CAJ | 학술논문

针对光伏系统最大功率点跟踪技术的研究和应用现状，提出一种梯度式变步长扰动观察法。该方法基于梯度寻优思想，在扰动过程中按照 P-U 特性曲线的斜率可自动改变扰动步长，进而提高系统寻优效率。但由于扰动观察法自身存在缺陷，在外部条件出现剧烈变化时，可能存在误判问题并最终导致故障。为解决该问题，在梯度式变步长扰动观察法基础上引入功率预测算法。基于该扰动观察法的控制策略，利用 Matlab/Simulink 对光伏系统的静、动态特性进行仿真，验证该方法的可行性。并在10 kW 样机上进行实验研究，结果表明该方法具有很好的动、稳态性能，能有效地消除误判，实现最大功率点跟踪。
침대광복계통최대공솔점근종기술적연구화응용현상，제출일충제도식변보장우동관찰법。해방법기우제도심우사상，재우동과정중안조 P-U 특성곡선적사솔가자동개변우동보장，진이제고계통심우효솔。단유우우동관찰법자신존재결함，재외부조건출현극렬변화시，가능존재오판문제병최종도치고장。위해결해문제，재제도식변보장우동관찰법기출상인입공솔예측산법。기우해우동관찰법적공제책략，이용 Matlab/Simulink 대광복계통적정、동태특성진행방진，험증해방법적가행성。병재10 kW 양궤상진행실험연구，결과표명해방법구유흔호적동、은태성능，능유효지소제오판，실현최대공솔점근종。
ABSTRACT:According to the research and application status of maximum power point tracking (MPPT) algorithm in photovoltaic systems, this paper proposed a gradient variable step size perturbation and observation (P&O) method which based on gradient optimizing ideology. In the optimizing process, the step size can be changed automatically with the slope of P-U characteristic curve, thereby increasing optimizing efficiency. But due to the shortcoming of P&O method, there may be a misjudgment when external conditions change sharply and then cause fault. In order to solve the problem, the power prediction algorithm was put forward based on the proposed method. The simulation of Matlab/Simulink about the photovoltaic system, and the research on the 10 kW prototypes were made based on the strategy. The results show that the method has good dynamic performance and steady state performance, and can eliminate the miscarriage of justice effectively to achieve maximum power point tracking.