Methods for providing reserve capacity to stabilize the power grid and / or provide energy market products

Abstract

The present invention relates to a method for providing reserve power for stabilizing a power grid (N) and / or providing an energy market product using a plurality of building batteries (B), wherein the building batteries are each connected to the power grid (N) via a grid connection point (P), and the building batteries are each grouped together with other power units (TE1...TEm) in a building distribution network (G1...Gn) defined by the grid connection points (P), and at least one low-speed power unit (BEV) is present in the plurality of building distribution networks (G1...Gn), and the low-speed power unit requires a latency of more than 2 seconds for a significant change in power throughput, and the method The method includes the steps of: (M1) identifying a grid frequency deviation in the grid (N) and / or a demand signal for an energy market commodity; (M2) aggregating a first group of building batteries (B) corresponding to a first group of building wiring networks; (M3) activating a second group of building batteries (B) from the first group of building batteries corresponding to a second group of building wiring networks; and (M4) providing the required reserve power by the group of building batteries (B) to offset the determined grid frequency deviation and / or to provide the required energy market commodity. The method is characterized by a method step (M5) using a plurality of low-speed technology power units (BEVs) in the second group of building wiring networks to change the power throughput so as to take over at least a portion of the building batteries from the second group of building batteries (B) when providing the required power.

Description

[Technical Field]

[0001] The present invention relates to a method for providing electrical reserve power for stabilizing an electrical grid and / or providing an energy market product. [Background technology]

[0002] A building battery is a battery with secondary cells that is installed in the electrical building network of a residential or industrial enterprise and can, among other functions, supply electricity to the electrical devices (power consumers) present there as needed. Specifically, such power units in the form of batteries can be usefully used together with power units in the form of renewable generators, such as photovoltaic systems installed in buildings, for example, to support the energy transition. They are connected to the public power grid of the grid operator, so they can receive grid-serving electrical power from the grid as a so-called negative reserve and, if necessary, can also supply grid-serving power to the grid as a so-called positive reserve to stabilize the grid. The described adaptive capacity can also be traded on the energy market, as can the offering of other energy market products.

[0003] From the perspective of grid operators, so-called reserve units, also known synonymously as technical units, typically have a high power supply capacity to provide reserves, allowing them to release or absorb negative and / or positive reserves. Specifically, reserves within the meaning of this invention refer to primary reserves, also known today in German terminology as FCR (frequency control reserve), or secondary reserves, also known today in German terminology as aFRR (automatic frequency recovery reserve), which can output or absorb in the range of several tens of megawatts. Traditionally, these are, for example, individual hydroelectric or thermal power plants for generating electrical energy, whose output is correspondingly increased or decreased to provide the desired positive or negative reserve. In addition to primary and secondary reserves, there is also reserve in the form of so-called inertial reserves, which, due to their upstream latency, typically compensate for frequency fluctuations from 0 to 30 seconds via the torque of heavy generating turbines. The fact that building batteries can be controlled to output or consume power at sufficiently high speeds makes it possible to provide so-called inertial reserves via aggregated building batteries. However, the provision of inertial reserves has not yet been implemented in the general energy market. It is still limited to downstream reserve types, specifically primary and secondary reserves. In the future, it is quite likely that the provision of reserves in the time frame of inertial reserves will also be open to energy market trading. In any case, within the scope of the present invention, inertial reserves are also included in the concept of providing reserves.

[0004] Within the scope of the present invention, the technical terms standby unit or, equivalently, technical unit, are defined much narrower than usual. This means that a standby unit in the sense of the present invention already exists, for example, in the form of an individual building battery or even in the form of an individual building with its associated internal wiring network. In the case of a standby unit as an individual building, this more precisely means that the standby unit may also be defined as the totality of everything that consumes and / or generates electrical energy, and the power flow between this standby unit and the external power grid can be detected via a common grid connection point with an ammeter unit.

[0005] Within the scope of the present invention, the various electrical energy consumers and electrical energy generators are generally referred to as power units, which consist of power consumption units, power output units and mixed power consumption / output units, which are - Electrical loads as power consumption units, technically suitable only for power consumption - an energy storage device as an energy storage unit, technically suitable for both energy consumption and energy output; - A generator as an electrical power generating device, technically suitable only for electrical power output is selected from the group comprising:

[0006] Thus, according to this broad definition, at least one, but usually several, such above-defined power units are placed in a building wiring network defined via a network connection point.

[0007] The power units of the auxiliary units represented by the building distribution network, which are usually present in a plurality of units in the building distribution network, are divided into two groups within the meaning of the present invention according to their individual power consumption / output capacity: If the power input / output capacity is equal to or greater than 2 kilowatts, these power units are hereinafter referred to as high-power units.

[0008] In relation to the building grid, high-power units are, for example, photovoltaic systems with correspondingly high power, building batteries with correspondingly large capacity, air conditioning systems and appliances, heat pumps, thermal energy storage devices, charging connection units for electric vehicles, ovens and electric water heaters. In the building grid of industrial enterprises, numerous industrial plants and machines with a power consumption of more than 2 kilowatts also form part of the high-power unit category. High-power units in the form of small commercial or domestic combined heat and power plants with integrated generators can also be integrated into the building grid.

