The optimal design of inverters is necessary for increasing the range per charge and performance of electric vehicles. The inverter is the link between the battery and the electric motor and plays an important part in the electric powertrain. This application example shows how power and efficiency calculations are performed on the inverter and how the measurement setup can easily be expanded for further measurements.
When converting DC from the battery into three-phase AC, which is used to regulate the three-phase electric motor, part of the energy is lost due to PWM switching performance and waste heat in the inverter. These losses must be kept as low as possible. The efficiency of the inverter is a suitable parameter to evaluate changes in design and software. Ideally, the efficiency of the inverter can be directly correlated with the efficiency of the associated electric motor.
Measurement of electrical input power and electrical output power for the calculation of the inverter efficiency.
To determine the inverter efficiency, the electrical input and output power must be measured synchronously and in a high-voltage safe manner. The measurement must be carried out with high data rates and phase accuracy in order to have suitable data for a precise calculation. At the same time, temperatures in the inverter must be measured in order to analyse the effects of thermal changes on the performance. If the efficiency of the electric motor is also to be calculated in parallel, the mechanical output power must also be measured.
The solution for this measurement task is found in the perfectly harmonized Vector CSM E-Mobility Measurement System, which combines precise measurement modules and powerful software.
With the Vector CSM E-Mobility Measurement System, the calculation of the overall efficiency can be done in real time. Due to the robust and compact measurement modules, the measurement can be performed both on the test bench and in road tests. The test setup is shortened to a few components, which reduces the time required for the test setup and increases the quality of the measurement.
Furthermore, the Vector CSM E-Mobility Measurement System allows easy integration of additional measurement modules for further measurement variables, e.g. temperatures.
Here you find the complete application report for download as PDF.
The HV Breakout Modules (BM) have been specifically designed for safe measurement applications on cables carrying high voltage. Current and voltage are evaluated and the power calculated online in the module.
XCP-Gateway is the interface between the data acquisition software (e. g. vMeasure, CANape®, INCA®, Vision® ...) and the EtherCAT® measurement modules from CSM. It includes an EtherCAT® master and an XCP-on-Ethernet slave.
Safe temperature measurements with thermocouples on high-voltage components: the high-voltage-safe temperature measurement modules are specifically designed for the reliable acquisition of temperatures in electric and hybrid vehicles.
CSM's measurement modules HV PT MiniModule (HV PTMM) and the HV PT test bench module (HV PT-TBM) allow precise temperature measurements with PT100 and PT1000 resistance sensors in a high-voltage environment.
The CNT evo is a high-precision measurement module designed for measuring frequencies, pulse widths, incremental displacement measurements, rotation angles, position measurement, event counting and period measurements.
Electromobility continues to gain momentum. Various energy storage, drive and charging systems pave the way to electric mobility. The development of high-voltage batteries, inverters and electric motors places high demands on measurement technology in order to obtain the right results for further optimization. Together with Vector Informatik, CSM has developed a measurement system that leaves nothing to be desired.
Swift configuration of measurement chains: CSMconfig is the reliable configuration software for all CAN and EtherCAT® based measurement modules from CSM. The clearly arranged and easy-to-use user interface allows an easy setting of all measurement parameters. This helps speeding up the measurement setup considerably.
vMeasure exp, developed by Vector Informatik, is an easy-to-use software tool for the acquisition and analysis of measurement data that can be used in combination with all CAN- and EtherCAT®-based CSM measurement modules. CSMconfig was integrated directly to ensure swift configuration.