Erallo’s Energy Harvesting Capabilities

The concept of harvesting energy is not a new one: it has been of interest for over 10 years and has been used to produce sufficient energy to self-power telemetry, small devices, and charge batteries or capacitance devices. Energy Harvesting (EH) devices typically use either vibration (rigid body motion) or thermal gradients. Vibration power harnessing depends on sustained vibrations of a specific frequency and vibration amplitude. This is ideal for helicopter parts such as rotors, gears or rotor hub assemblies; however, it may not be ideal for static parts, such as the airframe. In recent years, the state of energy harvesting technology has become increasingly sophisticated. Ultra low power microprocessors, efficient EH storage technologies (such as super capacitors and thin-film batteries) have become more cost-effective and are now widely implemented.

Erallo has successfully and innovatively applied energy harvesting to a variety of its networks. Erallo’s expert engineers work with customers to determine if EH is applicable for their sensor network solution. In addition to generating power through EH, all of Erallo’s sensor networks are designed to create energy efficiency, wherever design parameters permit, using an Intelligent Power Management System.

Energy harvesting is a viable solution for developing autonomous system and networks, both for wireless and wireline deployments. The state-of-the art in Energy Harvesting devices and techniques is increasing each year and is expected to be more prevalent in the coming years. Whenever design requirements permit, Erallo is committed to using cost effective, robust and innovative energy harvesting technologies in our network design solutions. With continuing advances in EH, the reality of long-life, maintenance free, zero power sensor network systems is possible.

Example of a simple Energy Harvesting System

Erallo’s Design Steps for EH Powered Networks:

Erallo follows a thorough design protocol for adding EH to a sensor network. This protocol includes the following steps:

1. Determine best EH choice for network: centralized or distributed
2. Characterize and calculate network power requirements
3. Identify ambient energy sources for harvesting
4. Calculate total EH power generation (should meet or exceed needs of the sensor network system)
5. Choose appropriate EH Transducer type for maximal energy from the available ambient energy sources
6. Determine conditioning circuitry for EH Transducer: Transducer signals are not initially produced at the proper voltage for sensors, microprocessors and transmitters; the appropriate signal conditioning must be determined.
7. Choose EH storage device: EH transducers don’t have the ability to store energy, and since they can’t continuously supply power, the EH storage device must be carefully considered.

• EH storage capacity: Erallo ensures that the capacity of the storage device exceeds the needs of the system when the ambient power is absent (i.e., solar energy at night) and that it recharges rapidly when power is restored.
• Cutting-edge battery options: Traditional rechargeable storage devices have limited charge/discharge cycle life, charge current and voltage requirements, so Erallo provides cutting-edge battery options including, solid state and thin film batteries
• Maximize EH storage device lifetime: Rechargeable batteries can wear down over time, so choosing the correct device and adding specialized circuitry to minimize fluctuations in load current can maximize its life.

Erallo’s Dynamic Power Management:

In addition to strategically applying EH technology, Erallo consistently applies Dynamic Power Management techniques to minimize power consumption and maximize power efficiency for every sensor network.

“Energy Aware” Microcontrollers: The basis for Erallo’s Power Management System is selecting sensor nodes that have “energy aware” microcontrollers specializing in minimizing power consumption. By using sensor nodes with ultra, low power processors, Erallo is able to run its advanced power management control algorithms that include: no polling loops, check input power and battery charge level and change wireless transmission duty cycles, as well as MPPT (maximum peak power point tracking)

Erallo’s Intelligent Power Management Module: Erallo’s Power Management module was designed to manage, conserve and reduce system and sensor power usage. Power or settings to the sensors can be trigger when a pre-determined event is detected by a sensor or can be based on a pre-defined schedule. Communication is one of the most energy intensive processes involved in a sensor network. Erallo reduces communication related energy needs by initiating communication only when a pre-defined event is identified; using sophisticated data aggregation protocols; and using specialized and efficient data sampling algorithms. Intelligent power management drastically reduces the battery usage and eliminates the need for larger, heavier batteries.