With the proliferation of microgrids (MGs) into the utility grid (UG), MGs with multiple distributed generations (DGs) face challenge to flexibly support voltage during UG faults. In this paper, a multi-stage voltage support optimization method is proposed to stabilize voltage, current and power, for safeguarding the MG operation and providing flexible power delivery capacity. The proposed method consists of three stages: 1) voltage stage in which the phase voltage instead of the sequence voltage regulation is considered to support voltage more precise; 2) current stage in which a novel current generation strategy with maximum current limiting (MCL) is formulated by directly embedding network impedance features; 3) power stage in which multiple matching scenarios for max/min active/reactive powers are developed to improve the flexibility of power delivery capacity. Several test cases are presented and pertinent results are discussed to validate the effectiveness of the proposed method for voltage support of MG with multiple DGs.

中文翻译：

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具有多个分布式发电单元的微电网的多阶段电压支持优化

随着微电网（MG）向公用电网（UG）的扩散，具有多个分布式发电（DG）的MG面临在UG故障期间灵活地支持电压的挑战。本文提出了一种多级电压支持优化方法，以稳定电压，电流和功率，以维护MG的运行并提供灵活的功率传输能力。所提出的方法包括三个阶段：1）电压阶段，其中相电压而不是顺序电压调节被认为可以更精确地支持电压；2）当前阶段，其中通过直接嵌入网络阻抗特征来制定具有最大电流限制（MCL）的新型电流生成策略；3）功率级，其中针对最大/最小有功/无功功率开发了多种匹配方案，以提高功率传输能力的灵活性。提出了几个测试案例，并讨论了相关结果，以验证所提出方法对具有多个DG的MG的电压支持的有效性。