DE102019132027A1 - Portable plug-in power supply unit for the temporary connection of an electrically drivable motor vehicle with a stationary power network and operating procedures for the plug-in power supply unit - Google Patents

Abstract

The invention relates to a portable plug-in power supply unit (10) for temporarily connecting an electrically drivable motor vehicle (27) to a power supply system (28), the plug-in power supply unit (10) having a vehicle connection (11) and a power supply connection (12) and in the plug-in power supply unit (10 ) a converter circuit (22) is set up to convert between a line voltage of a power system (28) and a battery voltage of a motor vehicle (27). The invention provides that a control circuit (21) is set up in the plug-in power supply unit (10) to reduce an electrical power (P) transmitted by the converter circuit (22) between the vehicle connection (11) and the network connection (12) to an adjustable reference value (R) to regulate and / or limit and to set the reference value by means of an assignment rule (Z) as a function of a respective temperature signal (20) of at least one temperature sensor (18), the assignment rule (Z) setting the reference value (R) in such a way that the transmitted electrical power (P) is greater than zero and less than a maximum maximum power that can be transmitted by the converter circuit (22).

Description

The invention relates to a portable power plug charger, which can be designed, for example, as a charging cable for temporarily connecting an electrically drivable motor vehicle to a stationary power supply system. The invention also relates to a method for controlling the transmission of electrical power in the plug-in power supply.

In order to enable the so-called traction battery, i.e. the electrochemical accumulator, to be recharged in an electrically powered motor vehicle, provision can be made to provide a plug-in power supply that can be temporarily connected to the motor vehicle in order to connect its battery to the stationary power supply. The plug-in power supply is designed to be portable, that is, it can be withdrawn or disconnected from the motor vehicle as well as from the power supply and, for example, carried in the trunk of the motor vehicle. A plug-in power supply has the electrical converter circuit necessary for the charging operation, that is to say the power electronics for controlling the electrical power flow for the charging operation, so that the motor vehicle itself does not have to be designed with a corresponding charger.

In order to increase the flexibility when recharging the battery of a motor vehicle, the so-called AC charging functionality is desired, which enables the motor vehicle to be recharged on an AC power grid, such as the conventional public power grid with, for example, 230 volts alternating voltage or 120 volts alternating voltage to be able to. Since such a plug-in power supply also enables recharging at a connection socket of a household power network, protection must be guaranteed in order to be able to safely carry out a charging operation on an outdated household installation. If, for example, the power grid has an insufficiently large line cross-section to be able to transfer the maximum charging power of the converter circuit of the plug-in power supply and the battery of the motor vehicle, the electrical lines in the building's power grid can heat up.

From the DE 10 2009 002 429 A1 It is known that a plug-in power supply unit designed as a charging cable can perform an automatic shutdown when a temperature sensor signals a temperature value above a threshold value. This then interrupts the charging process, which is carried out via this charging cable. However, at the end of the charging time, a fully charged, electrically drivable motor vehicle is no longer available.

How a temperature can be measured in a mains connection of a plug-in power supply, i.e. the plug for plugging into the socket, is, for example, in the DE 10 2015 206 840 A1 described. An emergency shutdown is also recommended here if the temperature is above a threshold value. It is described that after the emergency shutdown one has to wait for a while and then the charging operation can be resumed. However, this intermittent or intermittent charging requires more charging time than desired.

From the DE 10 2013 016 550 A1 it is known that the temperature of an electrical contact pin can be measured by means of a resistance element with NTC (Negative Temperature Coefficient) or PTC (Positive Temperature Coefficient) via galvanic separation. As a result, the temperature of an electrical contact element can be measured in a mains connection, that is to say a plug for plugging into a socket, without the mains voltage that is applied to the contact element also being transmitted. Control options for a charging process based on this are not described.

The invention is based on the object of designing a portable plug-in power supply, such as it can be configured as a charging cable, for example, in such a way that it can be operated reliably on power networks with different power transmission capacities.

The object is achieved by the subjects of the independent claims. Advantageous embodiments of the invention are described by the dependent claims, the following description and the figures.

