Method for charging an electric vehicle, electric vehicle and system

Abstract

The invention relates to a method for charging an electric vehicle (2) at a charging point (3), in which a time-window- and power-level-dependent cost table and a time-window-dependent maximum power table are provided, a consolidated cost table is created from these tables in which the transferred cost table has been merged with the maximum power table, costs of charging services for the power levels available per time window are determined from the consolidated cost table for a specified coupling period, power-level-dependent maximum available energy quantities per time window are calculated from the available power levels and the respective length of the time window, and a charging plan for charging the electric vehicle (2) at the charging point (3) is created.in which the charging needs of the electric vehicle are met by replenishing it with the energy quantities available during the coupling period at the lowest cost of the associated charging capacities, and the electric vehicle (2) is charged based on this charging plan. The invention also relates to a correspondingly equipped electric vehicle (2) and a system.

Description

[0001] The invention relates to a method for charging an electric vehicle at a charging point, in which a time window- and power level-dependent cost table is provided to the electric vehicle, a charging plan for charging the electric vehicle at the charging point is created based on this table, and the electric vehicle is charged according to this charging plan. The invention also relates to a correspondingly configured electric vehicle and a system comprising an electric vehicle and a charging point configured to implement the method. The invention is particularly advantageously applicable to the charging of fully electrically powered electric vehicles.

[0002] DE 10 2009 036 816 A1 discloses a method and a device for controlling charging stations for electric vehicles. To minimize peak power requirements, at least two charging stations are combined into a group, actual charging parameters are exchanged within the charging stations within the group, a load forecast for the group is created based on at least the actual charging parameters, and target charging parameters for the charging stations in the group are determined based on the load forecast.

[0003] DE 10 2013 010 774 A1 discloses a method for operating a charging station 2 for electric vehicles, in which a maximum rated value for a charging current or a charging power is determined, the determined maximum rated value for the charging current or the charging power is transmitted to an electric vehicle electrically coupled to the charging station, a first time interval is determined depending on at least the maximum rated value and the electric vehicle is charged with the maximum rated value of the charging current during the first time interval.To increase the service life of the charging station, a reduced rated value for the charging current and a second time interval are determined, whereby the second time interval determines a duration during which the charging current or charging power may not exceed the reduced rated value, the reduced rated value is transmitted to the electric vehicle and the electric vehicle is charged with a maximum of the reduced rated value of the charging current or charging power during the second time interval.

[0004] DE 10 2018 202 755 A1 discloses a method for adapting an electrical power supply to an electrical power demand in an electrical network on which at least one electric charging station is operated, wherein in the method, a control device of the network for at least one motor vehicle creates a charging forecast which indicates in which future charging period the motor vehicle is expected to exchange electrical energy with the network, a temporal profile of the power demand present in the network is estimated depending on the respective charging forecast, a temporal profile of the power supply in the network is determined, and at least one predetermined compensating measure is triggered for at least one charging period for which it is recognized that the power supply is less than the estimated power demand,whereby at least one compensatory measure aligns the service supply with the service demand.

[0005] US 2017 / 0136894 A1 discloses methods, devices, and systems for exchanging communications between a vehicle and a charging system. The communications may include charging request messages sent or received by the vehicle that define charging details, such as a charging type, charging locations, charging orientation, and / or other information corresponding to the charging requirements for the requesting vehicle. The charging system may respond to the charging request messages by accepting or rejecting the vehicle charging request. In response to accepting the request message, the charging system provides a charge to the vehicle according to the charging details.

[0006] US 2017 / 0140603 A1 discloses a system for vehicle fleet management, comprising: a base management system configured to enable one or more fleet vehicles to receive a vehicle service, the base management system comprising a database, a communication module, and an analysis module, the communication module communicating with the one or more fleet vehicles, the analysis module, and the database; one or more fleet vehicles, each fleet vehicle comprising a vehicle database and each configured to receive a charging service and communicate a vehicle charge level to the communication module; at least one fleet service location configured to transmit a billing price to the communication module and to provide the billing service at the billing price;wherein the analysis module receives the charging price and determines whether the at least one fleet service location is selected to provide the charging service to at least one fleet vehicle operating in a low-charge state; wherein, if the analysis module selects the at least one fleet service location, a charging service is provided to the at least one fleet vehicle operating in a low-charge state by the at least one fleet service location.

[0007] DE 10 2014 223 284 B4 discloses a computer-implemented method for storing electrical charge in an electric vehicle connected to a charging station, the method comprising: obtaining a minimum state of charge for the electric vehicle; determining a time to charge the electric vehicle to a maximum state of charge; notifying a power grid that the electric vehicle is available to store electrical charge for the power grid until the determined time; maintaining a state of charge of the electric vehicle between the minimum state of charge and a threshold state of charge until the determined time by repeatedly charging the electric vehicle to the threshold state of charge and allowing discharging of the electric vehicle to the minimum state of charge until the determined time;and charging the electric vehicle to the maximum state of charge at the specified time, wherein the threshold state of charge is greater than the minimum state of charge and the maximum state of charge is greater than or equal to the threshold state of charge;

[0008] It is the object of the present invention to at least partially overcome the disadvantages of the prior art and, in particular, to provide a computationally particularly simple way of setting up a cost-optimized charging plan for an electric vehicle.

[0009] This object is achieved according to the features of the independent claims. Preferred embodiments can be found in particular in the dependent claims.

