Hybrid power plant and method for controlling a hybrid power plant

Abstract

The present invention relates to a hybrid power plant (100) for producing electricity for a power grid, the hybrid power plant comprising a plurality of energy assets: a first renewable power generation unit, such as a wind turbine generator (WTG1, WTG2); a second renewable power generation unit, such as a plurality of solar power units (PV1, PV2); and an energy storage unit, such as a battery energy storage system (BES). A power plant controller (PPC, 200) is arranged to perform a first comparison (C1) of an active power reference (P_REF,ext, Prefhpp) with an available power (PavailPGS) from the first and second renewable power generation units, and to perform a second comparison (C2) of an available charging or discharging capacity of the energy storage unit with the first comparison. In response to the first comparison, a set point (PrefPGS) is assigned to the first and second renewable power generation units so that electricity is delivered from the hybrid power plant according to the received active power reference (P_REF,ext, Prefhpp).

Description

Technical Field

[0001] The present invention relates to a hybrid power plant having multiple energy assets, the multiple energy assets including several renewable power generation units (including a first renewable power generation unit and a second renewable power generation unit, the first renewable power generation unit including a plurality of first wind turbine generators and the second renewable power generation unit preferably including a solar power unit) and an energy storage unit (such as a large-scale battery). The present invention also relates to a corresponding method, a corresponding controller, and a corresponding computer program product for implementing the present invention. Background Art

[0002] Recently, as a gradual transition to non-fossil-based energy systems has occurred, various renewable energy sources have become increasingly successful in generating electricity for local grids in countries around the world, but grids also have requirements for efficient integration of renewable energy sources.

[0003] For example, the high penetration of wind turbines (or wind turbine generators (WTGs)) in the power grid has triggered requirements for wind turbines regarding how they should contribute to the stability of the grid. Such requirements are included in so-called grid codes defined by transmission system operators (TSOs), and wind power plants (sometimes also called wind farms) must comply with these grid codes in order to produce electricity to the grid.

[0004] Recently, there has been an emerging trend to integrate various renewable energy sources into so-called hybrid power plants that have multiple energy assets, i.e., several power generation units (such as wind turbine generators and solar power units) and energy storage systems (such as large batteries). Due to the potential complementarity of local wind and solar energy sources (for example, when the wind is strong, the sun may not be shining in the evening), it is desirable that the power produced from the hybrid power plant be set to have high reliability.

[0005] Some of the requirements that may be included in the grid code include maintaining certain delivered power, voltage, and frequency, and may have certain limits on the rate of change of these parameters (e.g., so-called ramp rates). These requirements are also expected to be imposed on future hybrid power plants, so it is also important to be able to deliver energy in accordance with the grid code for these hybrid power plants.

[0006] Integrating various power generation sources (e.g., wind and solar) also presents new challenges due to their varying characteristics, particularly their responses to changing conditions and requirements. Generating the maximum allowable amount of energy is also a primary objective, which can be challenging given the various power generation sources and their varying energy production qualities (e.g., stability over time, control over distance within the hybrid power plant, response to changes, etc.).

[0007] Hence, an improved hybrid power plant would be advantageous, and in particular a more efficient and / or more reliable hybrid power plant would be advantageous. Summary of the Invention

[0008] Another object of the present invention is to provide an alternative to the prior art.

[0009] In particular, the object of the present invention may be seen as providing a hybrid power plant that solves the above-mentioned problems of the prior art by producing electricity in compliance with grid regulations, in particular when certain parameters vary, while optimizing energy production.

[0010] Therefore, in a first aspect of the present invention, the above-mentioned and several other objects are achieved by providing a hybrid power plant connected to an associated power grid to produce electricity to the grid, the hybrid power plant comprising a plurality of energy assets, the plurality of energy assets comprising:

[0011] - a first renewable electricity generation unit comprising a plurality of wind turbine generators,

[0012] - a second renewable electricity generation unit, wherein the second renewable electricity generation unit is different from the first renewable electricity generation unit, preferably, the second renewable electricity generation unit comprises a plurality of solar power units, and

[0013] an energy storage unit, preferably a battery energy storage system, capable of storing energy from said first and second renewable electricity generating units and delivering electricity to said grid when required,

[0014] wherein the hybrid power plant further comprises a power plant controller arranged to communicate with a plurality of energy assets, the power plant controller being arranged to receive a real power reference and to perform a first comparison of the real power reference with available power from the first renewable electricity generating unit and the second renewable electricity generating unit, and

[0015] performing a second comparison of the available charge or discharge capacity of an energy storage unit with the first comparison and assigning a corresponding set point to the energy storage unit, and

[0016] The power plant controller is further arranged to, in response to said first comparison, assign set points to said first renewable electricity generating unit and to said second renewable electricity generating unit, respectively,

[0017] In order to deliver power from the hybrid power plant according to the received active power reference.

[0018] The present invention is particularly advantageous for obtaining a hybrid power plant with different renewable power generation units by continuously splitting the active power reference between different sources with fluctuating capabilities, thereby maintaining a stable power output from the hybrid power plant. Simulations carried out by the inventors of the present invention thus show that it is possible to optimize power production while obtaining a stable and fast-responding power plant. With regard to power production, the simulations show that, in certain cases, the implementation of the present invention can increase power production by several percentage points. Another advantage of the present invention is that the power generation units are used to the maximum extent possible, and the batteries are only used when needed. Thus, it is ensured that the hybrid power plant does not curtail the power generation units in the absence of an external reference requirement.

[0019] In the context of the present invention, the term "hybrid power plant" is to be broadly understood as a power plant capable of producing electricity for a power grid based on several energy sources, including but not limited to wind, solar, hydro, thermal, etc., in the sense that a hybrid power plant has a collection of energy sources that produce electricity. It will be understood that the hybrid power plant will be collectively controlled to produce electricity at some overall level of control, which is referred to as a power plant controller (PPC) in the context of the present invention. The various energy assets may additionally or alternatively have some degree of local control (e.g., from a controller). It will also be understood that a hybrid power plant can have a large geographical scope, for example, with various energy assets dispersed across several locations (e.g., separated by up to 2, 5, 10, 15, or 20 km, or even longer), as long as the power plant controller is able to provide some level of overall control in accordance with the present invention (particularly to account for electrical losses and / or control and measurement delays).