[0009] Within the scope of the present invention, there is a subgroup of high-power units that should be referred to as dispatchable high-power units. The term dispatchability here refers to the possibility of delaying the switch-on or switch-off time of a high-power unit, thereby dispatching its power consumption or power output over time, without significantly affecting the comfort of one or more users of the power unit in the building's distribution network. This delay is usually in the range of several minutes. When a user connects an electric vehicle to a charging point in the building's distribution network to charge, even if the charging process starts with a delay of several tens of minutes or even several hours, this is not a problem for the user, given that several hours of parking time (in residential garages, overnight) is regularly available. The same applies to heat pumps or thermal energy storage systems. Considering that the complete charging and discharging process usually takes several hours, such time delays in the range of several minutes or hours can be tolerated by the user without significantly affecting the operational comfort of the building management. These high power units can therefore be scheduled within a certain time frame regarding their power behavior and are hereafter referred to as dispatchable high power units.

[0010] This is different for high power units, for example in the form of air conditioning units and appliances, appliances for boiling water, or household appliances such as ovens. Users of these high power units expect functionality to be immediate. They cannot and do not want to wait 5 to 10 minutes to get cooled air and / or warm water, or for the household appliance to perform a desired task.

[0011] Therefore, the boundary between dispatchable and non-dispatchable power units is subjective and depends on the specific user's practices. However, it is possible to predict with a high degree of certainty from a statistical average which high power units will be classified as dispatchable and which will be classified as non-dispatchable, primarily from the user's perspective, over a time frame of up to 10 minutes or even hours.

[0012] If the power input / output capacity of a power unit in a building's distribution network is less than 2 kilowatts, then this power unit is hereinafter referred to as a small power unit. This includes all power consumers in the building's distribution network, specifically all lighting, all household appliances consuming less than 2 kilowatts, such as most vacuum cleaners, water heaters, refrigerators and freezers, washing machines, irons, all types of household appliances, computers, etc. The cumulative consumption of these small power units is recorded under a statistical standard load characteristic curve.

[0013] It should be emphasized that the concept of a building distribution network, which defines a certain number of power units in the building distribution network via a common connection point, does not imply that all power units must be located inside any building of any type. Power units that must be or are usually located outdoors are, for example, photovoltaic, hydroelectric, or wind energy systems. Similarly, power units designed for lighting or, for example, lawnmower robots, can be permanently located outdoors. These power units are also assigned to the building distribution network by a common network connection point. For spare units, it is also possible that the associated network connection point and the power units connected via this network connection point do not have any building. The only determining factor is the common network connection point, which defines the number of power units recorded in the connected power network. For simplicity, this power network is called a building distribution network because, in most cases, the ammeter unit, which is also necessary for the network connection point, is not located outdoors but is protected from weather conditions inside the building. The building may be very small and in the extreme case may only contain an ammeter unit in the form of a meter connection column, with all power units in the building's distribution network being located outside the ammeter connection column.

[0014] In order to be able to use a uniform term for the power consumption and power output by power units within the scope of the present invention, the term power throughput will be used below. Thus, a change in the power throughput of a power unit means both a change in power consumption and a change in power output. The concept of providing a reserve also encompasses both the process of receiving power from the power grid (negative reserve) and the process of supplying power to the power grid (positive reserve).

[0015] Each grid-related and / or energy market product-related change in power throughput occurs during a certain latency period. In the present patent application, the term latency is understood to mean the period from the provision of an electrical switching command to the stored measurement of the result of the switching command. Such a switching command relates to a change in the respective power throughput in the sense of the above definition relative to a characteristic power throughput for all power units equipped with said building energy storage device in the form of a building battery.

[0016] In a plurality of building distribution networks, there is at least one power unit for which a significant change in power throughput requires a latency time of more than 2 seconds. This type of power unit is hereinafter referred to as a slow power unit. Within the scope of the present invention, a change in power throughput is considered significant if it is greater than 25%.

[0017] Grid operators need something to provide positive and / or negative reserves to stabilize grid frequency. Whether it's positive reserves and / or negative reserves, Frequency control reserve (FCR = primary reserve) Automatic Frequency Recovery Reserve (aFRR = secondary reserve), or Manual Frequency Recovery Reserve (mFRR = Tertiary Frequency Recovery Reserve) It is in the form of:

[0018] A method for providing reserve power is known from EP 4000155 A1. This is done using a number of building batteries, each connected to the power grid via a grid connection point. These building batteries are each grouped with further power units in a building grid defined by the grid connection points. In the present invention, all power units connected to the building grid are also considered and referred to as technical units. Each power unit, insofar as it has such functionality, can receive power from the building grid and, with appropriate control, can also receive power from the power grid and / or feed power into the power grid in the same way. A building battery constructed from secondary batteries is therefore a component of such a power unit.

[0019] A method known from EP 4000155 A1 for providing reserves for stabilizing the power grid and / or for providing energy market products comprises the following steps. - identifying a grid frequency deviation in the grid and / or a demand signal for an energy market product Clustering a first group of building batteries corresponding to a first group of building wiring networks. activating a second group of building batteries corresponding to a second group of building wiring networks from the first group of building batteries; and providing a required reserve capacity, specifically by the group of building batteries, to offset the determined grid frequency deviation and / or providing a requested energy market product, specifically by the group of building batteries.

[0020] The order of the first three mentioned process steps is variable. It is important to note that the first mentioned method step of identifying the grid frequency deviation in the grid and / or the demand signal for energy market products can be performed both before and after, as well as simultaneously with or between, the above mentioned method step of clustering and commissioning the building batteries. Once the provision of reserve power begins, the grid frequency deviation is repeatedly determined, whereby the deviation is minimized by other method steps, and the grid frequency is controlled in dynamic equilibrium towards the smallest possible fluctuations around the ideal 50.0 Hz.

