Method for adapting an electrical power supply to an electrical power demand in an electrical network, control device and computer program

Abstract

A method is specified for adapting an electrical power supply to an electrical power demand in an electrical network. An electrical charging station for coupling to an electrically powered motor vehicle, comprising an electrical energy storage device, is operated in the electrical network. In the method, a vehicle-specific charging plan is determined by a control device of the electrical network depending on a first capacity range and a second capacity range of the electrical energy storage device. The first capacity range is representative of a capacity available to the electrically powered motor vehicle and the second capacity range is representative of a capacity not freely available to the vehicle. Furthermore, an electrical power demand present in the electrical network is determined depending on the vehicle-specific charging plan.In addition, an electrical power supply in the electrical network that is independent of the electrically powered vehicle is determined, whereupon a compensating measure is determined depending on the vehicle-specific charging plan, the electrical power supply and the electrical power demand, whereby the compensating measure adjusts the electrical power supply to the electrical power demand in the electrical network.

Description

The invention relates to a method for adapting an electrical power supply to an electrical power demand in an electrical network, to a corresponding control device and to a computer program.With increasing electrification, there is a challenge in space to cope with increasing energy demand in electric networks. A promising solution for this is the increased use of renewable energy sources which feed additional electrical power into the network. However, power supply from renewable sources is subject to short-term power fluctuations, which must be compensated for. This is done, for example, by the trade of electricity in the electricity market, wherein the prices vary greatly over the course of the day, depending on the supply and demand.In order to conform the electric power supply or the power generation and the electric power demand or the energy consumption in an electric network, flexibility is required on the supply and demand side. Electrical energy stores, in particular electrical energy stores in electrically driven motor vehicles, play a decisive role in this case. In modern electrically driven motor vehicles, uniform electrical energy stores are often installed despite different equipment variants, as a result of which a customer does not have the entire capacity of the electrical energy store freely available, which creates an unused energy store reserve. This unused capacity provides additional flexibility that can be used to effectively balance out variations in the electrical network.The object on which the invention is based is to specify a method for adapting an electrical power supply to an electrical power demand in an electrical network, a corresponding control device and computer program.The object is achieved by the subject matter of the independent claims. Advantageous embodiments are characterized in the dependent claims.According to a first aspect, the invention relates to a method for adapting an electrical power supply to an electrical power demand in an electrical network. An electrical charging station for coupling an electrically driven motor vehicle, comprising an electrical energy store, is operated on the electrical network. In the method, a vehicle-specific charging plan is determined by a control device of the electrical network as a function of a first capacity range and a second capacity range of the electrical energy store. The first capacity range is representative of a capacity available to the electrically driven motor vehicle and the second capacity range is representative of a capacity not freely available to the vehicle. Furthermore, an electrical power requirement present in the electrical network is determined as a function of the vehicle-specific charging plan. In addition, an electrical power supply in the electrical network that is independent of the electrically driven motor vehicle is determined. Furthermore, a compensation measure is determined as a function of the vehicle-specific charging plan, the electrical power supply and the electrical power demand, wherein the electrical power supply is matched to the electrical power demand by the compensation measure.The total capacitance of the electrical energy store is divided into the first capacitance range and the second capacitance range, for example, as a function of a booked version of equipment with respect to the range of the electrically driven motor vehicle. The first capacity range is available to a user of the electric vehicle, wherein the first capacity range is representative of a range that can be covered by the electric vehicle, for example. For example, equipment variants can be added to expand and / or improve the existing equipment. If, for example, the battery capacity is increased by adding an expanding equipment variant in order to be able to cover a longer range with the electrically driven vehicle, the total capacity of the electrical energy store is re-divided into a first and a second capacity range.The vehicle-specific charging plan can be determined, for example, in such a way that both the first and the second capacity range are charged during a charging process, it being possible to define a prioritization between the first and the second capacity range. For example, the first capacity range is prioritized during a charging process. Furthermore, the vehicle-specific charging plan