DE102009043380A1 - Charging control system for controlling unidirectional charging process of electrical vehicle, has charging control unit receiving predicted charging motion and controlling charging of battery in relation to unidirectional charging motion - Google Patents

Abstract

The system has an electrical vehicle exhibiting an energy storage battery (53) that charges by storing electrical energy. A charging control unit controls the charging of the battery. A computer unit determines a supply power in a network section of an energy network for predicting a charging motion for the vehicle on basis of the determined supply power and for sending predicted load course to the control unit. The control unit is arranged for receiving the predicted charging motion and controlling a charging of the battery in relation to the predicted unidirectional charging motion. An independent claim is also included for a method for controlling a unidirectional charging process of an electrical vehicle.

Description

The invention relates to a charging control system for controlling a charging process of a unidirectional consumer unit.

With the increased integration of renewable energies into the electrical grid, the demand for grid services is increasing. Although the German BDEW (Federal Association of the Energy and Water Management) Medium Voltage Directive envisages that decentralized receivers participate in grid services such as reactive power balancing or the short-term provision of short-circuit power at the medium voltage level, provision of balancing power or the support of individual grid sections can be provided in particular by wind and solar systems however, due to their technical possibilities i. d. R. do not take over.

Electric vehicles include an electric motor for operating the vehicle and an energy source supplying power to the electric motor. The energy source is a primary battery that is rechargeable only once and is replaced by a charged one after discharge, or a (secondary) battery (hereinafter also referred to as a rechargeable battery) that is rechargeable multiple times. A recharge of a battery can be done either inside the vehicle when the vehicle is connected to a power grid, or outside the vehicle, so that an empty battery in the vehicle is replaced by a charged full battery. Vehicles with a rechargeable battery that is charged in the vehicle may have an internal charger or an external charger, eg. B. on a charging station similar to a fuel pump.

A bi-directional electric vehicle ("Vehicle to Grid", V2G) is configured to then charge electrical energy into its battery storage when there is an excess of power available in the electrical grid, as well as to permit discharge from the battery at a time and again to feed back into the electrical network when there is a lack of electrical power in the network. This method is called "bidirectional V2G" in the following. The use of a bi-directional V2G can provide network services such as the provision of control power or the support or relief of congested network sections.

A disadvantage of the bidirectional V2G is the low efficiency of the process, which results from the rectification, charge and change direction. In addition, depending on the type of battery due to battery aging processes caused by charge and discharge z. T. significant cost of storage.

In addition to the above-mentioned disadvantages of the bidirectional V2G (consuming at low efficiency and expensive) consist of the following:
If power is fed into the electrical grid at the low voltage level, as is the case with the bidirectional V2G, the norm must be in Germany VDE 0126 be respected. According to this standard, the mains must be checked for 1 minute before the server can switch to the mains. Should z. For example, if primary control power is provided from bidirectional V2G, it must be ready immediately after the grid frequency change. Thus, in the case of the bidirectional V2G, the feed-in converter must be constantly switched to the grid to supply the primary control power supply VDE 0126 to fulfill. This creates undesirable energy losses.

Insofar as some of the above-mentioned requirements of the BDEW medium-voltage directive also apply to the low-voltage level, there are analogous disadvantages. For example, if reactive power is provided from bidirectional V2G or fed into a short circuit, the network service must be available immediately. Above problem with the VDE 0126 thus occurs here too.

If the inverter is integrated with the drive inverter to regenerate energy in the bidirectional V2G, it has an initial utilization of <1% and correspondingly high losses (see above). However, if the inverter is designed to be smaller than a separate component, the load will increase and the losses will decrease, but the necessary investments in the additional inverters will exceed the expected revenues from the provision of network services.

DE 692 20 228 T2 discloses an electric vehicle and an electrical supply system of a bidirectional V2G method. A charging system for bidirectional energy transfer is described, ie there is a transfer of energy from the power supply to the vehicle battery and in the opposite direction, as z. B. for driving the vehicle (battery to engine) and to recharge the battery (engine to battery) is required. The charging system for the electric vehicle according to DE 692 20 228 T2 has means to control the supply of power to the power supply or the power supply. It is described that the direction or amount of the conducted current may be controlled locally or remotely by a utility such that the injected or ingested power is on a local basis customizable based on the public network. The system thus provides utilities with a large potential, fast response capacity reserve, without any spinning reserve, with little or no investment cost.

The system of DE 692 20 228 T2 has the disadvantage that a complex control is necessary to control the exchange of energy between network and consumer and consumer and network according to the specifications. This involves a complexity and high investment costs for the hardware components, especially in the vehicle. If the battery is charged and discharged more frequently than provided by a manufacturer specified number of charging cycles, an exchange of the battery permanently installed in the vehicle is necessary, resulting in both high installation and acquisition costs.

It is an object of the invention to provide a charging control system which avoids the disadvantages mentioned above.

According to the invention the object is achieved by a charging control system according to claim 1.

The invention is based on the idea that the abovementioned disadvantages are avoided by using a unidirectional vehicle (unidirectional V2G) instead of a bidirectional vehicle. The invention uses the time shift of the charge of batteries in electric vehicles to provide network services such as control power or to relieve individual network sections. In addition, the proposed procedure can create more flexibility for the network operator.

According to the invention is dispensed with the return of energy into the electrical network, which u. a. above problems (consuming, expensive, high energy losses) can be avoided. The solution according to the invention provides for provision of network services without regeneration.

The invention has the advantage that the battery of the unidirectional vehicle according to the invention can be used much longer than is possible in a bidirectional system. In the bidirectional system, the battery is discharged not only by consuming its power but also by discharging operations controlled by the network operator. Such a network operator discharge can be initiated quite a few times a day. In the unidirectional charging system according to the invention, however, the battery is discharged only by consumption of energy. The period of use of the battery of a unidirectional vehicle according to the invention can therefore be increased by a multiple compared to the solution known in the prior art, whereby great cost savings are possible.

The invention has the advantage that no standards for a return of energy from the unidirectional vehicle according to the invention must be met to the network, whereby the use of the vehicle is substantially simplified.

The invention also has the advantage that it is possible to dispense with the integration of charge controllers, drive converters and line feed inverters into a unidirectional vehicle according to the invention, since there is no feedback of energy from the vehicle into the energy grid. As a result, costs are saved both in purchase and maintenance.

Furthermore, the invention has the advantage that an organizational handling of energy trading between energy provider and energy consumer can be significantly simplified. The return of electricity from electrically operated bi-directional vehicles to the supply network requires that private individuals (consumers) become sellers of electricity and thus can not remain consumers. That is to say, these persons would be obliged to pay VAT when purchasing electricity and are not entitled to VAT refunds for the return (sale). This results in economic complications for both parties, which are avoided with the charging control system according to the invention.

Advantages of the invention thus lie in particular in the cost-effective provision of network services, bypassing the described problems of bidirectional V2G. In this way, the unidirectional V2G according to the invention provides an advantageous alternative to z. B. pumped storage power plants available. In particular, it is preferred that the prediction of the load profile according to the invention relates to larger or smaller network sections or even individual consumers in order to provide network services in the sense of the invention.

Preferably, the charging control system further comprises a further electric vehicle with a further battery unit and a further charging control unit, wherein the computer unit for predicting a combined charging load for the electric vehicle and the other vehicles based on the determined consumption power and for sending the predicted combined Ladelastganges to the charging control unit and the others Charge control unit is configured, wherein the charge control unit is configured to receive the predicted combined Ladelastgang and to control the charging of the battery unit according to the predicted combined Ladelastgang, and wherein the further charging control unit is configured to receive the predicted combined Ladelastgang and charging the other Battery unit according to the predicted combined Ladelastgang control. Advantageously, it is achieved that a combined charge cycle for one, two or any other plurality of vehicles can be determined, thereby providing a simpler calculation for predicting the charge cycle than will require the calculation of an individual charge cycle for each individual vehicle. The computational effort can therefore be simplified. The computer unit is preferably configured to group together vehicles, for which a respective charge load has been determined on an individual basis, which is similar or identical to that of the other vehicles, whose combined charge cycle after such a summary is advantageously precise (since the individual load cycles are similar or identical). The combination of individually similar loading operations results in a particularly precise and simple calculation for a combined loading operation of a group of vehicles, which consists of at least two vehicles. It is further preferred that the electric vehicle and the further electric vehicle are consumers in a network section. By forecasting the combined cargo load cycle for these (ie at least two) vehicles, the power consumption for such a network section can be determined particularly accurately and the charging of the battery units of the vehicles can be controlled in accordance with the network section-based predicted combined charge cycle.

