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AFPM generators operate, in principle, by orienting the magnetic flux, which creates the power, in the direction of the rotating shaft attached to the blades of the turbine. This differs from the most widely deployed method of generating power, Radial Flux Permanent Magnet (RFPM) which orients the magnetic flux away from the spinning shaft in all directions.

The Clean Energy AFPM generator is patented and has many advantages over legacy RFPM technologies, and other AFPM generators.  The Clean Energy generator is by definition a coreless stator AFPM machine that has an internal stator and twin external permanent magnet rotors.  The permanent magnets are positioned in an alternating pole array along a non-magnetic supporting structure.  This produces a completely coreless structure as a finished product.  It is this coreless configuration that eliminates the ferromagnetic material, i.e. steel laminations and SMC powders that can build up in the stator that can cause eddy current and hysteresis core losses.  Because of the absence of these core losses, the Clean Energy generator operates at a much higher efficiency than its RFPM counterpart.

The coreless AFPM generator also benefits from its ultra-low start-up torque. Rated at less than 5 pound feet of start-up torque, Clean Energy generators can actually be turned by hand at all power levels, including our 500kW generator, and produce usable power.  This is a practical advantage as the amount of wind that is required to start up the Clean Energy Generator is lowest in the industry allowing turbines that are built around the Clean Energy Generator to produce more usable power sooner and increase ROI.

Weight of the generators is also drastically reduced.  Less material used in the generator brings the weight of our products down 2-3 times versus similarly rated products from competitors.  Not only does this make for easier installations due to handling the weight at height, but also for cheaper turbines to be produced through reduction in shipping costs, to less expensive towers required to hold the turbines.

Another patented aspect of the Clean Energy generator is the inner-rotor versus outer-rotor design.  Historically, AFPM generators have been manufactured by mounting the rotor magnets onto the outer housing of the generator which spins relative to the stator which is in turn attached to a fixed mounting point.  By reversing this configuration and fixing the stator to the housing, and rotating only the magnets on the inner rotor, the rotating force does not need to move the housing of the generator and can be applied to making usable power.  This is a much more efficient concept based off of a simple concept.

At the heart of these generators is the magnetic technology itself.  The Clean Energy generator uses only the best Neodymium magnet material in order to achieve the highest power outputs.  Through long term supply agreements with major rare earth metal vendors, Clean Energy has secured its magnetic material which guarantees its quality and reduces its price point. 

Another patented technology exists in our revolutionary self-contained cooling system.  When the generator is operating and producing electricity, it generates heat. As heat increases, generator efficiencies decrease. To solve this problem, our generators include a patented, closed-loop, liquid-cooling system. This drastically reduces the associated wear that high-temperatures can cause, and thus improves the life-span of our generators.

Another unique patent and advantage is MSO™.  Multi-stator output effectively works to drastically lower the torque, during start-up and generating RPM, by adding in, or taking out stators during operation.  The advantage of our axial flux design is that we are able to easily stack rotors and stators into a single casing, something we do on our higher output generators or based on customer specifications.

By stacking the rotor and stator sections into a single housing unit, larger generators can be created.  More specifically, the Windro 500kW generators are simply stacked 100kW generators. The advantage to stacking the generators is that each individual rotor can be turned on/off via a remote software system so that initial start-up torque is much lower than conventional generators in all RPM conditions.   In wind turbines this works to solve the problem of bump starting the generator using external power sources. The variability of the generator output also allows for greater flexibility with the turbine. Each circuit is drawn from the generator independently and combined using circuitry in the local transformer.

Efficiency 

The efficiency rating of our generators is upwards of 85% across the RPM spectrum.  This is a radical shift and improvement over legacy technologies that can be as much as 60% lower, when not operating at rated RPM.  This is one of the most crucial components to consider when designing or improving a current turbines efficiency, and our ratings can help achieve the goal.  Overall turbine design efficiency can be increased by as much as 5% to 10%, thereby producing greater amounts of power for the end user and reduced ROI. 

Low RPM (Custom RPM) 

The number 1 failure point in any turbine is the gearbox.  The gearbox works to take the low rpm’s produced by the input blade and increases the RPM to match the requirements of legacy generators, some as high as 1800 RPM. 

Our generators are available in standard RPM’s of 200, 250 and 400 depending on the model.  And in many cases, we can customize the RPM even further for our customers depending on their needs and budget.  The added value of direct drive increases efficiency, lowers operating costs, and can eliminate the need for a gearbox or lower the ratio required. 

Low Torque 

A key advantage in our technology is the naturally low torque our generators require to turn them.  Able to be spun by hand in all sizes up to and including our 500kW model, this allows for quicker power production and lower cut-in speeds.   Torque is an important consideration in every design, please contact us for individual generator specifications. 

Robust

Our generators are rugged to ensure that turbines operate in even the harshest of conditions.  Our extended temperature generator is unprecedented in the industry, with ratings as low as -50°C versus the industry standard of -20°C.  

High Power to Weight Ratio 

We have some of the lowest weight in the industry, for equivalent power outputs, by up to 5 times.  Weight is an important factor to consider when integrating designs on rooftops of buildings and for mechanical integrity of the turbine hub.  This also allows support structures to be made lighter and cheaper further reducing costs. The form factor design of our generators allows for installation ease, thereby minimizing upfront costs and minimizing the end user’s environmental footprint. 

Coreless for Low Maintenance 

With our AFPM generator, cogging problems are completely eliminated as the technology has no core on the stator coil, thereby minimizing down time and reducing maintenance costs over the life of the system.