CAJ | 학술논문

　　光伏发电系统并网点处的谐波电压由系统扰动、本地负荷和光伏发电系统共同确定，基于波动量法提出一种以并网点谐波电压波动量为特征的光伏发电系统孤岛检测方法。测量公共联结点谐波电压，用小波变换法提取测量电压中包含的高次谐波分量，以高次谐波电压波动量变化规律作为孤岛识别和检测指标，无需外加扰动，可消除检测盲区。基于 IEEE.Std 1547标准，对理想光伏发电并网系统进行的仿真证明，利用并网点测量电压中包含的谐波电压波动量进行孤岛检测，当测量点处的电压和频率在正常范围内时，不仅可快速、准确地检测孤岛，还能准确识别电网故障引起的电压暂降、投切负荷等干扰，避免伪孤岛引起的检测错误。
　　광복발전계통병망점처적해파전압유계통우동、본지부하화광복발전계통공동학정，기우파동량법제출일충이병망점해파전압파동량위특정적광복발전계통고도검측방법。측량공공련결점해파전압，용소파변환법제취측량전압중포함적고차해파분량，이고차해파전압파동량변화규률작위고도식별화검측지표，무수외가우동，가소제검측맹구。기우 IEEE.Std 1547표준，대이상광복발전병망계통진행적방진증명，이용병망점측량전압중포함적해파전압파동량진행고도검측，당측량점처적전압화빈솔재정상범위내시，불부가쾌속、준학지검측고도，환능준학식별전망고장인기적전압잠강、투절부하등간우，피면위고도인기적검측착오。
In the photovoltaic power generation system, the harmonic voltage of the point of common coupling (PCC) is determined by system disturbance, local load and photovoltaic power generation system itself together. Based on the fluctuations of this harmonic voltage, a new islanding detection method for the PV system is proposed. By extracting the higher harmonic components from the wavelet transformation of point of common coupling (PCC) voltage, and then taking its fluctuations as the islanding identification and detection index, non-detection zone (NDZ) can be eliminated, without a plus disturbance. According to IEEE Std.1547, simulated verification of the proposed method is accomplished in the ideal photovoltaic grid system. When the PCC voltage and frequency are within the normal range, it can not only give a fast and accurate detection to the occurrence of islanding, but also identify the false islanding, such as voltage dips and switching loads, effectively avoiding false detection caused by the false islanding.