The consumption power preferably represents the usage behavior of the vehicle and / or of the further vehicle. The usage behavior of a vehicle group and / or a network section with a vehicle group particularly preferably represents the consumption power of the vehicle group or of the network section with the vehicle group. It is advantageously achieved that the consumption power can be combined individually or determined for a specific network section, wherein the consumption power information can be advantageously used by the energy network operator to provide electrical energy according to the prognosis by controlling the charging process accordingly.

Preferably, the computing unit is configured to output a positive control signal to the charging control unit to provide the grid section with positive control power, and the charging control unit is configured to throttle the charging power of charging the battery pack according to the predicted charging load according to the positive control signal. Such a charging control system has the advantage that the computer unit has an influence on the charging power of the charging of the battery unit. That is, if power is required in the corresponding network section, the computer unit, which is preferably a central unit, preferably decentralized to the charging control units communicate that the charging power of the charging of the battery unit is to throttle. In this way, the network section advantageously provides positive control power. Separate feeding of energy into the network section can thus be avoided.

Preferably, the positive control signal has time information representing a time or period, and the charge control unit is configured to throttle the charging power of charging the battery unit according to the predicted charge duty according to the positive control signal during the time or the period. For example, a time may be that time in which typically (ie, typically for a weekday or weekend), a lot of energy is required in the network section, such as 6:00 pm because many people are returning from work and driving the vehicle at this time couple the network section. A period of time is preferably a period of several hours or several days, e.g. For example, it is the period from 6:00 pm to 11:00 pm, because during this period a particularly large number of vehicles are connected to the network section and the general energy consumption during this period is particularly high. Such time or such period may thus preferably be a fixed time or a fixed period. It is also preferable that the time or period is relative. For example, a time information representing a relative time is "in one hour", which means that after one hour starting to receive the time signal, the charge duty is to be throttled. The indication of a relative period preferably means a period of several hours and / or days from receipt of the signal of the time information.

Preferably, the predicted charge cycle includes minimum information representing a minimum load profile for providing positive control power to the grid section, and the charge controller is configured to control the charging performance of charging the battery pack between the predicted charge cycle and the minimum charge cycle. By defining the minimum charging load is advantageously achieved that the minimum Ladelastgang, which may be predetermined, for example, by characteristics of the battery unit of the vehicle and / or the network section is not exceeded. In other words, it a kind of buffer is provided above which the charge is carried out. It is thus advantageously ensured that the battery unit is always charged in accordance with at least the minimum charging load and the network section a corresponding amount of energy is provided.

Preferably, the computer unit is configured to output a negative control signal to the charging control unit to provide the grid section with negative control power, and the charging control unit is configured to increase the charging power of charging the battery pack according to the predicted charging load according to the negative control signal. By means of such an embodiment is achieved according to the invention that the battery unit of the vehicle (or the battery units of the vehicles) are charged with increased charging power, for example, if particularly much energy is present in the network section. On separate energy storage systems, which would have to be maintained for example by the energy grid operator, can be dispensed with so advantageous. It is also advantageous that the preferably central computer unit is able to control the preferably decentralized units of the vehicles or the battery units and to adjust their charging power based on the consumption power in the network section of the power grid.

Preferably, the negative control signal has time information representing a time or a period, and the charge control unit is configured to increase the charging power of charging the battery unit according to the predicted charge duty according to the negative control signal during the time or the period. For this embodiment, the analog applies as already explained above with reference to the embodiment of claim 5, wherein only the sign of the control signal or the throttling is to be replaced by an increase of the charging power.

Preferably, the predicted charge load path has maximum information representing a maximum charge load for providing negative control power to the grid section, and the charge control unit is configured to control the charge power of charging the battery pack between the predicted charge cycle and the maximum charge cycle. Analogously, as explained above with reference to the embodiment of claim 6, the embodiment of claim 9 has the advantage that a maximum charging load of the charging power of the battery is not exceeded. The maximum charging load is preferably determined by characteristics of the battery unit. Preferably, the maximum charging load is determined by how much energy is to be provided in the network section despite maximum charging power of the one (or more) vehicle. It is held on the part of the network section a kind of energy buffer, which is activated when the charging power is reduced compared to the maximum charging power.

Preferably, the predicted loading operation is a reflection of the determined consumption power in order to smooth a load peak in the network section. A calculation of the predicted charge load cycle by mirroring the specific consumption power is a particularly simple calculation method by which the computing time and the computational complexity of the computing unit can be simplified. Furthermore, such a calculation offers a particularly good approximation for smoothing the load peaks in the network section in order to provide the most uniform possible flow of energy in the network section, whereby the connection of additional power plants or the provision of storage units can be spared.

Preferably, the charging control unit is configured to perform the charging of the battery unit with at least a safety charging performance. The safety charging power is preferably smaller than the charging power of the minimum load gear. Advantageously, it is achieved that the battery unit is always charged at least with the safety charging power regardless of the power consumption in the respective network section to ensure that the battery unit has a correspondingly predetermined minimum charge. This is advantageous because the user of the vehicle unit is guaranteed so that the vehicle can always cover a path corresponding to the safety-charged battery unit.

In a further aspect, the invention relates to a method for controlling a unidirectional charging of an electric vehicle, comprising the steps of:
Providing electrical energy in a power grid, determining a power consumption in a network section of the power grid, predicting a charging load for the electric vehicle based on the predetermined consumption power, connecting the electric vehicle to the power grid, wherein the electric vehicle, a battery unit for charging by storing electrical Having energy, and controlling the charging of the battery unit of the electric vehicle according to the predicted unidirectional Ladelastganges.

Particularly preferred is a method of using one (or more) unidirectional V2G according to the invention for providing secondary control power:
The battery charge of several electric vehicles from the electrical network is controlled by a central office of the power grid operator. By the Knowing the use of electric vehicles, a load profile for the cargo can be predicted. The central office is to provide positive secondary control power the signal to deviate from the predicted load cycle, so to delay the charge and thus at the desired time to reduce the charging power to provide positive secondary control power, or increase the charging power to provide negative secondary control power. The method preferably also works analogously for the other control power types and for the support of distributed network sections.

By extending the method, in addition to providing the network services mentioned above, peak loads in network sections can also be reduced. For this purpose, the planned load cycle is set so that only the load peak from the network is taken to the peak load that including a guard band, the entire predetermined positive control power can be provided.

Alternatively or additionally, the electric vehicle according to the invention can increase the safety band.

Alternatively or additionally, it is further preferred that the electric vehicle according to the invention dispenses with the safety strap and instead carries out forced charging. In such a case, the electric vehicle according to the invention would be of limited use for the driver and the driver would have to follow the forced charging plan of the electric vehicle according to the invention.

The invention will be explained below with reference to exemplary embodiments, wherein

1 illustrates a unidirectional charge both regulated and unregulated;

2 a schematic representation of the charging power and the unidirectional provision of positive and negative control power illustrated;

3 shows a further schematic representation of the charging power and unidirectional provision of positive and negative control power, and

4 a schematic representation of the network coupling of electric vehicles according to the invention shows.

The connection of electric storage batteries from electric vehicles to the power supply network and their infrastructures for "intelligent" recharging of the batteries open the possibility of targeted control as needed. In particular, for the network operators, the primary, secondary control and minute reserves are important for ensuring network stability. If the charging process according to the invention of the batteries, d. H. Battery units of electric vehicles, centrally controlled by a "Decentralized Energy Management System" (DEMS), so the charging current can be arbitrarily "metered" - driven up and down - so as to create "virtual" primary and secondary control performance. It surprisingly turns out that this technique of demand side management (i.e., without backfeed) for an electric vehicle is economically and technically superior to regenerative storage (i.e., bidirectional). The electric vehicle according to the invention, which is based on demand side management, is referred to below as "unidirectional V2G".

The term "primary control power" is used in the sense of this description as follows. Available primary control band: The primary control power provider preferably ensures that the offered control range per unit (TE) is at least ± 2% of the nominal power of the TE but at least ± 2 MW, above the measurement tolerances and above the sensitivity range of its equipment and metrologically with the existing instrumentation is demonstrable. The primary control band of ± 2 MW usually can not provide a single electric vehicle. Here, it is preferable to define the sum of the electric vehicles connected to the grid in a network section as a technical unit. Time Availability:
The offered primary control power should be available over the entire offer period (time availability is 100%). A large part of the private electric vehicles is not available during the day in the network, or at some point is fully charged. At these times, the agreed control power is not completely retrievable in both directions (ie positive / negative primary control power). A good mix of users (eg, early-service, late-shift, caretaker) in a "regular fleet" is preferred here.

