This work aims at finding pedestrian walking characteristics at U-type stairs according to the width change of stairs and appropriate spot for installing piezoelectric energy harvesting.The number of pedestrian at two...This work aims at finding pedestrian walking characteristics at U-type stairs according to the width change of stairs and appropriate spot for installing piezoelectric energy harvesting.The number of pedestrian at two kinds of stairs(one is stairs with 1.5 m in width and the other is stairs with 3 m in width) was estimated by calculating the number of steps on the stairs by a zone which is divided into 30 cm×30 cm.The result shows high density in the middle in the case of narrow stairs but traffic is concentrated on stair inside(pillar side) in stairs with large width.In conclusion,the location for installation of piezoelectric energy harvesting system should be considered differently on stairs width and the number of installation depends on total expected traffic and the expected traffic for a device.展开更多
After people or vehicles press, piezoelectric ceramics can send a weak and unstable alternating current. According to this characteristic, we made feet pressing energy collection and utilization device based on piezoe...After people or vehicles press, piezoelectric ceramics can send a weak and unstable alternating current. According to this characteristic, we made feet pressing energy collection and utilization device based on piezoelectric ceramics. The two parts of this device includes energy storage and utilization. In terms of storage, the energy collection module, can deposit AC sent by piezoelectric ceramics in the super capacitor after rectification. In terms of utilization of energy, the device achieve a variety of usage: through the USB interface, it can supply power for different equipments, replace the mobile station of train stations and realize the function of saving the electricity as the night corridor induction lamp, combined with vibration module design and programmable timer. The whole structure is supported by an acrylic plate, which saves cost and have good durability. This device implements the storage and usage of idle feet pressing energy. In conclusion, it is helpful to provide a new idea for people' s low carbon lives and has a quite broad application prospect.展开更多
The purpose of this study is to use magnetic field of 50/60 Hz up to 0.2 mT for energy source. This paper focuses on magnetic energy harvesting from electrical appliances which can be also used for power consumption m...The purpose of this study is to use magnetic field of 50/60 Hz up to 0.2 mT for energy source. This paper focuses on magnetic energy harvesting from electrical appliances which can be also used for power consumption monitoring. The magnetic energy harvesting device consists of an energy harvesting module, Cockcroft-Walton circuit and storage capacitor. First of all, typical magnetic fields around several electrical appliances are investigated. In order to harvest 10 mJ energy, the shape of magnetic flux concentration flange in energy harvesting module and number of steps in Cockcroft-Walton circuit are considered. From experimental results, magnetic energy harvesting of 17 mJ from a refrigerator is successfully demonstrated.展开更多
基金Project(NRF-2011-0000868)supported by the National Research Foundation of Korea(NRF)funded by the Korea government(MEST)Project(2011-0003968)supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)
文摘This work aims at finding pedestrian walking characteristics at U-type stairs according to the width change of stairs and appropriate spot for installing piezoelectric energy harvesting.The number of pedestrian at two kinds of stairs(one is stairs with 1.5 m in width and the other is stairs with 3 m in width) was estimated by calculating the number of steps on the stairs by a zone which is divided into 30 cm×30 cm.The result shows high density in the middle in the case of narrow stairs but traffic is concentrated on stair inside(pillar side) in stairs with large width.In conclusion,the location for installation of piezoelectric energy harvesting system should be considered differently on stairs width and the number of installation depends on total expected traffic and the expected traffic for a device.
文摘After people or vehicles press, piezoelectric ceramics can send a weak and unstable alternating current. According to this characteristic, we made feet pressing energy collection and utilization device based on piezoelectric ceramics. The two parts of this device includes energy storage and utilization. In terms of storage, the energy collection module, can deposit AC sent by piezoelectric ceramics in the super capacitor after rectification. In terms of utilization of energy, the device achieve a variety of usage: through the USB interface, it can supply power for different equipments, replace the mobile station of train stations and realize the function of saving the electricity as the night corridor induction lamp, combined with vibration module design and programmable timer. The whole structure is supported by an acrylic plate, which saves cost and have good durability. This device implements the storage and usage of idle feet pressing energy. In conclusion, it is helpful to provide a new idea for people' s low carbon lives and has a quite broad application prospect.
文摘The purpose of this study is to use magnetic field of 50/60 Hz up to 0.2 mT for energy source. This paper focuses on magnetic energy harvesting from electrical appliances which can be also used for power consumption monitoring. The magnetic energy harvesting device consists of an energy harvesting module, Cockcroft-Walton circuit and storage capacitor. First of all, typical magnetic fields around several electrical appliances are investigated. In order to harvest 10 mJ energy, the shape of magnetic flux concentration flange in energy harvesting module and number of steps in Cockcroft-Walton circuit are considered. From experimental results, magnetic energy harvesting of 17 mJ from a refrigerator is successfully demonstrated.