The invention describes a portable plug-in power supply unit by means of which an electrically drivable motor vehicle can be temporarily (for example for each individual charging process) connected to a stationary power supply system. In the manner described, the plug-in power supply can be designed as a charging cable. The charging cable or, in general, the plug-in power supply unit is designed to be portable, that is to say it is not permanently connected to the motor vehicle or to the power supply system. Rather, the plug-in power supply has an electrical vehicle connection for plugging into an electrical connection socket of the motor vehicle and an electrical network connection for insertion into a connection socket of the power supply system. The power grid represents a stationary infrastructure; it can be, for example, a public power grid or the power grid of a household installation. The two connections (vehicle connection and mains connection) can be used, for example, as plugs in a manner known per se be designed. The vehicle connection can, for example, be designed in accordance with the IEC 62196 standard and, for example, be designed for one or more or all of the charging modes 1, 2, 3, 4. The mains connection can be designed, for example, as a household plug (so-called protective contact plug, Schuko plug) or as a multi-phase so-called three-phase plug. A converter circuit is already integrated or provided in the plug-in power supply, which converter circuit is set up to convert between a line voltage of the power system and a battery voltage of the motor vehicle. In other words, the motor vehicle itself no longer needs its own charger. In the power grid, too, the power grid voltage can be provided directly at the power grid connection socket; no converter is required on the side of the power grid. Rather, all of the power electronics required to control or adjust the power flow for charging the energy store of the drivable motor vehicle (that is, its battery) can be provided by the converter circuit of the plug-in power supply itself. On the vehicle side, the converter circuit can therefore provide for the output of a direct voltage or a DC voltage (DC direct current). On the network side, the converter circuit can be designed for the transmission of an alternating voltage or an AC voltage (AC alternating current) and / or a direct voltage or DC voltage.

In order to be able to operate such a plug-in power supply flexibly on power networks with different transmission capacities with regard to the electrical power, according to the invention a control circuit is provided in the plug-in power supply which is set up to reduce the electrical power transmitted by the converter circuit between the vehicle connection and the network connection to an adjustable reference value to regulate and / or limit. The reference value can therefore serve as a setpoint value for regulation and / or as an upper limit value for clipping or power limitation. However, this reference value is not fixed, but rather configured to be adjustable, that is to say it can be changed dynamically during operation. For this purpose, it is provided that the control circuit is set up to set the reference value by means of an assignment rule as a function of a respective temperature signal of at least one temperature sensor. At least one temperature sensor is therefore provided which supplies a temperature signal. The signal values of the respective temperature signal can be mapped as a whole to the reference value by means of the assignment rule. Several temperature signals can be combined, for example, by weighted summation. The assignment rule can be designed as a look-up table and / or as a characteristic value and / or as a mathematical calculation rule. The control circuit can accordingly have at least one microcontroller and / or at least one microprocessor for operating the assignment rule. The assignment rule is designed in such a way that the assignment rule provides a reference value that provides for a transfer of electrical power that is greater than 0 (i.e. not switched off), but is less than a maximum power that can be transferred by the converter circuit. In other words, the assignment rule provides for a throttling of the transmitted power as a function of the respective temperature signal of the at least one temperature sensor. If a temperature sensor indicates a rising temperature by means of the temperature signal, the assignment rule accordingly results in a falling reference value, so that when the temperature rises, as indicated by a temperature signal, the reference value becomes lower or smaller, so that less electrical power through the converter circuit is transmitted. This results in less heat loss and thus the measuring location at which the temperature signal is generated by a temperature sensor can cool down again. However, this does not result in an interruption of the transmitted electrical power, rather the charging process for the motor vehicle can continue to be operated or carried out.

The invention has the advantage that the electrical power transmitted by the plug-in power supply is regulated as a function of the temperature signal of the at least one temperature sensor. A regulation to a setpoint value (for example a PID regulation; PID - Proportional Integral Differential) or a clipping to a maximum value can be provided here. This is described here combined as setting a reference value for regulation and / or limitation. Overall, the derating described results, that is to say, the reduction in the charging power, as a function of a temperature measurement that indicates a rising temperature. The reference value can be set in several stages, in particular more than three stages, for which purpose the assignment rule can be designed accordingly. This avoids having to interrupt the charging process. The temperature sensor used in each case can take place in the manner already described on the basis of a PTC and / or NTC element.

In the plug-in power supply, there is thus overall independent control and / or regulation through the integration of power electronics that provide temperature-controlled derating. It can therefore be used universally, as all the components required for charging are carried along in the plug-in power supply itself, including protection against overheating of an external line of a power grid.

The invention also encompasses embodiments which result in additional advantages.

In one embodiment, at least one of the at least one mentioned or said temperature sensor is arranged or integrated in the network connection. This at least one temperature sensor is designed to measure a contact temperature of at least one electrical contact or contact element (pin), which transmits said line voltage of the power system. In other words, the contact temperature of this electrical contact element can be measured with the at least one sensor and a temperature signal corresponding to or correlated with the contact temperature can be provided. An infrastructure-side temperature measurement on the electrical contact element is thus made possible. The at least one temperature sensor is integrated directly into the mains connection, for example an AC plug. The at least one temperature sensor can thus be used to determine line heating in the power supply system indirectly via the electrical contact element. This makes it possible to identify or record when there is a temperature increase in the power grid. In this way, the power transmission through the plug-in power supply can be controlled as a function of a temperature in the power grid, as can be determined or estimated indirectly via the contact temperature. This enables the power grid to be protected from overloading or overheating.

