Research On Triboelectric Nanogenerator For Ship Vibration Energy Harvesting

With the advent of big data and the Internet of Things era,building intelligent ships has become an inevitable trend.An all-round and real-time dynamic monitoring which if necessary gives early warning of the ship,is significant for the construction and implementation of intelligent ships.That is,thousands of sensors,such as temperature sensors,humidity sensors and vibration sensors are required to monitor the ship's operation status and working environmental conditions.However,installation problems due to the complexity and specificity of the hull structure and environmental problems that may be caused by the limited service life of the batteries limit the installation and application of these sensors.During the voyage of a ship,a large amount of mechanical energy such as vibration energy is wasted,which can theoretically be converted into electrical energy and power sensors on board ship.Therefore,converting waste vibration energy on ship into electric energy and supplying power to these sensors may be an effective solution to the problem of sensors power supply.Since the invention of triboelectric nanogenerator(TENG)by Dr.Wang in 2012,based on the theory of Maxwell's displacement current,it can convert mechanical energy in the environment into electric energy by utilizing the coupling effect of triboelectrification and electrostatic induction,which is used to drive microelectronic devices and has been widely used in many fields,such as,physics,chemistry,biomedicine and electronics.It was verified that the TENG turned out to possess advantages such as high conversion efficiency,low cost,flexibility,and diverse choices of materials,which is beneficial to energy harvesting and signal monitoring.Based on the principle of contact freestanding triboelectric nanogenerator,this paper proposed a honeycomb inspired structure triboelectric nanogenerator(HSI-TENG)with flexible electrode substrate for ship vibration energy harvesting and ship vibration monitoring.It establishes the relationship of V-Q-x by studying the working principle of the HSI-TENG,investigates the factors that may influent the output performance of the HSI-TENG and completes adaptability tests on board.The main research contents and conclusions are as follows:Firstly,this paper designed and optimized a honeycomb inspired structure triboelectric nanogenerator based on the theoretical and experimental analysis.Then,related experiments are accomplished and confirmed that the HSI-TENG shows non-resonant characteristics,which demonstrated its wideband frequency vibration energy harvesting.Secondly,this paper discusses some correlative factors that may affecting the output performance of the HSI-TENG,such as vibration direction,vibration frequency,amplitude,acceleration and electrode distance.The results show that the vibration direction and electrode distances have little effect on the output performance.Well,the output performance is rapidly increased to a stable region when the acceleration and amplitude exceed a certain value,which is designed as the critical energy boundary and indicates the output initial state of the HSI-TENG.Thirdly,this paper verifies that the HSI-TENG can convert mechanical vibration energy into electric energy,directly illuminating nearly 230 LED,or powering a sensor by a corresponding electric management module.An average open-circuit voltage peaks of 110 V is generated under the experimental conditions of amplitude 2 mm and frequency 25 Hz.The maximum power can reach 2.5 mW and the power density is 50 W/m3 under an external resistance of 300 M?.In addition,researches on stability and durability of the HSI-TENG have been carried out through a long-term testing.Finally,compared to the commercial sensor,this paper confirmed the truth of the consistency between the output electrical signals of the HSI-TENG and the input of the vibration exciter.Then,in order to ensure the practicality of the designed HSI-TENG,this work put it on the diesel generator of the "Yukun" of Dalian Maritime University,achieving a satisfactory response.Under the normal working condition of the diesel generator,it successfully performed vibration energy harvesting and signals monitoring functions,with the output open circuit voltage and the short circuit current are up to 70 V and 1.7 ?A,respectively,and the analyzed vibration frequency is same to the diesel generator vibration frequency of 33 Hz.Accordingly,it strongly supports its conclusions that the designed object in this paper can not only can be used for vibration energy harvesting,but also be used for vibration monitoring as self-powered sensors so that it can give early warning if there is any abnormal state when the machine is working.