The term "secondary control power" is used in the sense of this description as follows. Available secondary control band per technical unit: Technical units to participate in the secondary control should have at least one secondary control band of ± 30 MW. The two directions (positive and negative secondary control power) can be provided and provided in different TEs (see above). Application availability: Due to the design, a distinction must be made between hydraulic, thermal and other units: Pumped storage systems (daily storage) must at least be used for 4 Hours are available with the full contracted balancing power; Hydraulic annual storage must be able to operate indefinitely in individual time slices (an individual, maximum possible total work volume can be agreed here); Thermal and other technical units must be able to perform the contracted secondary service indefinitely over the period offered (100% working availability). The unidirectional V2G according to the invention behaves approximately like a pumped storage power plant (daily storage). The memory is limited. Therefore, the unidirectional V2G according to the invention may preferably be sorted into this class. Time availability: The technical units should have a time availability of at least 95%. Partially failed secondary control power can be replaced by minute reserve after consultation with the transmission system operator (see above). Frequency of use: Technical units operating under the secondary controller should be able to continuously provide the control power demanded by the central secondary controller. This also applies in the case of the rule direction reversal (see time availability).

The term "minute reserve" is used in the sense of this description as follows. In the minute reserve, there is the concept of "pooling". This means that several power plants of possibly different operators within a control area may participate together in a prequalification. This corresponds to the procedure which is necessary for a prequalification of a unidirectional V2G according to the invention, if it is not possible to formally combine several electric vehicles into one technical unit. The minute reserve indicates the "prequalification of plants in the medium-voltage / low-voltage grid" (in particular emergency power plants). Work Availability: The availability of the offered minute reserve must be 100% over the entire offer period. Possible limitations in the working capacity of the individual technical units for the provision of minute reserve are to be mentioned (eg for pumped storage power plants or disconnectable loads). Technical units whose working capacity is not 100% can only be prequalified within a minute reserve pool (see above). The possibility of pooling possibly also with other power plant and load types is particularly advantageous for the unidirectional V2G concept according to the invention. Time availability: The specified minute reserve power must be kept in full throughout the entire offer period and be retrievable (time availability 100%). Possible restrictions in the time availability of the individual technical units for the provision and provision of minute reserve, which are less than 24 hours, should be mentioned (eg maximum operating time of a system). This too is particularly advantageous in the case of the unidirectional V2G according to the invention. It is advantageous in this context to make accurate predictions about the availability of battery storage on the grid.

For the above requirements, it is preferable to meet special requirements of the transmission system operator responsible for the area where the power plant capacity or controllable loads are to provide the control power.

A method in which the power is shifted without significant impairment of the function of the vehicle so that power is taken from the electrical network, if there is an excess of power in the grid, but the power consumption of the vehicle is throttled, if a lack of electrical Performance in the network is referred to below as "Demand Side Management".

V2G ("Vehicle to Grid", translated into German as "vehicle to the grid") is a concept for coupling electric and hybrid vehicles with battery storage devices to the electrical grid. The coupling takes place in such a way that network services such as control power and reactive power compensation can be provided or load smoothing can be provided by the use of the battery storage in the electric vehicles. The conventional V2G concept envisages that e-mobiles take power from the grid and also feed it back in times of high network load. The present invention is a demand side management system and provides significant technical, economic and legal benefits.

The conventional bi-directional V2G requires around 129,000 e-mobiles in order to display the secondary control line that is proportionally generated in the EWE grid area. This is approximately 12% of the private car fleet of EWE household electricity customers (as of February 2009). The bottleneck of bidirectional control power delivery is not the available inverter power and not the size of the available memory, but the energy consumption of e-mobile, which must reach a certain size in order to safely dissipate the negative secondary control energy.

If the unidirectional V2G according to the invention is used, approximately 376,000 e-mobiles or 34% of the private passenger car fleet of EWE household electricity customers are needed to provide the proportionate secondary control power in the EWE network area. Again, the "traded energy" of electric vehicles (electric vehicles) is an important factor.

But since a fed back kWh bidirectional V2G with about 0.45 EUR to book and the unidirectional V2G in comparison can be used almost free of charge, as well as numerous technical, legal and billing problems in bidirectional V2G occur, the unidirectional V2G of significant advantage , In addition, the unidirectional V2G in addition to the secondary control power easily provide primary control power, which is the case with the bidirectional variant only with restrictions.

As important as the provision of control power is that the "virtual" electrical storage of the electric vehicle according to the invention is capable of receiving power from sustainable energy technologies, wind and solar power whenever they arise. This can even be done by slightly increasing the number of embedded e-vehicles in parallel with the provision of control power. A procedure is presented below. In this constellation, a secure and sustainable coverage of the electricity needs of e-mobility is achieved solely through the "unsteady" wind energy in technical interaction with the "virtual" electrical storage.

Decisive for the dynamic integration of electric vehicles in the existing power grids are communication technologies that make it possible to uniformly address distributed, distributed consumers from a central location in a diverse infrastructure. A "decentralized energy management system" (DEMS) as the headquarters of a virtual power plant is preferred for the respective region in order to be able to introduce these technologies. The DEMS takes over the optimization of the charge (and with the bidirectional V2G also the discharge) of the decentrally distributed battery storage of e-mobiles. In addition to the spatial distribution of the memory over the network area, the storage density shift over the course of the day is predicted and integrated into the network calculations. Thus, in the unidirectional V2G, a stable operation of critical line routes can be ensured despite the larger amount of energy to be delivered due to the E-Mobile.

According to the invention, the use of information and communication technology (ICT) on the one hand improves forecasts of decentralized, stochastic feed-in. On the other hand, network management is optimized through improved power plant deployment planning. The focus is on the Smart Grid, in which not only power plants are intelligently controlled, but also actively influenced by consumers through demand side management.

The information and communication technology ICT in the electricity sector is explained below.

Power electronic elements for network control (eg V2G) are controlled in order to be able to meaningfully carry out their function of network control. Networks, where decentralized producers and consumers are intelligently controlled to ensure a high level of security of supply and quality of supply, are called smart grids. Here, a distinction is made between central and decentralized control. In the central control, all information of the decentralized producers, including the network status, is sent to a central trust center, which bundles the information, evaluates it and returns commands for suitable measures to the decentralized energy feeders. This centralized control includes the Virtual Power Plant or the Decentralized Energy Management System (DEMS).

This contrasts with decentralized control, in which every decentralized energy feeder decides according to previously defined rules which reaction would be suitable for the current situation.

Both currents are promoted by the increasing use of the smart meter, a digital energy meter that can be remotely read in addition to data logger functions in some cases and possibly make switching operations. The use of the smart meter is z. This is supported, for example, by the European Commission in order to give the electricity customer more transparency in his electricity bill at shorter intervals. The goal is to stop the user of the power supply by means of short-term feedback on his energy usage behavior for the efficient use of electrical energy. The basis of the smart meter provides a basis on which a communication structure for a smart grid can be built.

Active load management (or Demand Side Management (DSM)) refers to the control of electricity demand in electrical consumers in industry, commerce and private households. Bottlenecks in power generation, such as by the failure of a power plant, or by high demand, for. B. at peak load in the midday, can be switched off by remote control single large and many electrical consumers and again. However, this option is limited to devices and machines that can be turned off for a period of time without the need for user / owner approval. For this purpose, it should first be contractually regulated which devices can be switched off and how long. In return, the customer receives one Discount on the general electricity tariff. Consumers who are (vital) important for safety, such as As alarm systems, emergency lighting or computer, must not be turned off.

According to the invention, it has been recognized that unidirectional electric vehicles can provide network services for the energy industry. In the unidirectional vehicle to grid according to the invention, the charging power is adjusted by regulation. According to the unidirectional vehicle to grid, the battery, i. H. the battery unit, the electric vehicle via a unidirectional charge controller connected to the network. Thus, electrical power can only flow from the grid to the battery, but not be fed back into the grid. The charging power is determined firstly by the battery management and / or secondly by the virtual power plant. By shifting the battery charge over times can be selected at which the electrical energy from the grid is favorable. In addition, control power can be provided by deliberately deviating from a predicted charge cycle.