For this purpose, one embodiment provides for the control circuit and the converter circuit and the vehicle connection to be arranged in a common housing which has a handle for user manipulation. Such a housing can, for example, be the vehicle connection already described in accordance with the IEC 62196 standard. The mains connection for connecting to the power supply is connected to this housing via a flexible cable and the at least one temperature sensor, which is integrated in the mains connection, is electrically connected to the control circuit via a respective measuring line which is integrated in the cable. Thus, the temperature measurement in the network connection is realized via its own measuring circuit based on the measurement line, this circuit being independent of the circuit by means of which the electrical power is transmitted between the power network and the motor vehicle. This can therefore be an independent low-voltage measuring circuit with the measuring line from the plug or mains connection to the control circuit. An alternative transmission of the respective temperature signal of the at least one sensor instead of or in addition to a measuring line can take place by means of a power line communication (PLC) and / or by means of a radio link. Such a radio link can be implemented on the basis of Bluetooth, for example. The at least one temperature sensor and the measuring line are preferably galvanically separated in the manner described from the line voltage of the power system and the battery voltage of the motor vehicle. The measuring line can be connected, for example, to an analog-to-digital converter (ADC) of a processor device of the control circuit. Such a processor device can be implemented in the manner described on the basis of at least one microprocessor and / or at least one microcontroller.

In one embodiment, at least one of said at least one temperature sensor is arranged in the vehicle connection on an electrical contact element which carries or transmits the battery voltage. This also protects the vehicle electrical system from overheating.

Additionally or alternatively, at least one temperature sensor can be arranged in the converter circuit in order to also provide temperature protection for the plug-in power supply unit itself.

In one embodiment, the control circuit of the plug-in power supply is set up to determine a time gradient of the respective temperature signal, i.e. a change in the time profile of the respective temperature signal, and to set the reference value, via which the power transmission in the converter circuit is controlled, by means of a predetermined regulator criterion that the gradient of the at least one temperature signal deviates from the value 0 by less than a predetermined tolerance value. In other words, by means of the regulator criterion by controlling or setting the reference value, the aim is to achieve a constant temperature profile (temperature change, that is to say gradient of the temperature signal equal to 0 or different from 0 by less than the tolerance value). The tolerance value can range from 1 ° C per hour to 1 ° C per 10 minutes. The controller criterion can be based, for example, on a PID controller algorithm or a PI controller algorithm. In this way, a steady operating point for the temperature at the at least one temperature sensor is aimed for. This enables continuous operation for the plug-in power supply.

In one embodiment, the control circuit is set up to increase the contact temperature signaled by the respective temperature signal to a respective maximum permissible To regulate the contact temperature value of the respective contact. The respective contact element on which the respective temperature signal is determined or recorded is therefore operated at its maximum permissible temperature value, so that the maximum possible electrical power is transmitted. This also results in a maximum temperature gradient from the vehicle connection or network connection to the respective network (on-board network or power network). However, this also forces a temperature flow or energy flow away from the plug-in power supply, so that the lines into the on-board network or into the power network can also be used as heat sinks. There is therefore a flow of heat into the motor vehicle and / or into the house installation.

In one embodiment, said converter circuit is an AC / DC converter circuit which provides a line-side AC line voltage into a vehicle-side DC battery voltage. Additionally or alternatively, the converter circuit can provide a DC / DC conversion of a network-side DC network voltage into a vehicle-side DC battery voltage. With the DC / DC conversion, for example, a photovoltaic system can also be used to charge the battery of the motor vehicle. With the AC / DC conversion, a public alternating current network can be used to charge the motor vehicle. The network connection can be configured to be single-phase or multi-phase in order to be able to transmit a corresponding multiple of electrical power that can be transmitted per phase.

In one embodiment, an equalizer and / or a primary side of the converter circuit assigned to the network connection is coupled to at least one contact element of the vehicle connection via a thermal path which is galvanically separated from the battery voltage and the network voltage and has a thermally conductive metal. A contact element is a current-carrying metallic contact that carries the battery voltage and is electrically connected to the vehicle's electrical system when the vehicle connector is plugged in. As a result, waste heat from the converter circuit, namely the rectifier stage, which is particularly prone to heat generation during traveling operation, and / or the primary side, can be dissipated into at least electrical power of an electrical system of the motor vehicle. The metal for conducting the waste heat can be provided by a choice of the circuit board structure by means of a so-called thick-film circuit board and / or a circuit board with an additional, non-current-carrying cooling plate. The galvanic decoupling can be provided by means of an electrically insulating material in the thermal path. The thermal path can therefore be recognized by the fact that there is a metallic connection (apart from the material of the galvanic decoupling) between the converter circuit and the at least one contact element (pin) of the vehicle connection that is not intended for a charging current. The material of the galvanic decoupling is overall preferably thinner than 1 centimeter in the thermal path.

In one embodiment, the converter circuit is designed for bidirectional operation. Thus, by means of the plug-in power supply unit, not only a charging function (power transfer from the power grid to the motor vehicle), but also a feedback (power transfer from the motor vehicle to the power grid) can be implemented. Thus, by means of the motor vehicle, electrical energy can also be fed into the power grid, which, for example, can be remunerated for the user of the motor vehicle. In particular in combination with a converter circuit that provides both AC / DC conversion and DC / DC conversion, a user can charge the vehicle's battery on his photovoltaic system, for example, and then use the AC to charge electrical energy from the vehicle's battery / DC conversion from the battery to an AC alternating voltage of a public power grid or feed back.

