CAJ | 학술논문

直流微电网带动单相交流逆变负载时，直流电压会产生2倍频的周期波动，进而造成联网的光伏发电系统输出功率产生周期波动，无法持续处于最大功率输出点，从而间接降低了其发电效率。为解决上述问题，在分析直流电压周期扰动时的光伏发电系统输出功率特性的基础上，提出了光伏发电系统输出电流的比例-积分-谐振控制策略，比例-积分调节器用于电流的稳态无静差控制，而谐振控制器用于抑制周期扰动。详细分析了所提出方法的稳态误差、稳定性，各控制参数变化对电流控制性能以及直流电压波动抑制效果的影响，给出了各参数选取原则。仿真和实验结果验证了理论分析结果与所提出方法的正确性和可行性。
직류미전망대동단상교류역변부재시，직류전압회산생2배빈적주기파동，진이조성련망적광복발전계통수출공솔산생주기파동，무법지속처우최대공솔수출점，종이간접강저료기발전효솔。위해결상술문제，재분석직류전압주기우동시적광복발전계통수출공솔특성적기출상，제출료광복발전계통수출전류적비례-적분-해진공제책략，비례-적분조절기용우전류적은태무정차공제，이해진공제기용우억제주기우동。상세분석료소제출방법적은태오차、은정성，각공제삼수변화대전류공제성능이급직류전압파동억제효과적영향，급출료각삼수선취원칙。방진화실험결과험증료이론분석결과여소제출방법적정학성화가행성。
When DC microgrid supplies single-phase AC inverters, the ripple with two-fold AC frequency will appear in the voltage of DC-link bus, it leads to periodic fluctuation in the output of grid-connected photovoltaic (PV) generation system and solar cells cannot operate continuously at its maximum power point, thus the generation efficiency of PV generation system is decreased indirectly. In allusion to it, on the basis of analyzing output characteristics of PV generation system under DC-link voltage with periodic perturbation, a proportional-integral-resonant (PIR) control strategy for output current of PV generation system is proposed. The proportional- integral controller is used for static control under steady state and the resonant controller for suppressing periodic perturbation. The steady state error, stability of the proposed method as well as the impact of control parameter variation on current control performance and the effect of suppressing DC voltage fluctuation are analyzed in depth, and in the further, the principle of selecting parameters is given. The correctness and feasibility of the proposed method as well as results of theoretical analysis are verified by results of both simulation and experiments.