220kV及以下电网感性无功补偿容量初探

Preliminary Study on the Inductive Reactive Compensation Capacity for Power Grids in 220 kV and Lower Voltage Grades

大规模使用电缆以及电网建设超前于负荷水平,可能导致220kV及以下电网感性无功容量不足。文章提出以"发电厂平均功率因数"为指标,来评价220kV及以下电网不同运行方式下感性无功容量是否充裕:该指标数值在0.95(迟相)～0.98(迟相)时,表明系统无功平衡情况较好;当该值在0.98(迟相)以上甚至进相时,表明系统感性无功容量不足。使用该指标对云南滇西电网2010年的无功电压情况进行了计算分析,对该地区2010年负荷在原预计水平以及降低40%情况下的无功补偿方案提出了建议。

The large-scale utilization of cables and the construction of the grid ahead of the load level may lead to insufficient inductive reactive capacity of the grid in 220kV and lower voltage grades. In this paper, an index named “average power factor of the power plants” is proposed to evaluate inductive reactive capacity adequacy of the grid in 220kV and below under different operation modes： the value of the index between 0.95（lagging power factor） and 0.98（lagging power factor） demonstrates a preferable state of the reactive power balance, while the value larger than 0.98（lagging power factor） or even the “average power factor of power plants” in lead means the existence of an inductive reactive capacity gap. By use of this index, the reactive power and voltage condition of West Yunnan Power Grid in the year 2010 are calculated and analyzed, and some suggestions of the reactive power compensation scheme for this region in the year 2010 are proposed under normal and 40% reduced load level.