CAJ | 학술논문

当电网出现故障时，在孤岛检测时，常用的无源检测方法和有源检测方法中的有源频率偏移、滑模频率偏移和输出功率扰动法都存在检测盲区。针对这几种方法在孤岛检测时的缺陷，提出了一种主动式孤岛检测新方法，通过脉动负载改变逆变器并网负荷大小，检测逆变器输出电压、频率等来判断孤岛的发生。通过理论分析了该方法具有检测速度快，对电网无影响，无检测盲区。该方法对多台并网运行的光伏逆变器也同样适用。并通过仿真测试和实际产品试验验证了该方法的有效性。
당전망출현고장시，재고도검측시，상용적무원검측방법화유원검측방법중적유원빈솔편이、활모빈솔편이화수출공솔우동법도존재검측맹구。침대저궤충방법재고도검측시적결함，제출료일충주동식고도검측신방법，통과맥동부재개변역변기병망부하대소，검측역변기수출전압、빈솔등래판단고도적발생。통과이론분석료해방법구유검측속도쾌，대전망무영향，무검측맹구。해방법대다태병망운행적광복역변기야동양괄용。병통과방진측시화실제산품시험험증료해방법적유효성。
When the grid fails, two methods are used for the islanding detection, one is the passive detection method and the other one is the active detection method which includes the active frequency drift, sliding mode frequency shift and output power disturbance method, but they all have non-detection zone. For the defects of these methods, this paper puts forward a new active islanding detection method. It identifies the islands through changing the size of the inverter output load with pulsating load, and detecting inverter output voltage and frequency. The theoretical analysis shows that this method is fast and has no effect on the grid, and there are not blind spots. This method also applies to multiple grid-connected PV inverters. Simulation results verify the validity of the method.