Determining and using a flexibility capability for an electrical grid

Abstract

The invention relates to a method for determining a flexibility capability for a power grid (2) within a time range by means of an energy system (1) having a plurality of installations (11) which can be operated flexibly with respect to the generation and / or consumption processes carried out by the installations, wherein the energy system (1) comprises a central control device (12), with respect to the installations (11), for controlling the operation of the installations (11). The method is characterized in that current capability values of the installations (11) are detected and transmitted to the control device (12), the flexibility capability that can be provided being determined by the control device (12) by comparing the detected current capability values with reference data relating to a reference operation of the installations (11). The invention also relates to a method for operating an electrical grid by means of a grid operator (3).

Description

[0001] Description

[0002] Determination and use of flexibility capacity for an electricity grid

[0003] The invention relates to a method according to the preamble of claim 1 and a method according to the preamble of claim 13.

[0004] The transition to energy systems powered by renewable energy sources requires additional flexibility to respond to fluctuations in load and generation. This flexibility is traded, for example, on balancing power markets and can be accessed there by electricity grid operators.

[0005] However, participation in balancing power markets typically involves an entry threshold regarding the flexibility capacity provided. A minimum of 1 megawatt of capacity is usually required. This excludes smaller energy systems and their installations from participating in balancing power markets. Therefore, smaller energy systems can only participate in balancing power markets through pooling.

[0006] In the future, however, changes to grid regulations could make it possible to directly utilize the flexibility of smaller energy systems, particularly individual plants. Besides current regulatory barriers to entry, there are also technical challenges to integrating smaller energy systems and their components in this way.

[0007] The present invention is based on the objective of improving or making usable the flexibility of energy systems, in particular smaller energy systems, for the operation of a power grid.

[0008] The problem is solved by a method with the features of independent claim 1 and by a method with the features of independent claim 13. Advantageous embodiments and further developments of the invention are specified in the dependent claims.

[0009] The inventive method for determining flexibility power for a power grid within a time range by means of an energy system with several plants that can be operated flexibly with respect to their generation and / or consumption, wherein the energy system comprises a control device central to the plants for controlling the operation of the plants, is characterized in that current power values ​​of the plants are recorded and transmitted to the control device, wherein the control device determines the available flexibility power by means of a comparison of the recorded current power values ​​with reference data relating to a reference operation of the plants.

[0010] In this context, the term "control" includes "regulation." Therefore, the control device can also regulate the operation of the systems, if necessary.

[0011] According to the invention, the flexibility power is provided by the energy system or its components. This flexibility power can have different signs, with a feed-in of power / energy into the grid typically being characterized by a positive sign. A negative flexibility power thus corresponds to a feed-out, i.e., a consumption.

[0012] According to the invention, the control device is designed to determine the flexibility performance. This is done by comparing / aligning current performance values ​​of the systems with respective reference data. Flexibility can be determined by the difference between the recorded performance and a comparable operating point of the respective system and / or as a deviation from a reference operating point of the respective system.

[0013] The current performance values ​​are recorded, for example by the respective measuring devices of the systems. The measuring devices then transmit the recorded measured values ​​or the recorded performance values ​​to the control device.

[0014] The reference data can define a reference operating state for the respective systems. This reference data can include historical data and / or forecasts. Symbolically, the control device uses the reference data and the current performance values ​​of the systems to determine the likely flexibility of each system. The control device is designed as a central control unit for the systems, so that the flexibility or flexibility capacity is also determined centrally for all systems. This is particularly advantageous because a potential grid operator who wants to utilize the flexibility of the systems or the energy system for operating their electricity grid does not have to communicate with each system individually, but only with the central control unit.

[0015] The central and coordinated determination of the flexibility capacity of the energy system's plants by the central control device facilitates, in particular, the simplified integration of these plants into balancing power markets. This is especially true when the control device aggregates the individual flexibilities of the plants to determine the total flexibility capacity provided. However, the flexibility capacity can also be determined on a plant-by-plant basis. In principle, the control device determines the flexibility capacity of each plant.

