Renesas Electronics Europe today announced two motor control reference platforms designed to drive any 3-phase permanent magnet synchronous motors (PMSM), also called brushless ac motors. They enable engineers to reduce or even eliminate the time they would normally take to calculate motor parameters and evaluate the best tuning algorithm coefficients. As a result, they can rotate a permanent magnet ac motor in less than one minute.
The two new inverter kits revolutionise the integration of 3-phase motors in equipment. Both are based on Renesas' 32-bit RX family of MCUs, with one kit on RX220 offering 50DMIPS and the other on RX62T offering 165DMIPS. The RX220 inverter kit is designed for equipment requiring medium dynamics and a low-cost bill of material. The RX62T microcontroller integrates six operational amplifiers, six comparators, a floating point unit and two timer units to drive two 3-phase motors simultaneously. This kit provides the dynamics required to drive motors with a high level of accuracy.
Renesas has developed the two design tools based on RX62T and RX220 MCUs to respond to a challenge encountered by engineers: tuning the embedded software to the application requirements, especially for sensorless field oriented control algorithms. The inverter kits provide: Auto-tuning of the current proportional-integral (PI) coefficients: Kp, Ki; Identification of intrinsic motor parameters: Rs, Ls, Lm; and Real-time visualisation of the motor phase, current and step response.
Both kits include an intuitive PC graphical user interface (GUI), providing engineers with a ready to use inverter reference prototype that enables them to drive their own motors in a few clicks. They also feature a sensorless vector control algorithm, which is used to accurately control the speed and the torque. This algorithm uses flux weakening in order to achieve rotation speeds higher than the nominal speed of the motor.
Each kit contains the YROTATE-IT inverter board, a 24VDC permanent magnet AC motor, a CD-ROM including the embedded software source code, the PC GUI, the board schematics, the bill of materials, Gerber files, user manual, quick start guide and the power stage schematics/Gerber files.