【摘要】 大量分布式电源并网,使得配电网电压越限和稳定性问题更加突出,而配电网微型同步相量测量装置(distribution phasor measurement unit,D-PMU)为配电网电压特性在线监测提供了新手段。本文提出了一种适合于D-PMU的、综合反映配网电压稳定性和越限的电压质量在线评估指标。首先,在分析支路在线电压稳定指标配电网适应性的基础上,说明了现有指标能反映一定程度的配电网电压稳定性,但对于常见的电压越界问题很难反映;其次,结合构造的连续性阶跃模拟函数模拟电压越界,提出一种综合反映配电网电压稳定性和越限的电压质量在线评估指标,该指标可由DPMU的量测信息快速计算获得,能很好地反映出配电网中常见的电压越界问题,适用于配电网电压安全和稳定的在线监测与评估;最后,分别以简单四节点配电系统和实际20 kV配电网模型为算例,进行仿真验证。结果表明,所提指标能较好地及时反映配电网的电压越限与稳定性,验证了指标的正确性与有效性。更多还原

【Abstract】 With the large number of distributed power sources connected to the grid,the voltage over-limit and stability problems of the distribution network are more serious,and the emergence of distribution network phasor measurement unit( D-PMU) provides a new means for real-time online monitoring of the stable operation of the distribution network. This paper proposes an online evaluation index for voltage quality that is suitable for D-PMU and comprehensively reflects the voltage stability and over-limit of the distribution network. Firstly,on the basis of analyzing the adaptability of the on-line voltage stability index in distribution network,it show s that the existing indexs can reflect the voltage stability of the distribution network to a certain extent,but it is difficult to reflect the common voltage out of bounds problem. Secondly,through constructing a continuous step simulation function to simulate the voltage out of bounds,an online evaluation index is proposed. The index can be quickly calculated by the measurement information of the D-PMU,which can well reflect the common voltage over-limit problem in the distribution network. Finally,the simulation is verified by a simple four-node power distribution system and an actual 20 kV distribution network model. The results show that the proposed index can reflect the voltage limit and stability of the distribution network timely,and verify the correctness and effectiveness of the index.更多还原