can also be determined in such a way that only the first or the second capacity range is charged. For example, the vehicle-specific charging plan is ascertained as a function of the electrical power supply and the electrical power demand of the electrical network. The vehicle-specific charging plan can additionally comprise discharging processes of the energy store or of the first and / or second capacity range. For example, the vehicle-specific charging plan can be determined in such a way that both the first and the second capacity range are discharged within a discharging process. Furthermore, the vehicle-specific charging plan can also be determined in such a way that only the first or the second capacity range is discharged. For example, a prioritization can likewise be established for corresponding discharging processes. For example, the first capacity range is likewise prioritized during a discharging process.The electrical power requirement of the electrical network is determined taking into account a requested electrical power of the electrical charging station. The electrical power requirement is in particular the sum of the electrical power required by all consumers operated in the electrical network for their intended, unrestricted operation.The electrical power supply is determined as a sum of an electrical power output of at least one power plant of the electrical network and / or purchased electrical power. The electrical power supply is the electrical power available in the electrical network. The electrical power within an electrical network is composed, for example, of a supply power by at least one power plant in the electrical network and of a power. The power is purchased, for example, at an energy market in order to ensure the equilibrium between the generated electric power supply from the at least one power station of the electric network and the electric power requirement in the electric network and in order to ensure a stable supply. The energy market is, for example, an energy market for power trading and system services for network stabilization.In the context of the invention, a "power plant" is to be understood as an electric power source. A coal power plant and / or a nuclear power plant and / or a combined heat plant can be provided as a power plant, for example. At least one hydroelectric power plant and / or at least one photovoltaic plant and / or at least one wind power plant can also be provided as the power plant. In this context, a "power plant" is also to be understood as an energy store, i.e. an electrical energy store or a pumped storage power plant can be provided. A possible power plant in the sense of a power source can also be a motor vehicle which does not draw charging power at an electrical charging station, but rather feeds electrical power into the electrical network. Purchased electric power is power purchased from an electric network of another electric supplier via an energy market.If a motor vehicle is coupled to an electrical charging station and the charging process for the electrical energy store of the motor vehicle is started, the electrical power requirement is thereby increased by the charging power of the electrically driven motor vehicle. If the electrical power demand thereby exceeds the electrical power supply in the electrical network, this can lead to the requirement in an electrical network, for example a public power grid, of a relatively expensive power, for example control power, which compensates or increases the lack of electrical power supply in order to prevent a drop in a supply voltage and / or restrictions on the operation of another load.After a compensation measure has been determined as a function of the vehicle-specific charging plan, the electrical power supply and the electrical power demand, the compensation measure is carried out. For example, the balancing action may be performed by an energy market provider. The compensation measure can be used to adapt the electrical power supply to the electrical power demand accordingly. Furthermore, the compensation measure name advantageously allows the otherwise unused capacity of the second capacity range to be used in order to adapt the electrical power supply to the electrical power demand in the electrical network and thereby efficiently use the available capacity resources of the electrical energy store.For example, in the case of an electrical power demand greater than the electrical power supply in the electrical network, electrical power can be increased or, in the case of an electrical power supply greater than an electrical power demand, electrical energy can be output. For example, a missing electrical power or excess electrical power of the electrical network can be purchased or sold via the energy market, wherein the second capacity region can function as a buffer. Furthermore, the method indicated advantageously makes it possible to reduce energy costs, since it is possible to avoid costly power, for example control power, being purchased at the energy market if electrical power corresponding to the second capacitance range is available or can be fed into the electrical grid by the compensation measure name. Furthermore, the balancing measure enables the electrical power temporarily stored in the energy store corresponding to the second capacity range to be offered in the energy market as power for another electrical network and, if appropriate, a gain in trading to be achieved.According to at least one embodiment of the method, the vehicle-specific charging plan is determined as a function of a current charge level of the electrically driven motor vehicle and a third capacity range, wherein the third capacity range is representative of a capacity reserve of the energy