Method and apparatus for energy management for an electric vehicle charging system

A method and an apparatus for energy management including an input for a first sensor, which is designed to detect a first measurement variable as information about a current to a home energy management system. A device is designed to determine a second measurement variable depending on the first measurement variable. An output designed to output the second measurement variable, instead of the first measurement variable, as information about a current to the home energy management system for the home energy management system.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to German Patent Application No. 10 2019 106341.8, filed Mar. 13, 2019, the content of such application being incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The invention relates to a method and an apparatus for energy management.

BACKGROUND OF THE INVENTION

JP 2012050236 and US2018159326, each of which is incorporated by reference in its entirety, disclose home energy management systems that are suitable for charging electric vehicles by means of an electric vehicle charging system. For overall smooth energy management, these systems must be compatible with one another. It is therefore desirable to provide a possibility of integrating an electric vehicle charging system into an already existing home energy management system.

SUMMARY OF THE INVENTION

A method for energy management makes provision for a first measurement variable to be detected at a first sensor as information about a current to a home energy management system, wherein a second measurement variable is determined depending on the first measurement variable, wherein, instead of the first measurement variable, the second measurement variable is output as information about a current to the home energy management system for the home energy management system. Therefore, an alternative measurement value can be prescribed in order to prevent undesired effects occurring in the home energy management system when an electric vehicle charging system is connected.

Provision is preferably made for the second measurement variable to be output as information about the current to the home energy management system in an analog or digital manner for measurement by a second sensor for the home energy management system. The alternative measurement value is thus able to be output simply to a home energy management system, which uses a sensor for current measurement.

Provision is preferably made for the second measurement variable to be output as a sensor signal in an analog or digital manner to the home energy management system. The alternative measurement value is thus able to be output simply to a home energy management system without an additional sensor for current measurement having to be used.

The first measurement variable is preferably determined at a connection point of the home energy management system to an energy supplier network. The alternative measurement value is measured at the same location at which home energy management systems usually also provide the measurement.

A current at the connection point of the home energy management system to the energy supplier network is preferably determined as first measurement variable. This simplifies the determination of the alternative measurement values.

The second measurement variable is preferably a current or an electromagnetic field that simulates a current. Said analog signals can be coupled in directly by means of a current sensor of the home energy management system.

An electromagnetic signal is preferably produced for a measurement by the second sensor. As a result, no real power has to be applied when the second measurement variable is output.

An apparatus for energy management comprises a first sensor, which is designed to detect a first measurement variable as information about a current to a home energy management system, a device, which is designed to determine a second measurement variable depending on the first measurement variable, and an output, which is designed to output, instead of the first measurement variable, the second measurement variable as information about a current to the home energy management system. This makes it possible to simply integrate an electric vehicle charging system into a home energy management system without elements of the home energy management system having to be changed.

Provision is preferably made for the output to be designed to output the second measurement variable as information about the current to the home energy management system in an analog or digital manner for measurement by a second sensor for the home energy management system. This makes it possible to connect the apparatus for energy management directly to a sensor for current measurement that is already installed in the home energy management system.

The output is preferably designed to output the second measurement variable as a sensor signal in an analog or digital manner to the home energy management system. This makes it possible to connect the apparatus for energy management directly to home energy management system that is already installed.

The first sensor is preferably designed to determine the first measurement variable at a connection point of the home energy management system to an energy supplier network. Using the first the measurement variable, information about the energy provided by the energy supplier network is determined at the location to which the home energy management system and the electric vehicle charging system are connected.

The first sensor is preferably designed to determine a current at the connection point of the home energy management system to the energy supplier network as first measurement variable. For home energy management systems with a current sensor, this simplifies the determination of the alternative measurement values.

The output is preferably designed to output as second measurement variable a current or an electromagnetic field that simulates a current. This simplifies the installation of the apparatus without having to make changes to the home energy management system.

The output preferably comprises a coil, which is designed to produce an electromagnetic signal for a measurement by the second sensor. The application of a real power can therefore be prevented.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows a schematic illustration of parts of a home energy management system100. The home energy management system100comprises a home storage system102, a photovoltaic device104, one or more consumers106, an inverter108, which connects the photovoltaic device104to a home electricity grid110, to which the consumer or consumers106and the home storage system102are connected.

An electric vehicle charging system112for an electric vehicle114and an apparatus for energy management116are connected to the home electricity grid110.

The apparatus116comprises an input118for a first sensor120, which is designed to detect a first measurement variable122as information about a current to the home energy management system100. The apparatus116comprises a device124, which is designed to determine a second measurement variable126depending on the first measurement variable122. More specifically, the first measurement variable122is changed to the second measurement variable126at least during operation of the electric vehicle charging system112.