In one embodiment, the control circuit has at least one processor device and a communication device and is configured to use the processor device and the communication unit to determine from the motor vehicle a respective value of a charging current currently required by a vehicle battery and / or a currently required charging voltage. The processor device can be the described arrangement of at least one microcontroller and / or at least one microprocessor. The communication unit can, for example, provide wired and / or optical and / or radio-based communication with a control device of the motor vehicle. By receiving the respective value for the charging current and / or the charging voltage, the charging process can also be adapted to the current state of charge of the vehicle battery by the control circuit. The control circuit is set up accordingly to control the converter circuit for setting the respective current value (for charging current and / or charging voltage). The converter circuit is set up to set the respective current value by means of pulse width modulation (PWM). Thus, when controlling the transmitted electrical power, the current state of the vehicle battery can also be taken into account, so that the vehicle battery is electrically, in particular, directly connected to the connection socket of the motor vehicle without an intermediate converter stage, in which the vehicle connection of the plug-in power supply is plugged galvanically, can be connected. This is a particularly simple and therefore inexpensive solution in terms of circuitry.

The converter circuit and / or the vehicle connection and / or the network connection can each additionally provide at least one fuse element for blocking an electrical current in the event of a current strength above a threshold value (overcurrent), in particular in the event of a short circuit. Protection is thus also provided in the plug-in power supply against a circuit fault.

The control circuit can provide that, in the event that the temperature signal cannot be kept below a predetermined threshold value by means of the assignment rule described, the transmission of the electrical power is interrupted, that is to say the charging current is set to 0.

The operation of the plug-in power supply according to the invention results in a method which is also part of the invention. During a charging process, according to the method, a converter circuit is operated in the plug-in power supply, which converts between a line voltage of the power system and a battery voltage of the motor vehicle. Depending on the mode of operation (charging operation or feedback), the electrical power is transferred from the power grid to the motor vehicle (charging mode) or from the motor vehicle from its vehicle battery to the power grid (feedback).

In this case, a control circuit in the plug-in power supply regulates an electrical power transmitted by the converter circuit between the vehicle connection and the network connection to a reference value, which in turn can be changed or adjusted over time. Additionally or alternatively, the power can be limited to the reference value, in which case the value of the power can then be adjusted to a target value smaller than the reference value according to another criterion, for example the state of charge of the vehicle battery. The control circuit sets said reference value by means of a predetermined assignment rule as a function of a respective temperature signal of at least one temperature sensor. The assignment rule here sets a reference value which is a transmitted power greater than 0 and less than a maximum maximum power that can be transmitted by the converter circuit. In other words, the assignment rule maintains the charging process, even if the temperature signal signals a changing, in particular a rising, temperature. If the temperature rises, the reference value is lowered by the assignment rule, so that the temperature rise is counteracted and the gradient of the temperature signal is set to 0 or less than 0.

The invention also comprises embodiments of the method according to the invention which have features as they have already been described in connection with the embodiments of the plug-in power supply unit according to the invention. For this reason, the corresponding developments of the method according to the invention are not described again here.

The plug-in power supply can, for example, be provided in a portable or removable manner in a motor vehicle. Such a motor vehicle can in particular be a motor vehicle, for example a passenger car or truck.

• 1 eine schematische Darstellung einer Ausführungsform des erfindungsgemäßen Steckernetzteils;
• 2 eine schematische Darstellung einer weiteren Ausführungsform des erfindungsgemäßen Steckernetzteils;
• 3 eine schematische Darstellung einer Ausführungsform des erfindungsgemäßen Steckernetzteils mit einer Skizze zur Veranschaulichung der Leitungsbelegung;
• 4 eine schematische Darstellung einer Wandlerschaltung und einer Steuerschaltung, wie sie in dem erfindungsgemäßen Steckernetzteil bereitgestellt sein kann; und
• 5 eine weitere schematische Darstellung der Wandlerschaltung und der Steuerschaltung.

Exemplary embodiments of the invention are described below. This shows:

• 1 a schematic representation of an embodiment of the plug-in power supply according to the invention;
• 2 a schematic representation of a further embodiment of the plug-in power supply according to the invention;
• 3rd a schematic representation of an embodiment of the plug-in power supply according to the invention with a sketch to illustrate the line assignment;
• 4th a schematic representation of a converter circuit and a control circuit, as it can be provided in the plug-in power supply according to the invention; and
• 5 a further schematic representation of the converter circuit and the control circuit.

The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention which are to be considered independently of one another and which also further develop the invention in each case independently of one another. Therefore, the disclosure is also intended to include combinations of the features of the embodiments other than those illustrated. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

In the figures, the same reference symbols denote functionally identical elements.

