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Exro unveils new application for Coil Driver motor controller: optimizing charging and V2G

Exro Technologies is introducing a new application for its patented Coil Driver technology—enabling EVs to fast charge seamlessly and provide electricity back to the grid regardless of power source or charger type.

Coil Driver is a next-generation dynamic motor controller that expands the capabilities of electric motors by enabling multiple dynamic profiles in operation. (Earlier post.)


Coil Driver, which replaces classic inverters, can calculate the system’s demands for torque or speed, and seamlessly switch the configuration to match the desired output in real time to optimize the power train electronically—extending operating ranges, and increasing operational efficiencies. A single motor can repeatedly change configurations on-the-fly and under demand to deliver optimal performance at low speed as well as at high speed.

Exro says that the Coil Driver technology can be used to deliver Level 1 to Level 4 charging capabilities, and to provide electricity back to the grid, with significantly less power electronics. This includes charging capabilities from renewable energy sources like solar and wind power. Exro has filed a new family of patents for this use case.

The recent patent filings raise Exro’s combined held and submitted patent portfolio to 36.

Currently, EVs require three different types of power electronics components to power the vehicles in motion and charge the batteries from the grid or renewable energy sources: a motor drive, on-board charger and external DC fast charger. Exro engineers found that the Coil Driver technology has the ability to replace all three components, significantly reducing the cost and complexity of deploying EVs and the charging infrastructure at scale.

Initial findings show that the minimal addition of voltage sensors to the existing Coil Driver enables this charging infrastructure use case.

Next, the Exro team will continue development to validate whether the Coil Driver can be a grid-connected energy storage solution and provide electricity back when needed for resiliency and vehicle-to-grid (V2G) applications. If successful, this will increase grid flexibility and enable commercial and heavy-duty EV fleets to seamlessly serve as mobile energy storage systems that could be tapped for back-up power.

Originally with the Coil Driver, the goal was to develop the perfect electric powertrain. With recent concerns around the realities of scaling fast charging infrastructure and sustainable energy use, we have continued research and development activities that further enhance and build on the Coil Drivercapabilities to solve issues beyond just the vehicle. Initial findings show that it works, and we’re excited to proceed to the next phase. With Coil Driver, Exro has the potential to make powering and charging EVs simple and cost-effective.

—Exro Chief Engineer Eric Hustedt



Sounds very good. If it holds up to all those promises, then even better.


They have patents for axial polyphase

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