Research On Solar Battery Array Simulator Based On DSP

Solar energy attracts more and more attention as a new-style renewable resource.And photovoltaic technology contains the highest technical content and is a mostprospective technology among solar energy utilization technology. In the process ofdevelopment of photovoltaic power generation system, the experimental environment ofphotovoltaic power generation will be influenced by sunlight intensity and ambienttemperature, which causes high experiment cost and long development cycle. Researchon solar battery array simulator can greatly shorten the development cycle ofphotovoltaic power generation system, increase development efficiency andcreditability of research results.Detailed establishment process of solar battery model has been provided in thispaper, and with the help of MATLAB simulation tool the simulation results haveverified the correctness of the model, which provides basis for simulator development.In the part of hardware design, this paper has designed the hardware system, whoseoutput power can reach300W, consisting of three modules: BUCK circuit as maincircuit topology, control circuit based on TMS320LF2407and detection circuit. Thispaper adopts the digital control system which greatly simplifies the system’s hardwarecircuit. Overall control of the simulator’s working process can be realized by runningprograms to process the system’s digital signal.As to the control strategy, six broken line model is used to fit the I-V characteristiccurve of the solar battery. On this basis, this paper uses numerical method to determinethe load working point. In this system, double closed-loop control is applied and currentand voltage signal are the command control signal of the inner loop and the outer looprespectively.Due to the limit of time, debugging is not carried out and simulation results of theexperiment are given in this paper. Using MATLAB simulation tool, six broken linemodel and four broken model are simulated respectively. It can be seen from thesimulation results that six broken line better suits the solar battery simulator in thispaper. Each operating point of the six broken line model agrees well with output I-V characteristic of solar battery which needs to be simulated and the model has a gooddynamic property. In addition, the system can choose the power of the simulativephotovoltaic array as needed.Therefore, the system proposed in this paper can well meet the requirement of thephotovoltaic power generation system for experimental conditions, make thephotovoltaic power generation experiment be immune to the weather, the radiationintensity and other factors to some extent, reduce experimenter’s work loads, saveexperimental time and cut experimental cost.