GreenVirtueCorp

Wireless sensors are sometimes located so remote that replacing batteries is not an option. Such applications often turn to energy harvesters. Energy Harvesting (EH) also known as energy scavenging for small electronic and low power electrical devices uses ambient energy to provide electrical power, eliminating dependency of battery power, thus they work autonomously for years. 

In general, applications by EH sources like light, vibration, RF, thermal or chemical/biological are not only low power (in micro to milli watt level) but they are at low voltages. Since most current wireless sensors, including power conversion circuits, require 2+ volt range, we have two possible ways to meet those application requirement. One, the harvested voltage must be boosted and transfer energy as efficiently as possible. Two, the application requirement must buck down to subthreshold level to match with the harvested voltage.  Since second option involves newer chip designs and it is complex, the current proposal will focus on the first option. 

In theory the systems and methods using multiple energy generators connected to the same energy harvesting circuit should result in more energy. However, if multiple sources are attached to the same circuit in an attempt to produce more electric energy, the energy loss will be very high and there will be less energy harvested than if a single source was used. The main reason for this is impedance mismatch in circuits that consumes all or a part of generated resource. Also, further losses occur due to the destructive electric signal interference results in less energy available. For these reasons, traditional single energy management circuit can only handle one energy generator at a time. 

We offer a solution that allows all EH sources to be stored at once by using an efficient energy management technique.