[0010] The problem is solved by a method for charging an electric vehicle at a charging point, in which - a time window and performance level-dependent cost table and a time window-dependent maximum performance table are provided, - a consolidated cost table is created in which the (previously provided) cost table has been combined with the (previously provided) maximum performance table, - for a planned coupling period, the costs of charging services for the power levels available per time slot are determined from the consolidated cost table, - the maximum energy quantities available per time window are calculated based on the available power levels and the respective length of the time window, - a charging plan is created for charging the electric vehicle at the charging point, in which the charging requirement of the electric vehicle is met by filling it with the energy quantities available during the coupling period at the lowest cost of the associated charging services, and - the electric vehicle is charged according to this charging plan.

[0011] This method has the advantage that it provides a computationally particularly simple way to set up a cost-optimized charging plan for the electric vehicle within the framework of modern charging systems that provide communication between the electric vehicle and the charging point.

[0012] The electric vehicle can be connected to the charging point via a charging cable (a so-called plug-in electric vehicle) or can be connected inductively. The electric vehicle can be a hybrid vehicle or a fully electric vehicle. The electric vehicle can be, for example, a passenger car, truck, bus, motorcycle, etc.

[0013] Providing the cost table and the maximum power table includes, in particular, providing them to a data processing device, which then creates the charging plan. The data processing device can be a functional part of, for example, the electric vehicle, the charging point, or an external instance such as a backend, a home energy management system, or a cloud computing device.

[0014] If the cost table and the maximum power table are provided to the electric vehicle, this can also be printed out in such a way that the cost table and the maximum power table are transferred to the electric vehicle. In a further development, the tables are transferred from the charging point to the electric vehicle. This in turn requires that the charging point can communicate with the electric vehicle at least unidirectionally, in particular bidirectionally. The communication can take place, for example, via the charging cable, e.g. via PLC or dedicated data lines, or wirelessly, e.g. via NFC, Bluetooth or WiFi. It is also a further development that the tables are transferred to the electric vehicle from an external instance different from the charging point, e.g. via a network. The external instance can be, for example, a backend, a home energy management system or a cloud computer.

[0015] A time window and power level-dependent cost table can be understood in particular as a list of charging costs C, e.g. in percent or in an absolute cost unit per energy unit, e.g. in cents / kWh, per time window and per power level per time window. The cost table is in particular a future-oriented or forecast table, which is provided in particular by the entity supplying the charging point with electrical energy, e.g. by an energy supplier or the operator of a charging park, property, etc. that includes the charging point. Typical forecast horizons are 24 hours, 72 hours or even longer. The forecast horizon is often divided into time windows, the transitions between which are referred to as "support points". The support points can be equidistantly distributed, but do not have to be.The method can advantageously handle both equidistant and non-equidistant sampling points. Time windows with a width of 15 minutes are often used. This cost table can also be referred to as a "provided cost table," "initial cost table," or "basic cost table."

[0016] It is a further development that charging costs are specified as relative numbers, for example, in a percentage range, e.g., [0%; 100%]. This is implemented, for example, in the ISO-15118-2 standard. The relative charging costs can be converted into absolute costs using a scaling factor. The scaling factor can be provided, for example, by the charging point, by an energy supplier, or by a backend, etc.

[0017] It is a further development that the charging costs are monetary costs, e.g. stated in ct / kWh.

[0018] It is a further development that charging costs are ecological costs. These can be expressed, for example, in g(CO2) / kWh. The aim here is to minimize the amount of CO2 generated during a charging process. Alternatively, the ecological costs can refer to a share of renewable energy (in %) per kWh. Here, the aim is not to minimize the share, but to maximize it. This can be achieved using the method by using the complement C = (100% - C') of non-renewable energy as the cost C, not the share C' of renewable energy.

[0019] Within these time windows, several power levels with corresponding charging costs are typically defined, with the power levels indicating disjoint but consecutive ranges of charging power. Such power levels can also be referred to as "tiered" power levels. In general, the respective charging costs for each power level can be set arbitrarily. For example, they can increase or decrease with increasing power levels.

[0020] For example, in a specific time window, three power levels LS1, LS2, and LS3 can be present or defined with LS1 = [0; P1], LS2 = ]P1; P2], and LS3 > P2. In principle, the threshold values ​​P1 and P2 can be assigned to the respective separating power levels LS1, LS2, and LS3 in any way, e.g., according to LS1 = [0; P1], LS2 = [P1; P2], and LS3 ≥ P2, etc. Each of the power levels LS1, LS2, and LS3 is assigned a corresponding cost value C1 (LS1), C2 (LS2), or C3 (LS3), which is charged when power is partially drawn from this power level. The threshold values ​​and cost values ​​of two different time windows can be at least partially different. Furthermore, there is generally no limit to the number of power levels. In a further development, the cost table can therefore include a list of the time windows within the forecast period and, for each of the time windows, their threshold values ​​and costs or values ​​that can be converted into them.

[0021] The time-window-dependent maximum power table corresponds to a table in which, for a future forecast horizon, the corresponding time windows are assigned a respective value of the maximum electrical power that can be drawn or permitted via this charging point. The maximum power table can be generated, for example, by a charging point operator, such as a charging park operator, who can then adjust the maximum power of each charging point depending on the occupancy of the charging points, the prioritization of certain electric vehicles, etc.

[0022] The merging of the cost table and the maximum power table specifically involves limiting or "capping" the power levels of the cost table by the simultaneous maximum values ​​contained in the maximum power table. This is irrelevant if, for a specific period of time, the permitted maximum electrical power available via the charging point exceeds the value that the electric vehicle can actually charge, but is important, for example, if this permitted maximum power is below a threshold. The combined table is referred to herein as the "consolidated cost table," without loss of generality.

