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AC Power Cell
Product Description
The microGen AC Power Cell allows the user to more readily probe and connect to microGen’s AC
Power Generator, our piezoelectric vibrational energy harvester. Simply mount the board to a
vibration source and the device will generate AC power. Connect one of the supplied Power
Management Boards and you are ready to generate DC power.
Figure 2: AC Power Cell
How it Works
The heart of microGen’s AC Power Cell is the AC Power Generator, a high-Q piezoelectric
vibrational energy harvester with a fixed frequency that is based on a cantilevered beam design.
The piezoelectric layer in the device is compressed and elongated as the cantilever moves in
response to an external vibration source, which generates charge that can be extracted for power.
To generate power, the AC Power Generator can interact with vibrations in the environment in
two different ways. In resonant mode of operation, the AC Power Generator couples directly with
a matching fixed and stable input frequency from the environment. The resonant movement of
the cantilever allows power to be generated at fairly low acceleration levels, depending on the
frequency used. Alternatively, when a stable, fixed frequency is not available, the AC Power
Generator can be driven in impulse mode of operation, where the harvester responds to the initial
shock input, and then continues to vibrate as it rings down at its natural frequency, much like a
tuning fork or a bell struck by its clapper, until the next impulse shock is received. During the
time the harvester rings down, power is generated. The amount of power that can be extracted
under these conditions depends on the resonant frequency of the harvester, sharpness and peak
acceleration of the shock, and time between shock inputs. For further discussions on your
particular application, please contact microGen Systems directly.
