CAJ | 학술논문

光伏并网逆变器不平衡故障穿越过程中出现的过流问题严重影响系统运行的可靠性.为了解决该问题,首先分析传统故障穿越控制方案存在过流现象的机理,然后对过流问题进行了量化分析.在此基础上提出不平衡故障穿越限流控制方案,在实现有功和无功功率灵活调节的同时,有效地解决了故障穿越过程中并网逆变器过流问题,提高了系统运行可靠性.最后对传统方案和文中提出的方案进行仿真和实验研究,结果验证了提出方法的可行性和有效性.
광복병망역변기불평형고장천월과정중출현적과류문제엄중영향계통운행적가고성.위료해결해문제,수선분석전통고장천월공제방안존재과류현상적궤리,연후대과류문제진행료양화분석.재차기출상제출불평형고장천월한류공제방안,재실현유공화무공공솔령활조절적동시,유효지해결료고장천월과정중병망역변기과류문제,제고료계통운행가고성.최후대전통방안화문중제출적방안진행방진화실험연구,결과험증료제출방법적가행성화유효성.
The photovoltaic (PV) grid-connected inverter experiences the excessive current stress in case of the unbalanced fault ride through, which significantly affects the operation reliability of the system. In order to solve the problem, the inherent mechanism of the excessive current phenomenon with the conventional fault ride through control is discussed. The quantitative analysis of the current peak value is conducted. And then, a new current-limited control strategy is proposed. It achieves the flexible power control and successful fault ride through in a safe current operation area, which is beneficial to the system reliability. Finally, the simulation and experimental tests of the conventional and proposed control solutions are carried out. The results verify the effectiveness of the proposed method.