[0021] In addition to building batteries, EP 4000155 also uses other large power units and the aggregation of small power units for grid-related and / or energy market-related power throughput. [Prior art documents] [Patent documents]

[0022] [Patent Document 1] European Patent Application Publication No. 4000155 Summary of the Invention [Problem to be solved by the invention]

[0023] Against this background, the object of the present invention is to further improve the interaction of various power units for the reliable provision of reserves and / or for the provision of energy market products. [Means for solving the problem]

[0024] This object is achieved by a method having the features of claim 1.

[0025] According to the present invention, the method comprises: and using a plurality of low-speed power units in a second group of the building distribution network to take over at least a portion of the building batteries from the second group of the building batteries by varying their power throughput when providing the required power.

[0026] Energy storage devices in the form of rechargeable building batteries have a relatively short latency period of less than two seconds for changing power throughput with an impact on the grid to which they are connected via a connection point. Therefore, they are particularly suitable for providing a primary reserve (FCR), which requires the grid to be relatively quickly available. The short latency period therefore allows a second group of clustered building batteries to be activated and provide the required power throughput first in time. Simultaneously, or with some delay, low-speed power units, which have a much longer latency period compared to the building batteries, are used. Depending on their functional configuration, the use of low-speed power units can result in increased power consumption from the grid, decreased power consumption, increased power output to the grid, or decreased power output.

[0027] As already mentioned in the introduction to the description, the order of the first three method steps (determining the grid frequency deviation, clustering the building batteries, and activating the building batteries) can be arbitrary. In particular, the provision of primary reserve power shall occur within a maximum of 30 seconds according to the grid operator's current specifications. Therefore, the method steps of clustering and activating the building batteries are usually already completed or already in progress when the grid frequency deviation is determined. This is because clustering and activation also take a few seconds or less, depending on the algorithms and communication networks used. The process of clustering the building batteries and / or activating them may be updated periodically or may occur continuously. In the clustering method step, the algorithms used preferably perform various optimizations. These may be adapted for operational management purposes, sustainability-related purposes, and / or other purposes.

[0028] To be traded on the energy market, suitable building batteries for a desired range of reserves and / or energy market products are typically grouped together by a control system, which specifically refers to identifying this subset of building batteries, referred to as a first group, thus forming the suitable building batteries that are kept ready to provide reserves and / or energy market products.

[0029] The step of activating a second group of building batteries from the first group of building batteries can involve either including all of the building batteries in the first group (and the first group strictly corresponding in quantity to the second group) or forming the second group as a subset of the first group. The method step of activating the second group does not yet imply the provision of power. Rather, process parameters are transmitted to at least the second group of building batteries, defining when and to what extent these building batteries will change their power throughput in response to a trigger signal to provide reserve capacity and / or energy market products. The method step of providing power is realized only by the triggered change in the power throughput of the triggered power units. The method parameter used is a grid frequency deviation threshold above or below which the grouped and activated building batteries and low-speed technology power units intervene in the method by changing their power throughput.

[0030] The transmitted thresholds for activation may be used uniformly for all building batteries or non-uniformly for different subgroups of building batteries. Whether a uniform or non-uniform threshold distribution exists, all building batteries are equally active; however, they differ from each other by different thresholds. The different thresholds affect when building batteries are triggered to change their power throughput to provide reserves and / or energy market products.

[0031] The trigger signal may be sent in particular by a control device located in the building grid, for example by an energy flow control device present there, when a local measurement in the building grid exceeds or falls below a grid frequency deviation threshold set for activating a building battery or other power unit. In the same scenario, this signal may also be sent by a centralized control device. Alternatively, the trigger signal may be sent directly from the centralized control device without a threshold comparison being performed.

[0032] In addition to the building batteries, the method step of clustering and / or the method step of putting into operation preferably also include low-speed power units, as long as they are present in the building grid of the first group or the second group, respectively. This means that the low-speed technology power units are also clustered together with the building batteries in the first group from the beginning and put into operation entirely in the second group or as a subset of the first group. However, due to the significantly longer latency time compared to the building batteries and the higher grid frequency deviation threshold, the provision of the changed power throughput is delayed or occurs at a later time when the higher grid frequency deviation threshold is exceeded.

[0033] Preferably, the determination of the grid frequency deviation occurs locally in all or a majority of the centralized building networks, and a local building network controller triggers activation of the building battery and / or the low-speed power unit if activation exceeds a predetermined grid frequency deviation threshold amount. Compared to centralized control, such a decentralized control system is more resistant to external attempts at manipulation in the form of cyber attacks.

[0034] Preferably, the replacement of the building battery during the provision of the required power occurs by a low-speed power unit from the same building wiring network to which the building battery is connected. In this way, from the perspective of the power grid, the takeover of the power supply of the building battery by the low-speed power unit occurs behind the same grid connection point in the same building wiring network. This makes control and regulation easier when there is a clear spatial separation in the power grid between the building battery to be replaced and the low-speed power unit used.

[0035] A preferred development of this method is to use a slow power unit and for the takeover of the building battery during the provision of the required power by the slow power unit used during the provision of the required power to occur permanently or periodically.Furthermore, if the grouping and activation of the building battery to provide the required power occurs permanently or periodically, it is advantageous that in the process the newly activated building battery also replaces the activated building battery that is already used to provide power when providing the required power.

