A key safety function of any battery management system (BMS) is the measuring and reporting of current and overcurrent; this function is provided by a high voltage (HV) sensor. As an expert in mechatronics, Marquardt has developed an HV sensor that offers improvements in the BMS, as Ellen Marquardt, Product Management Power and Energy Solutions, 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.“
From insulation resistance to 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 the 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 Ellen 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.” Marquardt 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-are down to the smallest detail,” says Ellen Marquardt.
Flexibility through scalable design
The 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”, emphasizes Ellen Marquardt.
The HV sensor will 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. The HV sensor can be used in all these sectors – and thus make the mobility of the future better, safer and more sustainable.