The RX111 motor-control kits from Renesas are inverter reference solution kits designed to drive any three-phrase permanent magnet synchronous motor (PMSM), or brushless ac motors. Based on the company’s 32-bit RX family of 3-V microcontrollers (MCUs), they deliver 50 DMIPS at 32 MHz. The kits provide up to 7 A at 24 V dc, and have been tested with more than 30 different motors. In addition, an external power stage is available to be fully-compatible with existing RX220 and RX62T inverter kits. The kits further provide auto-tuning of the current proportional-integral (PI) coefficients (KP and KI); identification of intrinsic motor parameters (RS, LS, LM); real-time visualization of the motor phase, current, and step response; and dynamic modification of the pulse-width-modulation (PWM) frequency and control loop.
A graphical user interface (GUI) provides a ready-to-use inverter reference prototype, enabling users to driver their own motors in a few clicks. A sensorless vector control algorithm is used to accurately control speed and torque by using flux weakening to achieve rotation speeds higher than the motor’s nominal speed. Two flux estimator blocks help ensure flexibility in terms of motor types and application requirements.