[0020] In the context of the present invention, the first renewable electricity generation unit includes a plurality of wind turbine generators, each wind turbine generator (WTG) may include a tower and a rotor having at least one rotor blade (such as three blades). The rotor may be connected to a nacelle that is mounted on top of the tower and is suitable for driving a generator located inside the nacelle. The rotor may rotate under the action of the wind. The rotational energy of the rotor blades caused by the wind is transferred to the generator via a shaft. Therefore, the wind turbine generator is able to convert the kinetic energy of the wind into mechanical energy by means of the rotor blades, and then convert the mechanical energy into electricity by means of the generator. The generator may include a power converter for converting the alternating current of the generator into direct current, and a power inverter for converting the direct current into alternating current to be injected into the power grid. The plurality of wind turbine generators may be different, or they may be of the same kind.

[0021] In the context of the present invention, the second renewable electricity generation unit may include a plurality of solar power units, each of which may have, for example, photovoltaic (PV) solar panels, concentrated solar power (CSP) units or other solar power units capable of utilizing solar radiation and converting it into electricity.

[0022] In the context of the present invention, an energy storage unit is broadly understood as a unit that is capable of storing energy from the first renewable power generation unit and / or the second renewable power generation unit that generates power during periods of excess energy and then storing the energy for a period of time until the energy is needed to be supplied to the power grid.

[0023] Typically, energy storage units can also be used to store energy from the grid during periods when energy is cheaper and release it to the grid when it is more expensive. This is known as "energy arbitrage." Therefore, it will be understood that for a hybrid power plant relying on an energy storage unit, the stored energy must have a certain minimum size to be of any significant use at a later time. Thus, consider a minimum amount of energy stored by the energy storage unit of 0.5MWh, 1MWh, 2MWh, 3MWh, 4MWh, or 5MWh. Similarly, the electricity supplied to the grid may have a certain minimum power, such as at least 0.5MW, 1MW, 2MW, 3MW, 4MW, or 5MW, to comply with relevant grid regulations for power production in order to have an impact on the hybrid power plant. Alternatively, the ratio of the power of the energy storage unit to the total power of the hybrid power plant may be a minimum of 1%, 2%, 3%, 4%, or 5% to have an impact on the grid. Alternatively, the ratio of the power of the energy storage unit to the total power of the hybrid power plant can be a maximum of 20%, 15%, 10%, 8%, 6%, 4% or 2%, because the energy storage unit is typically the most expensive energy asset at a given moment or averaged over a period of time.

[0024] Suitable energy storage units may preferably be based on electrochemical storage such as battery energy storage systems (BES), more preferably comprising rechargeable lithium-ion batteries (LIBs), but other energy storage units are also envisaged within the present invention, for example based on mechanical storage (e.g. compressed air reservoirs), electrical storage (e.g. so-called supercapacitors), thermal energy storage or chemical energy storage (e.g. power-to-gas P2G) or other energy storage devices suitable for power plant energy storage and subsequent power transmission to the grid.

[0025] In the context of the present invention, the charge or discharge capacity of an energy storage unit should be broadly interpreted as a general metric, namely, the amount of charge, and thus energy, stored in the energy storage unit, and / or the discharge or charge rate (such as energy / time), which is generally the function of the storage unit. Note that the discharge or charge rate of an energy storage unit (e.g., a battery) can be dynamic, in that it changes over time as a function of the state of charge (SoC), maximum limits, user-defined limits, etc. Typically, the state of charge (SoC) is measured relatively as a percentage of the total capacity, but other metrics (such as depth of discharge (DoD), which is the opposite of SoC) can also be used. It should be understood that in the context of the present invention, energy storage units generally have relatively high energy storage capacity in order to have a significant impact on the power grid. Therefore, the discharge or charge rate and / or state of charge (SoC) of an energy storage unit can be a combined or aggregate metric of multiple distributed energy storage units (e.g., multiple BESs, whether different, similar, or the same BESs), as will be readily understood by those skilled in the art of energy storage.

[0026] In the context of the present invention, the first renewable power generation unit and the second renewable power generation unit and the energy storage unit can be collectively defined as an energy asset. In one embodiment, other energy assets (particularly fossil fuel (carbon-based) energy assets, such power generation units are based on oil, coal, hydrocarbon gas, etc.) can work in conjunction with the energy assets of the present invention. In this technical field, energy assets can also be referred to as "energy actuators", as will be readily understood by those skilled in the art. These two terms will be used interchangeably in the detailed description below.

[0027] Similarly, in the context of the present invention, the first energy asset can be considered as a first renewable power generation unit. The first renewable power generation unit can then include a plurality of wind turbine generators (WTGs). These wind turbine generators can then have shared or common characteristics, such as a plurality of very similar or identical wind turbine generators in a large wind turbine array or wind farm. Similarly, the second energy asset can be considered as a second renewable power generation unit. The second renewable power generation unit can then include a plurality of solar power units. These solar power units can then have shared or common characteristics, such as a plurality of very similar or identical solar power units (e.g., PV units) in a large solar array.

[0028] Available power is understood to be the power that a renewable electricity generation unit is capable of producing. Available power may vary over time. For a wind turbine generator, it may depend on wind speed and / or wind direction, and for a solar power unit, it may depend on solar irradiance.

[0029] In one embodiment, when the result of the first comparison of the active power reference and the available power is that the active power reference is greater than the available power, thereby indicating a power deficit, the power plant controller is arranged to assign a corresponding set point to the energy storage unit depending on the second comparison, so as to at least partially compensate for the power deficit by discharging the energy storage unit.

[0030] In another related embodiment, the second comparison may indicate that the available charging or discharging capacity from the energy storage unit is sufficient to compensate for the power deficit indicated by the first comparison, and the power plant controller is arranged to assign a corresponding set point to the energy storage unit so as to produce the required power in an advantageous manner.

[0031] In a further embodiment, wherein the second comparison may indicate that the available charging or discharging capacity from the energy storage unit is insufficient to compensate for the power deficit indicated by the first comparison, and the power plant controller is arranged to assign a corresponding set point to the energy storage unit to compensate for the power deficit as much as possible by the available charging or discharging capacity.

[0032] In one embodiment, the power plant controller may further be arranged to assign a setpoint to the first renewable power generation unit and / or the second renewable power generation unit, respectively, that is higher than the otherwise indicated available power from the first renewable power generation unit and / or the second renewable power generation unit. Thus, the present invention is particularly advantageous in that the renewable power generation units may produce higher levels of power than would otherwise be expected, as the inherent instability of the sun and wind makes it difficult to estimate or reliably measure the available power. Simulations have shown an expected percentage increase, which is a significant result. Consequently, despite modern control loops having millisecond response times, the available power from the renewable power generation units may be delayed by several seconds. It will of course be understood that even though the setpoint may be set higher than the otherwise indicated available power, the safety limits of the renewable power generation units should be adhered to and not overridden.

