DE102014013870B4 - Mobile testing system for automotive charging stations - Google Patents

Abstract

Mobile testing system of a car charging station comprising a vehicle with a built-in measuring device for testing the car charging station, characterized in that the testing system has a simulation of a communication error between the car charging station and the vehicle, wherein the reaction of the car charging station to the error makes it possible to determine whether predetermined processes, in particular a power interruption, are triggered thereby.

Description

The present invention relates to a mobile testing device for an automotive charging station, in particular a charging station with preferably a charging mode 2 to 4 according to DIN EN 61851-1, preferably for at least one CCS charging station. Furthermore, a testing method is proposed that can also utilize the mobile testing device.

Car charging stations are necessary if we want to achieve increased use of electric vehicles on the road. These car charging stations can be designed differently depending on the connector type used, charging voltage, and other considerations.

US 7 688 024 B2 describes a charging control system for an electric vehicle.

DE 10 2010 014 081 A1 describes an additional electrical energy storage device for a motor vehicle.

WO 2012 / 106 372 A2 describes a fast charging plug for charging an electric vehicle.

US 2011 / 0 202 217 A1 describes a method and a device for connecting an electric vehicle to a power grid.

The object of the present invention is to ensure the safety of a car charging station.

This object is achieved with a mobile testing system having the features of claim 1 and a method having the features of claim 10. Advantageous embodiments and further developments emerge from the following description as well as from the subclaims.

A mobile testing system for an automotive charging station is proposed, which comprises a vehicle with a built-in measuring device for testing the automotive charging station.

A car charging station is a charging facility for electric vehicles. This can be publicly or privately accessible. The vehicle, in particular a battery pack of the vehicle, is connected to the car charging station. Preferably, a battery of an electrically powered vehicle is connected and charged via a cable connection. The mobile test system preferably uses a conductive charging system for electric vehicles, as specified in DIN EN61851-1.

There are a wide variety of automotive charging systems. In the simplest case, for example, a 230 V, 16 A socket to which the battery can be connected. Automotive charging systems with three-phase connections are also known. In addition to charging a single battery or vehicle, it can be provided that several battery sets or vehicles can be charged simultaneously and/or one vehicle can be charged at an accelerated rate. Known systems of testable automotive charging systems include CHAdeMO, which originated in Japan, the Tesla Supercharger system from the USA, and the CCS charging system in Europe. This list is exemplary but not exhaustive. In an automotive charging system, in particular a charging station, different charging systems can be integrated alongside one another. According to one embodiment, the proposed mobile testing system is capable of testing various charging systems. For this purpose, the mobile testing system can, for example, have several battery sets. This allows, for example, each charging system to be tested with one battery set of the vehicle, either at least partially simultaneously and/or at least partially sequentially. In particular, the mobile testing system is capable of monitoring and evaluating the entire charging process.

Preferably, a charging system is tested that complies with the EN 62196 Type 2 standard in Europe, also known as Mennekes IEC Type 2. This is a universal plug system for electric cars with a charging power range of preferably 1.9 kW to 240 kW. The mobile test system is preferably used to test the charging standard favored in the country of manufacture of the vehicle in question. This means that the mobile test system, depending on its design, is capable of testing the multitude of adapters and various charging control boxes used to charge a vehicle. The test system is capable, for example, of testing plugs and cables that are constructed in accordance with the usual standards for electrical devices, such as IEC 60309/CEE.

According to one embodiment, the mobile testing system comprises a vehicle with a battery pack, by means of which testing of the automotive charging station is carried out. It is preferred if the vehicle is an electric vehicle, the battery pack of which is used for testing. The vehicle can also be a hybrid vehicle or have a range extender. According to a further embodiment, the vehicle has an energy dissipation device, such as a discharger. The energy dissipation device can be used to to provide for targeted discharge of the accumulator, preferably to a predefined state.

Preferably, the battery pack is brought to a defined charge level. This enables, for example, repeatability of tests or even testing of electrical charging. Furthermore, the electrical energy absorbed during the test can be used to travel from one charging station to the next. It is also possible to enable defined initial states for conducting the test, adapted to different automotive charging systems or battery systems. This makes it possible, for example, to conduct multiple tests on the same automotive charging system, each with different battery pack charge levels at the start of each test.

