It is a ready-to-use, flexible solution for applications such as electric vehicles, drones, and industrial automation, where high current output and compact design are essential.
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The advent of circular and extremely compact motor control reference designs for high-current brushless motors marks a significant advancement in modern engineering. These designs are crucial for various applications, from electric vehicles and drones to industrial automation and robotics, where efficiency, precision, and space optimization are paramount. By integrating high-current capabilities into a compact form factor, these innovative designs not only enhance performance but also reduce the overall footprint, enabling more versatile and efficient use of space. The circular layout facilitates better thermal management and electromagnetic compatibility, ensuring reliable and robust operation even under demanding conditions. As industries increasingly pivot towards more sustainable and efficient technologies, the importance of such cutting-edge motor control solutions cannot be overstated.
The EVLDRIVE101-HPD by ST Mircroelectronics is a highly compact three-phase inverter designed for brushless motors. It integrates the STDRIVE101 gate driver and the STM32G071KB microcontroller. This combination offers versatile control methods, including Field-Oriented Control (FOC) and trapezoidal control, with sensors and sensor-less options. It is particularly suited for battery-powered three-phase applications demanding high output currents. Operating within a voltage range of 18 V to 52 V, the inverter is adaptable to various battery configurations. The STDRIVE101, a triple half-bridge gate driver, ensures efficient and reliable motor control. Central to the system is the STM32G071KB microcontroller, based on the Arm Cortex-M0+ architecture, featuring 36 Kbytes of SRAM and 128 Kbytes of Flash memory. This provides ample resources for complex motor control algorithms and application-specific firmware.
The power stage utilises STL220N6F7 MOSFETs, known for their low Rds(on) of 1.2 mΩ and high current handling capacity. This configuration allows the inverter to support output currents up to 15 Arms, translating to a power output of up to 750 W, ideal for high-demand applications. The compact design has a circular footprint of just 50 mm in diameter, facilitating easy integration into various mechanical setups. A fast power-on circuit that connects and disconnects the battery significantly extends battery life by minimising idle power consumption. An external turn-on/off trigger provides a low-power standby mode, which is crucial for battery-operated systems. The board has an input connector for Hall-effect sensors and encoders, enhancing its flexibility in different motor applications. Back-EMF (BEMF) sensing circuitry and a current limiter with an adjustable reference ensure safe and efficient motor operation under varying loads.
Protection features include thermal shutdown to prevent overheating, Undervoltage lockout (UVLO) to prevent operation under unsafe voltage conditions, and overcurrent and reverse bias protection on the power stage outputs. Reliable and redundant overcurrent protection is achieved through VDS monitoring. The board features an STDC14 debug connector and supports direct firmware updates via UART, simplifying development and maintenance processes.Its robust features ensure reliable performance and longevity, making it an ideal choice for demanding brushless motor applications.
ST Microelectronics has tested this reference design. It comes with a bill of materials (BOM), schematics, assembly drawing, printed circuit board (PCB) layout, and more. The company’s website has additional data about the reference design. To read more about this reference design, click here.