LEM Introduces Three Phase Current Sensors for Automotive Traction Inverters


LEM, a provider of innovative and high quality solutions for measuring electrical parameters, has introduced a range of three-phase current sensors for automotive high voltage traction inverters in xEVs - the HAH3DR series. These open loop Hall-based current sensors measure the magnetic field generated by the primary current flowing in a busbar inserted in the sensor slots and deliver a galvanically isolated output proportional to the primary current. The HAH3DR sensors can measure bidirectional DC and AC currents with output at 0.5V for -IPN, 2.5 V at 0 A and 4.5 V at +IPN.

With a ratiometric output, the current sensors can share the same power supply as the Analog to Digital Converter (ADC) and prevent further error during the signal conversion due to reference mismatch.

The tightly controlled assembly and calibration of a LEM designed magnetic core with a LEM proprietary ASIC results in low offset, excellent linearity and high global accuracy specified over temperature and lifetime.

The HAH3DR family has been designed to achieve fast response time, high bandwidth and withstanding high dV/dt levels required for motor control applications. Because the mechanical integration of the sensor is key for a compact assembly, LEM has developed two distinct designs within the HAH3DR family:

  • The HAH3DR S07/SPx versions are specifically designed to fit within an inverter module such as the Infineon Hybridpack Drive, with lead pitch, busbar opening, mounting holes, package height and press-fit connection to the gate driver board.
  • The HAH3DR S0x versions are designed to fit on thick busbars and are available with a cable connector for direct connection of the sensor output to a control board which may be located further away from the inverter. The HAH3DR S00/SP4 offers a through hole connection to the gate driver board if located right on top of the sensor.

Features & Applications:

  • Capable of measuring bidirectional AC and DC current
  • Galvanic isolation
  • Ratiometric output
  • Up to 1200 A (1500 A ongoing development)
  • High global accuracy, high linearity, low offset specified over temperature and lifetime
  • Fast response time, high bandwidth
  • Rugged against high dV/dt
  • Compact footprint for IGBT and SiC inverter power modules
  • Various mounting options
  • Automotive qualified
  • For traction inverters
  • Quality Managed products suitable for safety relevant applications

Click here to learn more about the HAH3DR Series.