我国目前10kV城网供电主要形式为树干式,即一条10kV线路上接有几个乃至十几个用户变配电所。为此,搞好用户变压器的继电保护整定计算,对提高供电的可靠性有着重要的意义。 1 用户变压器过流和速断保护的整定计算 一般设计手册规定,配电变压器过流保 China’s current 10kV city network power supply is mainly in the form of trunk, that is, a 10kV line is connected to several or even more than a dozen user power distribution stations. For this reason, it is of great significance to improve the reliability of the power supply by doing a good job of setting up relay protection settings for the user’s transformer. 1 Set-up calculation of over-current and quick-break protection of the user’s transformer General design manual stipulates that the distribution transformer over-current protection