store of the electrically driven motor vehicle.By determining the vehicle-specific charging plan as a function of a third capacity range which is representative of a capacity reserve, a total capacity which can be used for the compensation measure is increased. In an advantageous manner, it is thus possible to react even more effectively to fluctuations in the electrical network and, by means of the compensation measure, to adapt the electrical power supply more effectively to the electrical power demand in the electrical network.By ascertaining the vehicle-specific charging plan as a function of a current charge level, it can be ensured that sufficient electric charge is available within the electrically driven motor vehicle at any point in time in order to avoid aging effects of the electric energy store on account of a deep discharge. The battery life can thus be extended in an advantageous manner.According to at least one embodiment of the method, the compensating measure comprises the second capacitance region of the electrically driven motor vehicle being charged or discharged.The compensation measure allows the electrical power supply to be matched to the electrical power demand. If the electrical energy store of the electrically driven motor vehicle is charged by the compensating measure, for example, electrical charge corresponding to the second capacitance range is removed from the electrical network, as a result of which the electrical power supply within the electrical network is reduced by the sum of electrical power corresponding to the second capacitance range. The second capacity range of the electrical energy store thus serves as an intermediate store for electrical power within the electrically driven motor vehicle.If the electrical energy store of the electrically driven motor vehicle is discharged by the compensating measure, the temporarily stored electrical power corresponding to the second capacity range is fed into the electrical network, for example, as a result of which the electrical power supply within the electrical network is increased by the sum of electrical power corresponding to the second capacity range.According to at least one embodiment of the method, the compensation measure comprises the second capacitance range and / or the third capacitance range being released to the electrically driven motor vehicle for use.By enabling the second and / or third capacitance range, the capacitance available to the user of the electrically driven motor vehicle can be increased, as a result of which, for example, a longer range of the electrically driven motor vehicle can be achieved. For example, the second and / or third capacity range can be enabled by the compensation measure if the user of the electrically driven motor vehicle is in an emergency situation and the capacity freely available to the user corresponding to the first capacity range is not sufficient to be able to react to the emergency situation. For example, this may be a scenario in which the vehicle user has to drive to a hospital, which, however, would not be sufficient to reach the hospital to capacity corresponding to the current charge level of the electrically powered motor vehicle.Furthermore, by enabling the second and / or third capacitance range, it is possible to react to an aging-related reduction in the first capacitance range by additionally providing the vehicle user with capacitance at the level of the aging-related loss of capacitance from the second and / or third capacitance range. For example, this enabled capacitance can be made permanently available to the user of the electrically driven motor vehicle. Advantageously, the user of the electrically driven motor vehicle accordingly does not experience an aging-induced reduction in the available capacity or the range of the electrically driven motor vehicle that can be covered.According to at least one embodiment of the method, the compensating measure comprises offering an electrical power corresponding to the first capacitance range and / or third capacitance range on an energy market.By offering the electrical power corresponding to the first and / or third capacity range on an energy market, the temporarily stored electrical power can be taken from the electrical energy store of the electrically driven motor vehicle. Furthermore, the temporarily stored electrical power corresponding to the first and / or third capacity range can be removed from the electrical network by offering on the energy market and fed into another electrical network. For example, a trade gain can be achieved by selling the electrical power offered depending on the current market price.According to at least one embodiment of the method, the compensation measure is determined and carried out as a function of a charging and / or discharging intention of a user of the electrically driven motor vehicle.The fact that the compensation measure is ascertained and carried out as a function of a charging and / or discharging intention of the user ensures that the user is not restricted in the use of the electrically driven motor vehicle by the compensation measure. For example, charging and / or discharging operations of the first capacity range by the user of the electrically driven motor vehicle have a priority over the compensation measure. For example, the charging and / or discharging intention of the user can be determined by a predicted or predefined departure time. Furthermore, charging and / or discharging intention of the user can be predicted, for example, by using applied user profiles.According to a second aspect, the invention relates to a control device for adapting an electrical power supply to an electrical power demand in an electrical network. The control device has a