Chroma ATE Inc.

News Express
News Express
Improving the Quality and Safety of BMS
2018/12/08

Zero carbon emission has vastly become a worldwide trend as the popularity of electric vehicles (EV) begins to grow; the battery is being the key component. The performance and safety of battery packs is critical to the EV; its core battery management system (BMS) needs to be thoroughly verified to ensure the battery’s safety.

 8701

▲ Chroma 8710 EV / Bus BMS ATS

Chroma 8710 BMS ATS provides battery cell voltage and temperature sensor simulation for battery management system; furthermore, it offers applications suitable for testing the UUT (unit under test) to reduce the problems when performing the tests. The inspection functions equipped by the system include:

  1. The BMS circuit designed power conversion circuit converts the starting battery voltage to the power required by digital circuit. It is necessary to confirm the power status to make sure that the control circuit works stably.
  2. Measurement accuracy is required when using high voltage to measure the battery pack total voltage. This voltage is also one of the judgment criteria for enabling insulation resistance. The inspection of insulation resistance is critical to safety requires verification. Besides supporting the verification, the best way is to perform calibration first and verification later.
  3. The high/low side drive circuit controlling the high voltage relay is also one of the vital items for verification. When an error occurs, if the high/low side gate drive circuit is not active to disconnect the charge and discharge circuit, it could cause safety problem and result in burning the electric vehicle. Therefore, it is necessary to check if the high/low side drive circuit is running normally under all kinds of conditions.

Chroma has in-depth research on battery management system that makes the 8710 BMS Functional ATS capable of fulfilling the above test requirements to perform a fully automated test procedure and long hour battery pack charging/discharging test. 

Architecture Diagram of Chroma BMS

▲ Architecture Diagram of Chroma BMS 

A battery management system usually comprises of a current sampling unit (CSU), a cell supervisory circuit (CSC), and a battery management unit (BMU) via CANbus to transmit signals and issue commands for operation. When verifying a battery management system, it is imperative to verify the cell status monitored by CSC as well as the active/passive balancing circuit and current consumption. For CSU, the validation of current sampling accuracy is essential as it may affect the battery SOC, SOH and overcurrent protection. As to the most complicate BMU that controls the entire system, it verifies the data returned from CSU and CSC. 

Integrating with the test systems customized by Chroma can perform high quality functional verification on battery packs and battery management systems with provision of applications suitable for testing the UUT to reduce the trouble occurred during testing. For more information on the 8710 BMS ATS, please visit Chroma’s website below and list your needs and contact, we are happy to be of service.

 More information please check on Chroma battery pack production line test