[0023] The coupling period or intended coupling period refers in particular to the period for which the electric vehicle is expected to be coupled or connected to the charging point. For example, an actual or expected arrival time and an expected departure time can be specified. During the coupling period, the electric vehicle can be charged with electrical energy. Determining the costs of charging services "for an intended coupling period" can, in a further development, include determining the costs for a period corresponding to the entire coupling period. It is also a further development that the costs are determined for a period shorter than the coupling period.This can occur, for example, if the coupling period is very long, such as a vacation period of several weeks, but the tables are only available for one or more days in advance. It may also be the case that the (basic) cost table and the maximum performance table have different lengths or time horizons. In this case, the consolidated cost table can only be determined for the shorter length or time horizon, and in a training course, only for a period for which the starting and end points of the basic cost table and the maximum performance table coincide.

[0024] The costs determined from the consolidated cost table may represent costs per performance level or may represent average costs. This is explained in more detail below.

[0025] In general, charging power and energy quantities can be converted into one another within the framework of this method, since the corresponding times or time periods of the time windows are known. Thus, charging power and energy quantities can be used interchangeably, as long as the context does not indicate otherwise.

[0026] The calculation of the power-level-dependent maximum available energy quantities per time window based on the "available" level of the power levels and the respective length of the time window involves, in particular, multiplying the maximum available or available charging power for each power level of a time window still present in the consolidated cost table by the width of the time window to obtain the respective power-level-dependent energy quantity. The "available" level of a power level corresponds to the upper threshold of this power level or the maximum power specified for this time window from the maximum power table, whichever is lower.At the highest power level, which no longer has an upper threshold, the "available" amount corresponds to the maximum power specified in the maximum power table or the maximum charging power specified by the electric vehicle, whichever is lower. The power-level-dependent energy quantities correspond to the maximum energy quantities that can be drawn from the charging point at the cost of this power level. This advantageously simplifies the preparation of the charging plan. The price for charging this amount of energy can be determined, in particular, from the product of the cost value of the charging power for the power level in question and the width or duration of the time window.

[0027] The goal of cost optimization through the charging plan is, in particular, to enable a more cost-effective charging process than, for example, with instant charging at maximum charging power. To achieve this, the most cost-effective charging times and power levels or energy quantities are preferentially used.

[0028] The creation of a charging plan for charging the electric vehicle at the charging point where the charging requirement of the electric vehicle is met by topping up or accumulating the energy quantities available during the coupling period at the lowest cost of the associated charging services includes, in particular, successively accumulating or adding energy quantities associated with the lowest costs until the charging requirement, i.e., the amount of energy to be charged during the coupling period, is met or reached. Since the selected energy quantities are linked to specific time windows, the resulting charging plan represents a temporal progression of the energy quantities to be charged per time window of the consolidated cost table over the coupling period under consideration.

[0029] The amount of energy to be charged can, for example, be determined from the difference between the charge level of the drive battery(ies) desired by the customer at the expected departure time (so-called "destination SoC") and the charge level of the drive battery(ies) at the arrival time (so-called "start SoC"), multiplied by the battery capacity and, if necessary, taking into account charging losses, etc.

[0030] The fact that the electric vehicle is charged on the basis of this charging plan can, in a further development, include the electric vehicle being charged according to exactly this charging plan. The associated charging process can be controlled by the electric vehicle or can be controlled by the charging point or an energy management system that is higher up the charging point. In the first case, the charging plan can be kept in the electric vehicle, in the second case in the charging point. The first case is particularly advantageous if the rectifier is located in the electric vehicle (so-called “AC charging”). The second case is particularly advantageous if the rectifier is located in the charging point (so-called “DC charging”). It is also possible for the charging plan created using the above method to be changed again, e.g. by the charging point or the energy management system.

[0031] It is a further development that the charging plan takes into account further criteria, for example a maximum charging power permitted by the electric vehicle, a maximum permitted number of charging interruptions, etc. For example, the charging power permitted by the electric vehicle can be below, above or at the level of the maximum power of the charging point specified in the maximum power table.

[0032] It is a further development that the charging plan is or can be updated, e.g. because its boundary conditions have changed, such as the costs of the power levels, the permitted maximum power, the power limits, the departure time, etc.

[0033] It is a further development that the costs of charging capacities determined from the consolidated cost table for the power levels available per time slot correspond (directly) to the costs per power level, e.g. C1 (LS1), C2 (LS2) or C3 (LS3). Determining the costs can then correspond to adopting the costs from the (basic) cost table. This further development is particularly easy to implement. It is particularly advantageous in the case of a "progressive" cost structure per time slot, i.e. the costs do not decrease with higher power levels, but in particular increase, e.g. according to C1 (LS1) ≤ C2 (LS2) ≤ C3 (LS3). This can occur, for example, if an energy supplier wants to penalize higher charging capacities, for example if it has to expand the infrastructure for this. These costs per individual charging capacity can also be referred to as "individual costs" or "individual stage costs".

[0034] It is a design that the costs determined from the consolidated cost table are average costs or average costs of charging capacities, which are calculated for the power levels available per time slot. In a further development, this includes calculating the average costs for each of the power levels of a time slot in the consolidated cost table across the charging capacities used in this power level and all lower power levels. This further development is particularly advantageous in the case of a "degressive" cost structure of the power levels per time slot, i.e. the costs become lower with higher power levels, e.g. according to C1 (LS1) > C2 (LS2) > C3 (LS3). This can be the case, for example, if an energy supplier grants a volume discount or if, in the case of a property with an autonomous energy generation facility, e.g.Photovoltaic systems, even older contracts with high feed-in tariffs exist, which generate more revenue than the current electricity price when purchased.

[0035] If, for example, a certain time window in the consolidated cost table has three power levels, the average costs when charging at a power level within the lowest power level can be equated with the individual costs of this power level, since averaging is not necessary when charging from only one power level. The average costs when charging at a power level within the middle power level can, for example, be averaged from the individual costs for charging within the entire lowest power level and the individual costs for charging within the middle power level. The average costs when charging at a power level within the highest power level can, for example, be averaged from the respective individual costs for charging within the entire lowest and middle power levels and the individual costs for charging within the highest power level.For each time window of the consolidated cost table, as many average values ​​can be determined or calculated as there are performance levels available.

