September 03, 2019 by Tyler Charboneau
Linear Labs’ engineering advantage revolves around performance. The company designed the HET motor to provide two-to-five times more torque than commercial motors within the same-sized package.
The HET is a high-efficiency powerhouse made for a variety of applications. As with most electric motors, an inverse relationship exists between torque and RPM. When RPM rises, most motors deliver increasingly less torque. This is a performance limitation; it also places restrictions on suitable applications. Conversely, traditional electric motors deliver higher torque at lower RPMs.
Linear Labs’ latest motor technology sidesteps these common hurdles by providing exceptional torque at all RPM ranges. This makes the HET ideal for EVs, scooters, and wind turbines–instead of limiting its range of uses.
The Hunstable Electric turbine brings a unique design and benefits to the table:
3D circumferential flux 4 rotor platform
Torque production at up to an 8:1 gear ratio
Directional magnetic arrangement
Peak power density exceeding 7.0kW/kg at 3,000 RPM
Lower operational DC voltage
Up to 30% less copper usage
A compact design
Long magnetic tunnel region, with max torque at all positions
This three-dimensional design creates four torque producing areas with equal polarity. The motor’s magnetic forces are applied in the direction of motion, aiding in power production. Efficiency is superb across the board, though it peaks notably at lower speeds.
Its low operating voltage allows the inclusion of a smaller DC link capacitor and lower switch ratings. This arrangement saves space and cost. The HET also has a higher efficiency curve than commercial motors. This high-efficiency design extends the range of corresponding vehicles. Accordingly, 100% of available copper is relegated to energy conversion.
Aside from the torque advantage offered, the Hunstable Electric Turbine is a consolidated solution for EVs. The turbine is an integrated platform, requiring fewer supplemental components for effective power delivery. A typical EV may include six main engine components when using a commercial motor. In contrast, a HET-equipped EV only needs four:
HET motor
AC to DC converter
Controller
Battery
Diagram of a HET-equipped EV, including key components. Image courtesy of Linear Labs.
Typical commercial EVs require both a gearbox and a DC to DC converter; HET usage eliminates the need for these components. The motor requires no geared reduction thanks to its efficiency at various RPM ranges. This simplification lessens the chance of component failures and slashes long-term maintenance costs. Linear Labs claims these benefits have no performance drawbacks.
According to Brad Hunstable, CEO of Linear Labs, “...the drive system of the future is a direct drive system…” Many of today’s motors rely on RPM-driven designs that are complicated and expensive. Linear Labs asserts their HET motor won’t be more expensive to produce than its commercial counterparts. Additionally, existing manufacturing processes are suitable for producing this emerging class of motors.
The HET motor offers many key improvements and boasts impressive compatibility with varied applications. While this technology is impressive, we can only imagine where the industry will soon move as a whole. If the future is indeed directly-driven, the HET design is poised to be a superb asset.
