Reference design extend flight times for drones
Two circuit-based sub-system reference designs from Texas Instruments will help manufacturers add flight time and extend battery life to quadcopters and other non-military consumer and industrial drones.
Delivery companies want drones with enhanced battery life, and are testing delivery of parcels with drones. A recent IHS Markit study found that nearly half of drones in the market have an estimated battery life of less than 30 minutes, 35 per cent can fly between 31 and 60 minutes and the remainder can fly more than an hour under ideal flying conditions without additional payload.
The 2S1P Battery Management System (BMS) reference design transforms a drone’s battery pack into a smart diagnostic black box recorder that monitors remaining capacity and protects the Li-Ion battery throughout its lifetime. The reference design can add gauging, protection, balancing and charging capabilities to any existing drone design. The bq4050 multi-cell Li-Ion gas (fuel) gauge measures remaining battery capacity, while the bq24600 battery charge controller and a high-efficiency DC/DC converter are claimed to achieve high-efficiency power conversion efficiency.
Another barrier to increased flight time has been the inefficiency of turning a drone’s propellers. The reference design for drone electronic speed controllers (ESCs) will help manufacturers create drones with longer flight times and more smooth and stable performance, says the company. The Sensorless High-Speed Field Oriented Control Reference Design for Drone Electronic Speed Control helps electronic speed controllers achieve the highest possible efficiency with performance for speeds more than 12,000rpm ( above 1.2kHz electrical) including fast-speed reversal capability for more stable roll movement.
The design features the company’s InstaSPIN-FOC C2000, including an F28027F microcontroller for precise motor control and FAST field observer proprietary software algorithm that estimates the rotor flux, angle, speed and torque. Motor parameter information is used to tune the current control bandwidth. Unlike other techniques, the FAST sensorless observer algorithm is completely self-tuning, requiring no adjustments for proper operation and propeller control. The design also includes a 60V LMR16006 Simple Switcher DC/DC converter with low quiescent current to efficiently manage a drone’s Lithium polymer (Li-Po) batteries.