A further development provides for the vehicle to have several separable battery sets, with a first battery set being available for testing separately from a second battery set. This makes it possible, for example, to ensure that an empty battery is always available.

Furthermore, the mobile testing system can also be used for battery swapping. This refers to charging stations where batteries are not charged with electricity, but rather swapped for pre-charged batteries. This eliminates the need for time-consuming charging, and with a sufficiently dense network of stations, unlimited journeys are possible.

A further embodiment of the mobile test system provides for the test system to have several, in particular different, simulations that, for example, test the charging operation of the automotive charging station. This can include a functional test of areas or parts, but also a safety test of parts or areas of the vehicle and the automotive charging station. The mobile test system can therefore preferably test various areas or provide support in doing so. In addition to design requirements for an automotive charging station, such as immobilizer and mechanical protection, other points must be tested, for example, electrical protection, residual current protection, overload protection, and/or component protection. For example, the mobile test system can test the following: previously untested load conditions, simulated cable breaks, simulation of insulation faults (asymmetric and symmetric), functional variances, such as different loads, charging periods, current strengths, as well as feedback effects on a power supply network, simulation of poor plug contacts due to corrosion, and/or simulation of various communication errors, etc. The power supply network can be a public or private supply network. It can also be a self-sufficient grid, such as an island solution. In this case, the mobile testing system can be used to test the impact of renewable energy generators, intermediate storage, and other factors, for example, through load simulations.

A further embodiment provides, for example, that the mobile testing system additionally has a device with which a vehicle can be simulated, for example for the purpose of testing according to DIN VDE 0100-600 or DIN VDE 0105-100 . Depending on the application, this additional option allows, for example, a comparative test to be carried out with the vehicle's battery as well as with the vehicle simulator.

It is preferred if the mobile testing system includes at least one simulation of a communication error between the car charging station and the vehicle. The car charging station's reaction to the error can be used to determine, for example, whether predefined processes are triggered, such as a power outage.

A further development provides for the mobile testing system to check the car charging station and the vehicle. For example, faster charging is the aim for today's batteries. The required power can be provided, but the respective vehicles must be equipped with the appropriate chargers. For example, the mobile testing system can simulate different vehicles, for example by using differently implemented chargers. The mobile testing system can, for example, store the identifier assigned to each electric vehicle and then simulate the corresponding vehicle at the respective car charging station to be tested. For example, electric vehicles with 12 to 20 kWh energy storage can be simulated, which have, for example, a three-phase connection with 16 A (11 kW) or 32 A (22 kW).

Higher-capacity plug-in systems can provide corresponding high-current chargers. Therefore, according to one design, the mobile test system is capable of simulating different systems that may not even be available on the market yet.

A further development of the testing system allows, for example, a fast-charging system to be tested by using an existing direct current grid. DC grids can be supply lines, for example, for trams in urban areas. This grid typically has a direct voltage in the range of 1 kV. Numerous substations supply the individual track sections separately, allowing public fast-charging stations to be set up using the existing grid and rectifier infrastructure and tested using the mobile testing system.

Furthermore, it can be provided that the mobile testing system takes into account a network effect of the car charging station on the electrical network to which the car charging station is connected.

The EN 62196 Type 2 charging standard, for example, enables a bidirectional communication channel between the vehicle and the car charging station at the CP pin of the connector. Using the CP signal, the car charging station, in particular the charging column, can read the charging power supported by the electric vehicle from the vehicle. If several car charging stations, in particular charging columns, share a single power connection at a charging station location, a central charging station load management system can, for example, use pulse width modulation via the CP pin to reduce the charging power of the chargers installed in the vehicles with the different modes, for example, modes 1-3, in such a way that the total charging power of all vehicles connected to the charging station does not exceed the maximum power connection power of the charging station facility. The charging time can therefore vary if several vehicles share a charging station facility. According to one design, the test system is capable of testing such influences. For example, it can be provided that a simulation of several vehicles is carried out in order to test their behavior. The testing system can also access multiple battery sets, which are preferably transported to the respective charging station in a mobile manner, for example, by the vehicle. These can be located in the vehicle itself and/or in a trailer. These can be used to test multiple charging of the charging station.

