Expanding drone battery life is often seen as the Holy Grail of UAS. For one mega-corporation known best for its calculators, a pair of new circuit designs may just add up to more flight time and subtract from power limitations.
Texas Instruments recently released two circuit-based subsystem reference designs it says will allow drone manufacturers to make their battery packs and drone functions more efficient. What is a “circuit-based subsystem reference design?” To keep it simple, think of it as the battery pack’s “brain” that helps determine the best use of a Li-Ion battery’s available energy output.
According to a 2016 industry report by IHS Markit, around 50 percent of drones across the industry can hold an estimated battery life of less than 30 minutes; just over a third can hold out for up to 60 minutes – without payload.
“Flight time continues to be a top design challenge for recreational quadcopters and professional drones, especially those being used by companies for beyond visual line-of-sight operation,” HIS Stelios Kotakis said in a press release.
“Delivery companies want drones with enhanced battery life, and are testing delivery of parcels with drones to see how far they can go.”
TI’s 2S1P Battery Management System design “transforms a drone’s battery pack into a smart diagnostic black box recorder that accurately monitors remaining capacity and protects the Li-Ion battery throughout its entire lifetime,” a TI spokesperson stated.
Drone companies could use the design to enhance charging and gauging functions to existing models and achieve better efficiency to DC/DC converters.
TI’s Sensorless High-Speed Field Oriented Control Reference Design will, the company says, allow drone speed controllers to optimize efficiency at speeds greater than 12,000 rpm, “including fast-speed reversal capability for more stable roll movement.”
The design leverages a powerful microcontroller that uses a proprietary algorithm to estimate rotor flux, angle, speed and torque.
“Motor parameter information is used to tune the current control bandwidth,” TI officials explain in a press release. “Unlike other techniques, the FAST sensorless observer algorithm is completely self-tuning, requiring no adjustments for proper operation and propeller control.”