[0036] One embodiment is that for the, in particular all, time windows considered (e.g., within the coupling period), the maximum available energy quantities per power level are ranked according to the (individual or average) costs of the associated charging power, and the charging plan is created by filling the charging power and / or associated energy quantities in order from low to high costs. This is advantageously particularly easy to implement. In order from low to high costs, one can successively withdraw the corresponding energy quantities per charging window and per power level, thus creating a charging plan until the desired energy quantity is reached. For example, value pairs (Ci,k¯;Ei,k) with Cι,k¯ the average cost of a k-th power level in an i-th time window and E i,k the corresponding maximum available amount of energy in a sequence {…,(Ci,k¯;Ei,j),…} with sequence from small to larger Cι,k¯ be lined up, analogously for individual costs.

[0037] One embodiment is that the time points of the cost table and the maximum performance table are identical. This advantageously facilitates their merging. The fact that the time points are identical includes, in particular, that the time windows underlying the cost table and the maximum performance table are congruent.

[0038] One embodiment is that at least some temporal support points of the cost table and the maximum performance table differ (i.e., not all time windows coincide, or for at least one support point in the cost table, there is no corresponding support point in the maximum performance table, and / or vice versa), and the consolidated cost table includes all temporal support points of the cost table and the maximum performance table. This advantageously allows a cost-optimized charging plan to be created even if the width and / or position of the time windows of the cost table and the maximum performance table differ.For example, if a reference point in the maximum performance table lies within a time window of the cost table, two time windows can be used in the consolidated cost table instead of the time window of the cost table: a first time window from the beginning of the time window of the cost table to the reference point of the maximum performance table, and a second time window from the beginning of the reference point of the maximum performance table to the end of the time window of the cost table, e.g., with the same performance levels but possibly different maximum performance. In general, if n is the number of reference points in the cost table, m is the number of reference points in the maximum performance table, and p is the number of reference points in the consolidated cost table, then p ≤ n + m. If all reference points are different except for the start and end times, p = n + m - 2.

[0039] It is an advantageous arrangement in the event that the costs correspond to average costs, that for the average costs Cι,k¯ the charging power P L ≤ the maximum power M i for an i-th time window with a maximum of k = 3 performance levels of the consolidated cost table Cι,1¯=Ci,1 for k = 1 or the lowest power level LS1 applies, because no power share is drawn from another power level. In other words, if the electric vehicle uses electrical charging power P in the i-th time window L ≤ P i,1 with P i,1 the first threshold of the charging power, the associated average costs are the (individual) costs C i,1 .

[0040] For a request for a charging power P i,1 < P L ≤ P i,2 corresponding to k = 2 or from the middle performance level LS2 applies to the average costs Cι,2¯ Cι,2¯={(Pi,1⋅Ci,1)+(PL−Pi,1)⋅Ci,2}1PL with C i,2 the (individual) charging costs between P i,2 and P i,1 .

[0041] For a request for a charging power P i,2 > P L corresponding to k = 3 or from the highest performance level LS3 applies to the average costs Cι,3¯ Cι,3¯={(Pi,1⋅Ci,1)+(Pi,2−Pi,1)⋅Ci,2+(PL−Pi,2)⋅Ci,3}1PL there here to P i,1 the individual costs C i,1 accrue, following to P i,2 the individual costs C i,2 and only from P i,2 the individual costs C i,3 for the third performance level.

[0042] This calculation scheme can be extended to more than three power levels, e.g. according to the formula for the highest power level k Cι,k¯={(Pi,1⋅Ci,1)+[∑j=2k−1(Pi,j−Pi,j−1)⋅Ci,j]+(PL−Pi,k−1)⋅Ci,k}

[0043] The for the k-th power level LS kwith the average costs Cιk¯ maximum available amount of energy E i,k corresponds to Ei,k=Pι,k˜⋅(ti−ti−1) with t i-1 the initial time and t i the end time of the i-th time window and Pι,k˜=min (Pi,k;Mi) fu¨rk <kmax sowie Pκ,k˜=Mi fu¨r k=kmax.

[0044] One configuration is that energy quantities for specific time windows and power levels are not considered if their power level-related average costs are higher than the average costs for calling up a charging power with a higher power level. This can advantageously prevent non-cost-optimized charging by charging at higher costs with lower energy quantities within a specific time window. This can also be expressed as value pairs (Cι,p¯;Ei,p) be ignored for an i-th time window if Cι,p¯>Cι,q¯ Cl,q¯ with p < q. For example, pairs of values ​​(Cl,1¯;Ei,1) can be ignored if Cl,1¯>Cl,2¯ or Cl,1¯>Cl,3¯ applies, value pairs (Cl,2¯;Ei,2) be disregarded if Cl,2¯>Cl,3¯ applies, etc.

[0045] It is an advantageous design, for example for reasons of efficiency, that charging powers or the corresponding energy quantities are not taken into account whose charging powers are below a predetermined minimum power threshold P min lay.

[0046] One embodiment is that the replenishment with the energy quantities includes replenishment with the maximum charging power per power level considered. In other words, if charging power is to be taken from a specific power level, the maximum possible charging power for this power level is set or selected. For example, if a charging power P is to be used for a specific i-th time window, L,j are taken from the j-th power level, the charging power is set to P L,j = min {Pi,j; M i} with M i the maximum charging power of the i-th time window, if possible. For the highest power level, P L = M i , if possible.