[0033] In a particularly advantageous embodiment, the hybrid power plant can have a set point above the indicated available power independently of said second comparison.

[0034] In another particularly advantageous embodiment, the set point for each of the first renewable power generation unit and / or the second renewable power generation unit can be equal to the active power reference. In other embodiments, the set point is set to 10%, 20%, or 30% higher than the active power reference, etc., but of course still respecting the safety limits of the renewable power generation units. In some variations, there can also be a reallocation between wind turbine generators and solar power unit energy assets and during situations where they would operate beyond their available limits. As will be understood by those skilled in the art, various control loops (feedback or feedforward) can attempt to further optimize this over time.

[0035] In another embodiment, when the result of the first comparison of the active power reference and the available power is that the active power reference is less than the available power, thereby indicating a power surplus, the power plant controller can be arranged to assign a corresponding set point to the energy storage unit depending on the second comparison, so as to charge the energy storage unit as much as possible to reuse the energy at a later time.

[0036] In another related embodiment, the power plant controller (PPC) may be arranged to assign a corresponding set point to the energy storage unit to charge the energy storage unit using all or part of the charging capacity of the energy storage unit depending on the second comparison, and may be configured to assign the corresponding set point to the first renewable power generation unit and the second renewable power generation unit, respectively.

[0037] In another embodiment, the power plant controller (PPC) may be further arranged to assign set points to the first renewable power generation unit and the second renewable power generation unit, respectively, in response to the second comparison, so as to deliver power from the hybrid power plant according to the received active power reference, i.e., in case of excess power, the set points for the renewable power generation units may also depend on the second comparison.

[0038] In some embodiments, a hybrid power plant reference may be calculated based on a desired operating mode of the hybrid power plant using an active power reference, preferably from a transmission system operator (TSO), and using a hybrid active power controller, and the power plant controller is arranged to perform a first comparison of the hybrid power plant reference with the available power from the first and second renewable power generation units. Thus, by converting to a local hybrid power plant reference, more improved control may be performed.

[0039] In some embodiments, the available power from the first renewable power generation unit and / or the second renewable power generation unit can be based at least in part on meteorological conditions and / or forecasts, including wind conditions and / or forecasts for the first renewable power generation unit and preferably solar conditions and / or forecasts from the second renewable power generation unit, to provide a more accurate forecast of the available power. Alternatively or additionally, the available power can include elements or features from previous measurements or a history of measurements at the same location and / or under similar circumstances.

[0040] In some embodiments, the hybrid power plant may further include:

[0041] - a module for deriving estimates of electrical losses in a hybrid power plant;

[0042] - means for deriving a measure of electrical losses in the hybrid power plant based on the difference between the total power production from the plurality of energy assets and the power measurement at the point of common coupling (PoC), and

[0043] a regulator arranged to apply the estimated values ​​of the electrical losses and the measured values ​​of the electrical losses in an active power control loop of a power plant controller, said active power control loop being arranged to control the active power production of the hybrid power plant at the point of common coupling,

[0044] The available power from the first renewable electricity generation unit and / or the second renewable electricity generation unit is calculated using the regulator. Thus, if the estimated value of the power may differ from the actual measured value, for example due to electrical losses, this embodiment can compensate for and / or reduce it, resulting in an even better value for the available power.

[0045] In a second aspect, the present invention relates to a method for controlling a hybrid power plant connected to an electrical grid to produce electricity for the grid, the hybrid power plant comprising a plurality of energy assets, the plurality of energy assets comprising:

[0046] - a first renewable electricity generation unit comprising a plurality of wind turbine generators,

[0047] - a second renewable electricity generation unit, wherein the second renewable electricity generation unit is different from the first renewable electricity generation unit, preferably, the second renewable electricity generation unit comprises a plurality of solar power units, and

[0048] an energy storage unit, preferably a battery energy storage system, capable of storing energy from said first and second renewable electricity generating units and delivering electricity to said grid when required,

[0049] The method comprises:

[0050] - controlling a power plant controller (PPC) to communicate with a plurality of energy assets, said power plant controller being arranged to receive a real power reference,

[0051] - performing a first comparison of said active power reference with the available power from said first renewable electricity generating unit and said second renewable electricity generating unit,

[0052] - performing a second comparison of the available charging or discharging capacity of the energy storage unit with the first comparison and assigning a corresponding set point to the energy storage unit, and

[0053] - in response to said first comparison, allocating set points to said first renewable electricity generating unit and to said second renewable electricity generating unit, respectively, in order to deliver electricity from the hybrid power plant according to the received active power reference.

[0054] In a third aspect, the present invention relates to a power plant controller (PPC) for controlling an associated hybrid power plant connected to an associated power grid to produce power to the grid, the hybrid power plant comprising a plurality of energy assets, the plurality of energy assets comprising:

[0055] - a first renewable electricity generation unit comprising a plurality of wind turbine generators,

[0056] - a second renewable electricity generation unit, wherein the second renewable electricity generation unit is different from the first renewable electricity generation unit, preferably, the second renewable electricity generation unit comprises a plurality of solar power units, and

[0057] an energy storage unit, preferably a battery energy storage system, capable of storing energy from said first and second renewable electricity generating units and delivering electricity to said grid when required,

[0058] wherein the power plant controller is arranged to communicate with a plurality of energy assets, the power plant controller being arranged to receive a real power reference and to perform a first comparison of the real power reference with available power from the first and second renewable electricity generating units, and

[0059] performing a second comparison of an available charging or discharging capacity of an energy storage unit with the first comparison and assigning a corresponding set point to the energy storage unit, and the power plant controller is further arranged to assign set points to the first renewable electricity generating unit and the second renewable electricity generating unit, respectively, in response to the first comparison,

[0060] In order to deliver power from the hybrid power plant according to the received active power reference.

[0061] In a fourth aspect, the invention relates to a computer program product adapted to enable a computer system to control a hybrid power plant according to the first and / or second aspects of the invention, the computer system comprising at least one computer having data storage means connected thereto.

[0062] A particular but non-exclusive advantage of this aspect of the invention is that the invention may be implemented by a computer program product which, when downloaded or uploaded to a computer system, causes the computer system to perform the operations of the second aspect of the invention.

[0063] In another aspect, the invention relates to a data storage medium on which such a computer program product may be provided, ie the computer program product may be provided on any kind of computer readable medium or over a network.