[0016] Furthermore, costs for operating and expanding electricity grids are reduced, as flexibility can be specifically provided in areas with grid bottlenecks. In addition, local flexibility potentials from smaller energy systems can be utilized, which a grid operator can then use to operate its electricity grid. For this, the grid operator does not need to communicate with every single component of the energy system, but advantageously only with the central control unit.

[0017] The invention thus provides, in particular, a method for determining flexibility and, in one of its embodiments, for transmitting the determined flexibility to a network operator who can use it advantageously for the operation of his electricity network.

[0018] The inventive method for operating a power grid by a grid operator is characterized in that a flexibility power determined according to the invention and / or according to one of its embodiments is used in the operation of the power grid.

[0019] Similar, equivalent and equivalent advantages and / or embodiments of the inventive operating method result from the inventive method for determining flexibility.

[0020] According to an advantageous embodiment of the invention, the reference data includes historical data of the plants.

[0021] The historical data includes, in particular, historical performance values, for example, the performance value of a plant on a previous day and / or a comparable day at the same time or at a comparable time.

[0022] Alternatively or additionally to the historical data, the reference data can include forecasts, for example, forecasts of the generation output of a photovoltaic system, based, for instance, on weather forecasts, and / or forecasts of the charging and use of electric vehicles. In an advantageous embodiment of the invention, the historical data includes performance values ​​of the systems regarding their operation within one or more past days.

[0023] This allows flexibility or flexibility performance to be advantageously determined by a difference between the recorded current performance values ​​and the aforementioned past performance values.

[0024] In other words, according to an advantageous embodiment of the invention, the comparison is made by means of a deviation or difference between the recorded current performance values ​​and the performance values ​​of at least one previous day.

[0025] This allows for a more advantageous determination of flexibility or flexibility performance.

[0026] According to an advantageous embodiment of the invention, active power and / or reactive power of the systems are used as current performance values.

[0027] This advantageously provides active and reactive power as flexibility.

[0028] In an advantageous further development of the invention, the current performance values ​​are recorded by the respective control units of the systems.

[0029] In other words, the systems have individual control units that record the current power values ​​and transmit them to the central control device. In this sense, the control units also function as measuring units for recording the current power values. The control units can be calibrated or uncalibrated meters, as even simple measuring units are sufficient for recording the current power values. Furthermore, the measuring units or the control units can be virtual. If the systems do not have individual control units / measuring units, the current power values ​​can be determined or (virtually) calculated, in the simplest case, by a power balance, or, in a more complex case, by disaggregation.According to an advantageous embodiment of the invention, the reference data for the systems include reference performance values, wherein the comparison is made by means of a deviation of the recorded current performance values ​​from the reference performance values.

[0030] In other words, the respective, i.e., plant-specific, flexibility is determined by P Flex = P- e{ ~ Pi determined, where P ' ef the respective reference power value and P t This denotes the current performance value of the j-th system. Here, P is... t Positive for load / consumption and negative for power generation. The determined flexibility capacity is then divided by the individual capacities ( ?lex )i=i,..., w (plant dissolved) or the aggregated output P Flex = Zi=i,...,N ^ lextrained. Partial aggregation across a subset of the systems is also conceivable. For example, aggregation across comparable types of systems and / or redundant systems is advantageous. A network of redundant combined heat and power (CHP) plants, for instance, can provide such aggregated flexibility, that is, flexibility aggregated across the CHP plants.

[0031] In an advantageous further development of the invention, the flexibility performance is thus determined either broken down by plant or aggregated across the plants.

[0032] According to an advantageous embodiment of the invention, the determined flexibility performance is transmitted to a network operator of the electricity grid.

[0033] Advantageously, this allows the grid operator to utilize the flexibility provided by the plants or the energy system for the operation of its electricity grid. Advantageously, this does not require an interface between the grid operator and each individual plant. This is because the flexibility of the plants is determined centrally by the control device, which then transmits this information to the grid operator. Therefore, advantageously, only one communication interface between the control device and the grid operator, or a grid control unit of the grid operator, is required.

[0034] In an advantageous further development of the invention, a plant identification number (plant ID) is additionally transmitted to the network operator for one or more plants.

