| Energy is the cornerstone,which is the existence and development of modern society.With the rapid development of the global economy,energy consumption,followed by the global issue consisting of the environmental pollution and scarcity of traditional energy,has grown constantly,especially a series of severe problems caused by the fossil fuels abuse.Great changes has been appeared consequently,particularly the hazy weather which has damaged the daily commute and the physical health.Fortunately,the emergence of new energy is optimizing the environment,and relieving the environmental pressure.For example,the distributed photovoltaic power generation has been favored by people,due to its abundant resources and no geographical restrictions.First,this study states the background and the significance of collaborative control,deeply analyzing the research progress at home and broad,meanwhile it elaborating the composition of distributed photovoltaic power generation system,and the its advantages of the type and structure of the system.Second,a battery for charging and discharging controller is designed.This designing scheme mainly consisting of two aspects--hardware and software.The hardware part is divided into primary and secondary circuits,and the former includes the converter’s schematic diagram in detailed and its principle of operation,as well as the selection calculation of various devices.The latter focuses on the sampling loop and the protection drive circuit;The software mainly includes the control strategy and the software flow chart,studies the double closed-loop control strategy and the staggered control thought,gives the software flow chart.Boost-Buck bidirectional converter was built on the basis of the design we have just worked through,and its stability is verified.Third,a study explains the work pattern and corresponding control strategy in each unit of the distributed photovoltaic power generation system,analyzes the objectives to be achieved by the cooperative control,and illustrates the advantage of the collaborative control of the system application.For the stability and low efficiency of distributed photovoltaic power generation systems,a cooperative control strategy is proposed,which includes the stable operation of the system and rational use of energy under the circumstance of the off-grid and grid-connected mode,as well as,the Status inheritance method of switching to each other between the two modes for ensuring fluent switching.Finally,a set of 1.5kW distributed photovoltaic power generation experimental system is set up,and,for the above-mentioned control strategy,a large number of experimental verificationsis carried out.Under the off-grid and grid-connected mode,the full-power experiment is satisfactorily completed.The photovoltaic cell is photovoltaic system input terminal,on the contrary the output is an inverter.Therefore,the stability of two aspects is verified by some studies--the experiment about the power change of input side photovoltaic cell was affected by the light intensity,and research of the output side of the inverter is affected by the load switching.All the photovoltaic power generation systems can work smoothly.The cooperative control strategy,proposed for the current-shock problem of the switching of the two modes above,has been studied experimentally,thus verifies the validity of status inheritance. |