[0047] The design allows for a maximum of three performance levels to be available or defined per time slot. This creates a favorable balance between a tiered cost structure and low data volumes.

[0048] One embodiment involves transmitting the cost table and maximum power table to the electric vehicle in accordance with ISO standard 15118-2. This is particularly advantageous because this standard can describe the cost table and maximum power table very precisely (namely, with up to 1024 temporal reference points each, and with regard to the cost table, with up to three power levels per temporal reference point). ISO standard 15118-2 describes standardized communication between the charging point and the electric vehicle regarding the charging process. In so-called "scheduled mode," dynamic cost tables and maximum power tables are transmitted from the charging station to the electric vehicle. The electric vehicle can use these tables to calculate the charging plan. The consolidated cost table can therefore contain up to 2048 reference points.

[0049] The task is also solved by an electric vehicle that is designed to - to receive a time slot and power level dependent cost (basic) table and a time slot dependent maximum power table from a charging point, - to create a consolidated time-window and performance-level-dependent cost table from these tables, in which the (basic) cost table has been merged with the maximum performance table, - to calculate the average costs of charging services for the power levels available per time slot from the consolidated cost table, at least for a planned coupling period, - to calculate the maximum energy quantities available per time window, depending on the power level and the respective length of the time window, - to draw up a charging plan for charging the electric vehicle at the charging point where the charging requirement of the electric vehicle is met by replenishing it with the energy quantities available during the coupling period with the lowest average cost of the associated charging services.

[0050] The electric vehicle can be designed analogously to the method, and vice versa, and has the same advantages. In particular, the electric vehicle has a rectifier configured for AC charging.

[0051] One embodiment allows the electric vehicle to be charged according to this charging plan. The electric vehicle, the charging point, or an energy management system encompassing the charging point can control the charging process according to the charging plan.

[0052] However, the calculation of costs, in particular average costs, the calculation of the maximum available energy quantities per time window and / or the creation of the charging plan can be carried out in an external instance such as a backend, a home energy management system or a cloud computer that is in direct or indirect communication with the electric vehicle (e.g. via the charging point).

[0053] The object is further achieved by a system comprising an electric vehicle, in particular as described above, and a charging point that can be coupled thereto for charging the electric vehicle, wherein the system is configured to carry out the method as described above. The system can be designed analogously to the method and / or to the electric vehicle and has the same advantages.

[0054] It is a design that the charging point is a charging point of a public charging station.

[0055] One embodiment is for the charging point to be a wallbox on a property. The property can be, for example, a private property such as a single-family or multi-family home. A further development is for the property to have at least one autonomous energy supply facility, such as a photovoltaic system, a heat pump, and / or a wind turbine, etc.

[0056] It is a further development that the charging point is a charging point, e.g. a wallbox, of a property with at least one autonomous energy supply device and the charging point provides a maximum of three power levels, namely per time slot - where there are three power levels: a first, lowest power level corresponding to a supply from a non-regenerable surplus, a second, medium power level corresponding to a supply from a regenerable surplus and a third, highest power level corresponding to a supply from an energy supply network; - where there are two power levels: a first, lowest power level corresponding to a supply from a regenerative surplus and a second, medium power level corresponding to a supply from the power grid; and - where there is only one power level: a first, lowest power level corresponding to a supply from the energy supply network.

[0057] The above-described properties, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following schematic description of an embodiment, which is explained in more detail in connection with the drawings. Fig. 1 shows a system configured to carry out the method according to the invention; Fig. 2 shows a possible content of a cost table transferred from the charging point to the electric vehicle; Fig. 3 shows a possible content of a maximum power table transmitted from the charging point to the electric vehicle; Fig. 4 shows a possible content of a cost table from the content of Fig. 2 and the contents of the maximum performance table from Fig. 3 consolidated cost table; Fig. 5 shows a consolidated cost table for the Fig. 1 system shown; Fig. 6 shows a consolidated cost table from Fig. 5 charging plan for an initial connection period; and Fig. Figure 7 shows a consolidated cost table from Fig. 5 charging plan for a second connection period.

[0058] Fig. Figure 1 shows system 1, comprising an electric vehicle 2 and a charging point 3 of a property 4 that can be coupled thereto for charging the electric vehicle 2. The electric vehicle 2 is connected to the charging point 3 by means of a charging cable 5 and can exchange data with the charging point 3 in accordance with ISO standard 15118-2. The charging point 3 can be supplied with electrical energy from a public energy supply grid 6 and optionally from an autonomous energy supply device 7 such as a photovoltaic system, etc.

[0059] According to the ISO 15118-2 standard, in “Scheduled Mode” a cost table Tab c (see Fig. 2) and one from the charging point 3 to the electric vehicle 2, each up to 1024 support points and with regard to the cost table Tab c with up to three power levels per time base. Electric vehicle 2 is configured to generate a consolidated cost table (Tab) from these tables. c,kon (see Fig. 4) and from this a cost-optimized charging plan.

[0060] Fig. 2 shows in graphic form as a plot of a charging power P available by the electric vehicle 2 L in kW against time t in e.g. seconds a possible content of a cost (basic) table transferred from the charging point 3 to the electric vehicle 2 Tab c .

[0061] Starting from an initial time t0, the cost table Tab ca time series of i = 1, ..., n time windows Zf i , the width of which can be different. This means that the corresponding support points t0 to t n-1 , which correspond to the starting times of the respective time windows Zf i correspond, do not need to be distributed equidistantly over time t. Each of the time windows Zf i can be staggered up to k = 3 power levels LS i,k , with the first two power levels LS i,1 and LS i,2 by the respective first limit value P i,1 are separated and the power levels LSi,2 and LS i,3 by the respective second limit value P i,2 are separated. Each of the power levels LS i,k is a respective (individual) cost value C i,k assigned to the charging power P L only from this power level LS i,k It should be noted that when a charging power P is requested, Lfrom a higher power level LS i,k with k > 1 the total or average cost per time slot Zf i staggered from the individual costs of each performance level used LS i,k this time window Zf i The limit values ​​P i,k and the costs C i,k may vary from time slot to time slot.