computing device which is designed to carry out the method described here. All features of the embodiment disclosed in connection with the method are therefore also disclosed in connection with the control device and vice versa.According to a third aspect, the invention relates to a computer program for adapting an electrical power supply to an electrical power demand in an electrical network, comprising instructions which, when the computer program is executed by a computer, cause the computer program to execute the method for adapting an electrical power supply to an electrical power demand in an electrical network.Exemplary embodiments of the invention are explained in more detail below with reference to the schematic drawings.The following are shown: FIG. 1 shows a flow diagram of a program for adapting an electrical power supply to an electrical power demand in an electrical network; FIG. 2 shows an exemplary charging or discharging profile of an electrically driven motor vehicle as a function of time; FIG. 3 shows an exemplary charging or discharging profile of an electrically driven motor vehicle as a function of time.Elements of the same construction or function are provided with the same reference numerals across the figures.FIG. 1 shows a flow diagram of a program for adapting an electrical power supply to an electrical power demand in an electrical network.A control device 50 is designed to process the program. For this purpose, the control device 50 has, in particular, a computing unit, a program and data memory, and, for example, one or more communication interfaces. The program and data memory and / or the computing unit and / or the communication interfaces can be formed in one structural unit and / or distributed over a plurality of structural units.The control device 50 may also be referred to as a device for adapting an electrical power supply to an electrical power demand in an electrical network.For this purpose, the program is stored in particular on the program and data memory of the control device 50.The program is started in a step S 1, in which variables can be initialized if necessary.An electrically driven motor vehicle, comprising an electrical energy store, is located, for example, in a state coupled to an electrical charging station. The electrical charging station is operated, for example, within the electrical network. The electrical charging station is, for example, a wallbox.In a step S 3, a vehicle-specific charging plan is determined as a function of a first capacity range B 1 and a second capacity range B 2 of the electrical energy store. The first capacity range B 1 is representative of a capacity of the electrical energy store available to the electrically driven motor vehicle. The second capacity range B 2 is representative of a capacity of the electrical energy store that is not freely available to the electrically driven motor vehicle. The classification of the total capacity of the electrical energy store takes place, for example, when the electrically driven motor vehicle is bought and is, for example, dependent on a booked kit of equipment. For example, corresponding equipment packs, for example for increasing the range, can also be subsequently added by a user of the electrically driven motor vehicle, as a result of which the division of the capacity ranges is adapted.In a step S 5, an electrical power requirement present in the electrical network is determined as a function of the vehicle-specific charging plan. The electrical power requirement is determined, for example, taking into account a requested electrical power of the electrical charging station. The electrical power requirement of the electrical network is determined, for example, as a sum of requested electrical power of the electrical charging station and all further electrical consumers of the electrical network.In a step S 7, an electrical power supply in the electrical network that is independent of the electrically driven motor vehicle is determined. The electrical power supply of the electrical network is determined, for example, as a sum of an electrical power output of at least one power plant of the electrical network.In a step S 9, a compensation measure is determined and carried out as a function of the vehicle-specific charging plan, the electrical power supply and the electrical power demand of the electrical network, wherein the electrical power supply is matched to the electrical power demand in the electrical network by the compensation measure. The balancing action is performed, for example, by an energy market provider. The compensation measure determined is transmitted to the energy market provider, for example, via a cloud solution.The compensation measure comprises, for example, the fact that the second capacitance region B 2 of the electrically driven motor vehicle or of the electrical energy store is charged or discharged. Alternatively or additionally, the compensation measure comprises, for example, the fact that the second capacitance range B 2 and / or the third capacitance range B 3 is enabled for use by the electrically driven motor vehicle. Alternatively or additionally, the compensation measure comprises, for example, that an electrical power corresponding to the first capacitance range B 1 and / or third capacitance range B 3 is offered on an energy market.If the electrical power supply in the electrical network is greater than the electrical power demand, for example, the second capacity range B 2 of the electrical energy store of the electrically driven motor vehicle is charged in order to draw electrical power from the electrical network and temporarily store it in the electrical energy store. If the electrical power supply in the electrical network is less than the