The Changing Landscape of High RPM Torque Measurement

Mobility concepts have changed dramatically since the onset of the combustion engine and the eventual introduction of the electric motor. These innovations have, in turn, impacted test bench and torque measurement technologies. Two particularly prevalent trends in classical fields of application are higher revolutions per minute (RPM) and dynamic torque measurement.

In this article, HBM explores the landscape of high RPM torque measurement while outlining some of the challenges and changes expected in the future.

High RPM Torque Measurement: Automotive

The three classical markets requiring high RPM torque measurement are the automotive, aerospace, and industrial processing sectors (component testing, turbine monitoring, etc.).

In the automotive sector, torque is a fundamental metric in measuring vehicle performance as a ratio of power-to-weight and as a function of the engine type, gearbox functionality, transmission, etc. Generally, torque measurement in the automotive market deals with a manageable RPM range. A typical diesel engine operates across an approximated 3,500 – 5,000 RPM while a gasoline engine may reach as high as 6,500 RPM. These values are confined to low- and mid-range consumer vehicles.

High RPM torque measurement becomes a prerequisite in the automotive space when it comes to high-end sports cars operating at around 9,000 RPM, competitive markets (i.e. Formula One), and performance vehicles with comparatively high speeds of 18,000 RPM. Demand for more efficient and higher performance vehicles has also heightened the need for high RPM torque measurement of integrated components like turbochargers. Turbines in a typical turbocharger can surpass 100,000 RPM at standard operation.

Testing high-performance engines, gearboxes, drivelines, transmissions, and components in this new, high RPM torque measurement landscape requires a robust solution.

High RPM Torque Measurement: Aerospace

High RPM torque measurement in the aerospace sector is a routine requirement in both turbine testing (approx. 22,000 RPM+) and high-speed gearbox measurements (approx. 30,000 RPM+). Various application fields in the aerospace market reach high RPM ranges, subsequently affecting torque measurements for standard components like gears, bearings, fuel pumps and seals. Typical aerospace applications requiring a high RPM torque measurement solution include:

• Aero-engine auxiliaries (alternators, starters, etc.)
• Compressors and turbine turbo-shaft testing.
• Helicopter transmission testing.

Future Challenges in High RPM Torque Measurement

Similar RPM ranges are reported as standard in the electrical drives sector, with some synchronous electrical machines ranging up to 25,000 RPM which are already available today. This application is particularly challenging for torque measurement as innovative electrical drive systems (i.e. E-axle drives) are consistently changing in terms of inertia and size. Classical industrial test benches are also affected by higher RPM capabilities, particularly with respect to electrification.

Electrification underlies the primary driving factors for constantly increasing RPM capabilities and dynamic torque measurements. The fundamental concept is to achieve a higher power density by increasing the speed of the motorized drive without commensurately increasing the size of the device. This is the most challenging aspect of modern torque measurement for higher RPM; a challenge that underlies each of these classical markets.

Torque Measurement Solutions from HBM

HBM is a world leader in the field of high-speed torque measurement for demanding areas of application. We offer a suite of dynamic solutions to assist in your high RPM measurements and to meet the challenges of modern testing.

If you need any more information, simply contact a member of the HBM team today.

Related content