German mechatronics solutions supplier Marquardt has announced developing a high-voltage (HV) sensor that offers improvements in the battery management system (BMS) of an electric vehicle. The BMS measures and reports current and overcurrent scenarios in an EV and leverages a high-voltage sensor to accomplish this goal.

Marquardt claims that its HV sensor provides increased safety for electric cars, fuel cell vehicles and stationary battery systems, where this technology can be implemented.

Ellen Marquardt, Product Management Power and Energy Solutions, Marquardt Group, explains, "Our new HV sensor not only measures very precisely, but also extremely quickly. This allows the system to respond immediately. This advanced technology has the potential to save lives in the event of an accident, making it a crucial factor in ensuring the safety of e-mobility."

Utilising a pyroswitch
If the sensor detects an overcurrent, it immediately triggers the pyroswitch, which then disconnects the system from the power supply within just five milliseconds. The HV sensor also continuously monitors the resistance between the chassis and EV battery to ensure it is within the desired range.

While this may be simple for static systems, it is a technical challenge for dynamic systems, like vehicles, explains Marquardt. "Due to the constant motion of vehicles, the voltage rises and falls rapidly, making it easy for incorrect resistance values to be measured. We offer a solution with higher measurement accuracy than conventional sensors' she added.

The company says that it has developed a proprietary algorithm for the insulation resistance measurement, and also delivers the HV sensor with its own software. "We are expanding our portfolio with this self-developed HV sensor, ensuring that the battery management system is state-of-the-art down to the smallest detail," she said.

Scalable Design
As per the Marquardt Group, its HV sensor can be used in electric cars, hybrid vehicles, fuel-cell electric vehicles, and stationary systems. Depending on the application, the HV sensor meets the required safety functions from ASIL A to ASIL D. One advantage of the HV sensor is its scalable design, which makes it possible to combine different functionalities. "This allows us to adapt the sensor to the respective customer's requirements from specification to production - and in a cost-effective manner", emphasises Marquardt.

Marquardt's latest HV sensor is slated to go into series production in 2023 and will serve a diverse customer base, including passenger cars, trucks, off-road vehicles, agricultural and construction machinery, and even aviation.