[0064] Each aspect of the invention may be combined with any other aspect.These and other aspects of the invention will become apparent from the following description with reference to the described embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The present invention will now be described in more detail with reference to the accompanying drawings, which illustrate one way of implementing the invention and are not to be construed as limiting other possible embodiments that fall within the scope of the appended claims.

[0066] Figure 1 is a simplified schematic diagram of a power plant controller of a hybrid power plant according to an embodiment of the present invention,

[0067] Figure 2 is a schematic flow chart showing an outline of the present invention,

[0068] Figure 3 is a schematic diagram of a hybrid power plant according to another embodiment of the present invention,

[0069] FIG4 is a more detailed diagram of a hybrid power plant according to another embodiment of the present invention,

[0070] Figure 5 is a schematic diagram of energy assets in the case of excess power.

[0071] Figure 6 is a schematic diagram of energy assets under power shortage conditions.

[0072] Figure 7-9 A simulation diagram showing three different situations (called use cases 1, 2 and 3) of a hybrid power plant according to the present invention, and

[0073] Figure 10 is a schematic system diagram showing an overview / details of the operation of the computer program product according to the present invention or the method according to the present invention. DETAILED DESCRIPTION

[0074] Figure 1 is a simplified schematic diagram of a power plant controller (PPC) 200 of a hybrid power plant according to an embodiment of the present invention.

[0075] Hybrid power plant 100 (see Figure 3 and Figure 4) include arrangements for various energy assets ( Figure 1 The power plant controller PPC 200 communicates with the power plant controller (not shown), which is arranged to preferably receive the active power reference PREF,ext from the transmission system operator (TSO) and use the hybrid active power controller 210 to calculate the hybrid power plant reference Prefhpp based on, for example, the desired operating mode of the hybrid power plant (such as frequency control, active power reduction, etc.).

[0076] The power plant controller (PPC) 200 is further arranged to assign, in response to the first comparison, set points PrefPGS, PS_1, PS_2 (and in particular Pset1 ... Pset,n) to the first and second renewable power generating units, and to assign one or more corresponding set points PS_3, PrefESS (more in particular Pset,ess1 ... Pset,essn) to the energy storage units ESU (see Figure 3 -4) in order to deliver power from the hybrid power plant according to the received active power reference PRE_REF,ext, which is as follows Figure 1 As shown, it is converted into Prefhpp. The hybrid dispatcher 220 receives the Prefhpp control signal and calculates the PrefPGS control signal for the power generation unit and the PrefESS control signal for the energy storage unit or system ESS. Then, at the next level, the PrefPGS signal is distributed or dispatched to each power generation unit (such as WTG or PV) using the PGS dispatcher 230. Similarly, the PrefESS signal is then distributed or dispatched to the energy storage units (such as multiple batteries) in the lower level using the ESS dispatcher 240.

[0077] Figure 2 It is a schematic flow chart showing the outline of the present invention.

[0078] The power plant controller 200 is configured to perform a first comparison C1 of the hybrid power plant reference Prefhpp with the available power PavailPGS measured and / or estimated from the first renewable power generation unit EA1, 1RPGU and the second renewable power generation unit EA2, 2RPGU to calculate whether the power generation units have excess or deficit power. Whether to calculate excess power as a plus sign "+" and deficit power as a minus sign "-" is a matter of mathematical convenience or convention and does not alter the application and principles of the present invention. Alternatively, only numerical differences may be applied. Essentially, when the available power from the power generation units is greater than the power plant active power reference Prefhpp, there is excess power, as indicated by the lower branch of the flow chart. Conversely, when the available power from the power generation units is less than the hybrid power plant active power reference Prefhpp, there is a power deficit, as indicated by the upper branch of the flow chart. This is determined in the second comparison, resulting in branches C2a: deficit power and C2b: excess power.

[0079] Excess power

[0080] If excess power is available from the power generation unit, as much of the excess power as possible will be used to charge the energy storage system (ESS) or energy storage unit (ESU). The actual amount of excess power used to charge the ESS depends on the current total charging capacity of the ESS. The ESS's charging capacity ("ChargeCap") depends on its current state, which is based on feedback information (such as maximum charging power, state of charge (SoC), etc.) and user preferences (such as maximum charge setpoint, frequency control permissions, reserved charging, etc.).

[0081] If the total charging capacity is greater than the excess power, all the excess power will be used for charging. If the total charging capacity is less than the excess power, the excess power used for charging will be limited to the charging capacity.

[0082] In case of multiple BESs for example, each BES will be assigned a set point Pset,ess based on user specified settings (such as priority, percentage weight, charging capability share, state of charge, etc.).

[0083] The charging setpoint may be overruled by a manual charging request that exceeds the excess power, meaning that the active power reference of the hybrid power plant cannot be met. This is intended to allow forced charging of the ESS by the user, for example, when electricity prices are low.

[0084] Insufficient power

[0085] If the power from the power generation system is insufficient, the insufficient power is compensated by discharging the ESS as much as possible. The actual amount of insufficient power that can be compensated by discharging the ESS depends on the current total discharge capacity of the ESS. The discharge capacity of the ESS depends on its current state, which is based on feedback information (such as maximum discharge power, state of charge (SoC), etc.) and user preferences (such as maximum discharge set point, F-Ctrl permission, reserved discharge, etc.). If the total discharge capacity is greater than the insufficient power, all insufficient power is compensated by discharge. If the total discharge capacity is less than the insufficient power, all discharge capacity is used. In the case of multiple ESSs, SP is allocated to each ESS based on user-specified settings (such as priority, percentage weight, charging capacity share, charging state, etc.).

[0086] In case there is excess power available for charging, the total charging set point will indicate the charging requested due to the power surplus and must later be added to the plant active power reference:

[0087] PrefPGS=Prefhpp+PrefESS

[0088] In case no charging setpoint is set (due to insufficient power, i.e. in the upper branch of the flow chart), the plant active power setpoint will simply be assigned as:

[0089] PrefPGS=Prefhpp

[0090] This is done so that the first and second power generation units generate at most Prefhpp power whenever possible, as it is not desirable to discharge the ESS more than necessary. PrefPGS will then be the reference that the power generation unit or system must compensate for. In the case of multiple power generation units, the allocation of set points to the various power generation units is done based on user-specified settings such as priority, percentage weight, available power weight, etc. Additionally or alternatively, the set points may be limited due to other circumstances, such as limitations on rated power.

[0091] Figure 3 FIG2 is a schematic diagram of a hybrid power plant according to another embodiment of the present invention. The hybrid power plant 100 is connected to an associated power grid 1000 to generate electricity for the grid, and includes a plurality of energy assets EA1, EA2 and EA3.

