ni) of the control unit and of a predetermined threshold of the speed of variation of the current instantaneous value (Ni) of the control unit, the activation instruction being between a first terminal (Cpr- min ) and a second terminal (0^ ^), the first and second terminals being a function of a maximum power (Ps>max) available in the storage system, of the reserve power (Pr) of the power station, of the reserve power (Pr') of the source, of the current instantaneous value (Ni) of control of the power station, of the minimum and maximum values ​​and of a power variation speed threshold of the source; - from the activation instruction (CPr) of the reserve power of the source and a reserve power of the power station (Pr), determination (E2) of a current instantaneous value (N;') of control of the source, the current instantaneous value (N;') of control of the source imposing a speed of variation of a power value of the source, the reserve power (Pr) being a power margin of the power station predetermined; - from a setpoint (CP0) of power excluding reserve of the source and the current instantaneous value (N;') of control of the source, determination (E3) of a power setpoint (CP') to be supplied by the source, the power excluding reserve of the source corresponding to the power supplied by the power station which does not contribute to the frequency adjustment; - from a measurement of the power supplied by the source and the power setpoint (CP) of the power station, determination (E4) of a power setpoint (CPS) to be supplied by the storage system (3) by compensating for a difference between the power supplied by the source and the power setpoint (CP) of the power station; and - control (E5) of a power (P') supplied by the source and of a power (Ps) supplied by the storage system respectively from the power setpoint (CP') to be supplied by the source and the power setpoint (CPS) to be supplied by the storage system.

2. Method according to claim 1, implemented so that the first and second terminals are determined respectively by the following expressions: C^ = / >,-(lW,)- / >;-^ Cpr 'jnax = " P*r + ( 1 + N; ) ' Pt+ Ps^max' with Cpr^njtl the first terminal and Cpr'fljax the second terminal, Pspiax the maximum power available in the storage system, Pr the reserve power of the power station, Pr' the reserve power of the source, and the current instantaneous value.

3. Method according to one of claims 1 or 2, further comprising a (Eli) calculation of a second activation setpoint of the reserve power of the source for the subsequent instantaneous value, the method being implemented so that a slope value between a first point corresponding to the activation setpoint (CPr) calculated for the current instantaneous value and the activation setpoint calculated for the subsequent instantaneous value is limited, for example by filtering, in order to respect the threshold of speed of variation of power of the source.

4. Method according to one of claims 1 to 3, implemented such that a minimum limit of the state of charge is equal to a fraction, for example 40%, of a total capacity of the storage system and that a maximum limit of the state of charge is worth a fraction, for example 60%, of the total capacity of the storage system, and so that the setpoint (Cp / ) for activating the reserve power of the source is equal, if the value (SOC) of measurement of the state of charge is strictly greater than the maximum limit, to the first terminal (Cft ',min) and, if the value (SOC) of measurement of the state of charge is strictly less than the minimum limit, to the second terminal (Cp / ,^).

5. Method according to one of claims 1 to 4, implemented so that the current instantaneous value (Ni) aims to deliver the reserve power in less than 300 seconds, the current instantaneous value (Ni) being between -1 and 1.

6. Method according to one of claims 1 to 4, implemented so that the current instantaneous value (Ni) aims to deliver the reserve power (Pr) of the power station in less than 30 seconds to compensate for the difference between a frequency of an electrical network and a nominal frequency of the network, a value of the nominal frequency of the network being equal to 50.0 Hz and a value of the same difference being equal to -200 millihertz, the current instantaneous value (Ni) being proportional to the same difference.

7. Method according to one of claims 1 to 6, further comprising a step of saturating (E21) the current instantaneous value (N;') of control of the source.

8. Control device (1) of a hybrid power plant (100), the device being configured to implement a method according to one of claims 1 to 7.

9. Computer program product comprising instructions which, when the program is executed by a computer, cause the latter to implement a method according to one of claims 1 to 7.

10. Computer-readable storage means on which a computer program product according to claim 9 is recorded.

11. A hybrid power plant (100) comprising: - a control device (1) of the hybrid power plant according to claim 8; - an electrical production source (2); and - an energy storage system (3), the production source and the storage system being configured to be controlled by the control device.

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