[0035] This has the advantage that the grid operator knows, at least for some of the plants, which plants provide which flexibility. In other words, the determined flexibility or flexibility capacity is transmitted to the grid operator, at least partially broken down by plant. Alternatively or additionally, the flexibility or flexibility capacity aggregated across several plants can be transmitted to the grid operator.

[0036] According to an advantageous embodiment of the invention, the determined flexibility performance is transmitted to a control power market of the electricity grid.

[0037] In this context, the network operator and the energy system or the control device advantageously communicate via a balancing power market, which coordinates the use of flexibility as balancing power.

[0038] In an advantageous further development of the invention, the energy system comprises at least one photovoltaic system, one electricity storage system, one heat pump, one electric heating element, one charging station and / or one combined heat and power plant as systems.

[0039] The aforementioned systems are particularly well-suited for providing flexibility or flexibility services.

[0040] Further advantages, features, and details of the invention will become apparent from the exemplary embodiments described below and from the drawing. The figure schematically shows one embodiment of the invention.

[0041] Similar, equivalent, or equivalent elements can be provided with the same reference symbols in the figure.

[0042] The figure shows an energy system 1 and a network operator 3 or an electricity grid 2.

[0043] Network operator 3 is trained to operate the electricity network 2, and network operator 3 includes in particular a network control device for this purpose.

[0044] Energy system 1 comprises several systems 11. In particular, energy system 1 includes a photovoltaic system, a battery storage system, a heat pump / HVAC system and other electrical consumers as systems 11.

[0045] Furthermore, the energy system 1 includes a central control device 12 for the systems 11. The control device 12 is designed to determine flexibility based on currently recorded power outputs or power values ​​of the systems 11 and respective reference data, either system-specific and / or aggregated at least partially or completely across the systems 11. The respective current power values ​​are recorded by the respective control units / measuring units of the respective systems 11 and transmitted to the control device 12.

[0046] Furthermore, the control device 12 is designed to transmit the determined flexibility or flexibility performance to the network operator 3 either as a system breakdown or at least partially aggregated across the systems.

[0047] Due to the anticipated simplification of the network guidelines, it can be assumed that calibrated meters will no longer be required for recording power values ​​in the future. This will allow installations 11, which are already equipped with a simple meter or a control / measuring unit, to transmit the power values ​​directly to the central control device 12. Furthermore, virtual meters can be used to record the current power values, i.e., for data acquisition. In the simplest case, in a system where all but one installation are measured, the power value of this missing installation can be calculated using a power balance. In more complex cases, algorithms for disaggregating time series can be used, for example.

[0048] A balancing power market can also be used as a communication interface between the grid operator 3 and the plants 11. Plants 11 and / or energy system 1 can register on this market and subsequently offer their flexibility. For this purpose, grid operator 3 can, for example, provide a web service that accepts the flexibility bids and then transmits the acceptances and rejections to the control device 12. Energy system 1 or control device 12 can submit multiple bids regarding the determined flexibility to the balancing power market. This is done, for example, as a list, with each entry including a plant identification number (plant ID), a period for providing flexibility, and the flexibility capacity determined by control device 12.

[0049] When using a balancing power market, the grid operator 3 can award a surcharge to individual plants 11 or to partially aggregated plants 11. These plants then report the flexibility provided during the delivery phase. This could, for example, be the active charging of an electric vehicle at a specific time and with a specific power output. In this case, the energy system 1 comprises several plants 11, so it is advantageous for the grid operator 3 and / or the balancing power market if the flexibility for the plants 11 is determined centrally by the control device 12 and also transmitted centrally to the grid operator 3 or the balancing power market by the control device 12. The activation of the flexibility is also centrally coordinated by the control device 12 for the plants 11.

[0050] In other words, the control device 12 is designed, for example, as an edge device or as a smart meter gateway.

[0051] The control device 12 requests the corresponding measured values, i.e., the respective current power values, in particular the respective active and / or reactive power, from the flexibly controllable systems 11 with temporal resolution. These measured values ​​can be provided by measuring units / control units of the respective systems 11 and transmitted to the control device 12.

