Induction Motor Position-Sensing Solution Replaces Encoders

Nov. 6, 2023

Magnetic-free dual-coil technology can create a high-resolution, precise, and reliable solution for motor position sensors used in robotics, industrial, and medical devices.

Alix Paultre

Related To: Electronic Design

The need for accuracy and precision in industrial systems continues to grow as more advanced processes are implemented in manufacturing, among other sectors. The devices used in position sensing on the assembly line or factory floor must be able to handle extreme environmental conditions such as humidity, high temperature, and vibration.

Addressing this need, Renesas Electronics' recently released inductive position sensor (IPS) technology creates motor position sensor ICs with a high level of accuracy for robotics, industrial, and medical applications. The position-sensing technology uses non-contact coil sensors, replacing costly magnetic and optical encoders currently used in motor-control systems.

Offering absolute position sensing, high speed, accuracy, and reliability, the proprietary IPS technology employs sensing elements consisting of copper coils etched on a PCB to detect the position of a metallic target. IP-based products can operate at 600 krpm (electrical) and detect the position right at startup, while the propagation delay is less than 2 μs.

The sensor technology also enables autocalibration and linearization features to ensure consistent performance throughout the motor’s operational life. The Vernier-based dual-coil sensor technology supports a resolution of up to 19 bits and an accuracy of up to 14 bits, and it can operate reliably in harsh environments with high temperatures, dust, moisture, vibration, and electromagnetic interference.

Immune to stray fields, the induction sensors are require no maintenance, and they're less susceptible to error than magnetic sensors. Solutions based on IPS technology create differentiated motor position-sensor ICs for industrial applications that are robust, highly accurate, and cost-effective. It supports UART, ABI, and I²C communications interfaces, and will be backed by a complete toolchain that includes dedicated software for user customization and precision optimization.

The technology portfolio is part of the company's Winning Combinations, solutions that work together seamlessly to bring an optimized, low-risk design for faster time-to-market.

Alix Paultre | Editor-at-Large, Electronic Design

An Army veteran, Alix Paultre was a signals intelligence soldier on the East/West German border in the early ‘80s, and eventually wound up helping launch and run a publication on consumer electronics for the US military stationed in Europe. Alix first began in this industry in 1998 at Electronic Products magazine, and since then has worked for a variety of publications in the embedded electronic engineering space. Alix currently lives in Wiesbaden, Germany.

Also check out his YouTube watch-collecting channel, Talking Timepieces.