[0092] Thus, a first renewable power generation unit EA1 or 1RPGU is part of the power plant 100, i.e., in this embodiment, a plurality of wind turbine generators WTG1 and WTG2, and a second renewable power generation unit EA2, 2RPGU, i.e., in this embodiment, a plurality of solar power units PV1 and PV2. For simplicity, only two wind turbine generators and solar power units are shown in this embodiment, but a person skilled in the art will of course understand that, in principle, any number of renewable power generation units is contemplated within the teachings and principles of the present invention.

[0093] Additionally, an energy storage unit ESU or system ESS is part of the power plant 100, which is preferably a battery energy storage system BES capable of storing energy from the first and second renewable electricity generating units (i.e. from the wind turbine generators WTG1 and WTG2, and the solar power units PV1 and PV2), and the energy storage unit is arranged to deliver electricity to the grid 1000 when needed. The energy storage unit is indicated as a third energy asset EA3.

[0094] The hybrid power plant 100 further comprises a power plant controller (PPC) 200 which is arranged to communicate with the various energy assets, i.e. to receive information about their status / condition and generally to send control signals to each of them, and the power plant controller is in particular arranged to receive an active power reference provided, for example, by a grid operator (as shown on the left side of the PPC) and to distribute active power setpoints P_S1, P_S2 and P_S3 to the various energy assets, as shown Figure 1 and Figure 3 As an intermediate control signal, the hybrid power plant reference Prefhpp is also used. It may be mentioned that in some embodiments the WTG dispatcher may form part of the controller PPC 200. P_REF is a reference received from the grid operator (TSO) (i.e. Figure 1 The power plant controller 200 may include a reference such as Pref, ext in , or received from the user, but it may also come from another controller (such as a frequency controller indicated by the signal name Pref_freq_ctrl). Figure 3 Schematically indicated in FIG are a wind turbine generator WTG dispatcher 230a, a PV dispatcher 230b and a BES dispatcher 240.

[0095] Typically, it is expected that the PPC 200 will communicate directly with WTG1 and WTG2, and that it will communicate with the energy storage BES and PV1 and PV2 through dedicated BES and PV controllers (similar to the power plant controller PPC, but specialized for PV and BES). These dedicated controllers will then distribute set points to the individual PV array converters or individual ES converters (i.e., PV and ES systems are composed of multiple units, just like wind power plant systems). In the embodiment shown, the controller PPC 200 communicates via a set point splitter (SPLITTER), which then further distributes the set points PS_1, PS_2, and PS_3 to dispatchers for each energy asset.

[0096] It is also conceivable that the setpoints may be distributed to the WTGs via local controllers, i.e., one master PPC distributes the setpoints to one or more slave PPCs, for example, for a large wind turbine park with a large number of wind turbine generators (such as more than 20 wind turbine generators, or more than 40 wind turbine generators).

[0097] FIG4 is a more detailed diagram of a hybrid power plant according to another embodiment of the present invention. FIG4 ( Figure 4A and Figure 4B ) is a schematic diagram of a hybrid power plant according to another embodiment of the present invention. Figure 3In addition to the hybrid power plant shown, hybrid power plant 100 also includes a module 310 for deriving an estimate of the electrical losses in the hybrid power plant. Furthermore, there is a module 320 for deriving a measured value of the electrical losses in the hybrid power plant based on the difference between the total power production Pprod from a plurality of energy assets (here EA1 is a WTG actuator, EA2 is a PV actuator, and EA3 is a BES actuator) and the power measurement Pmeas at the point of common coupling (PoC) of power grid 1000. Furthermore, the power plant controller includes a regulator 300 as an active power controller, which is arranged to apply this estimate of the electrical losses and the measured value of the electrical losses to an active power control loop of power plant controller 200, which is arranged to control the active power production of hybrid power plant 100 at the point of common coupling.

[0098] FIG5 is a schematic diagram of energy assets in a power surplus situation.

[0099] Therefore, in Figure 5A In the embodiment, a comparison is first performed (as indicated by circle 1) in order to determine whether the active power reference PREF,ext or more specifically the hybrid power plant reference Prefhpp is greater than or less than the available power PavailPGS from the first renewable power generation unit EA1,1RPGU and the second renewable power generation unit EA2,2RPGU (see Figure 3 and Figure 4). In this case, it can be seen that the available power PavailPGS is larger, and then the excess power can be stored as much as possible. Figure 5A In the example shown in FIG2 , a second comparison (as indicated by circle 2 ) is performed between the available charging or discharging capacity of the energy storage unit EA3, ESU (e.g. indicated by the state of charge) and the result of the first comparison (i.e. the excess power), which indicates that the available charging of the energy storage unit is higher than the excess power, so all the excess power can be stored for later use. Therefore, the excess power from the first renewable electricity generation unit and the second renewable electricity generation unit will be stored, as shown in FIG2 . Figure 5A As schematically indicated in the rightmost column.

[0100] In another case, such as Figure 5B As shown, first a comparison is performed (as indicated below circle 1) in order to determine whether the active power reference PREF,ext or more specifically the hybrid power plant reference Prefhpp is greater than or less than the available power PavailPGS (see FIG. Figure 3and Figure 4). In this case, we see again that the available power PavailPGS is larger and some of the excess power can then be stored. Figure 5B In the embodiment, a second comparison is again made between the available charging or discharging capacity (e.g., state of charge) of the energy storage unit EA3, ESU and the result of the first comparison (i.e., excess power), which second comparison indicates that the possible charging of the energy storage unit is lower than the excess power, and therefore only a limited amount of excess power can be stored for later use.

[0101] Therefore, a limited amount of excess power from the first renewable electricity generating unit and the second renewable electricity generating unit will be stored, as Figure 5B Therefore, the power plant controller PPC 200 then distributes the set points PrefPGS, PS_1, PS2 to the first renewable power generating unit EA1, 1RPGU and the second renewable power generating unit EA2, 2RPGU, respectively, in order to deliver power from the hybrid power plant according to the received active power reference PREF,ext or Prefhpp, the PrefPGS control signal being lower than the available power PavailPGS, as schematically indicated.

[0102] FIG6 is a diagram of energy assets in a power shortage situation similar to the diagram in FIG5. Figure 6A and Figure 6B In the example, a comparison is first performed (as indicated below circle 1) in order to determine whether the active power reference PREF,ext or more specifically the hybrid power plant reference Prefhpp is greater than or less than the available power PavailPGS from the first renewable power generation unit EA1, 1RPGU and the second renewable power generation unit EA2, 2RPGU (see Figure 3 and Figure 4). However, in Figure 6A and Figure 6B In both cases, there is a power shortage situation, where the available power is lower than the desired power demand represented by the control signal Prefhpp.

