CAJ | 학술논문

通过对单相并网逆变器输出侧电流谐波的分析表明，在逆变器输出侧的电流谐波主要集中在开关频率和开关频率的整数倍处，其中开关频率处的谐波含量最大。为了更大程度地对开关频率处的谐波进行抑制而选择LLCL滤波器。由于系统谐振尖峰的存在，考虑成本低和简单的特点，所以选择无源阻尼法来抑制系统谐振尖峰。为了减小阻尼损耗而选择了电感和电阻并联方式。根据LCL滤波器能够在大于2倍开关频率区间表现的良好滤波能力以及LLCL滤波器在开关频率处能够更大程度地抑制电流谐波的特征，将二者结合产生了复合型LLCL滤波器。最后用仿真和试验证明：复合型LLCL滤波器在滤波效果以及阻尼损耗方面表现出的相对优越性。
통과대단상병망역변기수출측전류해파적분석표명，재역변기수출측적전류해파주요집중재개관빈솔화개관빈솔적정수배처，기중개관빈솔처적해파함량최대。위료경대정도지대개관빈솔처적해파진행억제이선택LLCL려파기。유우계통해진첨봉적존재，고필성본저화간단적특점，소이선택무원조니법래억제계통해진첨봉。위료감소조니손모이선택료전감화전조병련방식。근거LCL려파기능구재대우2배개관빈솔구간표현적량호려파능력이급LLCL려파기재개관빈솔처능구경대정도지억제전류해파적특정，장이자결합산생료복합형LLCL려파기。최후용방진화시험증명：복합형LLCL려파기재려파효과이급조니손모방면표현출적상대우월성。
Based on harmonic analysis of the output current of a single-phase grid-connected inverter, the output current harmonics mainly concentrate at the switching frequency and its integer multiple harmonics. And the harmonics at switching frequency is the most. To damp the harmonics at switching frequency greatly, LLCL filter was chosen. Due to the resonance peak, considering the low cost and simplicity, passive damping methods were selected to suppress the resonance peak. In order to reduce the losses on the damping components, an inductor and a resistor in parallel were adopted. According to the good filtering performance above twice the switch frequency of LCL filters and the better filtering characteristics of current harmonics at the switching frequency of an LLCL filter, a composite LLCL filter was investigated. Simulations and experimental results proved that the composite LLCL filter had better filtering effect and less damping losses by combining the two types of filters.