Harness 48V Robotics: Boost Efficiency & Power in Industrial Automation

The demand for efficiency and cost-effectiveness in electrical systems is driving the adoption of 48V systems across industries. These higher-voltage systems offer a more optimal alternative to conventional 12- or 24-V architectures, particularly where high power delivery is essential. Industrial automation and telecommunications leverage 48V to power motors, actuators and other high-power equipment.

The advantages of using 48V systems include:

• Drive larger loads: unlike 12V systems, which struggle to meet modern power requirements

• Lower currents: higher voltage reduces current requirements fourfold

• Reduced power loss: lower currents mean less power loss, less heat to dissipate and higher efficiency; operating at a higher voltage

• Higher power density: integrated 48V solutions enable higher power density space, translating to further driving range and lower energy loss in clean energy systems

• Lighter cabling: thinner cables lower costs and reduce weight and space.

History of Power Distribution Systems

The 6V power distribution system became a practical standard for ignition and lighting in early automobiles, largely influenced by the widespread use of batteries at the time. Its simplicity and ease of use made it a popular choice. Although 24V systems were initially trialed — for example, in the 1912 Cadillac with its electric starter — the 6V system quickly gained dominance for most automotive electrical functions.

As automotive technology progressed, the demand for electrical accessories such as radios, heaters, and later, power windows, began to grow. This placed greater strain on the electrical system, highlighting the limitations of the 6V setup. A 12V system offered a key advantage: For the same power output, it required only half the current, which reduced the risk of overheating and allowed for the use of lighter, more manageable wiring.

The development of reliable 12V lead-acid batteries and alternators further supported the transition. With these components becoming easier to produce and more cost-effective over the years, the 12V system became the new standard. This led to the design and widespread adoption of compatible electrical parts, including lighting and motors that operated more efficiently at the higher voltage.

Struggles of Traditional Systems

AMT49100 3-Phase BLDC Gate Driver. (Image: Allegro)

Modern power demands cannot be met with traditional 12V systems, currently the mainstay of power delivery. The limitations of 12V systems become clear when considering factors like power loss and cable thickness.

As power demands increase, so do the currents within a 12V system in a linear fashion (P = V * I). This results in higher power losses along any wiring from the supply source to the load (Ploss = I2 * R).

These power losses manifest as unwanted heat and reduced system efficiency. Also, managing higher currents requires thicker and heavier cables, which adds weight and cost to system designs.

Industrial Automation Equipment

These 48V systems are increasingly used in industrial automation and robotics, offering higher power and improved safety over lower voltage systems. This includes components like motors, sensors, and gate drivers that are designed to handle the higher voltage and power demands of industrial applications.

The lower currents present in these systems reduce heat generation and potential fire hazards. Compared to higher voltage systems, 48V systems require less insulation, which can be a factor in compact designs. As they fall below the 60V safety limit, they are often considered SELV (safety extra low voltage), meaning they are designed to be safe for direct contact with unshielded equipment.

These systems offer enhanced efficiency and precision by reducing energy loss, enabling faster control and allowing for smaller, lighter equipment, increased dexterity and improved thermal management.

48V Solutions with High Efficiency

ACS37220 Low-Resistance Current Sensor. (Image: Allegro)

Allegro offers a broad array of sensor and power IC products ready for use in the design of 48 V systems across a myriad of robotic applications. The reduced power loss with Allegro’s 48 V solutions translates to a tangible increase in fuel economy for mild hybrids, significantly extending the range for all electrified vehicles and improving energy conversion efficiency in solar inverters.

Allegro’s motor and gate drivers provide precise and efficient control for 48V motors and actuators used in automotive and industrial automation, improving productivity and reliability. Their integrated current sensor IC supports high-voltage applications, while the digital position sensors deliver robustness and reliability to complement the motor drivers.

Autonomous mobile robots (AMRs) navigate dynamic environments for logistics and inspection, demanding precise motion, robust battery management and reliable obstacle detection. Allegro’s integrated motor drivers, magnetic sensors for positioning and load sensing, and efficient power management ICs enhance AMR performance, optimize energy usage and ensure operational safety in diverse settings.

Collaborative robots (cobots) work safely with humans, requiring precise motion, advanced safety features (SIL-2/3) and efficient power for articulated joints. Allegro’s 48V gate drivers, high-resolution position sensors and accurate current sensors enable robust joint performance, dependable braking and optimized power management for reliable human-robot collaboration.

Humanoid robots aim for human-like motion and interaction, demanding sophisticated actuation, dynamic balance and complex perception. Allegro’s advanced servo motor control, versatile multi-axis position sensing, and efficient power management technologies are fundamental for the intricate mechanics and demanding performance required by the numerous joints in humanoid robots.

Why Stop at 48V?

ACSEVB-EZ7-37220-100B3 Eval.Board for the ACS37220 Current Sensor (left). APEK85111KNH-02-T-MH Eval.Board for AHV85111 Isolated Gate Driver (right). (Image: Allegro)

The primary factor behind this limit was the safety standards that had to be met. Organizations such as UL and NFPA classify voltages below 60 V as SELV, considering them safe for human contact with unshielded equipment. Systems operating above 48V required more robust components and engineering to ensure adequate insulation and isolation, which increased overall cost and complexity.

Although 48V systems could be cost-effective, higher voltage systems often involved greater initial expenses due to the need for specialized components and wiring. Their design tended to be more complex, and implementation could be more costly, as specialized parts were either more expensive or demanded more intricate manufacturing processes.

Powering the Artificial Intelligence Revolution

Delivering low-latency AI responses requires substantial computing power, which significantly increases data center energy demands. To improve efficiency and reduce cooling requirements, data centers are transitioning from 12V to 48V power systems.

Innovations in power supply design support this shift, with future developments aimed at enhancing power supply performance and density. Consequently, data centers need to be equipped with high-performance servers, advanced cooling systems and robust power infrastructure to manage the workload effectively.

Data center operators are increasingly adopting energy-efficient technologies such as liquid cooling, renewable energy sources and server virtualization to reduce their carbon footprint and lower operating costs.

Conclusion

The shift from 12V to 48V systems is driven by the need for improved efficiency and reduced cooling requirements. In industrial automation, these systems offer higher power and enhanced safety compared to lower voltage options.

Components such as motors, sensors, and gate drivers are designed specifically for 48V systems, with a focus on safety, power output, mobility and cost savings. With a wide range of 48V products, Allegro delivers solutions that enable higher integration, as well as space and energy savings, allowing you to concentrate on your application.

Rich Miron is a Senior Technical Content Developer for DigiKey (Thief River Falls, MN). For more information, visit here  .