Texas Instruments has developed a new current sensor for electric vehicles that improves motor control precision and can extend driving range from existing batteries.
The TMCS2100-Q1 sensor is designed for installation inside an electric vehicle's traction inverter, the core power electronics unit that manages energy flow between the battery pack and the motor.
In electric cars, the traction inverter determines exactly when and how much electrical energy passes from the battery pack to drive the vehicle. Texas Instruments, a semiconductor manufacturer headquartered in Dallas, Texas, engineered the component to measure electrical current with high accuracy. When current measurement accuracy increases, the vehicle controller can manage motor power production with far greater precision.
Current measurement and motor precision
Sensors are critical components in electric powertrains, monitoring electrical flow so onboard computers can adjust energy delivery. Even small inaccuracies in current measurement can directly degrade the driving experience. Small errors in reading electrical current create torque ripple, causing fluctuations in the rotational force sent to the motor.
These torque fluctuations make acceleration feel less smooth to the driver. In addition, measurement inaccuracies cause a portion of the electrical energy to turn into heat rather than motion, while increasing operational noise from the electric motor.
Dual-axis sensing technology
In existing current sensors, small and lightweight coreless designs make the components vulnerable to mechanical vibrations from the road. These vibrations cause the physical position of the sensor to shift, generating measurement errors during vehicle operation.
To solve this issue, the TMCS2100-Q1 measures magnetic fields horizontally and vertically at the same time. This simultaneous dual-axis measurement allows the sensor to compensate for errors caused by positional movement. Texas Instruments said this approach makes the sensor 20 times more precise than existing single-axis coreless sensors.
Impact on electric vehicle efficiency
The TMCS2100-Q1 keeps measurement error under one percent even if its position shifts by up to 0.4 millimetres. While 0.4 millimetres is a small movement, exact current measurement is vital in modern electric vehicle powertrains, especially in high-voltage 800-volt electrical architectures that transmit large amounts of power in very short durations.
By giving vehicle manufacturers improved motor control, the sensor enables smoother acceleration, quieter motor operation, and higher overall energy efficiency. The increased efficiency can allow electric vehicles to cover longer distances on the same battery capacity. Furthermore, the compact design of the sensor will enable automakers to build smaller and lighter traction inverters for future electric models.