A further embodiment envisages considering the vehicle battery as part of the power grid of the car charging station. It can be charged when there is a surplus of energy in the grid (energy sink), and when there is a shortage of energy in the grid, energy can be fed back into the grid from the battery (“vehicle to grid”). This variant is implemented as DC charging mode (Mode 4). For example, this also assumes more DE 10 2011 013 453 A1 The mobile testing system is capable of recording and evaluating the relevant parameters and allowing appropriate conclusions to be drawn during the test.

Furthermore, a further embodiment provides that the mobile testing system is capable of testing different plug systems and different car charging stations.

• - Anschließen des aufzuladenden Akkumulatorsatzes an die Automobil-Ladestation,
• - Durchführen von mehreren Tests betreffend die Automobil-Ladestation beinhaltend zumindest das Zusammenwirken mit dem aufzuladenden Akkumulatorsatz, und
• - Entladen des zu Prüfzwecken aufgeladenen Akkumulatorsatzes vorzugsweise durch Betrieb des Fahrzeugs.

According to a further aspect of the invention, a method for testing a car charging station with a vehicle is proposed, which has at least one battery pack for driving, comprising the following steps:

• - Connecting the battery pack to be charged to the car charging station,
• - Carrying out several tests concerning the car charging station including at least the interaction with the battery pack to be charged, and
• - Discharge the battery pack charged for testing purposes, preferably by operating the vehicle.

Furthermore, one or more of the configurations described above and below can be implemented in the testing method. In particular, the mobile testing system is used to carry out the method.

A further development of the procedure provides for the use of a mobile testing system with a monitoring device that is capable of
to monitor the communication between a car charging station and a vehicle,
to recognize information sent in the communication,
with measured values of current, voltage and time for plausibility, whereby
Preferably, a comparison is made with the current state of the vehicle or the connection, in particular the current connection between the vehicle and the car charging station, for plausibility.

Particularly with DC charging, it is possible to determine by comparison whether the charging is actually taking place as desired, for example, according to predefined charging curves. In the event of a deviation, it can be checked whether this is still within a tolerance or already outside it. If the latter is the case, a corresponding error message can be generated. The monitoring device is preferably capable of testing how the fault behaves under different boundary conditions using one or more simulations. This allows, for example, the source of the fault to be narrowed down to the vehicle charging station, a cable, and/or a connector.

Furthermore, in addition to conductive charging, i.e., energy transfer via cables and connectors, the energy for charging the battery can also be transferred inductively. The charging system for General Motors' EV1, for example, was designed this way. Various considerations are also being made for using inductive systems, for example in the bus sector. Examples include a similar system from Conductix-Wampfler in Austria for electric buses and from Dassault in France. One design of the mobile testing system allows it to be used to test not only conductive but also inductive automotive charging stations.

Furthermore, the mobile testing system can be used not only at charging stations but also in private households, particularly to prevent malfunctions or overloads that could, in the worst case, trigger fires. Standard packages for charging electric cars in prefabricated garages are little known. Smaller electric vehicles such as electric bicycles, electric motorcycles, and small electric cars have a small battery capacity and can be charged using simple devices such as a standard 230 V, 16 A household socket. Charging an electric car with a larger battery capacity in a private household, for example, in a garage, places different demands on the charging infrastructure. This can also be tested using the mobile testing system, for example, to determine whether the existing network is even suitable for this purpose and what modifications are necessary. For example, standard household sockets are only suitable for continuous operation at rated load for several hours and are also not very mechanically resilient. Industrial sockets such as CEE Euro plugs, on the other hand, have increased mechanical resilience and are protected against water ingress. The mobile testing system is particularly capable of testing the 22 kW (400 V 32 A) three-phase power connection and the C red industrial socket recommended for charging electric cars in private garages. Even stronger and faster charging is possible with a suitable charger, for example, at 63 A. In the Renault ZOE, the traction battery can be charged to 80% in 30 minutes. These dimensions can be planned for when connecting to the home and then verified using the mobile testing system. Wall-mounted charging stations offered by electric car manufacturers and third-party manufacturers that provide a charging connection can also be tested.