A virtual power plant is an interconnection of small, decentralized power plants, such as electric vehicles according to the invention, photovoltaic systems, small hydropower plants and biogas plants, but also small wind turbines and combined heat and power plants of smaller power to a composite, which are controlled together. As micro-CHPs become more widely used to power buildings, the concept of the virtual power plant is becoming more and more obvious, with additional economic benefits (eg generation of peak load power and supply of control energy) through coordinated feed-in behavior. Thus, a mini CHP can produce the power mainly to the power peak and buffer the temporarily excess heat in a heat storage. The owner of a decentralized system should allow for this purpose interventions by the operator of the virtual power plant in his plant control, which could lead to considerable acceptance problems, especially in private households.

Due to their structure with small producers, virtual power plants can not completely replace the existing network structures with large central power plants.

Rather, the concept of the virtual power plant opens up the possibility of supplementing and optimizing the existing structures of the energy supply system.

In addition to acceptance problems, among other things, the cost of communication and the cost of the central control of the virtual power plant in comparison to the uncoupled operation of decentralized feed systems an obstacle to the spread of virtual power plants. Therefore, virtual power plants are preferred in which the individual decentralized Einsgeiser not over have a constant information technology coupling.

If generator networks and load networks are interconnected, an intelligent controller can achieve to compensate for power peaks by demand side management of the electric vehicle according to the invention, in order subsequently to cover the remaining power remaining requirements cost-effectively from the range of the connected generator networks.

Virtual power plants use synergy effects that result from the interconnection of individual power plants. These effects include, for. As the load distribution, so the coverage of peak loads that would overwhelm a single power plant, by adding additional producers. This also includes the compensation of location or weather-related disadvantages. Because you have base load power plants such. B. nuclear and lignite power plants for economic reasons usually does not shut down at night, the caching of night electricity in storage power plants is a conventional technique.

For example, a wind farm, a photovoltaic power plant and an energy store (eg pumped storage power station or batteries in electric vehicles according to the invention) could be combined to form a virtual power plant: If there is little wind, the solar power plant may be feeding large amounts of electricity. If no sun is shining, it may be able to supply the wind power plant. If the sun shines strongly and there is a lot of wind blowing, excess energy can be stored in the pumped storage tank or electric vehicle according to the invention. If no wind blows and no sun shines, the pumped storage plant returns the energy. The more different individual power plants and power plant types are combined, the higher the synergy effect and thus the overall efficiency of the virtual power plant.

• 1. Beteiligung an Primär-, Sekundärregelung und Minutenreserve durch Erhöhung oder Reduzierung der Batterie-Ladeleistung und somit der Netzbelastung
• 2. Ggf. Blindleistungsbereitstellung im Netz durch aktive Gleichrichtung

Possible contributions of the unidirectional V2G according to the invention for network stabilization without integration of inverters in the interconnected network are:

• 1. Participation in primary, secondary control and minute reserve by increasing or reducing the battery charging power and thus the network load
• 2. If necessary Reactive power supply in the network through active rectification

• – Einhaltung der VDE 0126 : Da keine Rückspeisung stattfindet, muss auch keine Norm für die Rückspeisung eingehalten werden.
• – Bei der Rückspeisung von Strom aus E-Mobilen in das Versorgungsnetz wird die Problemstellung aufgeworfen, dass Privatpersonen (Verbraucher) nicht zu Verkäufern des Stroms werden können und somit Verbraucher bleiben. D. h. diese Personen wären bei dem Kauf von Strom verpflichtet, Mehrwertsteuer zu zahlen und bei der Rückspeisung (dem Verkauf) nicht zur Mehrwertsteuererstattung berechtigt.

With this variant, the following disadvantages of known systems can be circumvented:

• - Compliance with VDE 0126 : Since no feedback takes place, no standard for the feedback must be observed.
• - The return of electricity from electric vehicles to the supply network raises the problem that individuals (consumers) can not become sellers of electricity and thus remain consumers. Ie. these persons would be obliged to pay VAT when purchasing electricity and are not entitled to reimbursement of VAT for the return (sale).

• – Blindleistungsausgleich: Ist möglich, insbesondere wenn aktive Gleichrichtung integriert ist;
• – Primärregelung: Ja, möglich;
• – Sekundärregelung: Ja, möglich;
• – Minutenreserve: Ja, möglich;
• – Regelleistungsband: Band zwischen maximaler Ladeleistung und keiner Ladung, primär limitiert durch Energieverbrauch und Nutzeranforderungen;
• – Vorschlag eines Regelalgorithmus (Beispiele: kontinuierlicher Ladestrom, der zur Bereitstellung von Regelleistung gedrosselt oder erhöht werden kann);
• – Stützung von Abschnitten des Verteilnetzes: Ja, passiv durch Demand Side Management.

The unidirectional network coupling according to the invention of electric vehicles has the following characteristics:

• - Reactive power compensation: Is possible, especially if active rectification is integrated;
• - primary regulation: yes, possible;
• - secondary regulation: yes, possible;
• - Minute reserve: Yes, possible;
• - Control power band: Band between maximum charging power and no charge, primarily limited by energy consumption and user requirements;
• - propose a control algorithm (examples: continuous charging current, which can be throttled or increased to provide control power);
• - Support of sections of the distribution network: Yes, passively through demand side management.

• – DEMS 11 (SCT, SCP): Das Dezentrale Energie Management System ist die Zentrale des Virtuellen Kraftwerks. Von hier aus werden Befehle an die Mikrokraftwerke geschickt, so dass das Ladegerät „weiß” wann es wie stark laden soll.
• – Die Stationäre Ladestation 12 steht für ein physisches Gerät, das außerhalb des E-Mobiles an einem festen Ort steht und die Aufgabe hat, die Batterien zu laden. Dies kann durch eine Batteriewechselstation oder eine Stromtankstelle realisiert werden. Die stationäre Ladestation kann eine Smart Metering Einheit und eine Ladefreigabeeinheit 13 aufweisen.
• – SMet-E 51: Die Smart Metering Einheit misst die elektrische Leistung, berechnet die übertragene Energie und stellt sie als digitalen Wert zur Verfügung.
• – Leistungselektronik 52: Der Umrichter dient der Gleichrichtung zur Batterieladung. Zusätzlich kann die Leistungselektronik das Steuermanagement und die Bordelektronik aufweisen.
• – Energie-Speicher Akku 53: Es gibt verschiedene Ausführungsformen der Anordnung des Akkus: im E-Mobil zur Ladung über einen Netzstecker; wird die stationäre Ladestation zur Batterietauschstation, kann der Akku dem E-Mobil entnommen, in die Batterietauschstation mechanisch eingefügt und dort geladen werden.
• – Embedded System, Kommunikation, IP 51: Dies ist die Kommunikationseinheit im Fahrzeug, die die Verbindung zwischen der Nutzerschnittstelle, der Ladestation und dem Energiemanagement übernimmt.
• – MSR-Technik 54: die Mess-, Steuer- und Regeltechnik stellt Messwerte aus dem Fahrzeug zur Verfügung und übernimmt Steuer- und Regelungsaufgaben im Fahrzeug.
• – Nutzerschnittstelle 55 (Design, Funktionen): Die Nutzerschnittstelle dient der Kommunikation zwischen Technik im Fahrzeug und Nutzer. Sie kommuniziert Zustände im Fahrzeug und im elektrischen Netz mit den Fahrer (aktuell verfügbare Reichweite, Preis pro kWh bei bestimmten Laderandbedingungen, etc.). Zudem dient sie als Eingabetool für den Nutzer, um optional mit den Netzbetreiber zu kommunizieren.
• – Energiemanagement 56: Das hier adressierte Energiemanagement sorgt für geordnete Energie- und Leistungsflüsse zwischen den Komponenten im E-Mobile. Diese können sein: Super-CAPS, Akku, E-Antrieb, Ladegerät (230 V) 59 etc.
• – Super-CAPS 57: Super-CAPS sind Kondensatoren, die große Leistungen schnell und mit gutem Wirkungsgrad aufnehmen können. Batterien sind besser geeignet, um vergleichsweise geringe Leistungen, aber große Energiemengen aufzunehmen.
• – E-Antrieb 58: Antrieb, der das E-Mobil elektrisch in Bewegung versetzt.

