Efficiency measurement of a high-voltage powertrain
Modern electrical powertrains are fully integrated, which makes instrumentation for measurement technology much more difficult. For this reason, the overall efficiency is the parameter for further optimization, since only electrical input power and mechanical output power have to be put into relation. In addition, data from the control units should also be included in the analysis so that efficiency and characteristic diagrams can be correlated. For this test the following components of the measuring system are used:
E-Mobility Basic Measurement System
- A HV Breakout Module 1.2 (HV BM 1.2), which is inserted directly into the HV lines between inverter and battery, measures current and voltage.
- A CNT4 evo measurement module measures speed and torque on the drive axles with appropriate sensors.
- The protocol converter XCP-Gateway pro connects the EtherCAT®-based (HV BM) and CAN measurement modules (CNT4 evo) and converts the data to XCP-on-Ethernet.
- With the eMobilityAnalyzer for vMeasure exp, the electrical input power (based on the HV BM measurement data) and the mechanical output power (CNT4 evo) are calculated in real time. With both values, the efficiency is also calculated online.
Vector Data Logger / Interfaces
- Thanks to PTP (Precision Time Protocol), a Vector Interface VX1000 captures data from powertrain ECUs in a time-synchronized manner and allows it to be included in the analysis.
Benefits
- Measurements directly in the HV cables increase the quality of the measurement
- Accurate analysis through real-time calculations
- Harmonized hardware and software simplifies the measurement setup and saves time during configuration
Verification of High-Voltage Electrical Systems
The electrical systems of modern electric vehicles comprise numerous different assemblies, which use high-frequency circuits to cause current and voltage ripples in the lines. These ripples can cause serious damage to the components and unpleasant noises. In order to ensure safety in all situations, the electrical system must also be verified in road tests, which requires extensive current and voltage measurements throughout the entire electrical system. To avoid excessive amounts of data, intelligent triggers should be used in this case. This test can also be easily performed with the components of the E-Mobility Measurement System.
E-Mobility Basic Measurement System
- With suitable HV Breakout Modules, which are inserted directly into the high-voltage cables, current and voltage are measured at various points in the vehicle electrical system.
- At locations where HV BM is not required, currents can also be measured with Hall-effect based LEM Sensor Packages connected to the AD4 OG100 measurement module.
- A protocol converter XCP-Gateway 4S pro acquires the data of the ECAT measurement modules, synchronizes them better 1 μs and converts them with 1 GBit/s to XCP-on-Ethernet.
Vector Data Logger / Interfaces
- A Vector Interface VX1000 additionally acquires internal data of the vehicle control units. Thanks to PTP, this data is recorded synchronously with the data of the measurement modules.
- Since the data is to be recorded on a data logger in the road test and numerous measurement channels with data rates up to 1 MHz have to be acquired, a high-performance Vector Smart Logger of the VP series with vMeasure log is used. Thus, up to 40 measured variables can be recorded with 1 MHz each. vMeasure log also contains the eMobilityAnalyzer function library. With this library, the voltage ripples are analyzed in real time and both raw data and analysis results are recorded.
Benefits
- Measurements directly in the HV cables increase the quality of the measurement
- Accurate analysis through real-time calculations
- Harmonized hardware and software simplifies the measurement setup and saves time during configuration
Testing the Operational Stability of High-Voltage Batteries
High-voltage batteries for electric vehicles have to withstand high mechanical stress during operation and especially in accidents to ensure safety. For this reason, extensive tests are necessary. With the E-Mobility Measurement System, such measurements, which include numerous different measured variables that all need to be correlated afterwards, can be easily implemented.
E-Mobility Basic Measurement System
- Accelerations within the high-voltage battery are measured with the HV IEPE3 FL1000 measurement module and IEPE sensors.
- Strains within the battery housing are measured with strain gauges and the HV STG4 BK20 measurement module.
- If additionally currents and voltages have to be measured, the HV Breakout Module 1.1 is suitable.
- Temperatures are measured during the test with the HV TH8 evo measurement module. On the outside of the battery housing temperatures are measured with the proven CAN measurement module TH8 evo.
- With a protocol converter XCP-Gateway pro the data of the ECAT measurement modules (HV IEPE3 FL1000, HV STG4 BK20 and AD4 OG100) are synchronized and the measurement data of the CAN measurement modules are bundled.
- With vMeasure exp and the eMobilityAnalyzer the measurements are evaluated.
Vorteile
- Simple connection of different measured variables
- Simultaneous measurements for accurate analysis
- Harmonized hardware and software simplify the measurement setup and save time during configuration
The Overall System
The Vector CSM E-Mobility Measurement System contains all necessary hardware and software to perform measurement and testing tasks for eMobility. Therefore it includes:
- Measurement modules, interfaces and software for the acquisition and synchronization of large data volumes of
- Analog measurement data from high and low voltage environments
- Measurement data from vehicle buses
- Data from control units
- Data logger for recording analog measurement data and data from vehicle buses
- The eMobilityAnalyzer for performance analysis and other calculations in real time
- Software packages for data analysis and data management
Highlights
- Decentralized, scalable online measurement system for test drives and test benches
- Multi-channel real-time power analysis with direct current and voltage measurement in HV cables
- Simultaneous acquisition of further physical parameters (temperature, acceleration, etc.)
- Synchronous acquisition of vehicle bus and control unit data
- Raw data recording and parallel powerful signal analysis
- Cloud-based data management with data mining