electrical power demand, the temporarily stored electrical power from the second capacitance range B 2 is fed back into the electrical network, for example. For example, the electrical power is fed in via an energy market, to which the electrical power can be offered for sale. Depending on the current market price, a trade gain in the energy market can be achieved, for example, by selling.As soon as the compensation measure has been carried out, the adaptation is ended in a step S 11 and can optionally be restarted again.FIG. 2 shows an exemplary charging or discharging profile of an electrically driven motor vehicle as a function of time.The total capacity of an energy store of the electrically driven motor vehicle is divided into three capacity ranges. The first capacity range B 1 represents a capacity available to the electrically driven motor vehicle, the second capacity range B 2 represents a capacity not freely available to the electrically driven motor vehicle, and the third capacity range B 3 represents a capacity reserve of the electrical energy store of the electrically driven motor vehicle, which is also not freely available to the motor vehicle.The state of charge of the motor vehicle relates to the actual capacity of the electrical energy store. The charge levels SOC 1, SOC 3 and SOC 4 correspond here, for example, to 5%, 80% and 100% of the actually present capacity of the electrical energy store. For example, only charging stations corresponding to the first capacitance range B 1 are displayed to the user of the electrically driven motor vehicle. In the scenario from FIG. 2, the user of the electric motor vehicle is displayed accordingly at the actual charge levels SOC 1 and SOC 3 corresponding to 0% and 100%. In the following, charging stations are always related to the actual capacity in the electrical energy store, unless expressly reference is made to the "charging stations indicated to the customer".In the example scenario, the electric powered motor vehicle is charged between times t 0 and t 1. Between the times t 1 and t 2 the user of the electrically driven vehicle uses, for example, the bidirectional charging function in order to feed electrical power from the energy store into his home network. For example, the vehicle-specific charging plan additionally comprises power transmissions between the electrically powered motor vehicle and the home network, or other electrical networks. For example, such power transfer operations have a priority over the balancing action.Between the times t 2 and t 3 the electrical energy store is charged again up to the charge level SOC 3.For example, it is determined that at time t 3 the electric power supply in the electric network is greater than the electric power demand. Furthermore, it is determined, for example, that the user of the electrically driven motor vehicle wishes to use the motor vehicle again only at the time t 6 again. Thus, for example, at time t 3 the second capacity range B 2 of the electrical energy store is charged by the compensation measure as a function of the vehicle-specific charging plan, the electrical power supply and the electrical power demand. By charging the second capacitance range B 2, electrical power is taken from the electrical network, as a result of which the electrical power supply is matched to the electrical power demand in the electrical network.For example, at time t 4 it is determined that the electrical power supply in the electrical network is less than the electrical power demand, whereby the electrical power of the second capacitance range B 2 of the electrical energy store is supplied and sold on an energy market, for example, by the compensation measure. For example, a commercial gain is achieved by selling the electric power in the energy market.For example, at time t 5 it is determined that the electric power supply is not greater than the electric power demand, whereby recharging of the capacity range B2 does not reduce a difference between the electric power supply and the electric power demand and thus no compensation measure is performed. For example, at time t 6 the user starts a trip with the electrically driven motor vehicle, whereby the charge level is reduced again.FIG. 3 shows a further exemplary charging and discharging profile of an electrically driven motor vehicle as a function of time.In the exemplary scenario, the electrically driven motor vehicle is driven 1 until the time t and connected in 1 at an electrical charging station at the time t, wherein no charging process is started in this exemplary scenario. The time period between t 1 and t 2 represents, for example, a longer service life in which the charge level is reduced to SOC 1 by self-discharge of the electrical energy store. The third capacity range B 3, representative of the range from a fully discharged electrical energy store to a charge level of SOC 1, serves here merely as a reserve range of the electrical energy store and to avoid aging effects due to deep discharge.For example, at time t 2 it is determined that the electrical power supply is greater than the electrical power demand in the electrical network. Furthermore, the user of the electrically driven motor vehicle does not recognize, for example, an intention to start a charging process. Thus, by the balancing measure, the electric energy storage is charged according to the capacitance of the second capacitance region B 2. For example, at the time t 3 the charging process is ended again after exactly that electric power which corresponds to the capacitance of the second capacitance range B 2 has been fed into the electric energy store.Furthermore, at the time t 3 the electrical power supply is still greater than the electrical power demand in the electrical network. A