Based The APSO Algorithm In The DSP Applications In Photovoltaic Maximum Power Point Tracking

With the situation of energy resource crisis and the problem of circumstancepollution become more and more severity, exploitation and utilization of the green solarenergy resource is imperative. And the most widely used is the use of Photovoltaic (PV).However, partially shaded and illumination inequality conditions are common in the useof PV systems. The resulting mismatch phenomenon of the array not only affects thepower genetated by solar system leading to security and reliability problem, but alsomakes the regular maximum power point tracking (MPPT) algorithm very difficult toaccomplish in this case. So it greatly reduces the conversion efficiency of PV system.Under this background, the dissertation deeply researches the characteristic curves of PVarray operating under complicated conditions, APSO algorithm is applied to thephotovoltaic maximum power point tracking. Designs and implements a novel MPPTalgorithm in order to compensate the defects of traditional MPPT. So the research of thenovel MPPT algorithm has the important realistic and practical engineering applicationmeaning.Firstly, in this paper include the research status of the MPPT control algorithm, adetailed theoretical analysis of the binding process of the PSO algorithm photovoltaicmaximum power point tracking, and elaborated APSO algorithm implemented on theDSP. Therefore this paper conducts an artificial shading experiment on PV arraysoperating under complex conditions. By observing the large number of experimental data,8important laws can be found and they are the foundation of the realization of the novelMPPT algorithm. Secondly, according to system design requirements this paper gives theoverall system design scheme and introduces the design solutions of hardware andsoftware in detail. Thirdly, the hardware circuit can be built according to the hardwaredesign scheme. DSP TMS320F28027of TI incorporated is used as the main controller. Itsinput signals are the voltage, current sampling signal from the sampling circuit and thesignal processing circuit. The main controller outputs the PWM pulse wave which runsthrough the isolating circuit, driving circuit to control the power tube on and off in theDC/DC circuit. Constant changing duty cycle of PWM wave dynamically adjustsequivalent load impedance of PV arrays in order to achieve the purpose of tracking themaximum power point. Fourthly, the novel MPPT algorithm is programmed based on CCS development environment. It mainly consists of main program, AD samplingprocedures, improved perturbation&observation subroutine, global peak point trackingsubroutine and timer interrupt subroutine. Finally, it tests each module and the novelMPPT algorithm respectively and gives the necessary test resulting graphs.The test results show that hardware and software algorithm conform fully to thedesign requirements and the APSO MPPT algorithm can more quickly track the globalmaximum power point than traditional algorithms. Therefore it has the great technologyreference value to the deeper research on MPPT control algorithm of PV system in thefuture.