1 Correction to: Journal of Electrical Engineering & Technology (2019) 14:323–330 https://doi.org/10.1007/s42835-018-00041-5

In the acknowledgement one project number has been changed:

This work was supported by the Science and Technology Project of State Grid Corporation of China (5204DY16000P), the Fundamental Research Funds for the Central Universities (2016XS93) and the National Natural Science Foundation of China (51407074).