UK Grid Frequency data in Open-ENF .fredb format

This file contains the mains grid frequency for each second betwen 1st Jan 2014 00:00 UTC and 1st Jan 2022 00:00 UTC. This data was originally published by the UK National Grid, and subsequently cleaned and reformatted in OpenENF .freqdb format本文件包含2014年1月1日00:00 UTC至2022年1月1日00:00 UTC期间每秒的市电电网频率（mains grid frequency）。该数据最初由英国国家电网（UK National Grid）发布，后续经清洗处理并重新格式化为OpenENF .freqdb格式。