The apparatus116comprises an output128. In the example, the output128is designed to output the second measurement variable126for measurement by a second sensor130for the home energy management system100. In the example, the output128is designed to output the second measurement variable126as information about the current to the home energy management system100in an analog manner for measurement by the second sensor130for the home energy management system100. For a second sensor130that makes it possible, the information can also be output in a digital manner.

As an alternative, the output128can be designed to output the second measurement variable126as a sensor signal in an analog or digital manner to the home energy management system100. In this case, the second sensor130can be omitted. Instead, in this case, the output128is connected to a signal line132between the sensor130and the home storage system102.

The device124can be embodied as an analog switching technology. The device124preferably comprises an analog-to-digital converter118A at the input118and a digital-to-analog converter128A at the output128as well as a microprocessor124A, which is designed to determine the second measurement variable126depending on the first measurement variable122. The microprocessor124A is preferably designed to change the first measurement variable122to the second measurement variable126for example during operation of the electric vehicle charging system112. The microprocessor124A makes it possible to store and process the functionality that makes it possible to change the measurement variables within the context of the compatibility of the systems. Instead of the microprocessor124A, a processor and a separate storage system, which enable the functionality, can also be provided.

Independently of the embodiment of the device124, the device124provides the possibility of adapting a conventional electric vehicle charging system112and a home energy management system100to one another without the electric vehicle charging system112or the home energy management system100themselves having to be adapted. In the event that the electric vehicle charging system112is already adapted for an existing home energy management system100, the device124can be designed as an interface for the charging system112such that the home energy management system100itself does not have to be adapted.

In the example, the first sensor120is designed to determine the first measurement variable122at a connection point134of the home energy management system100to an energy supplier network136. In the example, the first sensor120is designed to determine a current at the connection point134of the home energy management system100to the energy supplier network136as first measurement variable122.

In the example, the output128is designed to output as the second measurement variable126a current that simulates a current. In the example, the simulated current flows across the second sensor130via a connecting line138. An arbitrary current profile different from the actual current profile at the connection point134can thus be prescribed to the second sensor130. In the example, actuation signals for the electric vehicle charging system112are transmitted from the apparatus116to the electric vehicle charging system112via an actuation line140. Said actuation line can likewise be a current signal of a current sensor otherwise connected to the electric vehicle charging system112. When the electric vehicle charging system112makes it possible, a separate actuation can also be transmitted instead of or in addition to information about a current. The sensors may comprise a coil, which is wound around a cable in which the current that is to be measured flows. The sensors may be designed as current clamps.

As an alternative thereto, the output128may be designed, as illustrated inFIG. 3, to output as the second measurement variable126an electromagnetic field that simulates a current. In this case, the output128comprises a coil302, which is designed to produce an electromagnetic signal for a measurement by the second sensor130.

Instead of the described current measurement and current change, another variable relevant for the control of the home energy management system100can also be detected and changed. For example, a control variable relevant to charging and discharging the home storage system102is detected and changed.

A method for energy management is described in the following text with reference toFIG. 2.

In a step202, the first measurement variable122is detected at the first sensor120as information about the current to the home energy management system100. In the example, the first measurement variable122is determined at the connection point134of the home energy management system100to the energy supplier network136. The current is determined at the connection point134of the home energy management system100to the energy supplier network136as first measurement variable122. Other measurement points, for example in the home electricity grid, are also possible.

A step204is then executed.

In step204, the first measurement variable122is changed to a second measurement variable126. In the example, the change is determined based on information present due to the current measurement at the connection point134. Alternative measurement values for the output as second measurement variable126are determined so that the home energy management system100and the electric vehicle charging system112provided for charging electric vehicles together result in smooth energy management. Provision may be made for information about the first measurement variable122, in particular the measured current, to additionally be transmitted to the electric vehicle charging system112. In addition or as an alternative thereto, provision may be made for the electric vehicle charging system112to be actuated directly.

A step206is then executed.

In step206, the second measurement variable126for the home energy management system100is output. In the example, the second measurement variable126is output as information about the current to the home energy management system100in an analog manner for measurement by the second sensor130for the home energy management system. Instead, the second measurement variable126can also be output as a sensor signal in an analog or digital manner to the home energy management system100. In the example, the second measurement variable126is a current. However, the second measurement variable126can also be output as an electromagnetic field that simulates a current. In this case, the electromagnetic signal is produced for the measurement by the second sensor130.

FIG. 3illustrates a schematic illustration of a part of the home energy management system100in which a coil302is provided at the output128. The coil302is designed to produce an electromagnetic signal for a measurement by the second sensor130. In this example, the second sensor130comprises a coil for measuring the electromagnetic signal. This enables an installation in which no real power is transmitted between the coil302and the second sensor130.