【作者】 刘玉龙；

【导师】 徐岩； 殷启国；

【作者基本信息】 华北电力大学 ， 电气工程， 2011， 硕士

【摘要】 电网无功平衡是保证电力系统的电能质量、降低损耗、使电网经济、安全、可靠运行的重要部分。在电力系统中,用电设备多呈感性,且功率因数较低,从而导致电网中出现大量的无功功率,降低了供电质量。在乐亭县农村中压电网中,由于输电线路长、配电变压器多、负荷季节性和时变性较强,线路无功损耗更加明显,使得农网存在较大的降损空间。针对乐亭县农村中压配电网无功损失较为严重的现象,本文按照集中补偿与分散补偿相结合、高压补偿与低压补偿相结合、调压与降损相结合的原则,做了以下几方面的工作:(1)通过农网无功算法,对农网的无功进行数学分析,论述了通过在10KV线路安装电容无功补偿装置进行无功补偿的原理;(2)通过对乐亭县两条典型农网10kV配电线路的分析,得出了利用配变低压侧集中补偿+中压线路补偿这一补偿模式的补偿方案,由于该线路季节性变化较大应采用自动投切无功补偿装置,确定了应用户外高压无功自动补偿装置,通过数值计算分析确定了这一方案的节能效果。(3)通过分析变电站调容工作原理及特点,对变电站的调容方式进行了比较,结合马头营35kV变电站无功调容系统农网改造的实际应用,提出并实施了一种新型的适合农网特点的无功调容方式,对乐亭县农网35KV变电站的无功补偿系统进行改造。更多还原

【Abstract】 Reactive power balance is to ensure that the power system, power quality, reduce losses, the power system economic, safe and reliable operation of the important part. In the power system, electrical equipment mostly emotional, and low power factor, resulting in a large number of grid reactive power, reduce the quality of power supply. Leting County in the medium voltage power grid, because of long transmission lines, distribution transformers and more seasonal and time-varying load of strong reactive power loss is more obvious, so there is a big loss reduction and rural power grid space. Leting County for medium voltage distribution network reactive losses more serious phenomenon, this focus on compensation and dispersion compensation in accordance with the combination of high compensation and the combination of low compensation, voltage regulation and the principle of combining Loss Reduction, made the following aspects work:(1) According to the reactive power algorithm of the rural power network, reactive power of the rural power network is analyzed. This paper also discusses the principle of reactive power compensation, which is installing the capacitor reactive power compensation in 10kV line. (2) According to the analysis of two typical rural 10kV distribution lines in LeTing county, the compensation scheme is presented, which makes the low voltage side with concentrated compensation and adds the medium voltage circuit compensation. As the major seasonal variation in this line, larger auto-switching reactive power compensation devices should be applied. The energy saving effect of this scheme is determined on the basis of the numerical analysis. (3) According to the principle and characteristic of adjustable capacitors in the substation, the operating mode of adjustable capacitors is compared. Based on the practical application of rural reactive power compensation system with adjustable capacitors in 35kV Matouying substation, a new mode of reactive power compensation system with adjustable capacitors is put forward and used. The system of reactive power compensation system in rural 35kV LeTing substation is improved.更多还原