Current sensor offers energy control to future-proof EVs/HEVs

February 19, 2014 // By Paul Buckley
Isabellenhütte has introduced a current sensor that satisfies the key battery management criteria for future-proof vehicle design.

Using the company's experience in battery management for electric and hybrid vehicles Isabellenhütte developed the current measurement system for batteries in alternative drive concepts.

The ICB-M current sensor features two mutually independent measurement channels, which are galvanically isolated and have a separate power supply.

The first channel, a high-precision current sensor, ensures high measurement accuracy through direct shunt-based measurement. The measurement values are determined within a 24-bit range. The current sensor features an output rate of 1 kHz. CAN 2.0 is used for communication, with a data rate of up to 1 Mbit/s. A CAN Database Container (DBC) facilitates rapid system integration. The ICB-M provides a digital measurement channel (Channel 1) as well as an analog Channel 2, completely galvanic isolated from the first, that relies on a magnetic measurement method and analyses the magnetic field generated by the current flow in the conductor, providing a voltage-level output in a measurement range of +/- 300 amperes.

The ICB-M makes current measurement safer, even in the event of malfunction. The two measurement channels provide redundancy in the system – the variable to be measured can be calculated in different ways. When one channel drops out, the missing measurement value can still be ascertained with the alternative channel.

The redundancy enables on-board diagnostics (OBD) and also has cost benefits versus selective solutions. A second measurement system must be integrated to ensure that conventional sensor modules have room for error. But the affordable ICB-M comes with this feature included to eliminate the cost of an additional measurement system to ensure redundancy.