
Hall effect position sensors for high-speed electric motor applications
TDK introduces the new Micronas HAL 302x 2D Hall Effect sensor family for position measurement in high-speed applications. It has been developed in accordance with ISO 26262 to meet the demand for sensors for interference field robust motor position detection in automotive and industrial applications.
The product family initially consists of two members, HAL 3020 and HAL 3021, with differential and single-ended sine and cosine analogue outputs for standardised angle computatrions by external microcontrollers or ECUs. The HAL 3021 is suitable for demanding high-speed applications such as electric power steering, electric motors (E-axis), electric brake boosters and electromechanical brakes (EMB). The HAL 3020 is the right choice for cost-efficient applications such as electric pumps or electric valves. For this purpose, the sensor can be combined with TDK’s Micronas embedded motor controller portfolio to provide precise and safe motor control.
All sensors in the new product family can measure a full 360° angle of rotation by evaluating the vertical magnetic field (FC) components. While the HAL 3020 uses an array of three horizontal Hall elements, the HAL 3021 uses six Hall elements. Both sensors are capable of compensating for external DC and AC magnetic interference fields (ISO 11452-8). By suppressing harmonic interference in the stimulation signals using internal calculations, a simple and low-cost two-pole ferrite magnet in an on-axis configuration (end-of-shaft) is sufficient to measure the absolute angular position. The inherent noise field robustness eliminates the need for expensive magnetic shielding and the use of stronger magnets. This allows more flexibility in the development and production of next-generation electric motors used in hybrid and electric vehicles. Other applications include electric brake boosters, electromechanical brakes (EMB), clutch and transmission actuators and starter/generator systems.
In terms of sensor robustness to static and dynamic mechanical alignment errors, such as off-axis displacement, air gap variation and tilt, the HAL 3021 leads the industry, the manufacturer promises. This ensures highly reliable and efficient field-oriented motor control throughout its lifetime. To reduce the effort on the controller side, the chip-level sensor can compensate for the most important sensor- and system-level deviations, such as sine and cosine amplitude deviation, offset error, (absolute) 0-angle and orthogonality error.
The HAL 302x sensor family is defined as Safety Element out of Context (SEooC) ASIL C ready according to ISO 26262 and supports system level integration up to ASIL D. The sensor integrates various functional safety monitoring functions that help to increase diagnostic coverage and simplify external monitoring of safety-related functions on the ECU side. The sensors operate in the junction temperature range of -40 °C to +170 °C and are available in a small eight-pin SOIC8 SMD package. Samples are available now and production is scheduled to start in the first half of 2024.
https://www.micronas.tdk.com/en