An embodiment of a unidirectional vehicle to grid according to the invention 50 is in 1 represented and with the power supply network 10 (eg as a WAN communication network). A unidirectional vehicle to grid according to the invention has, for example, the following units, which may be assembled differently in different embodiments:

• - DEMS 11 (SCT, SCP): The Decentralized Energy Management System is the headquarters of the Virtual Power Plant. From here commands are sent to the micro-power stations, so that the charger "knows" when it should charge as much.
• - The stationary charging station 12 stands for a physical device that is located outside the electric vehicle in a fixed location and has the task of charging the batteries. This can be realized by a battery changing station or a charging station. The stationary charging station may be a smart metering unit and a charge release unit 13 exhibit.
• - SMet-E 51 : The smart metering unit measures the electrical power, calculates the transmitted energy and provides it as a digital value.
• - Power electronics 52 : The inverter rectifies the battery charge. In addition, the power electronics can have the control management and the on-board electronics.
• - Energy storage battery 53 : There are various embodiments of the arrangement of the battery: in the electric vehicle for charging via a power plug; If the stationary charging station becomes a battery replacement station, the battery can be removed from the E-mobile, mechanically inserted into the battery replacement station and charged there.
• - Embedded system, communication, IP 51 : This is the communication unit in the vehicle, which takes over the connection between the user interface, the charging station and the energy management.
• - MCR technology 54 : The measuring and control technology provides measured values from the vehicle and takes over control and regulation tasks in the vehicle.
• - User interface 55 (Design, Functions): The user interface is used to communicate between technology in the vehicle and users. It communicates conditions in the vehicle and in the electrical network with the driver (currently available range, price per kWh for certain charging conditions, etc.). In addition, it serves as an input tool for the user to optionally communicate with the network operator.
• - Energy management 56 : The energy management addressed here ensures orderly energy and power flows between the components in the e-mobile. These can be: Super CAPS, battery, electric drive, charger (230 V) 59 etc.
• - Super CAPS 57 : Super CAPS are capacitors that can absorb high power quickly and with good efficiency. Batteries are better suited to absorb comparatively low power but large amounts of energy.
• - Electric drive 58 : Drive that electrically sets the electric vehicle in motion.

• 1. Kommunikation zwischen dem DEMS und der Smart Metering Einheit.
• Dieser kann z. B. über Powerline Communication oder das Mobilfunknetz realisiert sein.
• 2. Kommunikation zwischen der Smart Metering Einheit in der Ladestation und dem Embedded System im Fahrzeug. Diese kann je nach Komplexität der übertragenen Daten durch Powerline Communication oder eine spezielle Datenleitung realisiert werden.
• 3. Kommunikation zwischen der Nutzerschnittstelle und dem Embedded System. Diese kann z. B. über den CAN Bus des Fahrzeugs realisiert werden.
• 4. Kommunikation zwischen dem Embedded System und dem Energiemanagement. Dies kann ebenfalls z. B. über den CAN Bus Realisiert werden.

The components are in 1 shown dashed arrows, which are for the data transmission, or communication, between technical components. The arrows are numbered and mean:

• 1. Communication between the DEMS and the smart metering unit.
• This can z. B. be realized via Powerline Communication or the mobile network.
• 2. Communication between the smart metering unit in the charging station and the embedded system in the vehicle. Depending on the complexity of the transmitted data, this can be realized by Powerline Communication or a special data line.
• 3. Communication between the user interface and the embedded system. This can, for. B. be realized via the CAN bus of the vehicle.
• 4. Communication between the embedded system and the energy management. This can also z. B. be realized via the CAN bus.

• I. Ladung der Batterie über ein 230 V einphasiges Ladegerät 59 am Netz.
• II. Leistungsaustausch zwischen stationärer Ladestation 12 (z. B. an ~ 400 V Stromnetz) und Leistungselektronik im Fahrzeug.
• III. Fahrzeuginterner Leistungsfluss zu und von den Batterien und ggf. den Super-Caps und dem aktiven Gleichrichter 60.
• IV. Leistungsfluss von den Batterien/den Super Caps zum elektrischen Antrieb des Fahrzeugs. Bei der Fahrzeugbremsung wird die Bremsenergie zurück in die Batterien/die Super-Caps gespeist (Rekuperation, angedeutet in 1 durch Pfeil A).

In addition, in 1 To see arrows, which stand for the power transmission, or the energy flow. These are numbered with Roman numerals:

• I. Charging the battery via a 230 V single-phase charger 59 on the net.
• II. Power exchange between stationary charging station 12 (eg ~ 400 V power supply) and power electronics in the vehicle.
• III. In-vehicle power flow to and from the batteries and possibly the super-caps and the active rectifier 60 ,
• IV. Power flow from the batteries / super caps to the electric drive of the vehicle. During vehicle braking, the braking energy is fed back into the batteries / super-caps (recuperation, indicated in 1 by arrow A).

1 on the one hand shows a communication structure of the units 11 . 13 . 51 . 55 and 56 , and on the other hand, an energy flow structure of the units 53 . 57 . 58 . 59 and 60 ,

The vehicle of the 1 communicates directly with the DEMS z. Eg via Power-Line Communication. In order to find out with which meter the charging energy is charged, the socket identifies itself with the E-mobile, which preferably passes on its own IP with the IP of the socket to the DEMS.

In 1 Both the regulated (400 V) unidirectional charge and the unregulated (230 V) unidirectional charge are shown.

The technical unit for communication between the vehicle and the network can be arranged in the vehicle or at the external charging station. The arrangement in the vehicle has the advantage that the charging station network can be inexpensively removed. The arrangement at the external charging station has the advantage that billing and communication via proprietary channels of the respective network operator can take place; furthermore, double settlements do not occur.

The task of the communication unit is to carry out the data exchange between the vehicle / battery and the interconnected network / grid operator, to avoid conflicts with existing infrastructure for power supply and billing, and to perform switching operations according to specifications, to which it has received commands from the battery management or the grid operator, as well as switching operations decentralized decisions.

The in-vehicle communication unit between network and vehicle or in-vehicle power electronics has in the inventive unidirectional network coupling (with active or passive rectifier) has the advantage that it can be used in small numbers technically useful, since they can be used anywhere where a signal from the network operator available is. Furthermore, there is less effort for hardware development and a medium standardization requirement in cooperation with several e-mobile manufacturers. The system can also be retrofitted and used economically in large quantities.

The use of an external communication unit between network and vehicle or external power electronics (charging station) has in the inventive system of unidirectional network coupling (with active or passive rectifier) has the advantage that a particularly low cost of hardware development is required. Depending on the design, there is a low to very low standardization requirement in cooperation with several e-mobile manufacturers. Also, the system is easy to retrofit and economical in large quantities.

• 1. die zu beziehende Leistung,
• 2. die Bereitstellung von Regelleistung über bis zu 4 Stunden,
• 3. die Bereitstellung eines Dauerlastbandes über 24 Stunden.

The unidirectional provision of secondary control power according to the invention is considered below by way of example. The consideration is under the following three boundary conditions:

• 1. the service to be purchased,
• 2. the provision of control power for up to 4 hours,
• 3. the provision of a continuous load band over 24 hours.

The following calculations are based on the assumption that approximately 2,130,000 people are connected to the electricity grid of EWE AG (as of February 2009). This is about 2.6% of Germany's 82,127,000 inhabitants.

The share of 2.6% in the total electricity consumption, or the number of inhabitants, is related to the total secondary control capacity in Germany. 2.6% of 3,000 MW of positive secondary control capacity correspond to 78 MW and 2.6% of 2,400 MW of negative secondary control capacity are 62.4 MW, which can be assumed purely mathematically for the EWE area.

These amounts of the proportion of secondary control power generated in the EWE sector could theoretically be provided by energy stored in the batteries of electric vehicles. The number of vehicles required for this can be found on the as a basis for the scenario of a conventional bidirectional and then a unidirectional connection of e-mobiles to the network. In both scenarios it is assumed that the vehicles are connected to three-phase 16 A / 230 V sockets and that the power electronics of the vehicles are also designed for these values. This results in a connected load of approx. 11 kVA (calculated from 3 · 16 A · 230 V) per vehicle.

It can be calculated that an average car drives about 65 minutes per day and thus can not be available on the network. Approximately 25% of the 65 minutes travel time fall in the period of 15 clock and 19 clock. Thus, in these 4 hours twice as many cars are moved as the average of the rest of the day. Even during this critical period, the required balancing power must be fully available. Therefore, the number of vehicles needed to provide secondary control power is calculated precisely for this period. Within the four hours between 15 and 19 o'clock an E-Mobil drives on average 25% of 65 minutes = 16,25 minutes. The remaining period of the considered 4 hours, which corresponds to approximately 93.23% (calculated from 223.75 min / 240 min), is pure life.

The connection duration of the car to the interconnected network during the service life depends primarily on the quantity and distribution of the available charging stations in the network area, the financial incentive for the vehicle user to couple his vehicle to the interconnected grid and the coupling effort required by the driver. It is assumed below that there is a well-developed infrastructure at charging stations and therefore the vehicles are coupled to the grid for 80% of their service lives. Thus, within the 4 critical afternoon hours on average about 75% of the vehicles (80% of the above calculated 93.23%) are available on the grid.