[0062] In this case, the time windows shown comprise, purely by way of example, three power levels each, except for time window Zf2, which only has two power levels LS 2,1 and LS 2,2 It is also generally possible that at least one time slot has only one power level.

[0063] Fig. 3 shows in graphic form a plot of a charging power P available by the electric vehicle 2 L in kW against time t in s a possible content of a maximum power table Tab transmitted from the charging point 3 to the electric vehicle 2M .

[0064] Starting from a starting time T0, the maximum performance table Tab M a time series of j = 1, ..., m time windows Zf' j , the width of which can be different and also differ in width, number and position from the time windows Zf i the cost table tab c This means that the corresponding support points T0 to T m-1 , which correspond to the starting times of the respective time windows Zf' j do not need to be distributed equidistantly over time t. Each of the time windows Zf' j has a maximum power M j which can vary from time slot to time slot. The maximum power M jcan be determined, for example, by the charging point 3 or an energy management system managing the charging point 3. For example, a property such as a single-family house can have a certain maximum power M j This can occur when the available power needs to be distributed across various electrical consumers on the property. These could include, for example, several electric vehicles that need to be charged, but also heat pumps or household appliances such as stoves, washing machines, etc.

[0065] Fig. 4 shows in graphic form as a plot of a charging power P that can be accessed by the electric vehicle 2 L in kW against time t in s a possible content of one of the contents of the cost table Tab c out of Fig. 2 and the contents of the maximum performance table Tab M out of Fig. 3 merged consolidated cost table tab c,kon . The consolidated cost table Tab c,konresults from overlaying the cost table Tab c and the maximum performance table Tab M on the same time axis. It can also be interpreted as the maximum power M j the available charging power P L the corresponding time windows Zf i the cost table tab c This allows for a lower cost compared to the cost table Tab c In the consolidated cost table, performance levels are eliminated or their amount is limited. Are the time windows Zf i and the time windows Zf' j on the common time axis do not coincide, new time windows Zf* can be created in the consolidated cost table Tab c,kon be created.

[0066] In the consolidated cost table tab c,kon It is indicated that the time windows Zf1 and Zf'1 are congruent, where M1 < P 1,2Thus, the first time window Zf*1 of the same width contains only one first power stage LS* 1,1 = LS 1,1 and a second power level LS* 1,2 whose height is less than LS* 1,2 . The third performance level LS 1,3 from the (non-consolidated) cost table Tab c is omitted. The (individual) costs C 1,1 and C 1,2 are taken from the cost table Tab c taken over.

[0067] The second time window Zf*2 is separated from the time window Zf2 by M2 in the second power level LS* 2,2 performance-limited.

[0068] An r-th time window Zf* r results from the time window Zf i and the maximum value M j . Since the support point Tj-1 of the corresponding time window Zf' j , within the time window Zf i , the time window Zf* r only between the times z r-1 = t i-1 = Tj-1 on the one hand and z r = T j on the other hand.

[0069] An (r+1)-th time window Zf* r+1 results from the time window Zf i and the maximum value M j+1 and thus extends between z r = T j on the one hand and z r+1 = t i on the other hand.

[0070] An (r+2)-th time window Zf* r+2 results from the time window Zf i+1 and the maximum value M j+1 and extends between z r+1 = t i on the one hand and z r+2 = T j+2 on the other hand.

[0071] Since the time windows Zf i and Zf' j are not congruent in this example, the consolidated cost table Tab c,kon more time slots Zf* r on as the cost table tab c and the maximum performance table Tab M , which can also be written as N > max (n; m).

[0072] Fig. 5 shows a consolidated cost table for the Fig. System 1 shown in Figure 1 with a plot of an available charging power P L in kW against a time t in the form of a time in hours for a whole day between 0 h and 24 h. The maximum power is limited to M = 20 kW for the whole day, which corresponds to the structurally determined maximum charging power of charging point 3. The different 1-h time windows Zf* i = [i-1; i[h can have a different number and level of performance levels. The unit costs C i,j of the j power levels have for each of the time windows Zf* i , so that a calculation of average costs is not necessary. Thus, the time windows Zf*1 to Zf*6 and Zf* 22 to Zf* 24 a first power level LS* i,1 with (charging) costs C i,1 of 30 cents / kWh, for example. The time windows Zf*7 to Zf* 10and Zf* 18 to Zf* 21 each have two power levels LS* i,l and LS* i,2 with (charging) costs C i,1 = 7 ct / kWh or C i,2 = 30 cents / kWh. The time windows Zf* 11 to Zf* 17 each have three performance levels LS* i,1 , LS* i,2 and LS* i,3 with (charging) costs C i,1 = 0 ct / kWh, C i,2 = 7 ct / kWh or C i,3 = 30 ct / kWh.

[0073] In system 1, this corresponds to the scenario that purchasing electrical energy from the energy supply network 6 costs 30 cents / kWh and between midnight and 6 a.m. and between 9 p.m. and midnight the energy requirement for charging the electric vehicle 2 must be completely covered by the energy supply network 6, since the autonomous energy supply device 7 then does not yet generate or does not generate enough electricity for a surplus from the property 4.

[0074] Between 6 a.m. and 9 p.m., a surplus is generated at property 4 due to the electricity generated by the autonomous energy supply facility 7. This surplus could be fed back into the energy supply grid 6 with a feed-in tariff of 7 cents per kWh. If, instead, electric vehicle 2 is charged from the surplus, the operator of property 4 loses the corresponding feed-in tariff, so the cost of charging electric vehicle 2 from the feed-in surplus is 7 cents per kWh.