1 shows a plug-in power supply 10 , which can be designed as a charging cable for an electrically driven motor vehicle. The plug-in power supply 10 can connect to a vehicle 11 to plug into a connection socket (not shown) of an electric motor vehicle and a mains connection 12th for plugging into a connection socket (not shown) of a power supply system. A network connection is shown here 12th , which is designed as a so-called Schuko plug for a single-phase connection socket of a power network.

The vehicle connection 11 can be used as part of a housing 13th be designed, which also has a handle 14th may have, by means of which a user can have the housing 13th hold and the vehicle connection 11 of the housing 13th can insert or plug into said socket of the motor vehicle. The grid connection 12th can use a flexible cable 15th with the case 13th be connected. The cable 15th can be more than one meter in length.

2 illustrates an embodiment of a plug-in power supply 10 that are different from the plug-in power supply 10 of 1 allows a multi-phase transmission of a line voltage of a power grid. The mains connection 12th be designed as a multi-phase plug, in particular as a so-called three-phase connection. The rest already related to 1 The elements described can also be used with the plug-in power supply 10 of 2 be provided. For this reason, the description of the 1 referenced.

3rd again illustrates a plug-in power supply 10 with the mains connection 12th and the cable 15th . Below the illustration of the plug-in power supply 10 is once again from the cable 15th shown as individual electrical lines 16 can be provided. In the network connection 12th can have several electrical contact elements 17th be provided, which can be designed, for example, as metal parts. In 3rd is the respective electrical assignment L1 , N, PE specified as it is known per se for plug-in power supplies. In addition, for one or more of the contact elements 17th in the network connection 12th , in particular in a housing of the same, each with a temperature sensor 18th be provided, by means of which a respective current temperature of the contact element 17th to which the respective temperature sensor 18th is assigned, can be measured. Any temperature sensor 18th can use one of the lines 16 that act as a test lead 19th can be designed, in each case a temperature signal 20th to a control circuit 21 transmit the respective temperature signal 20th can receive and depending on the respective temperature signal 20th power electronics with a converter circuit 22nd can control which one via at least one of the remaining electrical lines 16 transferred electrical power P in relation to the voltage and / or the current and convert to contact elements 17 ' of the vehicle connection 11 can provide. At least one temperature signal 20th can in this case be mapped to a reference value R by means of an assignment rule Z, which is used as a setpoint value for power regulation and / or as a limit value for power limitation when the converter circuit is in operation 22nd can be used.

A pin assignment of the contact elements 17 ' is in 3rd with the usual designations DC +, DC-, CP - Control Pilot, PP - Proximity Pilot, which are known from the prior art, the communication lines that are galvanically separated from the transmission of the converted electrical power are also specified here. The AC / DC converter integrated in the connector converts the AC voltage between L1, N into a DC voltage for charging via DC +, DC-.

4th once again illustrates a possible arrangement of the control circuit 21 and the power electronics of the converter circuit 21 in the housing 13th of the plug-in power supply 10 . The control circuit 21 can at least one processor device 23 have, which can include, for example, a microcontroller. Furthermore, at least one analog-to-digital converter 24 be provided, for example, the respective temperature signal 20th from the measuring line 19th to be able to convert it into a digital signal. In addition to the converter circuit 22nd can an EMC filter 25th be provided, for example, a pulse width modulation that is generated by the converter circuit 22nd can be carried out without any reaction to the grid connection 12th to be able to perform. The converter circuit 22nd can be designed for an AC / DC conversion, for which a circuit known per se from the prior art can be provided.

5 once again illustrates a possible configuration of the plug-in power supply in a more detailed representation 10 with the vehicle connection 11 and the power supply 12th that via the converter circuit 22nd can be coupled. The control circuit 21 can by means of their processor device 23 and a communication unit 26th a communication signal 26 ' exchange with the motor vehicle (not shown) in order to thereby obtain a by means of the converter circuit 22nd transferred electrical power also to a current state of charge of a vehicle battery B of the motor vehicle 27 to be able to customize.

In 5 is also the power grid 28 represented by an element to which the network connection 12th via a connection socket 29 can be connected. The vehicle connection 11 can be connected to a connection socket 30th of the motor vehicle 27 connected or plugged in.

In addition, at least one securing element 31 in the plug-in power supply 10 be provided in the event of a fault current by means of switching elements 32 to completely interrupt a current flow. A security element 31 can, for example, be a fuse 33 Provide an electronic fuse as an additional fuse element 34 include.

Overall, an electrical power P, the amount of which can be passed through the converter circuit 22nd can be controlled between the vehicle connection 11 and the power supply 12th be transmitted. In the motor vehicle 27 In this case, a battery voltage Ub can be made available which corresponds to a battery voltage of a vehicle battery of the motor vehicle; a network voltage Un, for example an alternating voltage, can be provided in the power network. The battery voltage Ub can be, for example, a high-voltage voltage, that is to say a direct voltage greater than 60 volts.

