Design And Development Of The Power Electronic Load For20kW Tidal Current Energy Generator Sets

With the rapid development of society, people’s demand for energy has beenincreased all the time. With a large number of traditional fossil fuels being consumed,its reserves are dwindling and the extensive use of traditional fossil fuels has alsocaused further environmental pollution. In order to reduce damage to the environmentand get a long-term stable supply of energy, the development of new energy is a keyto solving these problems. The world’s major powers of energy are improving theirenergy structure positively by developing and utilizing a variety of green renewableenergy. Tidal current energy has significant features a strong regularity andabundant in its reserves, it has been paid more and more attentions by every countryof the world. In this paper, tidal current energy has been explored and accessedthrough the design of power electronic load.In this thesis, the role of power electronic load in20kW tidal current energypower generation system is described and the overall structure of the powerelectronics load system is determined. Starting from the main circuit of the powerelectronic load, the main circuit topology and the idea of segmented load control iselaborated and devices used in this system is determined by formula calculation,parameter comparison and system requirement.The principle of PWM control of power electronic switches is discussed in thisthesis and the control algorithm is designed. The power electronic load described inthis thesis possesses constant power control, constant current control, constant voltagecontrol and constant resistance control in control functions. In the design phase ofpower electronic load, the main circuit and the control algorithm is simulated andverified by constructing Matlab/Simulink simulation model.In the aspect of software design, the conversion procedures between variousworking conditions in the tidal current energy power generation system are firstlyconfirmed. According to the requirement of power generation system, constant powercontrol scheme which meets the control needs is designed. Then with the help of alocal touch-screen software design, the operation situation of underwater generator setand onshore power electronic load can be visually observed on the spot. Design ofremote GPRS communication makes it feasible for us to observe the operationsituation of devices on the spot.Higher requirements for stability of the tidal current energy power generationsystem have been put forward. How to design a more comprehensive testing schemeto verify the stability of tidal current energy power generation system has also been aresearch direction of this thesis. Loading experiment and water leakage experimenthave been designed so as to test the overall stability of the system and lay a solidfoundation for subsequent experiments at sea.