[0075] In this case, the boundary condition also applies that property 4 is permitted to feed a maximum of 7 kW into or back into the energy supply grid 6. If the autonomous energy supply facility 7 generates more than 7 kW of excess electrical power, the power generation of the autonomous energy supply facility 7 must be reduced or the non-regenerable surplus portion must be consumed. If the non-regenerable surplus portion is used to charge the electric vehicle, as is possible here between 10 a.m. and 5 p.m., this is free of charge or, taking production costs into account, practically free of charge, so that C i,1 = 0 ct / kWh.

[0076] Overall, in this embodiment, for each time window, lower performance levels have lower costs than higher performance levels.

[0077] Fig. 6 shows a plot of a charging power P Lin kW on the left x-axis and a charged energy quantity E L in kWh against a time t in the form of a time in hours for a part of the day between 4 h and 16 h, a calculation based on the consolidated cost table from Fig. 5 charging power for a first connection period, during which the electric vehicle 2 is connected to the charging point 3 between midnight and 3 p.m. The timing of the charging power P L corresponds to a charging plan that integrates an energy E charged into the drive battery(ies) in a time curve shown LZK1 L can be converted. For example, an amount of energy E L = 40 kWh can be charged into electric vehicle 2.

[0078] To create a charging plan, the cheapest charging services during the connection period, at 0 cents / kWh, are first selected, followed by the slightly more expensive charging services at 7 cents / kWh. This is sufficient to avoid the most expensive charging services at 30 cents / kWh. The total cost of the charging process in this example is (9 kW × 0 + 31 kW × 7) cents / kWh × 1 h = €2.17.

[0079] This corresponds to a calculation based on average costs, whereby the calculation can be simplified in this case, since lower performance levels for all time windows of the connection period result in lower costs (individual) costs C i,k than higher performance levels in this regard. This is because the individual performance levels LS* i,k available energy quantities E (LS* i,k ) generally according to the (individual) costs C allocated to these performance levels i,k be arranged, e.g. in pairs of values ​​{C i,k; E (LS* i,k )}. However, the ranking can also be calculated and established based on the average costs. For example, for the time window Zf* 12 between 11am and 12pm average cost C12.2¯ for the first two performance levels LS* 12,1 and LS* 12,2 of [(6 kW · 7 ct / kWh) + (2 kW · 0 ct / kWh)] / 8 kW = ([42 + 0] / 8) ct / h = 5.25 ct / h.

[0080] The charging plan may, for example, have been created taking into account other boundary conditions, such as the condition of as few interruptions as possible, the lowest possible charging power P L , loading as quickly as possible or later or delayed, etc.

[0081] Fig. 7 shows in a Fig. 6 analogous plot based on the consolidated cost table from Fig.5 established charging plan for a second connection period between 0 o'clock and 9 o'clock together with a time profile LZK2 of an analogue energy E charged into the traction battery(ies) L . Here too, a total amount of energy E L = 40 kWh can be charged into electric vehicle 2.

[0082] To create a charging plan, in this example, the cheapest charging capacities during the connection period are first taken at 7 cents / kWh and then supplemented with the more expensive charging capacities at 30 cents / kWh. Charging capacities with 0 cents / kWh are not available in the second connection period. The total cost of the charging process in this example is (11 kW × 7 cents / kWh + 29 kW × 30 cents / kWh) × 1 h = €9.47. This is still cheaper than immediate charging immediately after connection at midnight with a maximum charging capacity of, for example, 20 kWh, which would incur a charge of 40 kWh × 30 cents / kWh × 1 h = €12.

[0083] Of course, the present invention is not limited to the embodiment shown.

[0084] In general, “a”, “an”, etc. can be understood as a singular or a plural, in particular in the sense of “at least one” or “one or more”, etc., as long as this is not explicitly excluded, e.g. by the expression “exactly one”, etc.

[0085] A numerical value may also include the exact number stated as well as a usual tolerance range, as long as this is not explicitly excluded. List of reference symbols 1 system 2 electric vehicles 3 charging points 4 Property 5 charging cables 6 Energy supply network C i,k Costs of the k-th performance level of the i-th time window of the cost table E L Amount of energy charged LS i,kk-th performance level of the i-th time window of the cost table LS* r,k k-th performance level of the r-th time window of the cost table M j Maximum performance P i,k k-th threshold of the i-th time window P L Charging power t time tab c provided cost table tab M provided maximum power table tab c,kon consolidated cost table t i Dates of the cost table T j Times of the maximum performance table z r Dates of the consolidated cost table Zf i i-th time window of the cost table Zf' i j-th time window of the maximum power table Zf* r r-th time window of the consolidated cost table QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2009 036 816 A1

[0002] DE 10 2013 010 774 A1

[0003] DE 10 2018 202 755 A1

[0004] US 2017 / 0136894 A1

[0005] US 2017 / 0140603 A1

[0006] DE 10 2014 223 284 B4

[0007]