[0103] exist Figure 6AIn the example, a second comparison is performed again between the available state of charge of the energy storage unit EA3, ESU, and the result of the first comparison (i.e., the power deficit). This second comparison indicates that the possible discharge of the energy storage unit is greater in value than the power deficit (as indicated below circle 2). Therefore, by discharging the ESU, the power gap can be bridged by causing a corresponding discharge of the ESU, thereby generating the required power Prefhpp from the hybrid power plant. However, in a particularly advantageous embodiment of the present invention, the set point PrefPGS of the power generation system is set to be equal to the Prefhpp level or to be lower than Prefhpp by a predetermined amount (e.g., 10%, 20%, 30%, 40%, or 50%) in order to generate more power than required and / or possibly generate power in a more stable manner.

[0104] exist Figure 6B In the example shown in FIG2 , the second comparison shows that the possible discharge of the energy storage unit ESU is numerically less than the insufficient power (as indicated below circle 2). Therefore, even if the energy storage unit is discharged to the maximum extent, the hybrid power plant cannot generate sufficient power. However, in another particularly advantageous embodiment of the present invention, the set point PrefPGS of the power generation system is set equal to Prefhpp or lower than Prefhpp by a predetermined amount (e.g., 10%, 20%, 30%, 40%, or 50%) in order to generate more power than required and / or possibly generate power in a more stable manner.

[0105] Figure 7-9 Simulation diagrams are shown for three different situations of a hybrid power plant 100 according to the invention, referred to as use cases 1, 2 and 3. The vertical axis is arbitrary power units (pu) and the horizontal axis is the measurement time (in seconds).

[0106] Figure 7"Use Case 1" illustrates the allocation of power between hybrid energy assets, including a wind turbine generator ("Turbine"), a solar power unit ("PV"), and an energy storage unit ("Battery"), with the wind turbine generator receiving priority over the solar power unit. First, the power plant controller transmits a setpoint of approximately 0.55 pu at approximately 10 seconds, indicating that the hybrid power plant begins delivering power to the grid (Pref,ext, above zero pu). Later (approximately 50 seconds), the hybrid power plant receives a Pext,ref of approximately 1 pu, indicating that total power production should increase to a higher level. The power plant controller (PPC) then allocates a setpoint of approximately 0.6 pu to the wind turbine generator (see sub-figure "Turbine"). It can be seen that the WTG reacts to this new setpoint within a few seconds. Meanwhile, the PV unit (see sub-figure "Solar") is gradually ramping up from a state of no power production to a level slightly below 0.3 pu. It can be seen that the PV unit ramps up more slowly than the WTG, requiring approximately 25 seconds to reach the desired setpoint. At approximately 50 seconds, the energy storage unit (see sub-figure “Battery”) changes from a negative power production of approximately -0.4 pu (i.e., the battery is being charged due to excess power) to a situation where the battery delivers slightly less than 0.04 pu to the total power production of the hybrid power plant. It can be seen that the total power production (Pmeas) of the hybrid power plant (see sub-figure “Power Plant”) can respond relatively quickly to the required changes in the external active power reference Pref,ext, even if the various energy assets have different response characteristics (e.g. Figure 7 shown).

[0107] Figure 8 is similar to Figure 7 , but instead, an equal weight (50%) is assigned between the various energy assets (the wind turbine generator "Turbine" and the solar power unit "Solar"). Thus, first, the WTG (see sub-graph "Turbine") drops from a maximum production of approximately 0.55 pu to slightly below 0.3 pu, and at a time of approximately 50 seconds, the power production of the wind turbine generator rises to approximately 0.6 pu, while at the same time the PV unit increases from approximately 0.25 pu to slightly below 0.3 pu, and the energy storage unit (see sub-graph "Battery") again changes from a negative power production of approximately -0.4 pu (i.e., the battery is being charged) to a situation where the battery delivers slightly below 0.04 pu by discharging accordingly.

[0108] Figure 9This is the case where initially there is a power surplus and the battery (see sub-figure "Battery") is being charged, i.e. a negative power production of approximately -0.4 pu. Subsequently, at approximately 50 seconds another situation occurs where the hybrid power plant is unable to fully deliver the required power represented by the received Pref,ext signal compared to PavailPGS and the discharge capacity of the energy storage unit is approximately 0.04 pu, so that the power from the hybrid power plant is insufficient. Despite this, the full reference PrefPGS is still sent or dispatched to the power generation systems (see sub-figures "Turbine" and "Solar") even though they have a limited available power PavailPGS. Therefore, by dispatching such a set point or control signal to the power generation system, more power is actually generated than is considered available, the reason for which is related to the difficulty of reliably estimating or measuring the available power from a power generation system based on renewable energy sources. This is a particularly advantageous embodiment of the invention: even if the desired power Pref,ext cannot be fully produced after 50 seconds, the power harvested from the hybrid power plant exceeds the expectations of Pmeas (higher than PavailPGS and Pprod,ess).

[0109] Figure 10 is a schematic system diagram showing an overview / details of the operation of a computer program product according to the present invention or a method according to the present invention. Thus, a method for controlling a hybrid power plant 100 connected to an electrical grid 100 to produce electricity to said grid, the hybrid power plant comprising a plurality of energy assets, said plurality of energy assets EA1, EA2 and EA3 (see Figure 3 and Figure 4) include:

[0110] - a first renewable electricity generation unit EA1, 1RPGU comprising a plurality of wind turbine generators WTG1, WTG2,

[0111] -Sb second renewable power generation unit EA2, 2RPGU, wherein the second renewable power generation unit is different from the first renewable power generation unit, preferably, the second renewable power generation unit comprises a plurality of solar power units PV1, PV2, and

[0112] - Sc an energy storage unit EA3, ESU, preferably a battery energy storage system BES, said energy storage unit being able to store energy from said first and second renewable electricity generating units and to deliver electricity to said grid when needed,

[0113] The method includes:

[0114] S1 controls a power plant controller (PPC) 200 to communicate with various energy assets, the power plant controller being arranged to receive active power references PREF,ext, Prefhpp,

[0115] S2 performs a first comparison C1 of said active power reference PREF,ext or Prefhpp with the available power PavailPGS from said first renewable power generating unit EA1,1RPGU and said second renewable power generating unit EA2,2RPGU (see Figure 2 ),

[0116] S3 performs a second comparison C2a, C2b of the available charging or discharging capacity of the energy storage unit EA3, ESU with the first comparison and assigns a corresponding set point PS_3, PrefESS to the energy storage unit EA3, ESU, and

[0117] In summary, the present invention relates to a hybrid power plant 100 for producing electricity for a power grid, the hybrid power plant comprising a plurality of energy assets: a first renewable power generation unit (such as wind turbine generators WTG1, WTG2); a second renewable power generation unit (such as a plurality of solar power units PV1, PV2); and an energy storage unit (such as a battery energy storage system BES). The power plant controller PPC 200 is arranged to perform a first comparison C1 of an active power reference PREF,ext, Prefpp with an available power PavailPGS from the first and second renewable power generation units, and to perform a second comparison C2 of an available charging or discharging capacity of the energy storage unit with the first comparison (see Figure 1 and Figure 2 In response to the first comparison, a set point PrefPGS is assigned to the first and second renewable power generating units in order to deliver power from the hybrid power plant according to the received active power reference PREF,ext or Prefhpp (see Figure 3 and Figure 4).

