CSM Xplained Archive

Currents must be measured at many points in the HV electrical system of modern electric vehicles: Be it to analyze charging and consumption processes or to verify protective measures against shield currents. The precise investigation of high-frequency current components requires a wide bandwidth in measurement, and instrumentation in particular can present users with challenges.

• Which currents must be measured at which points in the HV electrical system?
• What requirements are placed on the measurement technology?
• With which methods can currents be measured?
• How can current measurements be performed on test benches and in vehicle testing?

Technological development in the field of on-board charger (OBCs) is currently experiencing a push toward higher integration along with other power electronics of electric vehicles. On-board charger in vehicles have to cope with different grid standards and charging networks worldwide. AC charging verification and OBC testing is therefore a particularly critical step for vehicle series release. The correlation and synchronization of measurement technology integrated in the vehicle with measurements outside the vehicle is also becoming increasingly important.

In this web seminar you will learn:

• How are on-board charger tested and AC charging processes verified?
• How are mobile measurements are performed?
• What power and efficiency analyses are important?
• How CSM supports this development with the new HV BM 3.1 OBC Breakout Module and an customized, airline-grade measurement case for measurements between charging station and electric vehicle.

DC and AC voltages in the HV environment are characterized by peaks and dips as well as superpositions and have a significant influence on the interaction of all components. To ensure proper operation of the entire system, regulations set limits and must be verified.

• What are the typical characteristics and interactions of HV voltages in the vehicle electrical system?
• What must be considered when using measurement technology for voltage measurement?
• With which measuring instruments can HV voltages be reliably acquired?
• How can voltage measurements be performed in road tests and on the test bench?

The testing of electric drive systems requires a wide range of measurements and analyses of electrical power in the most varied degrees of detail. Depending on the application, extensive analyses including efficiency determinations may be necessary for the optimization of e-axles - while other contexts, such as the determination of consumption values, tend to benefit from independently performed power measurements.

Key points of the web seminar:

• What the different requirements are for power measurement and power analysis.
• When power measurements in combination with compact data loggers are advantageous in road tests.
• Why independent power measurements with black box systems can also be useful on the test bench.
• What advantages a modular, scalable and expandable measurement system offers.

Temperatures play a major role in the performance and safety of vehicles with electric, fuel cell or hybrid drive systems. If the temperatures in components such as the HV battery deviate significantly from their ideal range, performance losses, accelerated wear or even total failure are the result. Accordingly, temperatures must be measured intensively at many points.

• What is the significance of temperatures in electromobility?
• How can a HV-safe measurement chain be built - from the temperature measurement point to the data acquisition unit?
• What are the options for temperature measurement for the various applications?
• What advantages and disadvantages do the various options offer?
• How can hundreds of temperatures in HV batteries be measured efficiently and safely?

The performance, operational reliability, fast-charging capability and aging of HV batteries depend crucially on comprehensive and good thermal management. For this, it is important to know the temperature profiles within the battery that occur in different operating states in as much detail as possible. Battery management systems (BMS) have the task of operating the battery within its "comfort temperature".

The development of high-performance thermal management systems requires extensive thermal analyses.

• What is the significance of temperatures for the operation and safety of HV batteries?
• What has to be considered for temperature measurements in HV batteries?
• What special requirements does thermal characterization and validation of simulation models place on the measurement setup?
• How can hundreds of temperature measurement points be precisely acquired, even between battery cells?

Accelerations must also be measured safely and precisely in high-voltage environments. For example, HV batteries are used as load-bearing elements in the vehicle frame. Accordingly, extensive investigations of fatigue strength are required on high-voltage components, but also within the HV environment.

• Where do accelerations need to be investigated within an electric vehicle?
• How can accelerations be measured HV safe for system and user?
• What challenges arise in acceleration measurement and how can they be solved?

Testing of durability poses great challenges for the measurement equipment to be used, especially in the high-voltage environment. For example, the so-called "swelling" is to be investigated on HV battery cells. For this purpose, strain gauges are primarily used whose output signals, some of which are very small, must be recorded precisely, reliably and safely at a high voltage potential.

• Which critical points in the electric vehicle typically have to be examined for their durability?
• How can the signals of bridge-based sensors such as strain gauges be acquired in a HV-safe manner?
• What challenges arise in particular with strain gauge measurements at HV potential and how can they be solved?

The reliable detection of strains and temperatures in the e-mobility environment poses a major challenge - the very small amplitudes of the measurement signals are many orders of magnitude below those of the system voltages of several hundred volts used. And the wireless transmission of these measured variables is also massively hampered by the enormous electromagnetic interference generated by respective components of electric vehicles themselves.

In this episode of CSM Xplained, we present exciting solutions for the reliable and precise measurement of strain gages and temperatures. Find out more about high-voltage safe, wired and also innovative wireless solutions for strain gages and temperatures - this time in interview format with telemetry expert Gerhard Spitz from AXON Systems.

The use of classic measurement computers in supervised test driving is problematic in many respects. Staff supervision costs, occupant safety during extreme driving maneuvers and operability under driving conditions are just some of the disadvantages of using laptops and other display-supported end devices. In this episode of CSM Xplained, we show how the measurement computer can be dispensed with in many applications and replaced by a robust and connected data logger.

In this web seminar, we will show you in compact 30 minutes:

• What problems and risks can the use of measurement computers in road tests entail?
• How can intelligent data logger solutions leave the supervised measurement computer unnecessary in road tests?
• Which tools and features can connected data loggers use to compensate for relevant functions of the measurement computer?

The electrification of mobility in particular has intensified competition among vehicle manufacturers. At the same time, the amount of data generated in modern vehicles is exploding as a result of progressive digitization. Extensive recording of fieldbus data, e.g. from control units by means of powerful data loggers, is becoming increasingly important.

To remain competitive, field tests and fleet tests must be as reliable and efficient as possible. For this purpose, worldwide data transmission of the recorded measurement data by means of modern wireless technologies is essential. In addition, it must be possible to manage large vehicle fleets easily and conveniently.

Learn how to meet these challenges in this issue of CSM Xplained.

When recording measurement data in fleet testing, the security of your data plays an essential role. An overall system that works reliably and at the same time protects data sources and recordings from unauthorized access, is required. In this episode of Xplained, we show you how this can be implemented with our system.

Key points of the web seminar:

• How can you ensure that measurement recording is performed reliably and correctly?
• To what extent is your recorded data safe from "data theft"?
• How is your measurement data transmitted completely, error-free and tap-proof?

The electrification of the vehicle powertrain poses major challenges for the interaction of the individual components. In order to optimize both - the acoustics and the performance of electric vehicles, high-voltage and NVH measurement data must be acquired synchronously.

In this web seminar we show the problem in the acoustics of electric vehicles and the solutions for eMobility and NVH analysis:

• Challenges in electric vehicle acoustics
• Synchronous acquisition of NVH and power data on the powertrain
• Correlation of NVH and power analyses