Claims

[1] Method for charging an electric vehicle (2) at a charging point (3), in which - a time window and performance level dependent cost table (Tab c ) and a time-window-dependent maximum performance table (Tab M ) are provided, - from these tables (Tab c , Tab M ) a consolidated cost table (Tab c,kon ) is created, in which the cost table (Tab c ) with the maximum performance table (Tab M ) has been merged, - for a planned coupling period from the consolidated cost table (Tab c,kon ) Costs C i,k of charging power (P L ) for the per time slot (Zf* r ) available power levels LS* r,k be determined, - from the available level of power levels LS* r,k and the respective length of the time window (Zf* r) power level-dependent maximum available energy quantities per time window (Zf* r ) are calculated, - a charging plan for charging the electric vehicle (2) at the charging point (3) is created, in which a charging requirement of the electric vehicle (2) is met by filling with the energy quantities available in the coupling period at the lowest cost C i,k the associated charging power (P L ) is reached, and - the electric vehicle (2) is charged based on this charging plan. [2] Method according to claim 1, in which the consolidated cost table (Tab c,kon ) Average costs of charging services (P L ) for the per time slot (Zf* r ) available power levels LS* r,k (3) is created, in which a charging requirement of the electric vehicle (2) is met by filling it with the energy quantities available in the coupling period with the lowest average costs of the associated charging power (PL ) is reached. [3] Method according to one of the preceding claims, in which for the considered time windows (Zf* r ) the maximum available energy quantities per power level LS* r,k according to costs C i,k the associated charging power (P L ) and the loading plan C i,k by replenishing the energy quantities in order from low to higher costs C i,k is created. [4] Method according to one of the preceding claims, in which at least some temporal support points (t i , T j ) of the cost table (Tab c ) and the maximum performance table (Tab M ) and the consolidated cost table (Tab C,kon ) all temporal support points (e.g. r ) of the cost table (Tab C ) and the maximum performance table (Tab M ) includes. [5] Method according to one of claims 2 to 4, in which the average costs Cl,k¯ the charging power (P L ) for an r-th time window (Zf* r ) with a maximum of k = 3 performance levels of the consolidated cost table (Tab C,kon ) and P L ≤ M i with M i the maximum power for the r-th time window (Zf* r ) - for a request for a charging power P L ≤ P i,1 in the first performance level LS* r,1 with P r,1 the first threshold between the first performance level and the second performance level corresponding to k = 1 for the average costs Cr,1¯ the relationship Cr,1¯=Cr,1 with C r,1 the costs for the first benefit level apply; - for a request for a charging power P r,1 < P L ≤ P r,2 in the second performance level with P r,2the second threshold value of the charging power between the second power level and the third power level corresponding to k = 2 for the average costs Cr,2¯ the relationship Cr,2¯={(Pr,1⋅Cr,1)+(PL−Pr,1)⋅Cr,2}1PL with C r,2 the costs for the second benefit level; and - for a request for a charging power P L > P r,2 in the third performance level corresponding to k = 3 for the average costs Cr,3¯ the relationship Cr,3¯={(Pr,1⋅Cr,1)+(Pr,2−Pr,1)⋅Cr,2+(PL−Pr,2)⋅Cr,3}1PL with C r,3 the (individual) costs for the third service level. [6] Method according to one of claims 2 to 5, in which energy quantities for certain time windows (Zf* r ) and power levels LS* r,kare not taken into account if their power level-related average costs are higher than the average costs for calling up a charging power with a higher power level. [7] Method according to one of the preceding claims, in which charging powers for a specific time window (Zf* r ) are not taken into account if they are below a specified minimum charging power. [8] Method according to one of the preceding claims, in which the filling with the energy quantities is a filling with maximum charging power per considered power level LS* r,k includes. [9] Method according to one of the preceding claims, in which per time window (Zf* r ) maximum three power levels (LS* r,1 , LS* r,2 , LS* r,3 ) are present. [10] Method according to one of the preceding claims, in which the cost table (Tab c ) and the maximum performance table (TabM ) to the electric vehicle (2) in accordance with ISO standard 15118-2. [11] Electric vehicle (2), wherein the electric vehicle (2) is designed to - a time window and performance level dependent cost table (Tab c ) and a time-window-dependent maximum performance table (Tab M ) to receive, - from these tables (Tab c , Tab M ) a consolidated time window and performance level dependent cost table (Tab c,kon ) in which the transferred cost table (Tab c ) with the maximum performance table (Tab M ) has been merged, - for a planned coupling period from the consolidated cost table (Tab c,kon ) Average costs of charging services for the per time slot (Zf* r ) available power levels LS* r,k to calculate, - from the available level of power levels LS*r,k and the respective length of the time window (Zf* r ) power level-dependent maximum available energy quantities per time window (Zf* r ) to calculate - to create a charging plan for charging the electric vehicle (2) at the charging point (3), in which a charging requirement of the electric vehicle (2) is met by filling it with the energy quantities available in the coupling period with the lowest average costs of the associated charging powers P L is achieved. [12] Electric vehicle (2) according to claim 11, wherein the electric vehicle (2) is arranged to be charged according to this charging plan. [13] System (1) comprising an electric vehicle (2) and a charging point (3) which can be coupled thereto for charging the electric vehicle (1), wherein the system (1) is designed to carry out the method according to one of claims 1 to 10. [14] System (1) according to claim 13, wherein the charging point (3) is a charging point of a public charging station. [15] System (1) according to claim 12, wherein the charging point (3) is a charging point of a property with at least one autonomous energy supply device and the charging point (3) provides a maximum of three power levels, namely per time slot - if there are three power levels (LS* r,1 , LS* r,2 , LS* r,3 ): a first, lowest power level (LS* r,1 ) corresponding to a supply from a non-regenerable surplus, a second, medium power level (LS* r,2 ) corresponding to a supply from a regenerative surplus and a third, highest power level (LS* r,3 ) corresponding to a supply from an energy supply network (6); - if there are two power levels (LS* r,2 , LS* r,3): a first, lowest power level (LS* r,2 ) corresponding to a supply from a regenerative surplus and a second, medium power level (LS* r,3 ) corresponding to a supply from the energy supply network (6); and - if only one power level is available: this power level (LS* r,3 ) corresponding to a supply from the energy supply network (6).

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