电网功率因数的提高方法和意义

Measures and Significances of Improving the Power Factor in Power System

文中简要分析了影响配电网功率因数的主要因素,指出了电力变压器和异步电动机是消耗无功功率的主要设备,给出了供电电压超出规定范围对功率因数造成的影响。并对并联电容无功补偿进行了详细分析,得出了补偿电容容量的计算方法,推导了提高功率因数和降低网损之间的关系。同时,对提高系统自然功率因数的方法进行了阐述,给出了合理使用电器设备、提高异步电动机的检修质量、采用同步电动机或异步电动机同步运行提高功率因数和合理改善配变的运行方式等4种提高系统自然功率因数的方法。最后,概述了提高功率因数所带来的经济效益和社会效益。

By brief analysis of the main factors that impact the power factor of distribution grid, it can tell that power transformers and asynchronous motors are important equipments consuming reactive power, it also points out the impact on power factor when supplying voltage exceeds the prescribed limit. This paper detailedly analyzed reactive-compensation by parallel connected capacitor, got the calculating method of compensating capacitor capability, and deduced the relation between improving power factor and reducing power loss. Meanwhile, the methods that enhance the natural power factor of the system were discussed, and four methods were given, that is, applying electrical equipments reasonably, improving maintenance quality of asynchronous motors, employing synchronous operation of synchronous or asynchronous motors to increase power factor and choosing the capacity of distribution transformers in reason, advancing operating modes of distribution transformers. Finally, the economic and social benefits by improving the power factor were outlined.