小电源在110kV变电站上网的一种实用保护解决方案

A practical protection scheme for small power source connected to power networks in 110 kV transformer substation

为了解决小电源上网给电网带来的诸多问题,如小电源侧保护灵敏度低甚至有时无法启动、小电源上网后变电站的供电可靠性降低等,该文提出了基于低电压保护的小电源上网的一种实用保护解决方案。该方案保护原理和配置简单,大大简化了保护整定和运行管理的难度,尤其是提高了小电源侧保护的启动灵敏度,极大地提高了上网变电站的供电可靠性,而且该方案受小电源侧阻抗变化的影响较小。在实践中证明该方案简单有效。

To solve the problems of small power source connected to power networks, such as protection sensitivity on small power source side is so low that sometimes the protection can't start; and after small power source is connected to power networks, power supply reliability of the 110kV transformer substation will decrease, then an practical protection scheme for small power connected to power networks based on the low voltage protection is proposed. Protection theory and configuration of the scheme are very simple, which greatly simplifies the protection setting and operation management, especially enhances the startup sensitivity on small power side and power reliability of the transformer substation. Moreover, the sensitivity is less influenced by small power impedance change. The practice proves the simplicity and efficiency of the proposed scheme.