一种改进的主动移频式孤岛检测技术  

An improved anti-islanding detection technology of active frequency shift

作　　者：蔡逢煌[1,2] 王武[1,2] 陈四雄 洪巧文[1] 

机构地区：[1]福州大学电气工程与自动化学院,福建福州350116 [2]漳州科华技术有限责任公司博士后工作站,福建漳州363000

出　　处：《电力系统保护与控制》2013年第24期70-75,共6页Power System Protection and Control

基　　金：2012年国家重大科技成果转化专项项目;福建省自然科学基金项目(2012J01257;2013J01178)

摘　　要：为了提高孤岛检测速率,改善并网电流波形质量,在传统AFD扰动方式基础上提出了一种新的改进型电流扰动策略。对传统AFD而言,截断系数cf越大则电流畸变率越大,而cf较小则检测效率降低。因此,如何在孤岛检测效率与电流畸变之间取得良好平衡是孤岛检测问题中的难点。所提出的电流扰动法对并网电流施以变步长cf扰动,能有效改善稳定电流波形THD,同时在负半波加强扰动量能提高检测速率。理论分析与仿真试验均验证了该新型扰动策略的正确性和可靠性。To improve the efficiency of island detection and the quality of current waveform, a new current disturbance strategy is proposed based on the traditional AFD. As to the traditional AFD, the rising of chopping fraction （cf） leads to more current distortion and the smaller cf resulted in low efficiency of island detection. Therefore, it＇s difficult to achieve good balance between the efficiency of island detection and current distortion in anti-islanding detection. Now the proposed current perturbation method can effectively improve the THD of stable current by applying variable step disturbance on grid current. And the new method also improves the rate of detection by strengthening disturbance in negative half wave. Theoretical analysis and simulation experiment prove the validity and reliability of the strategy.

关 键 词：分布式发电 孤岛检测 主动移频 电流畸变 截断系数 

分 类 号：TM76[电气工程—电力系统及自动化]