Highly accurate and robust induction motor position sensing technology

Renesas Electronics Corporation has released a cost-effective IPS technology for highly accurate motor position sensor ICs for industrial, medical and robotics applications. Using non-contact coil sensors, the position sensing technology can replace expensive magnetic and optical encoders now typically used in motor control systems that need absolute position sensing, high speed, accuracy and reliability.

The proprietary IPS technology from the company uses sensing elements comprising copper coils etched on a PCB to detect the position of a metallic target. Unlike heavy magnet-based sensors, the IPS products can perform at 600Krpm (electrical) and detect the position right at startup, while the propagation delay is less than 2μs, making them excellent for motors with high rotational speeds. Furthermore, the sensor technology supports auto-calibration and linearisation features, providing consistent performance throughout a motor’s operational life.

Based on the Vernier principle, the dual-coil sensor technology supports a resolution of up to 19 bits and an accuracy of up to 14 bits, which makes them superior to comparable products available. The robust sensor technology will function reliably in harsh environments, where they can be exposed to high temperatures, dust, moisture, vibration and EMI. The induction sensors are immune to stray fields, need no maintenance, and are less susceptible to error than magnetic sensors. These advantages make induction position sensors a more attractive option than traditional optical encoders or magnetic-based encoders, which tend to be heavier and more expensive.

“Our induction position sensor technology represents a significant leap forward in motor position sensors,” said Jan Leuckfeld, senior director, HPC Analog (Sensor) Division at Renesas. “They will enable us to provide differentiated motor position sensor ICs for industrial applications that are robust, highly accurate and cost-effective.”

“Position sensors for factory floors must endure extreme conditions such as humidity, high temperatures and vibration,” said Ulrich Marl, key account manager at Lenord+Bauer, a Renesas customer and a leading manufacturer of encoders for industrial systems. “Through our collaboration with Renesas, we’ve integrated IPS-based technology into our encoder portfolio to ensure reliability and safety while reducing downtime in critical applications.”

The induction position sensor technology will support typically used UART, ABI and I²C communications interfaces, ensuring seamless integration into industrial networks and enabling real-time monitoring and data analysis. Also, the new sensor technology will be backed by a complete toolchain that includes dedicated software for user customisation and precision optimisation. The company plans to combine the new sensor with many compatible devices from its portfolio to provide a wide array of Winning Combinations. These Winning Combinations work together seamlessly to bring an optimised, low-risk design for a faster time to market.