Calculations, which will not be discussed in more detail in the context of this application, show that 128,872 electric vehicles are needed to provide 2.6% of the secondary control power required in Germany when the conventional bidirectional vehicle to grid is used. The required number of vehicles with controlled unidirectional connection is calculated as follows:
Immediately after using an e-mobile, its battery is recharged from a power outlet. For the regulated unidirectional connection of electric vehicles to the grid, the driving power distribution over the day and thus the charging of the batteries with unregulated charging for each hour of the next day can be predicted. Thanks to the battery storage, the charging period can be postponed and thus the charging load can be consciously influenced. Thus, despite a deviation of the actual from the predicted driving power distribution over the day of the predicted load cycle can be maintained. In addition, it is possible to deliberately deviate from the predicted load profile and to make control power available if required.

Since in the unidirectional operation of e-mobile is not possible to feed power back into the network, from the point of view of e-mobile users, the possibility of providing positive secondary control power is their decrease, ie the battery charge from the network to Restrict network operators at desired times (the reduction of power consumption is equivalent in the view of the network operator to the provision of additional power). This means that a constant charging power of 78 MW should be available through e-mobiles in order to be able to provide (switch off) the positive balancing power proportionately calculated for the network area of EWE at any time.

In addition, the inclusion of the negative secondary control power of 62.4 MW at times desired by the grid operator must be allowed.

2 shows a schematic and time-dependent depiction of the unidirectional vehicle to grid charging power P _L and unidirectional provision of positive secondary control power A and negative secondary control power B. The charging power curve between A and B denotes the predicted charging load D.

The provision of negative or positive control power requires an additional charging power of up to 62.4 MW for up to 4 hours each and a reduction of the charging power by up to 78 MW. A safety band C for an urgent load of up to 30% (equivalent to approximately 42 MW) of the participating e-mobile proved to be advantageous.

A_MG

benötigte Gesamtanzahl E-Mobile

L_SRP

positive Sekundärregelleistung [MW]

L_SRN

negative Sekundärregelleistung [MW]

L_AM

Anschlussleistung pro E-Mobil [kW]

In the in 2 It is assumed that by temporal shifts of the charging processes, a constant total charging power with the illustrated deviations for positive and negative control power can be achieved. Due to the planned safety band of 30% of the total charging capacity, the constant charging charge is still guaranteed when electric vehicles with a cumulative charging power of up to 42 MW carry out a fast charge at the same time and thus can not be switched off as part of the reserve power supply. The entire fleet of e-mobiles must be able to charge at any time with a capacity of 78 MW, which can be completely shut down for up to 4 hours if required to provide positive control power as well as an additional 62.4 MW of charging power for up to 4 hours to deliver negative control power. Assuming an 11 kW connection as well as an afternoon period from 3 to 7 pm, in which only 75% of e-mobiles are available for network regulation, the following total number of e-mobiles is required: A _MG = (L _SRP + L _SRN ) / (0.75L _AM ) (1) With

A _MG

required total number of e-mobiles

L _SRP

positive secondary control power [MW]

L _SRN

negative secondary control power [MW]

L _AM

Connected load per electric vehicle [kW]

This results in a required total of 17,019 electric vehicles.

S_EP

erforderlicher Energiespeicher zur Bereitstellung positiver Regelleistung [MWh]

L_SRP

positive Sekundärregelleistung [MW]

t_L

Ladezeit [h]

In addition to the power delivery shown above, the required energy storage should be available. This would at any time in addition to the predicted load, the following free storage capacity include: S _EP = L _SRP t _L (2) With

S _EP

Required energy storage to provide positive control power [MWh]

L _SRP

positive secondary control power [MW]

t _L

Charge time [h]

S_EC

erforderlicher Gesamtenergiespeicher der E-Mobile [MWh]

L_SRP

positive Sekundärregelleistung [MW]

L_SRN

negative Sekundärregelleistung [MW]

t_L

Ladezeit [h]

For a positive secondary control power of 78 MW and a charging time of 4 hours, the total energy storage required is 321 MWh. At the same time, the memory is regularly charged with at least 62.4 MW in order to be able to provide the negative control power at any time. S _EC = (L _SRP + L _SRN ) t _L (3) With

S _EC

required total energy storage of e-mobile [MWh]

L _SRP

positive secondary control power [MW]

L _SRN

negative secondary control power [MW]

t _L

Charge time [h]

In total, for a total regulated capacity of 140.40 MW, composed of negative and positive balancing power, for a period of 4 hours, free storage capacity of at least 561.6 MWh should be available at all times.

A_MG

benötigte Gesamtanzahl E-Mobile

S_EC

erforderlicher Gesamtenergiespeicher der E-Mobile [MWh]

S_EM

Energiespeicher pro E-Mobil [kWh]

If one wants to dimension the maximum charge state of the average E-Mobils on 80% SOC, then the last 20% of the available memory must have a capacity of 561.6 MWh. Assuming as above that E-Mobile have 30 kWh of memory content and 75% of the network is available, then the total number of e-mobiles required is calculated as follows: A _MG = S _RG / (0.2S _EM 0.75) (4) With

A _MG

required total number of e-mobiles

S _EC

required total energy storage of e-mobile [MWh]

S _EM

Energy storage per e-mobile [kWh]

The total number required for the assumptions made is 124,800 e-mobiles.

S₂₄

über den Tag benötigter Gesamtspeicher [MWh]

t₂₄

Ladezeit über einen Tag [h]

In addition, it should be ensured that at least 78 MW is charged around the clock in order to be able to represent the positive control power by reducing the charging power. S ₂₄ = L _SRP t ₂₄ (5) With

S ₂₄

total storage required over the day [MWh]

t ₂₄

Loading time over one day [h]

A_MG

benötigte Gesamtanzahl E-Mobile

S₂₄

über den Tag benötigter Gesamtspeicher [MWh]

E_B

Energieverbrauch im Betrieb pro E-Mobil [kWh/km]

L_TF

Tagesfahrleistung pro E-Mobil [km/Tag]

This means that at least 1,872 MWh of electrical energy should be loaded into the battery storage of electric vehicles in the grid area every day and this energy should also be "handled". This calculates the required number of e-mobiles as follows: A _MG = S ₂₄ / E _B / L _TF (6) With

A _MG

required total number of e-mobiles

S ₂₄

total storage required over the day [MWh]

E _B

Energy consumption in operation per electric vehicle [kWh / km]

L _TF

Daily mileage per e-mobile [km / day]

With an energy requirement of 0.18 kWh / km and an average daily mileage of each E mobile of 40 km results in a required total of 260,000 electric vehicles.

Taking into account a safety factor to cover fluctuations in the provision of control power in practice, this results in a total required number of 375,985 unidirectional electric vehicles. This corresponds to 34% of the private vehicle fleet of EWE's household customers.

On weekends where there is less traffic than on an average day, there may be bottlenecks in providing positive balancing power. If the low mileage persists for an extended period of time, the battery storage capacity reserves (defined above as 20% of the storage contents) are fully charged, so that bottlenecks in the provision of negative secondary control power can also occur.

Before longer distances and for the battery maintenance the battery of a E-Mobils should be completely fully loaded. An electric vehicle with a fully charged memory can not participate in the provision of secondary control power. Likewise, an e-mobile that is specifically prepared for an imminent trip and therefore fully loaded can not participate in the provision of control power. This fact does not affect the number of vehicles required because it reduces the available acceptance power, which however, as shown above, does not represent a bottleneck. The energy limitation is thereby rather not influenced.

With regard to the economy of the unidirectional variant according to the invention, the following should be noted:
In the case of the unidirectional variant according to the invention, there is no additional cyclization, ie forced discharge by means of feedback, the battery by means of V2G and thus no additional outlay arises during operation. As with the bidirectional variant, however, the revenue is generated from the performance price of the secondary control service offer as well as from the use of the favorable negative secondary control power (see above), although it is divided among more e-mobiles. The 135,470 MWh from negative secondary control power are divided into 375,985 e-mobiles, so that 360 kWh / year of free charging would be possible for each e-mobile. This results in a saving of approximately EUR 74 / E-Mobil and year, corresponding to approximately 14% of the total annual energy costs for the E-Mobil.

The unidirectional variant also has a clear economic advantage over the bidirectional variant, since a cost for a recovery of positive secondary control energy is avoided according to the invention.