Whether and how rapid charging affects the service life of batteries depends on the battery type used, the battery size, and the charging current. Lithium-ion batteries are described as capable of rapid charging. This means charging with charging rates >1C, which results in charging times of less than one hour. For modern battery systems, manufacturers usually specify a normal charge of 0.5C to 1C, whereby, for example, a 100 Ah cell can be charged with currents of 50-100 A. Such a battery can therefore be charged normally in around 2 hours without any loss of service life, provided the power connection and charger provide the necessary power. To ensure this, the mobile testing system can be designed to take into account the interaction of, for example, the battery, charging current, and charging voltage, also with regard to the service life.

A further development of the mobile test system provides for the possibility of distinguishing between slow, gentle and gentle charging compared to fast charging and, in particular, the differences between different batteries such as lead batteries, nickel-cadmium batteries, lithium iron phosphate batteries or lithium-ion batteries are taken into account in the respective simulation.

Furthermore, the mobile testing system is capable of testing separate fuses as well as one or more separate residual current devices (RCDs) used in the vehicle charging station. Such devices can be used, for example, as combination circuit breakers.

Furthermore, according to a further development, the mobile testing system can also test additional functions that may be provided in a car charging station or an electric vehicle, for example in the area of data transmission and data verification. For example, an identification number for operators of charging stations intended for public use in Germany can be used to enable the establishment of a roaming system. Furthermore, a test of the electric charging station identification (EVSEID) can also be carried out. Electric charging station operators require a unique ID for their electric charging station for cross-border billing, similar to the mobile phone roaming system. This is done using charging point identification (EVSEID). Equipment ID). The EVSEID consists of the country code (DE), the EVSE operator ID (3 digits), the ID type (E), and the power outlet ID (up to 30 digits). Simulation can be used to check whether this function is working properly and whether there has been any manipulation or error.

Since electric charging stations are currently barely or not at all listed on standard road maps or navigation systems, and the scope of services at electric charging stations is constantly changing, the mobile testing system can also be used to collect, process, and share related data, for example, in publicly accessible overview lists or similar formats. This also allows for the reporting of disruptions, for example.

A preferred embodiment of the mobile testing system provides an electric vehicle that is at least CCS-capable and provides a base load due to the existing and used battery. For example, the vehicle has the option of providing an external resistive load. This enables testing with higher power. An industrial control system, for example a PLC, is preferably installed. This can be used to control a communications center for monitoring and manipulating communication between a charging station and the electric vehicle. Furthermore, it is possible to use this system to carry out all switching operations in the testing device and to perform necessary evaluations. A measuring system is provided, which primarily enables the measurement of electrical parameters, but which also makes it possible to demonstrate the necessary electrical safety. A data analysis system is also provided, which enables evaluation and documentation, for example. Furthermore, a remote data transmission system is preferably provided in order to transmit recorded or evaluated data to a central storage device.

For example, functionalities such as those defined by IEC 62196 can be tested using the proposed mobile test system. The following list is only exemplary and not exhaustive: Control Pilot (pilot contact) measurement with frequency measurement and measurement of different voltage levels (State A, State B, State C, State D, -12V), a simulation of various vehicles / charging scenarios as well as a normal charge, a charging interruption for battery cooling, a delay in authentication (e.g. waking up the vehicle is necessary), a vehicle-side timer is used with delayed charging by the vehicle, a vehicle-side pre-conditioning is simulated, a vehicle error - start in State C (without State B), a simulation of various cable types, PP (Proximity Pilot, Proximity Switch) adjustable 13A, 20A, 32A, 0R and line open, checking whether Control Pilot is set according to PP, checking whether overcurrent is correctly detected and charging is stopped, control of resistive load, power levels 1-phase 2kW / 3.7kW / 7.3kW, power levels 3-phase 9kW / 15kW, temperature monitoring, AC/DC connection for charging the vehicle battery, testing of the automatic charging start, a network measurement and logging, for example, network currents (Ph 1, 2, 3), voltages (Ph 1, 2, 3), an energy measurement, a line break (cable/connector break), a PE break during charging, an interruption of communication lines such as CP and PP, disconnection of power connections, residual current device test (type A, B), residual current device tripping time test, tripping current, earth resistance test, network impedance test, analysis of an amplitude of a superimposed PLC signal, disconnection of the HV contacts, measurement of voltage overshoot during load shedding, insulation test, test circuit for generating a leakage current from HV to PE, analysis of the triggering delay/sensitivity of the charging station, voltage accuracy, checking the pre-charge behavior (deviation from the target spectrum), analysis of the charging station measurement deviation in different load cases, current accuracy, communication to the vehicle with BMS to query the permitted Charging current, charging current measurement and comparison with the vehicle's charging requirements, and/or analysis of the measurement deviation at the charging station under different load conditions. One or more of these tests are preferably integrated into the mobile test system and tested as part of the test procedure.