• Der im Stecker integrierten Leistungselektronik/ Ladeelektronik wird direkt die infrastrukturseitige AC-Spannung (L1, L2, L3, N und PE) zugeführt. Je nach Ausbaustufe kann das Steckernetzteil einphasig (L1, N und PE) oder mehrphasig ausgeführt sein. Der integrierte Mikrocontroller µC (allgemein die Prozessoreinrichtung 23) übernimmt die Kommunikation zum Fahrzeug und überwacht, steuert und regelt die Leistungselektronik. Zusätzlich sind am Eingang- sowie Ausgang bevorzugt Sicherungselemente integriert, um das Netzteil bzw. das Fahrzeug vor Überstrom und Kurzschluss zu schützen. Das Steckernetzteil (Power Plug Charger) ist bevorzugt in folgenden Leistungsstufen umgesetzt: einphasige Versorgung (L1, N, PE) 3,6kW Ladeleistung; zweiphasige Versorgung (L1, L2, N, PE) 7.2kW Ladeleistung; dreiphasige Versorgung (L1, L2, L3, N, PE) 11 kW Ladeleistung.

The integration of the charging and power electronics can be implemented as an example as shown in the figures:

• The infrastructure-side AC voltage (L1, L2, L3, N and PE) is fed directly to the power electronics / charging electronics integrated in the connector. Depending on the expansion stage, the plug-in power supply can be single-phase (L1, N and PE) or multi-phase. The integrated microcontroller µC (generally the processor device 23 ) takes over the communication to the vehicle and monitors, controls and regulates the power electronics. In addition, fuse elements are preferably integrated at the input and output in order to protect the power supply unit or the vehicle from overcurrent and short circuits. The power plug charger is preferably implemented in the following performance levels: single-phase supply (L1, N, PE) 3.6kW charging power; two-phase supply (L1, L2, N, PE) 7.2kW charging power; three-phase supply (L1, L2, L3, N, PE) 11 kW charging power.

1. 1. Veraltete Hausinstallation z.B. in Altbauten. Verbau von Leitungsquerschnitten die nicht mehr dem Stand der Technik erfüllen. Zusätzlich wurden Verteilungen nicht abgesichert, so sind durch viele parallele Verbraucher Überlastungen möglich.
2. 2. Leitungsquerschnitt der Hausinstallation nicht für einen Dauerbetrieb mit maximaler Leistung ausgelegt. Ladevorgang mit 3.6kW und einem BEV erfordert mehrere Stunden Dauerleistung der Hausinstallation.
3. 3. Klemmstellen-Steckdose/ Verteilungen innerhalb der Hausinstallation. Jede Klemmstelle innerhalb der Hausinstallation kann zu erhöhten Kontaktwiderstanden uns somit zur Erwärmung führen.
4. 4. Verschmutzung der Kontakte am AC-Stecker. Eine Verunreinigung der AC seitigen Ladestecker führt ebenfalls zu einem erhöhten Kontaktwiderstand und somit zu einer Erwärmung der Kontakte. Herkömmliche Haushaltssteckdosen (Schuko-Steckdosen) bzw. die Leitungen in der Hausinstallation, die zu einer Schuko-Steckdose führen, sind normalerweise nicht für hohe Dauerströme ausgelegt, weshalb man eine Schuko-Steckdose nicht mit mehr als 8 bis 10 Ampere dauerhaft belasten sollte. Die Kontakte und Leitungen können sonst überhitzen, was bestenfalls zu einer schnelleren Alterung der Kontakte führt, im schlimmsten Fall aber sogar zum Brand. Die maximale Strombelastbarkeit hängt dabei auch stark vom Baujahr der Elektroinstallation sowie der Leitungslängen im Gebäude ab.

Especially when charging in a private environment, the following factors can overload the infrastructure-side periphery. An overload inevitably leads to an undefined and uncontrolled warming / heating. In the worst-case scenario, this can lead to a cable fire, a smoldering fire in the socket or house installation. Possible causes can be:

1. 1. Outdated house installation, for example in old buildings. Installation of line cross-sections that no longer meet the state of the art. In addition, distributions were not secured, so overloading is possible due to many parallel consumers.
2. 2. The line cross-section of the building installation is not designed for continuous operation with maximum output. Charging with 3.6kW and a BEV requires several hours of continuous power from the house installation.
3. 3. Terminal point socket / distributions within the building installation. Every terminal point within the house installation can lead to increased contact resistance and thus to heating.
4. 4. Contamination of the contacts on the AC plug. A contamination of the AC side charging plugs also leads to an increased contact resistance and thus to a heating of the contacts. Conventional household sockets (Schuko sockets) or the lines in the house installation that lead to a Schuko socket are usually not designed for high continuous currents, which is why you should not permanently load a Schuko socket with more than 8 to 10 amps. Otherwise, the contacts and lines can overheat, which at best leads to faster aging of the contacts, but in the worst case even to a fire. The maximum current capacity also depends heavily on the year of construction of the electrical installation and the cable lengths in the building.

