Admotec Precision :High-performing Resolvers-Novel by Design

Given its capacity for sensing the position of rotating units in machines or motors, electrical resolvers hold immense value. In the context of EVs, they serve as the rotation angle sensor— accurately detecting the magnetic pole position of the drive motor and its rotational speed—to identify and control its position. They can also be used for the detection of steering angle in cars for driver assistant systems. The possibilities are limitless. As vehicles continue to push the limits of compactness and performance, there is a profound need for sleeker and better performing resolvers that are innovative by design. The typical design of a resolver is similar to that of a transformer with primary (at stator) and secondary (at rotor) coil windings. The coils, being thin wires, are amongst the weakest component of a resolver, with the one at the rotor having to withstand high operating temperature and rotational centrifugal forces. Besides, the rotor coil’s “bulkiness,” limits the speed of rotation which do not make them ideal in high speed, precision applications, i.e. EVs. With their patented Rotasyn series of resolvers, Admotec Precision offers a solution, which unlike their traditional counterparts, does not contain coils in its rotor and bypasses those inherent shortcomings to achieve speeds of up to 50,000 RPM.

Rotasyn resolvers have a 25 percent less failure rate than its conventional counterparts and are used in Formula One cars for their electric motors to quickly starting the vehicle, enabling it to function at peak power.

Subsequently, Formula E—the battery powered EV cousins of Formula 1—will soon employ Rotasyn resolvers as well.

Rotasyn resolvers were initially designed for the aerospace pioneer Airbus, in accordance with the industry’s strict quality and performance mandates. Admotec soon realized the value proposition that their novel resolvers could impart to verticals such as robotics, electro mobility, and industrial automation, and was quick to strategically diversify their target markets. “Our main aim is to make big volumes of simpler, affordable resolvers,” says Walter Wyss, President at Admotec. Prior to Admotec’s entry into other markets, resolver types available in the market came at a standard, fixed size. EV manufacturers had to design their motors in accordance to resolver dimensions while it rightfully ought to be the other way around. Admotec’s resolvers can come in sizes as small as half an inch, thanks to their coil-free rotors. Also, another key differentiator of the company is that they are able to create customized resolvers for specific uses cases based on their clients’ request.

The markets were quick to recognize Admotec’s value proposition. Wyss mentions that the company never had the need to actively invest in sales processes—sending out agents to potential customers’ locations, carrying demonstrations, pitching and so forth—as most of their clients came to them through word of mouth and the internet. After all, one need not think twice about the quality and performance levels of aircraft-grade products. Having established a strong presence in the European and Asian markets, the company is strategically expanding into the U.S. Looking ahead, Admotec is also working to roll out an even more novel resolver, the Multipole series, which will have customizable pole pairs in addition to coil-less rotors. Moreover, it will also come in even smaller dimensions. Multipole resolvers can have the same number of pole pairs of the motors that they are associated with gives even more refined and precise measurements while simplifying the control of motors. “We hope to bring Multipole range of resolvers to the market by the end of this year,” concludes Wyss.