Energy Scavenging From Low-Frequency Vibrations by Using Frequency Up-Conversion for Wireless Sensor Applications

By Haluk Kulah, Khalil Najafi. IEEE Sensors Journal, 2008

370 citations recorded by the source corpus.

This paper presents an electromagnetic (EM) vibration-to-electrical power generator for wireless sensors, which can scavenge energy from low-frequency external vibrations. For most wireless applications, the ambient vibration is generally at very low frequencies (1-100 Hz), and traditional scavenging techniques cannot generate enough energy for proper operation. The reported generator up-converts low-frequency environmental vibrations to a higher frequency through a mechanical frequency up-converter using a magnet, and hence provides more efficient energy conversion at low frequencies. Power is generated by means of EM induction using a magnet and coils on top of resonating cantilever beams. The proposed approach has been demonstrated using a macroscale version, which provides 170 nW maximum power and 6 mV maximum voltage. For the microelectromechanical systems (MEMS) version, the expected maximum power and maximum voltage from a single cantilever is 3.97 muW and 76 mV, respectively, in vacuum. Power level can be increased further by using series-connected cantilevers without increasing the overall generator area, which is 4 mm2. This system provides more than an order of magnitude better energy conversion for 10-100 Hz ambient vibration range, compared to a conventional large mass/coil system.

Subfields: Electrical and Electronic Engineering, Mechanical Engineering

View Paper: https://www.semanticscholar.org/paper/b46864d333bed445553541b26c6cf1ada64d9af4

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Electrical and Electronic Engineering

1. Lihua Tang
2. Yaowen Yang
3. Chee Kiong Soh
4. Chengkuo Lee
5. Huicong Liu
6. Tzeno Galchev
7. Hanseup Kim
8. Lei Gu

In Mechanical Engineering

1. Lihua Tang
2. Yaowen Yang
3. Chee Kiong Soh
4. Chengkuo Lee
5. Huicong Liu
6. Tzeno Galchev
7. Hanseup Kim
8. Lei Gu

Citations in the corpus

• A Vibration-Based Electromagnetic Energy Harvester Using Mechanical Frequency Up-Conversion Method (2011, methodology): “The proposed structure uses a mechanical frequency up-conversion mechanism to increase the performance of the system while eliminating the use of extra magnetic materials in the structure, hence simplifying the device assembly when compared with those of [13] and [14].”
• Piezoelectric MEMS Energy Harvester for Low-Frequency Vibrations With Wideband Operation Range and Steadily Increased Output Power (2011, background): “One reasonable solution is to employ frequency-up-conversion mechanism [54], [55] which converts low-frequency ambient vibrations into high frequency vibrations to improve the power generation for such MEMS piezoelectric EH device at low operation frequency.”
• Piezoelectric buckled beams for random vibration energy harvesting (2012, methodology): “Other research groups have employed a frequency up-conversion technique [13, 14].”
• Energy Harvesting Sensor Nodes: Survey and Implications (2011, background): “2mW/cm2 environments[29] Unpredictable Induction Exhalation[24] Passive human power, 1W Breath masks 40% 0.”
• Micro Power Generator for Harvesting Low-Frequency and Nonperiodic Vibrations (2011, methodology): “This concept is known as frequency up-conversion, and it was developed at the University of Michigan by Kulah and Najafi [31], [32].”
• Toward Broadband Vibration-based Energy Harvesting (2010, methodology): “In the two-stage design, the low excitation frequency can be further amplified to the high natural frequency of the cantilever beam (Rastegar et al., 2006; Tieck et al., 2006; Lee et al., 2007; Kulah and Najafi, 2008; Wickenheiser and Garcia, 2010).”
• Investigation of a MEMS piezoelectric energy harvester system with a frequency-widened-bandwidth mechanism introduced by mechanical stoppers (2012, neutral): “In order to achieve a significant power level at a relatively lower frequency, the frequency up-conversion (FUC) approach has been proposed by Kulah and Najafi [18].”
• Electromagnetic energy harvesting from vibrations of multiple frequencies (2009, methodology): “For the traditional large mass-/coil-type electromagnetic harvester, the instantaneous output power at steady state can be expressed by equation (5) [13]”