The development of electric race cars requires extensive current, voltage and power measurements on the individual components in the electric powertrain in order to be able to design the power electronics. In addition, the overall system must also be analyzed in order to optimize efficiency and comply with regulations. This example shows how the necessary measured variables are aquired on the powertrain test bench and how power analyzations are executed in real time.
The team of the Duale Hochschule Baden-Württemberg (DHBW) in Stuttgart takes part in the international Formula Student design competition every year. For participation, the teams develop their own racing car.
The DHBW "eSleek" electric racing car houses an HV battery in the rear, which has 144 pouch cells and delivers a system voltage of 600 V and 7 kWh. Four inverters are integrated in their own housing on a cooling plate and are installed on the HV battery.
Acquisition of current, voltage and power calculation in real time for the development of the test bench and the inverter.
The eSleek electric race car has to be verified on a new powertrain test bench. For this, the necessary hardware and software for the test bench must be set up and optimized for the expected test requirements. Accurate current and voltage measurements are needed to configure the test bench.
In order to be able to complete all developments in the shortest possible time, it is essential that as much data as possible can be obtained for the further development of individual components as well as the entire powertrain using a lean measurement setup. In addition, the data should be able to be processed in real time to obtain immediate results from new settings on the inverter.
The test bench is equipped with components of the Vector CSM E-Mobility Measurement System for the acquisition of all necessary measured values and the performance analyses in real time.
This measurement setup can be used to test various theories of control concepts for inverter control, since precise parameter identification is possible. The acquisition of different efficiency maps enables the optimal designs of inverters and motors. The precise current, voltage and power measurements on the electric motors also allow optimum settings to be made here.
With the lean and modular measurement setup, which can be expanded at any time, all necessary current, voltage and power values can be obtained for the development of a number of components as well as for the optimization of the entire electric race car. The simple and synchronous acquisition of many measured values accelerates the development of the components.
CSM’s AD MiniModules of the AD CAN MM (MiniModule)-Series offer a wide range of applications for measuring analogue signals (voltage, current, pressure, flow rate, etc.).
The HV Breakout Modules (BM) are specifically designed for safely measuring directly from HV voltage power cables. Currents and voltages are measured directly and the raw data is acquired at up to 2 MHz per channel. With the Vector eMobilityAnalyzer software, which is optimally paired to the CSM HV Breakout Modules, real time power analysis is also possible.
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.
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.
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, 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.