[0036] When there is access to a large number of building distribution networks with various building batteries and other power units, including slow ones with relatively long latency times, it is advantageous to activate and use these power units for short periods of time, in the range of a few minutes, to provide the required power, and then replace them. However, this still means that the changeover occurs within a few minutes after their expiration date. As a result, previously activated and used power units are completely or partially replaced, and the replacement power units are used, so that they contribute to the production of the required power. It is advantageous if not all activated and used power units are replaced by new power units at the same time. Rather, the handover occurs one after another, so that activated and used power units are generally constantly coming in and out. In terms of the total number of activated and used power units, these handovers occur constantly. At the level of individual power units, the handover occurs periodically, and the period used for this does not need to be constant. It can be adjusted taking into account the system requirements to be met.

[0037] Particularly preferably, the method is designed to use multiple low-speed power units in the form of battery electric vehicles with EV batteries. Many EV batteries have an energy capacity roughly ten times that of building batteries. However, in the present invention, they are among the low-speed power units with a relatively high latency. This is particularly due to battery electric vehicle manufacturers. They often use proprietary control and regulation systems for EV battery charging management, which third parties can only use to a limited extent and usually cannot modify. In principle, EV batteries are both high-speed and low-speed power units within the meaning of the definition of the present invention given in the introduction to the description. However, their power supply capacity can be used to provide the required power by interacting with the high-speed building batteries.

[0038] An advantageous further development of this method using battery electric vehicles is characterized in that, in the case of battery electric vehicles, the charging current is monitored for a drop in the charging current in a specific manner, such that the achievement of full charge of the associated EV battery is characterized as an event, and in response to determining such an event, the associated battery electric vehicle, if it contributed to the achievement of the required power until the determined event, is replaced by another power unit, or the associated battery electric vehicle is characterized as not currently available for absorbing power. In this way, it is ensured that the low-speed power unit contributing to the required power is replaced in the short term by a building battery or another power unit in the same building wiring network, or alternatively by a building battery or other power unit located in each case in another building wiring network.

[0039] It is particularly preferred that a battery electric vehicle contribute to the production of required electricity not by outputting power from the EV battery to the grid, but only by consuming power to charge the EV battery and / or by not consuming power to charge the EV battery. This means that the EV batteries of a battery electric vehicle are charged only in one direction. From the perspective of the grid, they then represent a relatively high-load, high-power unit. This does not pose any measurement difficulties, and it would certainly prevent, for example, the supply of locally generated green electricity, which previously charged the EV battery, to the grid. Most EV batteries currently installed in battery electric vehicles, when they are always discharged in bidirectional operation toward the grid, have a cycle life that is insufficient compared to the expected vehicle life. If the cycle life becomes sufficiently long in the future, the method according to the present invention could also be implemented in bidirectional operation of battery electric vehicles.

[0040] To provide power by unidirectional use of EV batteries, it is advantageously provided that a certain number of battery electric vehicles in operation to be charged from the power grid is determined and formed, a maximum possible power consumption from the power grid is defined by this number of vehicles in operation, and an average power consumption of the battery electric vehicles in the number of vehicles in operation, which is in the range of 40% to 60% of the maximum possible power consumption, in the absence of significant power grid frequency fluctuations and / or unmet demand for energy market products, is set as an operating point by the number of battery electric vehicles in operation. For this purpose, each EV battery belonging to the number of battery electric vehicles in operation to be charged from the power grid is: - No electricity consumption from the grid - the maximum possible consumption of electricity from the grid, and - Power consumption between 0% and 100% of the maximum possible power consumption from the grid In this way, an operating point for the EV batteries can be set, and when needed, power for reserves and / or energy market products to stabilize the grid is provided from the EV batteries. The crucial factor here is that the operating point can be constructed in such a way that this charging or non-charging behavior can be predicted over a short period of time (minutes) for at least some of the EV batteries. This depends, for example, on economic aspects such as whether non-charging EV batteries are available for charging, whether only EV batteries that are already charging can be switched off, or whether some or all of the batteries can be charged with a lower charging current, or a more or less balanced approach between charging and non-charging batteries can be chosen. It is important that the method according to the invention can predict the future for at least 90 seconds and control this state. Preferably, the method therefore provides that the predicted maximum possible power consumption of the number of EV batteries is guaranteed for at least 90 seconds into the future. "Severe" means a grid frequency fluctuation in the sense of the present invention, which, from the perspective of the grid operator, requires the use of reserves, preferably primary reserves.

[0041] The above statements also apply to using an EV battery in a bidirectional charging mode. The fact that energy from the EV battery can also be supplied to the grid during bidirectional charging increases the performance margin for providing reserve power. In the present invention, providing reserve power includes both absorbing electrical energy from the grid and supplying electrical energy to the grid. However, from the perspective of the grid, this levy can also be achieved by reducing the absorption of electrical energy. In a bidirectional charging mode for an EV battery, energy consumption can be reduced to "below zero" by supplying energy to the grid.