Due to the fact that the OBC (onboard charger) is no longer in the vehicle itself and the power electronics / charging electronics are integrated directly into the charging plug of the plug-in power supply unit, it should be the task of the charger to monitor the temperature of the infrastructure-side AC connection plugs. The temperature of the AC plug contacts is recorded e.g. via thermocouples (PTC, NTC, etc.) directly in the AC plug (i.e. on the side of the power grid) and is preferably fed to the plug-in power supply via separate lines in the charging cable and evaluated and monitored by the µC. If the contacts at the interface between the charging cable and the AC socket heat up, this heat build-up is recorded and a derating (reduction of the charging power) is initiated. If this does not result in a steady-state operating point, the plug-in power supply switches off the charging process. In addition, the detection of the temperature enables an additional functionality to regulate the charging power via a temperature dependency. Thus, the availability for the customer is significantly increased at the same time.

• - Sicherstellung eines sicheren Zustands des Steckernetzteils (Power Plug Chargers),
• - Vermeidung von Überlastung der Hausinstallation o Vermeidung von Kabel-Steckdosenbränden,
• - Erhöhung Ladeverfügbarkeit für Fahrzeugnutzer,
• - selbst bei nicht optimaler Hausinstallation kann über die Derating-Funktion mit eingeschränkter Leistung weitergeladen werden,
• - Steigerung der Robustheit des gesamten Ladesystems.

This has several advantages:

• - Ensuring a safe state of the plug-in power supply unit (Power Plug Charger),
• - Avoidance of overloading the building installation o Avoidance of cable socket fires,
• - Increase in charging availability for vehicle users,
• - Even if the house installation is not optimal, the derating function can continue to charge with limited power,
• - Increasing the robustness of the entire charging system.

The temperature sensors are integrated directly into the AC plug, making it possible to measure the contact temperature of the Schuko plug. The temperatures of the terminal point or the line heating are also recorded. The measuring lines of the temperature sensors are run parallel to the AC lines in the cable and fed to the plug-in power supply. The temperature detection is carried out galvanically separated from the AC voltage.

The sensor lines are fed in past the power electronics part (the converter circuit), for example through the connector handle into the LV part of the control electronics. There the individual sensors are read in and evaluated in the µC via ADC (Analog Digital Converter) channels. Depending on the recorded temperature, the µC regulates the charging power or switches off the charging process. The derating function also runs on the µC, the regulation takes place by controlling the power semiconductors via PWM.

The idea thus describes a hardware and function of temperature measurement, temperature evaluation and the control / regulation of a DC charging process. The idea is preferably implemented in a charging cable that integrates the power electronics in the so-called DC combo connector. (Energy conversion from AC to DC as well as from DC back to AC) The vehicle is charged exclusively via DC direct voltage. An onboard charger in the vehicle is no longer necessary, i.e. there is no additional converter stage in the vehicle itself. In order to integrate the charging power electronics, they should be able to dissipate the power loss that occurs during charging. The temperature measurement of the AC and DC contacts is used for cooling the integrated power electronics via the plug contacts. In order to achieve the maximum charging power, the power electronics are controlled in such a way that the maximum permissible contact temperature of the AC and DC contacts is reached. This creates a heat flow in the direction of the AC supply line (house installation) and in the direction of the DC line (vehicle). In addition, my invention disclosure offers the option of a bidirectional charging function. The plug-in power supply can convert energy from the vehicle into an alternating voltage and feed it back into the grid. Here, too, precise measurement of the temperature of the AC and DC contacts is necessary.

1. 1. Temperaturmessung AC- sowie DC-Kontakte. Grundlage für die Entwärmung der integrierten Leistungselektronik über die Steckkontakte Richtung Kabelzuleitungen. Regelung das maximale Steckkontakttemperatur eingestellt wird, dadurch Entwärmung über Kabelbaum möglich.
2. 2. Keine Beschränkung auf AC-Laden (Wechselstromnetz)- DC Ladefunktionalität auch möglich.
3. 3. Kein Beschränkung auf LV-Ladeelektronik -Integration der Leistungselektronik und Energiewandlung im Steckernetzteil.
4. 4. Integration einer Derating-Ladefunktion direkt in den Ladestecker. Präzise Ladeleistungseinschränkung bei Übertemperatur.
5. 5. Bidirektionale Ladefunktionalität implementierbar.
6. 6. Keine Beschränkung auf klassische Fahrzeugarchitektur mit Onboard Ladegerät.

In summary, the following aspects arise:

1. 1. Temperature measurement AC and DC contacts. Basis for cooling the integrated power electronics via the plug contacts in the direction of the cable feed lines. Control the maximum plug contact temperature is set, thus cooling via the wiring harness is possible.
2. 2. No restriction to AC charging (alternating current network) - DC charging functionality is also possible.
3. 3. No restriction to LV charging electronics - integration of power electronics and energy conversion in the plug-in power supply.
4. 4. Integration of a derating charging function directly into the charging plug. Precise charging power limitation in the event of excess temperature.
5. 5. Bidirectional charging functionality can be implemented.
6. 6. No restriction to classic vehicle architecture with onboard charger.

