A major concern of the power quality in distributed systems is related to the mitigation of voltage imbalances. This function can be implemented directly in the control system of the distributed generation power converters working simultaneously with the standard operation modes. This study presents a negative-sequence voltage elimination technique for distributed generators in grid-feeding operation mode. The proposal guarantees a complete elimination of the negative-sequence voltage, while operating without a priori in-depth knowledge of the grid configuration and its characteristics. The proposed control architecture is presented together with its pseudocode, a controller flowchart and a discussion of the implementation aspects. A closed-loop modelling is derived based on a complex transfer function approach, which is used to determine stability margins and control design guidelines. A laboratory setup was implemented to verify the performance of the proposed strategy.

中文翻译：

---

并网运行模式下分布式发电机的负序电压消除

分布式系统中电能质量的主要问题与缓解电压不平衡有关。此功能可以直接在与标准操作模式同时工作的分布式发电转换器的控制系统中实现。这项研究提出了一种在电网馈电运行模式下的分布式发电机负序电压消除技术。该建议可保证完全消除负序电压，而无需事先了解电网配置及其特性就可进行操作。提出了所提出的控制体系结构及其伪代码，控制器流程图以及对实现方面的讨论。基于复杂的传递函数方法得出闭环建模，用于确定稳定性裕度和控制设计准则。实施了实验室设置，以验证所提出策略的性能。