Vector E-Vehicle User Manual

E-Vehicle and Charging Station – It’s Better If They Get Along Right Away

Smart Testing of Conformance and Interoperability

The availability of a dense network of fast charging stations is a decisive factor for the acceptance of e-mobility. Ensur­ing interoperability between e-vehicles and charging stations still tends to be underestimated today, so comprehensive
tests in this area are indispensable to vehicle manufacturers. Until today, common practice has been to test vehicles
manually using as many real charging stations as possible. Considering the increasing number of different e-vehicles and
charging stations, this way of doing things is now reaching its limits. Manufacturers and suppliers can only reach their
goals more quickly and cost-effectively and with considerably greater test coverage if they use a suitable test system
that enables automated conformance tests based on international standards.

The use of DC-charging with high power is planned for the
fast charging of e-vehicles (EV) along highways and express­ways. Public charging like this is incomparably more com­plex than charging an EV at home in your garage using a
typical wallbox where power flows through your own elec­tricity meter. Primarily in Europe and the US, the CCS
(Combined Charging System) serves as the general stan­dard for DC fast charging. A variety of different companies
and organizations have together brought the CharIN
(Charging Interface Initiative e.V.) to life, whose task is to
further develop the CCS and establish it as a global stan­dard for the charging of battery-powered EVs. The different
areas of responsibility are divided among five focus groups,
to which members bring their expertise and workforce. The

Focus Group Conformance Test & Interoperability is, among
other things, responsible for creating specifications for test
hardware and software that can be used by e-vehicle and
charging station manufacturers for automated testing of
their products for CCS conformance.

From Charge Park to Global Testing Events

Using test systems that correspond to these specifications,
e-vehicle and charging station manufacturers are now able
to test their products without laborious manual testing.
Manual testing, which has been common until now, will no
longer be feasible in the future due to the increasing num­ber of EVs and variety of different charging stations. For
100% test coverage, every EV would have to be tested with

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every conceivable charging station (Figure 1). Large OEMs
maintain “charge parks” with a selection of representative
charging stations for this purpose. Testing events where
respective manufacturers of e-vehicles and charging stations
converge to test their product against as many other prod­ucts as possible are also held across the globe on a regular
basis. In more basic cases, events like this only concern the
ECU electronics level, but they can also involve entire vehicles
and charging stations. This takes lots of effort, incurs high
costs, and exceeds the abilities of smaller manufacturers
and suppliers in particular.
This is why the future belongs to conformance tests that
companies can easily execute at their own laboratories.
Developers test their actual product against a test system
corresponding precisely to the specifications of the CharIN
Focus Group Conformance Test & Interoperability on the
hardware and software side (Figure 2). This is the only way
the complexity of CCS can actually be handled. The CCS is
a powerful system that deals with a variety of different
charging modes for DC and AC charging and must take as­sorted standards into account at the same time, such as
DIN70121, ISO 15118 and IEC61851-1.

Technical Article / September 2020

Figure 2: Performing a conformance test on a real e-vehicle with a
CCS test system, in this case from Vector.

with incorrect content and the like. Errors cannot be inserted
intentionally through manual tests with real counterparts,
as only good cases are tested in general here. Message
sequences and content, charging parameters and other
marginal conditions can only be flexibly modified through
simulation using test systems.
As a longer-term goal, the CCS is striving toward conve­nient charging following the plug-and-charge principle.
Here, the vehicle need only be connected to the charging
station with a plug, after which all the necessary actions –
such as identification, billing, negotiating electricity rates
etc. – are carried out automatically. In the future, there will
also be product certification that documents that a vehicle
can be charged at any certified charging station. This certi­fication is being promoted by CharIN. During the certifica­tion process, test companies and test partners will be in­volved and will subject the test object to all tests prescribed
by CharIN.

Figure 1: Ensuring interoperability of e-vehicles and charging
stations – now and in the future.

Stress for Charging Electronics: Inserting Errors

Using automated conformance tests, fault cases can also
be covered systematically. In this context, for example, you
have to check whether the charging electronics also exhibit
behavior specified by the standard if the counterpart does
not comply with the required timing or sends messages

Instructions for Standard-Compliant Test Systems

Testing a variety of different functions begins at develop­ment departments long before the official test date. The
documents provided by CharIN contain detailed instruc­tions on how the hardware and software of a suitable test
system can be implemented, which functions are required
and which out of hundreds of possible tests are necessary.
Anyone who has the corresponding expertise and wants to
make the effort can develop a CharIN CCS Test System
(CCTS) (Figure 2). This being the case, there isn’t just “one
CCTS” – individual implementations can differ from one
another in many details, be it the user interface on the soft­ware side or the hardware equipment depending on the
System Under Test (SUT). The power unit permits a large
number of possible variations, for example. Using a power
unit with comparatively low charging power is sufficient for
testing communication. In practice, however, customer
requirements in this area differ significantly from one

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