Overall, the examples show how the invention can provide an active temperature sensor for overheating protection of a socket in a plug-in power supply of an electrically drivable motor vehicle.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was 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.

Patent literature cited

• DE 102009002429 A1 [0004]
• DE 102015206840 A1 [0005]
• DE 102013016550 A1 [0006]

Claims (10)

Portable plug-in power supply unit (10) for temporarily connecting an electrically drivable motor vehicle (27) to a stationary power supply system (28), the plug-in power supply unit (10) having an electrical vehicle connection (11) for plugging into an electrical connection socket (30) of the motor vehicle (27) and has an electrical network connection (12) for plugging into a connection socket (29) of the electricity network (28) and a converter circuit (22) is provided in the plug-in power supply unit (10) which is set up to switch between a network voltage (Un) of the electricity network (28) ) and to convert a battery voltage (Ub) of the motor vehicle (27), characterized in that a control circuit (21) is provided in the plug-in power supply unit (10) which is set up to connect one of the converter circuit (22) between the vehicle connection (11 ) and to regulate and / or limit the electrical power (P) transferred to an adjustable reference value (R) and the reference value rt (R) can be set by means of an assignment rule (Z) as a function of a respective temperature signal (20) of at least one temperature sensor (18), the assignment rule (Z) setting the reference value (R) in such a way that the transmitted electrical power (P) is greater is less than zero and less than a maximum maximum power that can be transmitted by the converter circuit (22). Plug-in power supply (10) Claim 1 , wherein at least one temperature sensor (18) of the at least one temperature sensor (18) is arranged in the mains connection (12) for measuring a contact temperature on an electrical contact element (17) which transmits the mains voltage (Un). Plug-in power supply (10) Claim 2 , wherein the control circuit (21) and the converter circuit (22) and the vehicle connection (11) are arranged in a housing (13) which has a handle (14) for user handling, and the mains connection (12) via a flexible cable ( 15) is connected to the housing (13) and the at least one temperature sensor (18) of the mains connection (12) via a respective measuring line (19) which is integrated into the cable (15) and / or via a powerline communication and / or is connected to the control circuit (21) via a radio link. Plug-in power supply (10) according to one of the preceding claims, wherein at least one temperature sensor of the at least one temperature sensor (18) is arranged in the vehicle connection (11) on an electrical contact element (17 ') which transmits the battery voltage (Ub). Plug-in power supply (10) according to one of the preceding claims, wherein the control circuit (21) is set up to determine a time gradient of the respective temperature signal (20) and to set the reference value (R) by means of a predetermined control criterion in such a way that the gradient from zero to deviates less than a predetermined tolerance value. Plug-in power supply (10) according to one of the preceding claims, wherein the control circuit (21) is set up to regulate the temperature signaled by the respective temperature signal (20) to a respective predetermined maximum permissible temperature value. Plug-in power supply (10) according to one of the preceding claims, wherein the converter circuit (22) is an AC / DC conversion of a mains-side AC mains voltage into a vehicle-side DC battery voltage and / or a DC / DC conversion of a mains-side DC mains voltage into the vehicle DC battery voltage. Plug-in power supply (10) according to one of the preceding claims, wherein a rectifier stage and / or a primary side of the converter circuit (22) assigned to the mains connection via a thermal path, which is a thermally conductive metal, is galvanically separated from the battery voltage (Ub) and the mains voltage (Un) having, is coupled to at least one contact element (17 ') of the vehicle connection (11). The plug-in power supply unit (10) according to any one of the preceding claims, wherein the control circuit (21) has at least one processor device (23) and a communication unit (26) and is set up to use the processor device (23) and the communication unit (26) from the motor vehicle ( 27) to determine a respective value (26 ') of a charging current currently required by a vehicle battery (B) and / or a currently required charging voltage and to control the converter circuit (22) to set the respective current value, and the converter circuit (22) for this purpose is set up to set the respective current value by means of pulse width modulation, PWM. Method for operating a plug-in power supply (10) according to one of the preceding claims, wherein in the plug-in power supply (10) a converter circuit (22) converts between a line voltage (Un) of the power supply system (28) and a battery voltage (Ub) of the motor vehicle (27), characterized in that in the plug-in power supply unit (12) a control circuit (21) transfers electrical power (P) from the converter circuit (22) between a vehicle connection (11) of the plug-in power supply unit (10) and a mains connection (12) of the plug-in power supply unit (10) regulates and / or limits to an adjustable reference value (R) and the Setting the reference value (R) by means of a predetermined assignment rule (Z) as a function of a respective temperature signal (20) of at least one temperature sensor (18), the assignment rule (Z) setting the reference value (R) in such a way that the transmitted power (P) is greater as zero and less than a maximum power that can be transmitted by the converter circuit (22).

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