So far, the provision of secondary control power has been considered. In particular, unidirectional V2G is also suitable to provide primary control power. With the unidirectional V2G, there are no additional costs due to the provision of positive or negative control energy. This is advantageous since the control energy provided or removed is not remunerated in the primary control. The price is determined solely by the service to be provided. Bidirectional V2G, on the other hand, is not suitable for providing primary control power because the energy costs of this variant could exceed the yields.

Even compared to the direct competitor in the market for control energy, the pumped storage power plant, the unidirectional V2G with its negligible cost and technically represents advantageous; the bidirectional V2G can not withstand the opposite.

• – Verkauf zusätzlicher elektrischer Energie für die Ladung von Batterien in Elektrofahrzeugen
• – Aktive Stützung schwacher Netzteile in kritischen Situationen
• – Abnahme von Spitzen aus der Einspeisung erneuerbarer Energien, bzw. Glättung von Lastgängen
• – Ggf. dezentraler Blindleistungsausgleich Ggf. dezentrale Oberschwingungskompensation
• – Entlastung der Übertragungsnetze aufgrund der dezentralen Verteilung der Speicher.

The vehicle to grid according to the invention has, among other things, the following advantageous effects from the perspective of the network operator:

• - Sale of additional electrical energy for charging batteries in electric vehicles
• - Active support of weak power supplies in critical situations
• - Reduction of peaks from the feed-in of renewable energies, or smoothing of load cycles
• - Possibly. decentralized reactive power compensation Ggf. decentralized harmonic compensation
• - Relief of transmission networks due to the decentralized distribution of memory.

The following is a consideration for the sale of electrical energy. Each household owns an average of 1.1 cars. These are replaced by e-mobiles that are charged from the electrical network. As mentioned above, a car drives an average of 40 km per day, ie. H. 14,600 km per year. Assuming the scenario presented above, an e-mobile consumes 0.18 kWh / km. This is 14,600 km × 0.18 kWh / km = 2,628 kWh per year. This is 75% of the average power consumption of a household without e-mobility of approximately 3,500 kWh / year.

As described above, much of the energy can be covered by negative secondary control energy. In addition, the use of the storage and the resulting possible time shift of the cargo can be used to provide energy that is offered at low prices on the market.

The unidirectional e-mobile according to the invention achieves active support of weak networks in critical situations.

For unidirectional V2G, the load in the EWE grid area could be reduced by 78 MW within seconds, if necessary. This is 9.6% of the average load in the EWE grid area of 812 MW.

In the following, an embodiment of a decrease of peaks from the feed-in of renewable energies or smoothing of the load path in the low-voltage grid is described. A combination of control power supply and load profile smoothing can be done as follows:
As shown above, the loading load of the unidirectional E-mobile variant could be kept constant by shifting the loading over time (see 2 ). This flexibility is due to the presence of the battery storage device according to the invention. This advantage can also be exploited to the effect that the predicted Ladelastgang is deliberately changed from the constant course in a curve. This curve could fill in the valleys of a projected household load or industrial stretch. As a result, in addition to the control power provision, the daily load of general electrical energy consumption can be smoothed, thus reducing the need for expensive peak load.

Alternatively, in this way a predicted fed-in power from wind farms or a combined load gear from z. B. Household load minus wind supply be smoothed. This procedure is in 3 shown graphically. This can be done on the following day economic optimization of electricity purchases for the e-mobile charge. If the reality deviates from the prognosis, then one of the presented control performance procedures comes to bear. The transmission system operators, for example, write wind reserve as a kind of control power. The development of this market could be further observed and included in the V2G concept.

3 shows a schematic representation of the V2G charging power and unidirectional provision of positive and negative secondary control performance as a function of a typical household load cycle with superimposed wind power curve (designations A, B, C, D as in 2 ).

The typical household load is initially superimposed with the wind power generated in the EWE grid area (this is only shown schematically and is not based on the exact data for wind power and household load in the EWE grid area). Depending on the resulting load profile, the V2G loading cycle is predicted. Its course corresponds to a reflection of the household load with wind power superimposition on a horizontal axis, whereby it can be smoothed from the point of view of the grid operator by the compensation of peaks and dips. In addition, the provision of positive and negative secondary control power is guaranteed at all times. As shown above, it must be possible to switch off up to 78 MW (positive secondary control power) at any time without endangering the safety band. This provides charging power for e-mobiles of up to 42 MW at any time of the day. In addition, an additional intake of up to 62.4 MW (negative secondary control power) must be possible at all times.

Due to the fluctuating course of the loading operation, there is a difference of> 78 MW between this and the safety band over most of the day. This results in a need for electric vehicles for this form of energy management, which exceeds the number calculated above. The additionally required charging power is designated at the location of its largest amplitude P _Z. P _Z depends on the number of additional e-mobiles.

Similar to the intraday trading on the stock exchange, performing commercial transactions within a day, P _Z can be offered over the course of the day the short term at good prices. This procedure makes it possible to integrate renewable energy into the electrical grid more intensively. According to the invention a relief of the transmission networks is achieved due to decentralized distribution.

In Germany, the main production areas of renewable energy in the form of wind turbines lie in the north on the coast, the main load areas in southern Germany. Pumped storage power plants, which could absorb surplus power from renewable energies, tend to be located in southern Germany due to geological conditions.

The implementation of unidirectional V2G in the grid area of EWE will make available a highly flexible storage facility for renewable energies in northern Germany. This relieves the transmission networks. In this way, the network operator, z. As EWE, make independent of the surrounding transmission system operators.

It can thus be stated that the unidirectional vehicle-to-grid according to the invention offers technical advantages over bidirectional conventional coupling. In the following, an embodiment will be described with which the unidirectional vehicle to grid according to the invention in the network area of a network operator, z. B. EWE, can be implemented efficiently and technically advantageous. In particular, a technical solution proposal for communication site implementation is provided.

In order to be able to carry out a regulation (and billing) of the battery charge of an e-mobile, the network operator receives the following information in its central office:
From the vehicle: IP address of the vehicle to allow the vehicle owner or driver to charge the fueled power. A nominal load cycle with tolerance bands that can be used for control power provision. Alternative: Battery storage capacity, minimum and maximum charge power, current battery maintenance requirements, current battery state of charge, scheduled time of next trip, and / or minimum amount of energy to charge (based on the power or power that needs to be transferred through the power plug).
from the house: Identification of the electricity customer, whose counter is used to obtain the electricity for the vehicle's charge, in order to charge it if the electricity customer does not own the vehicle to be charged; Identification via IP address if necessary.
from the smart meter (placement of the smart meter is not specified): the amount of energy consumed.
From the driver: The acceptance of the offered electricity price if this is flexible, to bring about a contract between the driver and the network operator.

• – Es sollen E-Mobile von beliebigen Nutzern an beliebigen Steckdosen geladen werden können.
• – Es sollen mehrere individuell abzurechnende Fahrzeuge an das Netz eines Stromkunden angeschlossen werden können, wie zum Beispiel in einem Parkhaus (→ Smart Meter entweder an der Steckdose oder im Fahrzeug).
• – Wenn das Abrechnungssystem, d. h. Kopplungssystem, (zunächst) nur im Netzgebiet der EWE installiert wird, soll ein Fahrzeug auch ungeregelt und ohne automatische Abrechnung außerhalb des EWE Gebietes geladen werden können.
• – Sollte das Abrechnungssystem von mehreren Netzbetreibern übernommen werden, so sollte eine automatische Abrechnung auch in einem „fremden” Netzgebiet stattfinden können. Die Verrechnung zwischen den Netzbetreibern sollte automatisch erfolgen, so dass der Fahrer nur eine Rechnung von einem Netzbetreiber erhält (ähnlich dem Roaming aus dem Mobilfunkbereich).
• – Das System funktioniert bevorzugt sowohl für E-Mobile im Besitz von EWE als Leasinggesellschaft als auch für E-Mobile im Besitz anderer natürlicher oder juristischer Personen.
• – Die Zuordnung von Automobilen zu Netzen von Stromkunden, an denen sie gerade geladen werden, muss eindeutig sein, selbst wenn zwei Steckdosen, die zu verschiedenen Stromkundennetzen gehören direkt nebeneinander hängen.
• – Sicherheits- und Datenschutzbestimmungen für den digitalen Zahlungsverkehr müssen eingehalten werden.