[0042] With regard to battery electric vehicle use, the method described above involves, for a certified battery electric vehicle, determining whether the current state of charge of each EV battery, whose total charge capacity is known in advance, is determined by the following analysis steps that precede in time the preceding charging process, namely: - Steps to save the date and time when EV battery charging started - determining and storing the amount of energy consumed and the charging time required for this; and - determining the state of charge of the EV battery at the time of the start of charging by subtracting the determined amount of absorbed energy from the pre-known total charge capacity, under the condition that the charging process is terminated without external intervention and thus a full charge of the EV battery is presumed. This procedure is advantageous because many manufacturers of battery electric vehicles do not allow easy data access to parameters such as the vehicle's State of Charge (SoC) to third parties. In order to be independent of these manufacturers, the evaluation method described above represents a practical approach to retrospectively determine the vehicle's State of Charge, and thus to be able to look ahead and make correct predictions in the future.

[0043] In a further development of this statistical evaluation, the method advantageously comprises performing a statistical analysis of user behavior of a certified battery electric vehicle (BEV) dependent on the day of the week and time of day from multiple charging processes analyzed in this manner to determine the state of charge of the EV battery, including an error value and an estimated charging time duration dependent only on the date and time of charging initiation. When the statistical analysis is performed on a sufficient number of charging processes, user-specific statistics are obtained that allow for a prediction of the current state of charge dependent only on the time of day and date. This should be related to the user's habits. Due to recurring events in the world of work and leisure, users often have periodic travel needs, which are often repeated weekly, for example. Even if the periodicity is monthly or daily rather than weekly, this type of statistical evaluation allows for a high probability of predicting the current state of charge and the user's charging preferences. Even if the prediction is incorrect, it is not a major problem; this one EV battery is just one out of hundreds. If the prediction is correct for the majority of EV batteries, this probability can be used to plan and operate the method. Finally, the EV battery's "fully charged" status can also be signaled by the disappearance of charging current. This can be used for on-the-spot replacement of building batteries from the reserve pool of a continuously recalculated selection list, as well as building batteries combined with EV batteries and / or other technological units from the building grid. Additionally, the composition of clustered and activated building batteries and low-speed power units is periodically recalculated and optimized. The use of building batteries, and in preferred cases, EV batteries, to provide the required power throughput is preferably implemented for only a few minutes. After that, the building batteries and EV batteries are replaced by those that had not been used previously but were prioritized on the constantly recalculated selection list. The purpose of this is to avoid a situation where multiple EV batteries unexpectedly finish their charging process at the same time and have to be replaced. The necessary takeover process for all types of power units is established in this way.

[0044] The above-mentioned method for statistical analysis is further advantageously designed so that the step of analyzing the charging process and / or the statistical analysis of the charging process is performed locally in the energy flow control device of the building wiring network and the results determined therefrom are stored locally. This feature means that knowledge of the user-specific consumption profile is localized in the building wiring network. If data communication with the centrally organized control unit is poor or disrupted, the energy flow control device in the building wiring network can continue to operate fully or at least partially autonomously for a certain period of time using the user profile stored therein.

[0045] Furthermore, the method is advantageously developed with respect to statistical analysis, such that the state of charge of the EV batteries and the estimated charging time length are used as the result of a statistical analysis of user behavior depending on the day of the week and the time of day to determine an operating point for the provision of required power by a certain number of battery electric vehicles in operation. The total EV battery power throughput for a future period can be predicted from the sum over all determined user-specific statistics together with the associated error. The total EV battery power throughput represents the EV battery's contribution to the power to be provided, and the associated error determines the necessary reserve that must be maintained to be able to guarantee the required power despite the deviation.

[0046] A further advantageous development of the method is characterized in that statistically determined parameters, such as the state of charge of the EV battery and the estimated charging time, are completely or partially replaced by specific queries of these parameters from authorized users of the battery electric vehicle. The required queries are made by the user via a digital terminal. Using these, the user can specify what state of charge the EV battery belonging to the vehicle should have at some future time. Based on the input within the query, the user also provides consent for the battery electric vehicle to be used within the defined framework for the method according to the present invention. Along with the queried vehicle's state of charge, which may alternatively be determined as an estimate from a statistical user-specific analysis, the earliest time that charging can begin and the latest time that charging must begin can be determined for each battery electric vehicle. The algorithm then distributes the determined charging times for each battery electric vehicle approximately uniformly. Furthermore, the algorithm plans the operating point formed by the entire EV battery over a specific time interval, for example, four hours, eight hours, or more. This corresponds to the currently important period required by the German grid operator for the provision of reserve power. However, there is discussion of shortening these periods to less than 60 minutes. Various incentives, particularly financial incentives, are offered to users to encourage them to provide information.

[0047] In addition, there are considerable economic benefits from the simple implementation of operating point planning, since the evening peak charging that grid operators fear is already avoided by the simple planning of operating points. This also applies if no reserves or energy services are currently provided.

[0048] For all methods described above, it is further preferred that the slow technology units are only used above a defined grid frequency deviation threshold. The slow technology units may be selected such that their inclusion either tolerates longer latency times (e.g., for grid frequency deviations greater than 50 mHz, preferably greater than 100 mHz), utilizes slow TE for rare events, or otherwise directs excess energy from the grid directly to the EV's battery by frequent charging in the negative range, in which the charging process is controlled asymmetrically.

