Adaptive sequential controller

Patent · Sat Jan 01 00:00:00 EST 1994

OSTI ID:869594

El-Sharkawi, Mohamed A ^[1]; Xing, Jian ^[2]; Butler, Nicholas G ^[3]; Rodriguez, Alonso ^[4]

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1. Renton, WA
2. Seattle, WA
3. Newberg, OR
4. Pasadena, CA

An adaptive sequential controller (50/50') for controlling a circuit breaker (52) or other switching device to substantially eliminate transients on a distribution line caused by closing and opening the circuit breaker. The device adaptively compensates for changes in the response time of the circuit breaker due to aging and environmental effects. A potential transformer (70) provides a reference signal corresponding to the zero crossing of the voltage waveform, and a phase shift comparator circuit (96) compares the reference signal to the time at which any transient was produced when the circuit breaker closed, producing a signal indicative of the adaptive adjustment that should be made. Similarly, in controlling the opening of the circuit breaker, a current transformer (88) provides a reference signal that is compared against the time at which any transient is detected when the circuit breaker last opened. An adaptive adjustment circuit (102) produces a compensation time that is appropriately modified to account for changes in the circuit breaker response, including the effect of ambient conditions and aging. When next opened or closed, the circuit breaker is activated at an appropriately compensated time, so that it closes when the voltage crosses zero and opens when the current crosses zero, minimizing any transients on the distribution line. Phase angle can be used to control the opening of the circuit breaker relative to the reference signal provided by the potential transformer.

• DOE Contract Number: BI79-92BP25768
• Assignee: Board of Regents of University of Washington (Seattle, WA)
• Patent Number(s): US 5361184
• OSTI ID: 869594
• Country of Publication: United States
• Language: English

Related Subjects

adaptive
sequential
controller
50
controlling
circuit
breaker
52
switching
device
substantially
eliminate
transients
distribution
line
caused
closing
adaptively
compensates
changes
response
time
due
aging
environmental
effects
potential
transformer
70
provides
reference
signal
corresponding
zero
crossing
voltage
waveform
phase
shift
comparator
96
compares
transient
produced
closed
producing
indicative
adjustment
similarly
current
88
compared
detected
102
produces
compensation
appropriately
modified
account
including
effect
ambient
conditions
activated
compensated
closes
crosses
minimizing
angle
control
relative
provided
voltage waveform
signal corresponding
ambient conditions
current transformer
zero crossing
phase angle
phase shift
reference signal
circuit breaker
response time
signal indicative
switching device
substantially eliminate
crosses zero
comparator circuit
sequential controller
voltage crosses
signal provide
adaptive sequential
distribution line
/361/