Further boundary conditions:

• - E-Mobile should be able to be loaded by any user at any power outlets.
• - Several individually billable vehicles can be connected to the grid of a power customer, such as in a parking garage (→ Smart Meter either at the socket or in the vehicle).
• - If the billing system, ie coupling system, (initially) only installed in the network area of EWE, a vehicle should also be able to be loaded unregulated and without automatic billing outside the EWE area.
• - If the billing system is taken over by several network operators, automatic billing should also be possible in a "foreign" network area. The billing between the network operators should be automatic, so that the driver receives only one bill from a network operator (similar to roaming from the mobile sector).
• - The system works preferably both for E-Mobile owned by EWE as a leasing company and for E-Mobile owned by other natural or legal persons.
• - The assignment of automobiles to networks of electricity customers, where they are currently loaded, must be unique, even if two sockets, which belong to different power customer networks hang directly next to each other.
• - Security and privacy policies for digital payments must be respected.

The following constellation is a suggestion to implement the above requirements:
Each E-car in the network area of EWE, whose owner wants to buy his electrical energy for battery charging at EWE, receives a calibrated and sealed "EWE-E-Mobil-Box", which is installed in his vehicle. It performs the following functions: It measures the electrical charging power and calculates the charged energy for billing with the network operator, communicates with the on-board electronics and collects the information required by the vehicle and the driver via the CAN bus of the vehicle. About an RFID tag, which is glued to the socket, the e-mobile box receives the assignment of the socket to a household / household meter. The RFID tag should be designed to self-destruct in an attempt to forcibly remove it from the power outlet (similar to a car sign). In addition, the RFID tag can carry the inscription "charging station". The information of the driver is determined according to the method described below.

As soon as all the required information is available, the EWE E-Mobile Box sends it via Power-Line Communication to the central gateway in the low-voltage network section, which communicates with the DEMS and, if necessary, returns a command to release the load at a specific electricity tariff. The electricity tariff depends on the clearances granted by the driver for the time shift by the network operator.

The network operator returns a desired current charging power for the electric vehicle to be charged via the central gateway to the charging station, which gives the electric vehicle the command to obtain this charging power. The E-Mobile implements this command.

By identifying the socket as a "charging station", which belongs to a specific household meter, double billing by offsetting can be avoided.

In addition to simple outlets marked by RFID tags, there are public outlets that provide power only when an e-mobile has successfully identified itself. In this way, Stromklau is avoided with other consumers.

Such a process is in 4 shown schematically: 4 shows a schematic representation of the network coupling of electric vehicles. The e-mobile 50 be via the EWE e-mobile box 83 and a conventional single or three-phase plug to a conventional power outlet 80 of a household 70 or a public outlet 81 z. B. in a parking garage 71 connected. This becomes one by sticking on an RFID tag, which defines the affiliation to a household Charging station. When docking, the socket identifies itself to the E-Mobile box, which is connected to the central gateway 14 communicated through Powerline Communication. The central gateway is available anyway for smart metering in the relevant network section and does not have to be specially installed for the V2G. The E-Mobile Box transmits the user and vehicle data as well as the IP of the socket from the CAN bus 84 to the central gateway. This forwards the information by means of a TCP / IP communication 85 to the DEMS, which returns the release to the charge via the central gateway to the E-Mobile Box. The charge can thus be assigned to a specific e-mobile. After reading the household meter 82 the energy consumed for the E-Mobil charge can be offset against the household meter reading. A double billing is thus avoided. Public sockets will only be given a release to charge when an E-Mobile is connected to prevent misuse.

The communication between the network and the driver, taking flexible electricity tariffs into account, takes place as follows:
The purchase price of the electricity is z. B. due to success or failure in the standard power tender but also other market mechanisms vary. The network operator can pass on the risk of energy trading to the end customer and offer a flexible electricity price. On the one hand, this may encourage the e-vehicle user to participate more intensively in the V2G and to allow the network operator more flexibility in the use of the battery storage in the vehicle. On the other hand, a flexible electricity price limits the financial planning security of the vehicle owner / driver. A compromise could be that the driver is guaranteed that the flexible electricity price is always below the fixed household tariff.

The determination of possible load profiles and the electricity price can take place in three phases:

Step 1: Data input by the driver: The driver indicates to the communication unit when he would like to arrive at which location after the next trip. The navigation device of the vehicle calculates the route and returns the departure time. The driver should be provided with speed dial options, such. For example: "Drive to work tomorrow at the usual time".

Step 2: Calculation of possible load cycles by the battery management system: The E-mobile box / communication unit determines from the entered data and the battery data (battery charge state, battery aging state, battery charge characteristics) the curve of the power demand over time with accepted tolerance bands and transmits these to the network operator.

Step 3: Calculation of the electricity tariff for the load: On the basis of the power requirement and its tolerance bands as well as on the basis of the already available control band sold to the transmission system operator, the network operator automatically calculates the current electricity tariff.

Step 4: Confirmation of the electricity tariff or change of the boundary conditions: If the driver agrees with the offered price, he confirms this and the battery charge can begin. If he does not agree, he can change the boundary conditions, repeat step 1 and start the cycle again.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The 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

• DE 69220228 T2 [0009, 0009, 0010]

Cited non-patent literature

• VDE 0126 [0006]
• VDE 0126 [0006]
• VDE 0126 [0007]
• VDE 0126 [0067]

Claims (12)

Charging control system for controlling a unidirectional charging of an electric vehicle, with a power grid for providing electrical energy, an electric vehicle for connection to the power grid, wherein the electric vehicle has a battery unit for charging by storing electrical energy and a charging control unit for controlling the charging of the battery unit, and a computer unit for determining a consumption power in a network section of the energy network, for predicting a charge load cycle for the vehicle on the basis of the determined consumption power and for sending the predicted charge load cycle to the charge control unit, wherein the charge control unit is configured to receive the predicted charge cycle and to control the charging of the battery pack according to the predicted unidirectional charge cycle. Charging control system according to claim 1, wherein the charge control system further comprises a further electric vehicle with a further battery unit and a further charge control unit, wherein the computer unit is configured for predicting a combined charge load cycle for the electric vehicle and the further vehicle on the basis of the determined consumption power and for sending the predicted combined charge load passage to the charge control unit and the further charge control unit, wherein the charge control unit is configured to receive the predicted combined charge cycle and to control the charging of the battery pack according to the predicted combined charge cycle, and wherein the further charging control unit is configured to receive the predicted combined charge operation and to control the charging of the further battery unit according to the predicted combined charge operation. Charge control system according to claim 1 or 2, wherein the consumption power represents the usage behavior of the vehicle and / or the other vehicle. Charge control system according to one of the preceding claims, wherein the computing unit is configured to output a positive control signal to the charging control unit to provide positive power to the network section, and wherein the charge control unit is configured to throttle the charge power of charging the battery pack according to the predicted charge duty according to the positive control signal. Charge control system according to claim 4, wherein the positive control signal has a time information representing a time or a period, and wherein the charge control unit is configured to throttle the charge power of charging the battery pack according to the predicted charge duty according to the positive control signal during the time or the period. Charge control system according to one of the preceding claims, wherein the predicted cargo load has minimum information representing a minimum cargo load to provide positive control power to the network portion, and wherein the charge control unit is configured to control the charging performance of charging the battery pack between the predicted charge cycle and the minimum charge cycle. Charge control system according to one of the preceding claims, wherein the computing unit is configured to output a negative control signal to the charging control unit to provide the network section with negative control power, and wherein the charge control unit is configured to increase the charging power of charging the battery unit according to the predicted charge duty in accordance with the negative control signal. Charging control system according to claim 7, wherein the negative control signal has a time information representing a time or a period, and wherein the charge control unit is configured to increase the charge power of charging the battery pack according to the predicted charge duty in accordance with the negative control signal during the time or the period. Charge control system according to one of the preceding claims, wherein the predicted charging load has maximum information representing a maximum charging load for providing negative control power to the grid section, and wherein the charge control unit is configured to control the charging performance of charging the battery pack between the predicted charge cycle and the maximum charge cycle. A charging control system according to any one of the preceding claims, wherein the predicted charge cycle is a reflection of the determined consumption power to smooth a load peak in the grid section. Charge control system according to one of the preceding claims, wherein the charging control unit is designed to perform the charging of the battery unit with at least a safety charging performance. A method for controlling a unidirectional charging of an electric vehicle, comprising the steps Providing electrical energy in a power grid, Determining a consumption power in a network section of the power grid, Predicting a charging load for the electric vehicle based on the determined consumption power, Connecting the electric vehicle to the power grid, wherein the electric vehicle has a battery unit for charging by storing electrical energy, and Controlling the charging of the battery unit of the electric vehicle according to the predicted unidirectional Ladelastgang.

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