[0049] Further features and advantages of the method according to the invention are shown in connection with the following described figures of exemplary embodiments. [Brief explanation of the drawings]

[0050] [Figure 1] 1 is a schematic diagram for a comprehensive explanation of the working principle of the method according to the invention; [Figure 2] 1 is a schematic diagram of the use of primary reserve to stabilize the grid frequency of a power grid over time. [Figure 3] FIG. 3 is an enlarged view of the time section marked III in FIG. 2. DETAILED DESCRIPTION OF THE INVENTION

[0051] FIG. 1 shows a schematic diagram of components used for the method according to the present invention for providing reserves for stabilizing a power grid N and / or for providing energy market products. Each of the buildings shown comprises a plurality of power units, acting as reserve units RE1, RE2, ... REn, in its respective building distribution network G, which is connected to the power grid N in a defined manner via an associated network connection point P. The reserve unit RE1 is shown enlarged in FIG. 1 as an example and illustrates several power units in the building distribution network G1. Meanwhile, this plurality of power units TE1, TE2, ... TEm, also referred to as technical units, consists of a group of large power units, each with a power throughput of 2 kilowatts or more. On the other hand, so-called small power units are present in the building distribution network G1 of the reserve unit RE1. Each of these has a power throughput of less than 2 kilowatts.

[0052] Furthermore, the power units TE1, TE2...TEm may have different latency times. In the present invention, a power unit is considered slow if it has a latency time longer than 2 seconds to achieve a significant change in power throughput. Please refer to the explanation in the introduction to the description for the definitions of latency period, power throughput, and a "significant" change in power throughput.

[0053] Each of the standby units RE1, RE2...REn has a large power unit in the form of a building battery B and a power unit in the form of an energy generator PV in the building grid. These power units are shown separately as components of the respective building grid, in addition to other power units in the form of technological units TE1, TE2...TEm. The PV energy generation systems preferably obtain renewable energy and are usually formed by photovoltaic systems. However, in particular wind power plants, hydroelectric power plants, biogas power plants with combined heat and power plants, fuel cells, emergency power units and combinations of these energy generators are also possible.

[0054] Furthermore, in each of the building networks G1, G2...Gn, an energy flow control device EFS is configured and designed to control and regulate the energy flows between the energy generating devices PV, the technological units TE1, TE2...TEm, the building battery B and the grid N in a cost-optimizing manner in accordance with instructions and to the benefit of the users / owners of the building networks N.

[0055] Many of the spare units RE1, RE2...REn have at least one so-called "low speed" high power unit BEV in the building distribution network G1, G2...Gn, which has a latency longer than 2 seconds to realize a significant change in power throughput, including a change in power throughput of more than 25%.

[0056] Furthermore, the building distribution network G of the spare unit RE1 is connected to the grid operator's power grid N via a smart meter SM and an associated smart meter gateway SMGW, which must be certified in accordance with the provisions of the Federal Office for Information Security (BSI) applicable in Germany. As an alternative to the connection of the building distribution networks G1, G2...Gn via a smart meter SM and an associated smart meter gateway SMGW, any form of electricity recording that supports direct commercialization via the grid N is also suitable.

[0057] For the further spare unit RE2, a detailed representation corresponding to the first spare unit RE1 shows the building wiring network G2 with the power units TE1 to TEm, the building battery B, the energy generating device PV and the energy flow control device EFS accordingly.

[0058] A further connection is established, e.g., a connection of the spare unit RE1 to the Internet 1 via a DSL line. In practice, preferably about 500 to 1000 such spare units RE1, RE2, ... REn exchange packet-switched data with the control system S via their respective connections to the Internet 1. The control system S forms a data gateway between the Internet 1 and the grid operator's process network 2. So-called customer premises equipment (CPE) is located within the process network 2. From the perspective of the grid operator's process network 2, the large number of clustered spare units RE1, RE2, ... REn applied to the control system S behaves like a large spare unit in terms of power, which is called a spare unit RG. Previously, the term "virtual technology unit" was used to describe such a spare unit RG. This spare unit RG may operate on the side of the process network 2 as a virtual power plant (VPP), for example, to provide the grid operator with reserve power for frequency stabilization of the grid N and / or to provide energy market products via the grid N. The transition from the domain of the Internet 1 to the domain of the grid operator's particularly secure process network 2 is achieved by a disconnection of the hardware medium in the control system S. This is realized by the use of a serial interface between the incoming and outgoing packet-switched data communication, visualized purely diagrammatically by the double arrow.

[0059] A preferred variant of the method described here by way of example provides for the implementation of method step M1, with respect to the scenario shown in Figure 1, of the determination M1 of the grid frequency deviation of the grid N and / or of the demand signal for the energy market product. This determination can be implemented both centrally by the control system S and / or locally by each standby unit.

[0060] Further method steps are in the form of clustering M2 of a first group of building batteries corresponding to a first group of building wiring networks and activating M3 a second group of building batteries B selected from the first group of building wiring networks. This second group is a subset or the entire set of existing spare units RE1 to REn. Each of these spare units has a building battery B, which can behave as a high-power unit on the power grid N with a latency time of no longer than 2 seconds. Therefore, the activation method step M3 occurs within this latency time. The method step M1 of identifying the power grid frequency deviation can occur before, between, during, or after the method steps of clustering M2 and activating M3 of the building batteries B. Additionally, the clustering and activation of the building batteries preferably occurs concomitantly with the clustering and activation of the low-speed power units BEV.

[0061] As a further method step M4, the provision of required power by the second group of building batteries B occurs in order to compensate the determined grid frequency deviation by means of reserve power and / or to provide the required energy market product.

[0062] A further method step consists of using a plurality of low-speed power units BEV in the second group of the building wiring network to vary their power throughput in order to take over at least a portion of the building batteries from the second group of building batteries B when providing the required power (M5).