[0052] The control device 12 now determines the available flexibility by comparing it with historical data, for example, data from the current day or from comparable past days, depending on the country-specific design of the network guidelines or the technical connection conditions. In this process, the control device 12 has no information about the agreed flexibility contracts. This is therefore independent of whether the flexibility is actually provided.

[0053] The flexibility or flexibility capacity determined by the control device 12 is assigned the respective plant ID for each individual plant 11 and / or partially aggregated and transmitted to the network operator 3. Therefore, two configurations are generally conceivable.

[0054] According to the first configuration, the provision (or maintenance) of flexibility for energy system 1 is provided in aggregate across all facilities 11.

[0055] According to the second configuration, the provision (or availability) of flexibility by energy system 1 is broken down by plant, meaning it is transmitted to network operator 3 along with the associated plant IDs. Furthermore, a combination of the two configurations mentioned is conceivable, in which the provision (or availability) of flexibility by energy system 1 is transmitted to network operator 3 partly broken down by plant and partly in aggregated form.

[0056] The flexibility provided by each plant 11 is determined by the control device 12. If the control device 12 has no details about agreed flexibility contracts, at least two calculation variants are possible.

[0057] Firstly, the flexibility provided can be determined by a change in the measured performance at a similar working point, for example as a difference in performance at the same time of the previous day.

[0058] On the other hand, flexibility can be determined by a deviation from a reference operation, for example, a heat-led operating mode of a CHP unit or a battery storage system for maximizing self-generated electricity.

[0059] Here, positive flexibility is characterized by an additional feed-in to the power grid 2. Accordingly, the control device 12 determines the flexibility of each j-th system 11 by F lex = P- e{ ~ Pi' where the power P t It is positive for loads and negative for power generators.

[0060] Although the invention has been illustrated and described in detail by the preferred embodiments, the invention is not limited by the disclosed examples, nor can other variations be derived from them by a person skilled in the art without leaving the scope of protection of the invention.

[0061] Reference symbol list

[0062] 1 Energy system

[0063] 2. Power grid 3. Network operator

[0064] 11 Annex

[0065] 12 Control device

Claims

Patent claims 1. Method for determining flexibility power for an electricity grid (2) within a time range by an energy system (1) with several plants (11) that can be operated flexibly with respect to their generation and / or consumption, wherein the energy system (1) comprises a central control device (12) with respect to the plants (11) for controlling the operation of the plants (11), characterized in that current power values ​​of the plants (11) are recorded and transmitted to the control device (12), wherein the control device (12) determines the available flexibility power by comparing the recorded current power values ​​with reference data relating to a reference operation of the plants (11).

2. Method according to claim 1, characterized in that the reference data comprise historical data of the plants (11).

3. Method according to claim 2, characterized in that the historical data comprise performance values ​​of the systems (11) with regard to their operation within one or more past days.

4. Method according to claim 3, characterized in that the comparison is made by means of a deviation between the recorded current performance values ​​and the performance values ​​of at least one previous day.

5. Method according to one of the preceding claims, characterized in that active power and / or reactive power of the systems (11) are used as current performance values.

6. Method according to one of the preceding claims, characterized in that the current performance values ​​are recorded by respective control units of the systems (11).

7. Method according to one of the preceding claims, characterized in that the reference data for the systems (11) include reference performance values, wherein the comparison is made by means of a deviation of the recorded current performance values ​​from the reference performance values.

8. Method according to one of the preceding claims, characterized in that the flexibility performance is determined either on a plant-by-plant basis or aggregated across the plants (11).

9. Method according to one of the preceding claims, characterized in that the determined flexibility performance is transmitted to a network operator (3) of the electricity network (2).

10. Method according to claim 9, characterized in that, in addition, a plant identification number is transmitted to the network operator (3) for one or more plants (11).

11. Method according to one of the preceding claims, characterized in that the determined flexibility power is transmitted to a control power market of the electricity grid (2).

12. Method according to one of the preceding claims, characterized in that the energy system (1) comprises at least one photovoltaic system, one electricity storage system, one heat pump, one electric heating element, one charging station and / or one combined heat and power plant as systems (11).

13. Method for operating an electricity grid by a grid operator (3), characterized in that a flexibility power determined according to one of the preceding claims is used in the operation of the electricity grid (2).

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