中文摘要：

针对城市轨道交通供电系统无功功率过补偿问题,建立集中、分散2种供电方式下的供电网络模型,基于节点电压法,给出用于轨道交通供电系统功率因数分析的简化算法,并分析2种供电方式下不同负载率、不同0.4 kV母线功率因数对整个供电系统功率因数的影响。计算分析表明：在集中供电方式下,由于电缆线路长、电压等级高、无功功率返送现象严重,并难以通过调整0.4 kV母线功率因数避免返送无功功率,因此需要在主变电所35 kV母线上并联无功功率补偿装置,以吸收电缆产生的容性无功功率;在10 kV分散供电方式下,因为电缆线路短、电压等级低,返送无功功率现象较轻,所以可通过调整0.4 kV母线功率因数解决无功功率返送问题。

英文摘要：

Aiming at the problem of over-compensation for the reactive power in the power supply system of urban mass transit, the models of power supply net were established under centralized and decentralized power supply modes. Based on the node voltage analysis method, the simplified algorithm for analyzing the power factor of the urban mass transit power system was proposed. The influence of the load rate and power factor of 0.4 kV buses on the system power factor was analyzed under two power supply modes. Calculation and analysis show that under centralized power supply mode, the over-compensation is more serious and can hardly be avoided by adjusting the power factor of 0.4 kV buses because of the long cable line and the high voltage. Consequently, it is necessary to install the parallel reactive power compensation devices on 35 kV buses of the main substation which can be used to absorb the reactive power of the cable. However, under 10 kV decentralized power supply mode, the over-compensation is unobvious owing to the short cable line and the low voltage. The problem can be solved by adjusting the power factor of 0.4 kV buses.