[0063] Thus, initially a high-speed power unit in the form of a building battery B intervenes and is subsequently replaced completely or partially by a low-speed power unit. In this way, the amount of variation in power throughput used for reserves and / or energy market products can be significantly increased.

[0064] In a preferred variant of the method, a scenario is described below in which the low-speed power units BEV are in each case high-power units in the form of battery electric vehicles with an EV battery, which are connected to the respective building wiring networks G1...Gn via charging devices.

[0065] Even though in principle there is the possibility of bidirectional charging of these EV batteries, i.e. the EV battery of the battery electric vehicle BEV supplies energy to the power grid N, only unidirectional charging scenarios are preferably considered, i.e. the EV battery only absorbs energy from the power grid N, i.e. does not supply its own electrical energy to the power grid N at any time.

[0066] Figure 2 shows the power grid frequency f of power grid N over time t. G To stabilize the primary reserve power P FCR The time axis t is shown horizontally. The primary reserve P between a positive primary reserve of +2 MW and a negative primary reserve of -2 MW is FCR is plotted vertically on the right side of the figure, and the grid frequency f between 49.8 Hz and 50.2 Hz G is plotted on the left side of the figure. If the grid frequency were exactly 50.0 Hz, the use of reserve would be unnecessary. However, due to system dynamics, this is not a permanent stable state for grid N. Rather, a state of dynamic equilibrium must be achieved with the help of primary reserve. The solid line shows the grid frequency curve, which oscillates around the desired ideal 50.0 Hz. This frequency curve follows the dashed reserve curve, with a time offset of approximately 2 seconds, which is achieved in the grid frequency band between 50.1 Hz and 49.9 Hz, solely through the use of building battery B to provide primary reserve.

[0067] If the grid frequency deviates by more than 0.1 Hz, in addition to the building battery B, a low-speed high-power unit in the form of an EV battery of a battery electric vehicle BEV is also used to provide the required primary reserve. In addition, the magnitude of the grid frequency deviation, at which the low-speed high-power unit is also used to provide the primary reserve and thus subsequently also for the grid, is selected as 0.1 Hz in this exemplary embodiment. However, this threshold may be above or below this value and may be adapted to the respective situation.

[0068] 3 shows the expanded time portion marked III in FIG. 2, in which in addition to the building battery B, a battery electric vehicle BEV is also used as a low-speed high-power unit to utilize the primary reserve in this preferred exemplary embodiment. The solid line of the grid frequency falls below 50.0 Hz with a latency of, for example, less than 2 seconds, and the building battery B generates a positive primary reserve P FCR However, the grouping and activation of building battery B may occur in advance. Only after grouping and activation, or even during grouping and activation, determination of the grid frequency deviation and provision of reserve in response thereto occurs. In Figure 3, the primary reserve P provided only by building battery B FCR is not sufficient to raise the grid frequency again towards the desired 50 Hz. G will further decrease below 49.9 Hz, whereby further clustered and operated building batteries (shown as dotted lines) and, in parallel therewith, clustered and operated low-speed high-power units BEVs (shown as diagonal lines) will also be used to provide positive reserve. However, this is not done by the EV batteries of the battery electric vehicles BEVs supplying power to the grid N, but by the fact that in this exemplary embodiment, for example, about 50 low-speed high-power units BEVs are coordinated with respect to power consumption from the grid N. This is because the grid frequency f GThe number of building batteries B put into operation can initially be reduced by the increased use of EV batteries BEV. However, the grid frequency f G is then reduced again to the extent that 50 EV-batteries BEVs are used plus a large number of fast building batteries B. In parallel, a further 50 activated EV-batteries BEVs are used, bringing the total to 100 EV-batteries BEVs. The number of installed building batteries B can be significantly reduced while maintaining the use of 100 EV-batteries BEVs. The number of EV-batteries BEVs used is also reduced from 100 to 50, and the grid frequency f G If the rate continues to rise, the 50 operational EV battery BEVs still in use will also be shut down.

[0069] With the corresponding latency offset, the use of slower high-power units in the form of EV batteries BEV occurs in defined circumstances, if they provide the required positive or negative reserve, which allows a corresponding reduction in the number of faster clustered active building batteries B that were previously used. [Explanation of symbols]

[0070] 1. Internet 2 Process Network P Network Connection Point N Power grid PV power plant EFS Energy Flow Control Device SMGW Smart Meter Gateway SM Smart Meter f G Power grid frequency P FCR Reserves, especially primary reserves to stabilize the power grid G. Building wiring network B. Building storage battery TE Power Unit, Technology Unit BEV low speed power unit, especially battery electric vehicle RE spare unit RG spare unit CPE Customer Premises Equipment VPP Virtual Power Plant S Control System M1 Identifying grid frequency deviation M2 Building battery clustering M3 Building storage battery operation M4 Reserve Force Provision M5 Low-speed power units, especially for battery electric vehicles

Claims

1. 1. A method for providing reserve power for stabilizing a power grid (N) and / or providing energy market products using a plurality of building batteries (B), comprising: Each of the building storage batteries is connected to the power grid (N) via a grid connection point (P); each of the building batteries is grouped with other power units (TE1...TEm) in a building distribution network (G1...Gn) defined by the network connection points (P); at least one low-speed power unit (BEV) is present in a plurality of said building networks (G1...Gn), said low-speed power unit requiring a latency of more than 2 seconds for a significant change in power throughput; The method comprises: Identifying (M1) a grid frequency deviation in said grid (N) and / or a demand signal for an energy market product; A step (M2) of clustering a first group of building batteries (B) corresponding to a first group of building wiring networks; A step (M3) of activating a second group of building batteries (B) corresponding to a second group of building wiring networks from the first group of building batteries; (M4) providing by said group of building batteries (B) the reserve power required to offset the determined grid frequency deviation and / or to provide the requested energy market product; Equipped with The method comprises: a step (M5) of using a plurality of low-speed power units (BEVs) in the second group of building distribution networks to take over at least a portion of the building batteries from the second group of building batteries (B) when providing the required power due to the change in power throughput; It is characterized by The method wherein the grouping and operation of the building storage batteries (B) to provide the required power occurs constantly or periodically, and in the process, when providing the required power, the newly operated building storage batteries also take over from the operating building storage batteries already being used to provide power.

