Overvoltage Differential Protection of Low Voltage Circuits

2018 ◽  
Author(s):  
R. Burlica ◽  
D. Astanei ◽  
A. Dragomir ◽  
M. Adam
Keyword(s):  
Low Voltage ◽  
Differential Protection ◽  
Low Voltage Circuits

The Feasible Analysis of Transformer Fast Reenergizing with Neutral Point Ungrounded

2013 ◽  
Vol 732-733 ◽  
pp. 958-964
Author(s):  
Yao Zhao ◽  
Yu De Yang ◽  
Yan Hong Pan ◽  
Le Qi
Keyword(s):  
High Voltage ◽  
Power Supply ◽  
Low Voltage ◽  
Second Harmonic ◽  
Neutral Point ◽  
Inrush Current ◽  
Differential Protection ◽  
Time Saving ◽  
Magnetizing Inrush Current ◽  
Transformer Differential Protection

The feasibility of transformer fast reenergizing with neutral point ungrounded after the external fault being removed is analyzed in this paper. By calculating overvoltage and discriminating magnetizing inrush current, it analyzes four ways to restore power of transformer and chooses the optimal strategy which is safe and time-saving. The result shows that in the case of transformer neutral point ungrounded, closing the low-voltage circuit side breaker before the high-voltage, which can effectively limit over-voltage in a safe range. The second harmonic characteristic of magnetizing waveform may disappear, while the intermittent angle characteristics are still significant. With the help of the intermittent angle principle, transformer differential protection may not misuse. The average time for each customer interruption is reduced from 40 minutes to 10 minutes and saves an hour for engineer on the way back and forth. It will greatly improve power supply reliability.

Integrated "Low Voltage" Circuits for Economic Color Decoder Concepts

1970 ◽  
Vol BTR-16 (2) ◽  
pp. 123-130
Author(s):  
S. Gertzis ◽  
H. Thanos ◽  
Th. Leysner ◽  
R. Suhrmann
Keyword(s):  
Low Voltage ◽  
Low Voltage Circuits
Sign in / Sign up

Export Citation Format

Share Document