Case Studies

HIL Battery Stack Simulator

Battery Stack Simulator for Hardware in the Loop (HiL) Testing of Electric Vehicles

Posted in Automotive, Battery Pack Test Systems, Embedded Development & Programming, Energy and Utilities, Green Technology, LabVIEW, Product Development, Test & Measurement Automation, Test Stand

Summary

 A battery stack simulator for hardware-in-the-loop (HiL) test systems is being produced by DMC to augment the capabilites of battery management systems (BMS) HiL test systems.  This system leverages DMC's vast hardware and software experience in Electric Vehicle (EV, HEV, PHEV) Battery Pack and BMS Testing.

HIL Battery Stack Simulator System Diagram

HIL System Diagram

HIL Battery Stack Simulator System Hardware

System Hardware

HIL Battery Stack Simulator Web Interface

Web Interface

Solution

The battery stack simulator system provides a turn-key instrument for simulating up to 96 battery cells voltages.  The system requires no initial configuration.  It uses a simple uniform command set which can be sent over CAN, serial RS-232, or TCP/IP Ethernet busses.  This functionality makes it ideal for integrating into existing HiL test systems, such as those available from d-SPACE, National Instruments, and other vendors.

Hardware-in-the-Loop (HiL) Battery Stack and Cell Simulator System:

The system is housed in a standard PXI chassis with an embedded real-time controller.  The controller provides serial and Ethernet ports while a PXI card provides a single CAN interface.  A series of up to 16 Pickering PXI 41-752, 6-cell battery simulator cards, are also housed in the single PXI chassis, providing up to 96 isolated battery cell voltages. 

Each voltage simulator output is galvanically isolated to 750VDC from chassis ground, and from adjacent channels.  Simulated battery cells can provide independently controlled output voltages from 0 to 7Vdc, settable with 12-bit ( <2mV ) resolution.  Each simulator can source up to 300mA of current, and sink down to -100mA, to emulate battery charging and discharging modes.   Each channel also has a separate pair of voltage sense lines to eliminate the potential effects of current loading and cabling resistance on voltage regulation and accuracy.  Load response time ~ 15 microseconds on each channel.  The output of the entire system of 96 cells can be updated in < 1 millisecond.

Optional Accessories for the HiL Battery Stack Simulator:

In most cases, the user will stack these cell output channels in series to emulate the actual stack of batteries connected to the BMS being tested within the larger HiL test system.  DMC can provide custom cabling and fixtures to route and aggregate the output channels to single connector defined by the user.

For simulating larger battery stacks, multiple battery stack simulators can be used in parallel over the same CAN bus by first using the web interface to configure independent instrument addresses.  This web interface configuration ability is included as standard with the system.  DMC can optionally provide custom single systems with higher channel counts if desired.

While independent read back of the actual output voltage or current on individual cell channels cannot be directly obtained from the Pickering PXI 41-752 simulator cards, DMC can provide an optional multiplexer system which can provide this functionality to the system using a single digital multimeter (DMM).  This is useful for measuring the leakage current into/out of each sense point on the BMS under normal operation and cell balancing conditions

DMC can also leverage experience and technologies from our BMS Test System to integrate functionality such as battery pack current and/or cell temperature sensor simulation. 

More Information on the HiL Battery Stack Simulator:

Contact DMC Sales for technical information, system options, or pricing.

Learn more about DMC's battery pack and BMS test systems and automated test stand design expertise.

Customer Benefits

The HiL battery stack simulator provides a turn-key, robust, and reliable system for adding high channel count simulated battery emulation to existing HiL test systems.

Technologies