2. 2. The method according to claim 1, wherein the insertion of a low-speed power unit (BEV) during the provision of the required power and the disconnection of a building battery (B) during the provision of the required power by the inserted low-speed power unit (BEV) occur constantly or periodically.

3. 3. The method according to claim 1 or 2, characterized in that a plurality of low speed power units (BEV) in the form of battery electric vehicles with EV batteries are used.

4. 4. The method of claim 3, wherein in the case of the battery electric vehicle (BEV), the charging current is monitored for a drop in charging current in a particular manner that characterizes the achievement of full charge of an associated EV battery as an event, and in response to determining such an event, the associated battery electric vehicle (BEV), if it contributed to the achievement of the required power until the determined event, is replaced by another power unit or the associated battery electric vehicle (BEV) is characterized as not currently available for absorption of power.

5. 5. The method according to claim 3 or 4, characterized in that the battery electric vehicle (BEV) contributes to the production of the required power not by power output from the EV battery to the power grid (N) but only by consuming power for charging the EV battery and / or by not consuming power for charging the EV battery.

6. 6. The method according to claim 3, wherein a certain number of operational battery electric vehicles (BEVs) to be charged from the power grid (N) is determined and formed, a maximum possible power consumption from the power grid (N) is defined by this operational number, and an average power consumption of the operational number of battery electric vehicles (BEVs) is set as an operating point by the operational number of battery electric vehicles (BEVs), the average power consumption being in the range of 40% to 60% of the maximum possible power consumption in the absence of significant power grid frequency fluctuations and / or unmet demand for energy market products.

7. Each EV battery belonging to the number of operating battery electric vehicles (BEVs) to be charged from the power grid (U) is There is no power consumption from the power grid (N), the maximum possible power consumption from said power grid (N), and A power consumption between 0% and 100% of the maximum possible power consumption from the power grid (N) 7. The method of claim 6, wherein the control is controlled to a state selected from the group consisting of:

8. 8. The method according to claim 6 or 7, characterized in that the predicted maximum possible power consumption of the number of EV batteries in operation is guaranteed for at least 90 seconds into the future.

9. For a certified Battery Electric Vehicle (BEV), the current state of charge of each said EV battery, whose total charge capacity is known in advance, is analyzed by the following upstream analysis steps of the preceding charging process, namely: storing a charging start date and time of the EV battery; determining and storing the amount of energy absorbed and the charging time required therefor; and determining the state of charge of the EV battery at the start of charging by subtracting the determined amount of absorbed energy from the a priori known total charge capacity, provided that the charging process is terminated without external intervention, thus presuming full charge of the EV battery.

9. The method according to claim 3, wherein the temperature is determined using:

10. 10. The method of claim 9, wherein a statistical analysis of user behavior of the certified battery electric vehicle (BEV) depending on the day of the week and time of day is performed from a plurality of charging processes analyzed in this way to determine the state of charge of the EV battery including an error value and an estimated charging time length that depends only on the charging start date and time.

11. 11. The method according to claim 9 or 10, characterized in that the analysis step of the charging process and / or the statistical analysis of the charging process is performed locally in an energy flow control device of the building wiring network (G) and the results determined therefrom are stored locally.

12. 12. The method of claim 11 when dependent on claim 9, wherein the state of charge of the EV battery and the estimated charging time length are used as a result of the statistical analysis of user behavior depending on day of week and time of day to determine an operating point for providing required power by a certain number of operational battery electric vehicles (BEVs).

13. 13. The method of claim 12, wherein the statistically determined parameters including the EV battery's state of charge and estimated charging time length are replaced in whole or in part by specific queries of these parameters from a certified Battery Electric Vehicle (BEV) user.

14. 14. The method according to any one of claims 1 to 13, characterized in that the low-speed technological units (BEVs) are used only above a defined grid frequency deviation threshold.

15. A system for providing reserve power for stabilizing an electricity grid (N) and / or for providing energy market products, comprising: the system comprises a plurality of building distribution networks (G1...Gn), each defined by a respective network connection point (P) and each having a building battery (B) with a latency time of not more than 2 seconds, the building batteries being connected to the power grid (N) via the network connection points (P) of the respective building distribution networks and grouped together with further power units (TE...TEm) in the respective building distribution networks (G1...Gn); at least one low-speed power unit (BEV) is present in each of the plurality of building distribution networks (G1...Gn), and the at least one low-speed power unit requires a latency time of more than 2 seconds for a significant change in power throughput; the system is configured to determine (M1) a grid frequency deviation in the grid (N) and / or a demand signal for an energy market product; 15. The system, comprising a controller further configured to cause the system to perform the method of any one of claims 1 to 14.

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