[0118] The present invention may be implemented by means of hardware, software, firmware or any combination thereof. The present invention or certain features thereof may also be implemented as software running on one or more data processors and / or digital signal processors.

[0119] The various elements of the embodiments of the present invention may be implemented physically, functionally, and logically in any suitable manner, such as in a single unit, in multiple units, or as part of an independent functional unit. The present invention may be implemented in a single unit, or may be physically and functionally distributed between different units and processors.

[0120] Although the present invention has been described in conjunction with specific embodiments, the present invention should not be interpreted as being limited in any way to the examples given. The scope of the present invention will be interpreted in accordance with the appended claims. In the context of the claims, the term "comprising" does not exclude other possible elements or steps. In addition, references such as "one" or "an" should not be interpreted as excluding a plurality. The use of reference numerals in the claims with respect to elements indicated in the drawings should not be interpreted as limiting the scope of the present invention. In addition, individual features mentioned in different claims may be advantageously combined, and mentioning these features in different claims does not exclude that a combination of features is impossible and advantageous.

Claims

1. A hybrid power plant connected to an associated power grid (1000) to produce electricity for the grid, the hybrid power plant comprising a plurality of energy assets, the plurality of energy assets (EA1, EA2, EA3) comprising: - a first renewable electricity generation unit (EA1, 1RPGU) comprising a plurality of wind turbine generators (WTG1, WTG2), - a second renewable electricity generating unit (EA2, 2RPGU), wherein the second renewable electricity generating unit is different from the first renewable electricity generating unit, and an energy storage unit (EA3, ESU) capable of storing energy from the first and second renewable electricity generation units and delivering electricity to the grid when needed, wherein the hybrid power plant further comprises a power plant controller (PPC, 200) arranged to communicate with the plurality of energy assets, the power plant controller being arranged to receive an active power reference (P_REF,ext, Prefhpp) and to perform a first comparison of the active power reference (P_REF,ext, Prefhpp) with an available power (PavailPGS) from the first renewable power generating unit (EA1, 1RPGU) and the second renewable power generating unit (EA2, 2RPGU), and performing a second comparison of the available charging or discharging capacity of the energy storage unit (EA3, ESU) with the first comparison and assigning a corresponding set point (PS_3, PrefESS) to the energy storage unit (EA3, ESU), and The power plant controller (PPC, 200) is further arranged to distribute set points (PrefPGS, PS_1, PS2) to the first renewable power generating unit (EA1, 1RPGU) and the second renewable power generating unit (EA2, 2RPGU), respectively, in response to the first comparison, so as to deliver power from the hybrid power plant according to the received active power reference (P_REF,ext, Prefhpp), wherein, when the result of the first comparison of the active power reference (P_REF, ext, Prefhpp) with the available power (PavailPGS) is that the active power reference (P_REF, ext, Prefhpp) is greater than the available power (PavailPGS), thereby indicating a power shortage, the power plant controller (PPC, 200) is arranged to assign a set point (PrefPGS, PS_1, PS2) that is higher than the additionally indicated available power (PavailPGS) from the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU), respectively, to the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU).

2. The hybrid power plant according to claim 1, wherein: When the result of the first comparison of the active power reference (P_REF,ext, Prefhpp) with the available power (PavailPGS) is that the active power reference (P_REF,ext, Prefhpp) is greater than the available power (PavailPGS), thereby indicating a power shortage, the power plant controller (PPC, 200) is arranged to assign a corresponding set point (PS_3, PrefESS) to the energy storage unit (EA3, ESU) depending on the second comparison, so as to at least partially compensate for the power shortage by discharging the energy storage unit.

3. The hybrid power plant according to claim 2, wherein: The second comparison indicates that the available charging or discharging capacity from the energy storage unit (EA3, ESU) is sufficient to compensate for the power shortage indicated by the first comparison, and the power plant controller (PPC, 200) is arranged to assign a corresponding set point (PS_3, PrefESS) to the energy storage unit (EA3, ESU).

4. The hybrid power plant according to claim 2, wherein: The second comparison indicates that the available charging or discharging capacity from the energy storage unit (EA3, ESU) is insufficient to compensate for the power shortage indicated by the first comparison, and the power plant controller (PPC, 200) is arranged to assign a corresponding set point (PS_3, PrefESS) to the energy storage unit (EA3, ESU) to compensate for the power shortage as much as possible by the available charging or discharging capacity.

5. The hybrid power plant according to claim 1, wherein: The setpoints (PrefPGS, PS_1, PS2) that are higher than the indicated available power (PavailPGS) are independent of the second comparison.

6. The hybrid power plant according to claim 5, wherein: The set points (PrefPGS, PS_1, PS2) for the first renewable power generating unit (EA1, 1RPGU) and the second renewable power generating unit (EA2, 2RPGU), respectively, are equal to the active power reference (P_REF,ext, Prefhpp).

7. The hybrid power plant according to claim 1, wherein: When the result of the first comparison of the active power reference (P_REF,ext, Prefhpp) with the available power (PavailPGS) is that the active power reference (P_REF,ext, Prefhpp) is less than the available power (PavailPGS), thereby indicating a power surplus, the power plant controller (PPC, 200) is arranged to assign a corresponding set point (PS_3, PrefESS) to the energy storage unit (EA3, ESU) depending on the second comparison, so as to charge the energy storage unit as much as possible.

8. The hybrid power plant according to claim 7, wherein: The power plant controller (PPC, 200) is arranged to assign a corresponding set point (PS_3, PrefESS) to the energy storage unit (EA3, ESU) depending on the second comparison so as to charge the energy storage unit with all or part of its charging capacity, and is arranged to assign a corresponding set point (PrefPGS, PS_1, PS2) to the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU), respectively.

