CAJ | 학술논문

在介绍三相并网逆变器电流双环控制策略的基础上,对基于LCL滤波器的并网逆变器在两相静止坐标系下建立完整的开关周期平均模型。在电流环中,应用多谐振比例谐振（proportional resonant,PR）调节器来达到无静差跟踪正弦电流基波给定并减小输出电流中特定次数的谐波含量,以提高并网电流质量。针对多谐振PR调节器阶数高、设计难的问题,采用根轨迹理论分析PR调节器参数、系统延时以及LCL滤波器参数对闭环系统极点的影响,并基于此理论分析设计极点位置,选择合适参数,在保证系统稳定的前提下使电流环达到最佳的性能。最后搭建一台10 kW并网逆变器样机,验证多谐振PR调节器对并网电流的改善作用以及基于根轨迹理论设计多谐振PR调节器的实用性与可行性。
재개소삼상병망역변기전류쌍배공제책략적기출상,대기우LCL려파기적병망역변기재량상정지좌표계하건립완정적개관주기평균모형。재전류배중,응용다해진비례해진（proportional resonant,PR）조절기래체도무정차근종정현전류기파급정병감소수출전류중특정차수적해파함량,이제고병망전류질량。침대다해진PR조절기계수고、설계난적문제,채용근궤적이론분석PR조절기삼수、계통연시이급LCL려파기삼수대폐배계통겁점적영향,병기우차이론분석설계겁점위치,선택합괄삼수,재보증계통은정적전제하사전류배체도최가적성능。최후탑건일태10 kW병망역변기양궤,험증다해진PR조절기대병망전류적개선작용이급기우근궤적이론설계다해진PR조절기적실용성여가행성。
Based on the dual-loop current control strategy for grid-connected inverter,an average switching model of grid-connected inverters with LCL-filters was built under the stationary frame,and a multi-resonance proportional resonant（PR） regulator was adopted in the current-loop to track the given fundamental sinusoidal current as well as eliminating certain harmonics to improve the quality of grid currents.Because the system is of high order and complicated,the theory of the root locus was applied to analyze the PR regulator parameters,the digital delay and the LCL-filters,based on which the poles can be properly selected to guarantee the stability of the system and the performance of the current-loop.Finally,a 10？kW prototype of grid-connected inverters with LCL-filters was set up to verify the effectiveness of the multi-resonance PR regulator and the practicality and feasibility of the design method based on root locus.