Electrified Powertrain Systems Testing - APL

// Electrified Powertrains

Alternative Powertrains — Meeting Current and Future Challenges

We started the first tests of alternative powertrains as early as 2003, initially with electric motors including power electronics, and then with high-voltage batteries. In the course of development in recent years, our testing portfolio has expanded enormously: from the complete HV network (power supply system via charging station), to onboard chargers, HV batteries, inverters, electric motors, transmissions, differentials, shafts, and oil supply investigations.

Control room for climate chambers for batteries and ‘back-to-back’ tests

Climate chamber

High frequency measurements on an osciliscope

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In order to stay ahead of rapid development curves, we are constantly optimising our technical testing equipment and measuring technologies. We invest a lot of money in the internal and external training of our employees. Only with highly qualified engineers and employees can we realise new, extremely complex test conditions. Our goal is to be able to reproduce the complete spectrum of alternative powertrain concepts at any time – from simple components to highly complex HV composite test benches, including charging infrastructure.

Project Support

One contact person for the entire project
Setup design and support
Commissioning
Test procedure programming and testing
Test procedure optimisation and control
Measurement data evaluation, analysis and assessment
Troubleshooting and problem solving
Coordination of departments and processes
Project timeline and budget monitoring
Daily status report
Interface management — external and internal
Test result documentation and presentation

Mechanical Construction

Individual solutions for every type of construction and connection
Wheel, cardanshaft, VKM simulation, high speed dynamometers
Up to 5 dynamometers
Vibration-optimised test bench construction
Back-to-back construction with and without climate chamber/hood
0° shaft alignment
Rotation speeds up to 24,000rpm
Torques up to at least 2,500Nm

Electrical Construction

Production of wiring looms and either direct connection or via contactor boxes
Tests with your or an APL converter
Currents (DC) of 600A /1200A (with parallel connection) with high dynamics (0 è 100A in 0.3 ms)
Electrical power (DC) of 150kW / 300kW (with parallel connection)
Maximum voltages (DC) of 1,000V
Dynamic DC supply (source/sink)
Temperature chamber with safety technology

Measurement Technology

Electrical power measurement; specific testers for electrical machines and complex test benches; high-precision measurement technology
HBM T12 torque measurement with various measurement ranges
Power measuring devices
Storage oscilloscopes
Vibration measurement technologies (e.g. Reilhofer or Müller BBM)
Sniffer measuring device
Insulation and winding resistance measurements
Motor testing equipment (Schleich GLP1‑e HV)
HV-safe evaluation units
Rotor measurement by means of 3D measuring machine
Positioning of measurement technology close to test specimen
High reproducibility
Continuous recording of measurement values up to 1kHz
Postmortem measurement data

Additional Aggregates

Additional measuring technology and conditioning can be used project-dependently; media conditioning is adapted to the requirements
Independent conditioning LE / EM (-40°C — + 130°C)
Oil conditioning
Circulating air conditioning (-40°C — + 180°C) by means of climate chamber or climate hood

Automation

Control engineers for prompt, project-specific adjustments
Flexible control
Automated conditioning and mapping measurements (with reference point monitoring)
Restbus simulation
Battery simulation:
- With an electrical simulation model, the charge and discharge of Li-Ion batteries can be modeled. This way, within the test setup (e.g. hybrid drive), the Li-ion battery is completely replaced by a controllable DC voltage supply.
CAN restbus simulation for battery control unit
Driving resistance
Automated driving
Time-optimised testing

“In our sector there are never two projects which are exactly the same. This ensures variability and keeps things exciting.”

Lisa Z., Project Engineer

Durability Testing

Various loads are tested here across the entire lifetime, validations of electric powertrains are carried out (in accordance with relevant standards and customer specifications) and bearing/rotor tests are implemented.

Highly dynamic situations can be simulated using DC power supplies and test rig machines. In addition, automated running of characteristic diagrams and intermediate measurements are performed. The basic conditions — for example, influence of ambient temperature (-40°C — 150°C) or humidity — can be easily adjusted. It’s also possible to integrate special conditioning, aggregates, or special measurement technology at any time.

Functional Investigations

For functional testing, many different tests are automated or performed manually. The goal is to determine and test the full performance spectrum, temperature development, behaviour in case of failure, and basic functions of a prototype.

Usually, these tests are very time-consuming and require a lot of fundamental knowledge, as they’re neither tried and tested specimens nor standard procedures. The tests include mapping measurement, maximum characteristic curves (including S1 operation), short-circuit and no-load characteristic curves, back-EMF measurement, transient load behaviour, thermal investigations and others. Often, these tests are also used to calibrate a test item or to check the application.

Environment Simulation

During the development of a new component, it’s necessary to check safety and durability, detect weaknesses and develop appropriate measures. For example, the influence of great heat, cold or moist air is tested on the test specimen (waterproofness, penetration of objects/dust and vibrations).

Type Approval, COP and EOL

At the end of the development process, we are able to realise type approval with the most diverse requirements for speeds and power.
Conformity of Production (COP) is carried out during the production cycle in order to ensure key performance of the electric machine as determined during type approval.
End-of-line (EOL) tests are primarily used for quality assurance and are carried out at the end of a product manufacturing process. We can offer these tests during the development process.

Back-to-Back / Back-to-Front

Test procedures, in which two test items are mechanically connected directly or via gears, can be operated in climatic chambers by means of a climatic hood, or without conditioning of the ambient air.

Simulation Vehicle / Road / Driver

The display of driving profiles — for example, legal or customer-relevant cycles — is important for testing e‑drive components.

The real-world efficiencies, the total energy demand, the thermal behaviour and the durability test play a major role here.

Investigating Coolants and Lubricants (e‑fluids)

Coolant and lubricant functionality can be tested on existing electrical axles and electrical dynamometers. Depending on requirements, we can provide pure electric motors, hybrid drives, transmissions or even entire vehicles for testing on one to four-dyno test benches or chassis dynamometers.

2WD / 4WD

Our test bench concept is so flexibly designed that

complete vehicle drivetrains (4‑machine superstructures incl. battery or battery simulation), two-machine superstructures (e.g. for axle tests) or
test bench setups can be tested with only one dynamometer for pure electric motors. As a rule, we can realise any and all customer requirements.