• 1 eine mögliche prinzipielle Ausgestaltung des mobilen Prüfsystems und
• 2 eine schematische Ansicht einer Verknüpfung von Kommunikationsstruktur und Leistungsstruktur mit dem Prüfsystem.

Further advantageous features and embodiments are apparent from the following figure. However, the details presented therein are to be understood only as examples and not as limiting. One or more features from the figure can also be combined with one or more features from the above description to form further embodiments. It shows:

• 1 a possible basic design of the mobile testing system and
• 2 a schematic view of a link between communication structure and performance structure with the testing system.

1 shows a schematic view of a test device in an electric vehicle with a test device controller. A central unit evaluates a Controlpilot signal and simulates various vehicle states and cable types. A step-adjustable resistive load is used as the load, and In other cases, the power can be transferred to the vehicle via a mobile fast charger. Power quality measurements are performed using accredited, stand-alone test equipment. This allows for checking, for example, adequate grounding, grid impedance, and insulation testing. The measurement connection provides a calibration option through comparative measurements.

2 shows a concept based on standard CCS, PLC, and CP vehicle communication. The test device taps into both the communication line and the power connections. The communication lines are merely evaluated and not modified. High-level communication takes place exclusively between the charging station and the vehicle. With the high-voltage connections (HV+, HV-), in addition to measuring current and voltage, it is also possible to simulate grounding faults and load shedding. During the analysis in the event of load shedding, the amount of excess voltage that can be measured on the DC bus is checked. Grounding faults are simulated by connecting a test resistor from the HV bus to ground. The charging station must detect this and abort charging. The relevant test reports can be downloaded from the test device via the WLAN interface. It is also possible to access the device via GSM for remote support.

Claims (10)

Mobile testing system of a car charging station comprising a vehicle with a built-in measuring device for testing the car charging station, characterized in that the testing system has a simulation of a communication error between the car charging station and the vehicle, wherein the reaction of the car charging station to the error makes it possible to determine whether predetermined processes, in particular a power interruption, are triggered thereby. Mobile testing system according to Claim 1 , characterized in that the vehicle has a battery pack by means of which the automobile charging station is tested. Mobile testing system according to Claim 1 or 2 , characterized in that the vehicle is an electric vehicle whose battery pack is used for testing. Mobile testing system according to one of the preceding claims, characterized in that the vehicle has a plurality of separable battery sets, wherein a first battery set is available for testing separately from a second battery set. Mobile testing system according to one of the preceding claims, characterized in that the testing system has a plurality of simulations which test a charging operation of the automobile charging station. Mobile testing system according to one of the preceding claims, characterized in that the testing system checks the automobile charging station and the vehicle. Mobile testing system according to one of the preceding claims, characterized in that the testing system takes into account a network reaction of the automobile charging station on the electrical network to which the automobile charging station is connected. Mobile testing system according to one of the preceding claims, characterized in that the testing system is capable of testing different plug systems and different automotive charging stations. Method for testing an automobile charging station with a vehicle which has at least one battery pack for propulsion, with the following steps: - connecting the battery pack to be charged to the automobile charging station, - carrying out a plurality of tests relating to the automobile charging station, including at least the interaction with the battery pack to be charged, and - discharging the battery pack charged for testing purposes, preferably by operating the vehicle, characterized in that the test system has a simulation of a communication error between the automobile charging station and the vehicle, wherein the reaction of the automobile charging station to the error is used to detect whether predetermined processes, in particular a power interruption, are triggered as a result. Procedure according to Claim 9 , characterized in that a mobile testing system with a monitoring device is used for testing, which is able to monitor the communication between a car charging station and a vehicle, to recognize information sent during the communication, to compare it with measured values of current, voltage and time for plausibility, wherein preferably a comparison is made with the current state of the vehicle or the connection, in particular the current connection between vehicle vehicle and the car charging station for plausibility.

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