Assessment of the number of voltage sags experienced by a large industrial customer

Circuit theory models are used to estimate the number of voltage sags in the power supply to a paper mill. For every voltage level, the radius of the exposed area (the critical distance) gives the expected number of sags. As the main sensitive load is formed by large adjustable-speed drives, a classification of sags into four types is used. The conclusion of the study is that the equipment should first be made resilient against sags due to single-phase faults at 400 kV. These faults cause the majority of sags. Sags due to three-phase faults are more severe (especially due to faults at 11 kV) but are less common.

[1]  Math Bollen,et al.  Fast assessment methods for voltage sags in distribution systems , 1995, IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting.

[2]  L. Morgan,et al.  Voltage sag mitigation through ridethrough coordination , 1994, Proceedings of 1994 IEEE/IAS Annual Textile, Fiber and Film Industry Technical Conference.

[3]  Math Bollen.  Method of critical distances for stochastic assessment of voltage sags , 1998 .

[4]  Math Bollen.  Characterisation of voltage sags experienced by three-phase adjustable-speed drives , 1997 .

[5]  D. Koval,et al.  Proposed chapter 9 for predicting voltage sags (dips) in revision to IEEE Std 493, the Gold Book , 1993, Conference Record Industrial and Commercial Power Systems Technical Conference 1993.

[6]  C. Becker,et al.  Proposed chapter 9 for predicting voltage sags (dips) in revision to IEEE Std 493, the Gold Book , 1993 .