balancing measure for discharging the buffered electrical power would therefore not reduce the difference between the electrical power supply and the electrical power demand and is therefore not carried out. The electrical power corresponding to the second capacitance range B 2 accordingly remains temporarily stored in the electrical energy store. A self-discharge of the electrical energy store is not taken into account at this point between the points in time t 3 and t 4. For example, the user of the electrically driven motor vehicle starts a charging process at the time t 4. During the charging process indicated by the user, electrical power corresponding to the first capacity range B 1 is fed into the electrical energy store between the points in time t 4 and t 5.At the start of the charging process, the user of the electrically driven motor vehicle is indicated to a fully discharged charge level of the electrical energy store at time t 4 and a fully charged charge level of the electrical energy store at time t 5.For example, after the end of the charging process at the time t 5 it is determined that the electrical power supply is smaller than the electrical power demand in the electrical network, as a result of which, for example, the temporarily stored electrical power corresponding to the second capacity range B 2 is offered for sale on an energy market by the compensating measure.If the charge level falls below the charge level SOC 1 for example, the compensation measure can also use electrical power corresponding to the third capacitance range B 3 in addition to the second capacitance range B 2 in order to match the electrical power supply to the electrical power demand in the electrical network. Furthermore, the compensation measure for charging the electrical energy store can also be started when the current charge level in the third capacity range B 3 reaches a critical state which can impair the service life of the electrical energy store.For example, the user can book portions of the second capacitance region B 2 as equipment variants to the electrically driven motor vehicle in a cost-dependent manner.For example, the user of the electrically driven motor vehicle is not actively informed about the execution of the compensation measure. For example, the compensation measure is carried out via the electrical charging station of the user, wherein the costs for the charging processes carried out for the compensation measure are handled separately by the user.

Claims

Method for adapting an electrical power supply to an electrical power demand in an electrical network, at which an electrical charging station for coupling an electrically driven motor vehicle, comprising an electrical energy store, is operated, wherein in the method - a vehicle-specific charging plan is determined by a control device of the electrical network as a function of a first capacity range (B1) and a second capacity range (B2) of the electrical energy store, wherein the first capacity range (B1) is representative of a capacity available to the electrically driven motor vehicle and the second capacity range (B2) is representative of a capacity not freely available to the vehicle, - an electrical power demand present in the electrical network is determined as a function of the vehicle-specific charging plan, - an electrical power supply independent of the electrically driven motor vehicle is determined in the electrical network, and - depending on the vehicle-specific charging plan, the electric power supply and the electric power demand, a compensation measure is determined and carried out, wherein the electric power supply is matched to the electric power demand in the electric network by the compensation measure.Method according to Claim 1, wherein the vehicle-specific charging plan is determined as a function of a current charge level of the electrically driven motor vehicle and a third capacity range (B3), wherein the third capacity range (B3) is representative of a capacity reserve of the energy store of the electrically driven motor vehicle.Method according to Claims 1 and 2, wherein the electrical power requirement of the electrical network is determined taking into account a requested electrical power of the electrical charging station.Method according to one of the preceding claims, wherein the electrical power supply is determined as a sum of an electrical power output of at least one power plant of the electrical network and / or purchased electrical power.Method according to one of the preceding claims, wherein the compensation measure comprises the second capacitance region (B2) of the electrically driven motor vehicle being charged or discharged.Method according to one of the preceding claims, wherein the compensation measure comprises the second capacity range (B2) and / or the third capacity range (B3) being enabled for use by the electrically driven motor vehicle.Method according to any of the preceding claims, wherein the balancing measure comprises offering an electric power corresponding to the second capacitance range (B2) and / or third capacitance range (B3) to an energy market.Method according to one of the preceding claims, wherein the compensation measure is determined and carried out as a function of a charging and / or discharging intention of a user of the electrically driven motor vehicle.Control device for an electrical network, wherein the control device comprises a computing device which is configured to carry out a method according to one of the preceding claims.A computer program comprising instructions which, when the computer program is executed by a computer, cause the computer program to carry out the method of any one of claims 1 to 8.

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