By John McHale
EL SEGUNDO, Calif. - Engineers at International Rectifier (IR) introduced a hybrid motor-control module for aircraft applications that does not need software development to run, cutting out hours of code development and removing DO-178B certification burdens.
The IRMCT3UF1 is an integrated high-reliability (HiRel) hybrid motor-control module enabling digital, sensor-free vector control of permanent magnet motors. Based on IR’s iMOTION integrated design platform, the new module combines digital control, analog interface, and power stage, streamlining time-to-market and increasing design flexibility to accommodate drive-system changes in high-reliability applications.
“Compared to complex DSP (digital signal processing)- or microprocessor-based solutions that require position sensors and sophisticated programming, the iMOTION platform simplifies motor-control design for aerospace systems,” says Michael Toland, power modules product marketing manager of International Rectifier’s HiRel Products. “It is estimated that up to one man-year of motor-control system design can be saved by eliminating the laborious code development associated with digital motion control.”
Other features of the motors that make them ideal for aircraft applications are their small size and low weight, Gendron says. They also help in fuel efficiency because the smaller form factor means more of them can be used, he adds.
The drive is software-free, which means the only FAA certification that is a concern is DO354, the hardware one, says Robert Gendron, executive director of hi-reliability products. The lack of software dependence removes the DO-178B concerns from the customer, he adds.
The module can be quickly configured to specific applications using the iMOTION ServoDesigner tool that facilitates drive parameter modification via memory-mapped registers, IR officials say. The control functions are contained in a powerful, preconfigured Motion Control Engine (MCE), and its algorithm accommodates motor parameter variation for compatibility with a variety of brushless DC and permanent-magnet AC motors, while creating robust field-oriented control.
In contrast to conventional motion-control circuits, the new HiRel iMOTION module is a greatly simplified solution featuring high efficiency, reduced size and EMI suppression, company officials say. It is built into IR’s rugged, high-density plastic ring frame package, and screened to various test methods of MIL-STD-883 for operation in severe environmental conditions. Less than half the size of a discrete solution, the module combines digital controller, memory, external interface, gate drivers, and six power MOSFETs into an eight-square-inch, 2.5-ounce package.
The IRMCT3UF1 provides accurate high-performance speed and torque control without commutation or position sensors. Optimized sinusoidal current control enables current start-up sequencing and low-loss space-vector pulse-width modulation (PWM) for smoother start-up and minimized torque ripple for maximum motor efficiency.
For more details on the iMOTION platform, see www.irf.com/product-info/imotion.