9. The hybrid power plant according to claim 7 or 8, wherein: The power plant controller (PPC, 200) is further arranged to assign set points (PrefPGS, PS_1, PS2) to the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU), respectively, in response to the second comparison, so as to deliver power from the hybrid power plant according to the received active power reference (P_REF,ext, Prefhpp).

10. The hybrid power plant according to claim 1, in, The power plant controller is arranged to receive an active power reference (P_REF,ext) from a transmission system operator (TSO) and calculate a hybrid power plant reference (Prefhpp) based on a desired operating mode of the hybrid power plant using a hybrid active power controller (210), and the power plant controller is arranged to perform a first comparison of the hybrid power plant reference (Prefhpp) with the available power (PavailPGS) from the first renewable power generating unit (EA1, 1RPGU) and the second renewable power generating unit (EA2, 2RPGU).

11. The hybrid power plant according to claim 1, in, The available power (PavailPGS) from the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU) is at least partially based on meteorological conditions and / or forecasts, including wind conditions and / or forecasts for the first renewable power generation unit (EA1, 1RPGU) and solar conditions and / or forecasts from the second renewable power generation unit (EA2, 2RPGU).

12. The hybrid power plant according to claim 1, further comprising: - a module for deriving estimates of electrical losses in a hybrid power plant; - means for deriving a measure of electrical losses in the hybrid power plant based on the difference between the total power production from the plurality of energy assets and the power measurement at the point of common coupling (PoC), and a regulator arranged to apply the estimated values ​​of the electrical losses and the measured values ​​of the electrical losses in an active power control loop of a power plant controller, said active power control loop being arranged to control the active power production of the hybrid power plant at the point of common coupling, The regulator (300) is used to calculate the available power from the first renewable electricity generation unit (EA1, 1RPGU) and the second renewable electricity generation unit (EA2, 2RPGU).

13. The hybrid power plant according to claim 1, wherein: The second renewable electricity generation unit includes a plurality of solar power units (PV1, PV2).

14. The hybrid power plant according to claim 1, wherein: The energy storage unit (EA3, ESU) is a battery energy storage system (BES).

15. A method for controlling a hybrid power plant, the hybrid power plant being connected to an electric grid (1000) to produce electric power to the electric grid, the hybrid power plant comprising a plurality of energy assets, the plurality of energy assets (EA1, EA2, EA3) comprising: - a first renewable electricity generation unit (EA1, 1RPGU) comprising a plurality of wind turbine generators (WTG1, WTG2), - a second renewable electricity generating unit (EA2, 2RPGU), wherein the second renewable electricity generating unit is different from the first renewable electricity generating unit, and an energy storage unit (EA3, ESU) capable of storing energy from the first and second renewable electricity generation units and delivering electricity to the grid when needed, The method comprises: - controlling a power plant controller (PPC, 200) to communicate with a plurality of energy assets, said power plant controller being arranged to receive a real power reference (P_REF,ext, Prefhpp), - performing a first comparison (C1) of said active power reference (P_REF,ext, Prefhpp) with the available power (PavailPGS) from said first renewable power generating unit (EA1, 1RPGU) and said second renewable power generating unit (EA2, 2RPGU), - performing a second comparison (C2a, C2b) of the available charging or discharging capacity of the energy storage unit (EA3, ESU) with the first comparison and assigning a corresponding set point (PS_3, PrefESS) to the energy storage unit (EA3, ESU), and - in response to said first comparison (C1), allocating set points (PrefPGS, PS_1, PS2) to said first renewable electricity generation unit (EA1, 1RPGU) and to said second renewable electricity generation unit (EA2, 2RPGU), respectively, in order to deliver electricity from the hybrid power plant according to the received active power reference (P_REF,ext, Prefhpp), wherein, when the result of the first comparison of the active power reference (P_REF, ext, Prefhpp) with the available power (PavailPGS) is that the active power reference (P_REF, ext, Prefhpp) is greater than the available power (PavailPGS), thereby indicating a power shortage, the power plant controller (PPC, 200) is arranged to assign a set point (PrefPGS, PS_1, PS2) that is higher than the additionally indicated available power (PavailPGS) from the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU), respectively, to the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU).

16. A power plant controller (200) for controlling an associated hybrid power plant connected to an associated power grid (1000) to produce power to the power grid, the hybrid power plant comprising a plurality of energy assets, the plurality of energy assets (EA1, EA2, EA3) comprising: - a first renewable electricity generation unit (EA1, 1RPGU) comprising a plurality of wind turbine generators (WTG1, WTG2), - a second renewable electricity generating unit (EA2, 2RPGU), wherein the second renewable electricity generating unit is different from the first renewable electricity generating unit, and an energy storage unit (EA3, ESU) capable of storing energy from the first and second renewable electricity generation units and delivering electricity to the grid when needed, wherein a power plant controller (PPC, 200) is arranged to communicate with a plurality of energy assets, the power plant controller being arranged to receive an active power reference (P_REF,ext, Prefhpp) and to perform a first comparison of said active power reference (P_REF,ext, Prefhpp) with an available power (PavailPGS) from said first renewable power generating unit (EA1, 1RPGU) and said second renewable power generating unit (EA2, 2RPGU), and performing a second comparison of the available charging or discharging capacity of the energy storage unit (EA3, ESU) with the first comparison and assigning a corresponding set point (PS_3, PrefESS) to the energy storage unit (EA3, ESU), and The power plant controller (PPC, 200) is further arranged to distribute set points (PrefPGS, PS_1, PS2) to the first renewable power generating unit (EA1, 1RPGU) and the second renewable power generating unit (EA2, 2RPGU), respectively, in response to the first comparison, so as to deliver power from the hybrid power plant according to the received active power reference (P_REF,ext, Prefhpp), wherein, when the result of the first comparison of the active power reference (P_REF, ext, Prefhpp) with the available power (PavailPGS) is that the active power reference (P_REF, ext, Prefhpp) is greater than the available power (PavailPGS), thereby indicating a power shortage, the power plant controller (PPC, 200) is arranged to assign a set point (PrefPGS, PS_1, PS2) that is higher than the additionally indicated available power (PavailPGS) from the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU), respectively, to the first renewable power generation unit (EA1, 1RPGU) and the second renewable power generation unit (EA2, 2RPGU).

17. A computer program product adapted to enable a computer system to control a hybrid power plant according to any one of claims 1 to 14, the computer system comprising at least one computer having data storage means connected thereto.

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