energy scavenging a look at nano-fibers and other piezoelectric devices for body area networks...
TRANSCRIPT
Energy Scavenging
A Look at Nano-fibers and Other Piezoelectric Devices for
Body Area Networks
Presented by Stuart Wooters
Outline
• Characteristics of Movement Scavenged Energy
• Nano-Fibers• PVDF• Potential Implementations• Design considerations
Characteristics:
• What are some of the requirements of movement generated energy?– Frequency Range– Types of Movement– Energy Potentials
Microfibre–nanowire hybrid structure for energy scavenging
Yong Qin1, Xudong Wang1 & Zhong Lin Wang1
Basic Concept
• Use vibrations and friction between two fibers to create an electric current.
• Textile fibers are dense and have the potential of accumulating a lot of energy.
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814.
Structure
• Fibers are coated in a Zinc Oxide growth.
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814.
Conceptual Analogue
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814.
IV Curve of Coated Strand
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814. (Supplement Figure 1)
IV Curve of Bent Strands
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814. (Supplement Figure 2)
Diode characteristics help insure same direction current for all nano-fibers
Short Circuit and Open Circuit Measurements at 80rmp
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814.
Range of Frequencies
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814. (Supplement Figure 6)
Six Fibers
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814. (Figure 4)
Viability Case 1 (Cylindrical Fibers)
P=4nA x 3mV / .2s = 60pW
Effective Power:19 mW per 1m2
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814. (Supplement)
Viability Case 2 (Square Fibers)
Yong Qin , Xudong Wang & Zhong Lin Wang "Microfibre-nanowire hybrid structure for energy scavenging", Nature, Volume 451, 14 February 2008 Page(s): 809 - 814. (Supplement)
P=4nA x 3mV / .2s = 60pW
Effective Power:76 mW per 1m2
Basic Equations
• Charge Density:D = Q/A = d3nXn
• Open Circuit VoltageV0 = g3nXnt
R H Brown “Energy Generation using Piezo Film” published by Measurment Specialties original publish year 1991
Energy Expectations
• Maximum Charge Density:– 7mC/m2
• Maximum Energy Expected:– 200 kJ/m3
R H Brown “Energy Generation using Piezo Film” published by Measurment Specialties original publish year 1991
PVDF (Polyvinylidene Fluoride)
• Generates energy through stress/strain
• Kinetic Energy to Electrical Energy– Dropping Ball test– Stepping test
R H Brown “Energy Generation using Piezo Film” published by Measurment Specialties original publish year 1991
Basic Measurements
R H Brown “Energy Generation using Piezo Film” published by Measurment Specialties original publish year 1991
Potential Implementations
• How can we incorporate these devices into our networks?
• Can they be more than good sensors?