U.S. patent application number 13/675726 was filed with the patent office on 2014-05-15 for systems and methods for detecting overhead line motion.
This patent application is currently assigned to Elwha LLC. The applicant listed for this patent is ELWHA LLC. Invention is credited to Alistar K. Chan, Jesse R. Cheatham, Geoffrey F. Deane, William Gates, Roderick A. Hyde, Muriel Y. Ishikawa, Jordin T. Kare, Nathan P. Myhrvold, Robert C. Petroski, Clarence T. Tegreene, David B. Tuckerman, Charles Whitmer, Lowell L. Wood, JR..
Application Number | 20140136140 13/675726 |
Document ID | / |
Family ID | 50682533 |
Filed Date | 2014-05-15 |
United States Patent
Application |
20140136140 |
Kind Code |
A1 |
Chan; Alistar K. ; et
al. |
May 15, 2014 |
SYSTEMS AND METHODS FOR DETECTING OVERHEAD LINE MOTION
Abstract
A system for monitoring motion of an overhead line includes a
monitoring device. The monitoring device includes an accelerometer
and a processing circuit. The processing circuit is configured to
accept data from the accelerometer corresponding to line movement,
analyze the data to determine displacement data corresponding to a
displacement of the overhead line, accept data corresponding to a
location of at least one external object proximate to the overhead
line, and analyze the displacement data to determine a clearance
from the at least one external object.
Inventors: |
Chan; Alistar K.;
(Bainbridge Island, WA) ; Cheatham; Jesse R.;
(Seattle, WA) ; Deane; Geoffrey F.; (Bellevue,
WA) ; Gates; William; (Medina, WA) ; Hyde;
Roderick A.; (Redmond, WA) ; Ishikawa; Muriel Y.;
(Livermore, CA) ; Kare; Jordin T.; (Seattle,
WA) ; Myhrvold; Nathan P.; (Medina, WA) ;
Petroski; Robert C.; (Seattle, WA) ; Tegreene;
Clarence T.; (Mercer Island, WA) ; Tuckerman; David
B.; (Lafayette, CA) ; Whitmer; Charles; (North
Bend, WA) ; Wood, JR.; Lowell L.; (Bellevue,
WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ELWHA LLC |
Bellevue |
WA |
US |
|
|
Assignee: |
Elwha LLC
Bellevue
WA
|
Family ID: |
50682533 |
Appl. No.: |
13/675726 |
Filed: |
November 13, 2012 |
Current U.S.
Class: |
702/141 |
Current CPC
Class: |
G01P 15/00 20130101;
G01H 17/00 20130101; H02G 7/14 20130101; H02G 7/18 20130101 |
Class at
Publication: |
702/141 |
International
Class: |
G06F 17/00 20060101
G06F017/00 |
Claims
1. A system for monitoring motion of an overhead line, comprising:
a monitoring device, comprising: an accelerometer; and a processing
circuit configured to: accept data from the accelerometer
corresponding to line movement; analyze the data to determine
displacement data corresponding to a displacement of the overhead
line; accept data corresponding to a location of at least one
external object proximate to the overhead line; and analyze the
displacement data to determine a clearance from the at least one
external object.
2. The system of claim 1, wherein the monitoring device further
comprises a transmitter configured to send data, and wherein the
processing circuit is further configured to use the transmitter to
send the displacement data to a second device.
3-4. (canceled)
5. The system of claim 1, wherein the accelerometer is coupled to
the overhead line.
6. The system of claim 1, wherein the monitoring device further
comprises multiple accelerometers, wherein the multiple
accelerometers are coupled to multiple sites along the length of
the overhead line.
7. (canceled)
8. The system of claim 6, wherein the sites are selected based on a
modal shape of a vibrational mode of the overhead line.
9. The system of claim 1, wherein determining displacement data
includes determining amplitudes of vibrational modes.
10. The system of claim 9, wherein determining displacement data
includes predicting a displacement at a distal site using the
vibrational modes.
11. The system of claim 9, wherein determining displacement data
includes determining a dynamic displacement due to superposition of
the vibrational modes.
12. (canceled)
13. The system of claim 1, wherein determining displacement data
includes determining a displacement as a function of distance along
the overhead line.
14. The system of claim 1, wherein the external object includes at
least one of vegetation, ground, a structure, a second overhead
line.
15-20. (canceled)
21. The system of claim 1, wherein determining a clearance includes
using displacement data corresponding to a second overhead line
sent from a second monitoring device.
22-23. (canceled)
24. The system of claim 1, wherein the overhead line includes at
least one of a power transmission line and a power distribution
line.
25-27. (canceled)
28. The system of claim 1, wherein analyzing the data includes at
least one of using machine learning, using artificial intelligence,
interacting with a database, using pattern recognition, using
numerical calculation, using intelligent control, using neural
networks, and using fuzzy logic.
29. The system of claim 1, wherein the clearance is a closest
approach between a point on the overhead line and the external
object.
30. The system of claim 1, wherein the clearance is a closest
approach between a point on the overhead line and the external
object during one or more vibrational periods of the overhead
line.
31-61. (canceled)
62. A system for detecting a structural failure of an overhead
line, comprising: a monitoring device, comprising: an
accelerometer; and a processing circuit configured to: accept data
from the accelerometer corresponding to line movement; analyze the
data to determine distance excursion data; analyze the distance
excursion data to detect a falling line; and respond to the falling
line with a real-time action.
63. (canceled)
64. The system of claim 62, wherein the monitoring device further
comprises multiple accelerometers, wherein the multiple
accelerometers are coupled to multiple sites along the length of
the overhead line.
65. (canceled)
66. The system of claim 64, wherein the sites are selected based on
a modal shape of a vibrational mode of the overhead line.
67-68. (canceled)
69. The system of claim 62, wherein the processing circuit is
further configured to predict an impact time.
70. (canceled)
71. The system of claim 62, wherein the processing circuit is
further configured to detect an impact of the falling line.
72. The system of claim 62, where the real-time action includes
depowering the overhead line.
73. The system of claim 62, where the real-time action includes
depowering the overhead line prior to an impact.
74. The system of claim 62, where the real-time action includes
enabling a crowbar circuit coupled to the overhead line.
75. The system of claim 62, where the real-time action includes
enabling a crowbar circuit coupled to the overhead line prior to an
impact.
76. The system of claim 62, wherein the monitoring device further
comprises a transmitter configured to send data.
77. (canceled)
78. The system of claim 76, wherein the real-time action includes
using the transmitter to send a warning signal.
79. The system of claim 78, wherein the warning signal comprises
information corresponding to at least one of an imminent loss of
power, a power surge, and impact information.
80-83. (canceled)
84. The system of claim 62, wherein the overhead line includes at
least one of a power transmission line and a power distribution
line.
85-115. (canceled)
116. A system for actively damping motion of an overhead line,
comprising: a monitoring device, comprising: an accelerometer; a
damping device configured to reduce motion of the overhead line;
and a processing circuit configured to: accept data from the
accelerometer corresponding to line movement; analyze the data to
determine displacement data corresponding to a displacement of the
overhead line; analyze the displacement data to determine if the
overhead line needs damping; and deliver control data to the
damping device, wherein the damping device is configured to receive
the control data and produce overhead line damping according to the
control data.
117-118. (canceled)
119. The system of claim 116, wherein the accelerometer is coupled
to the overhead line.
120. The system of claim 116, wherein the monitoring device further
comprises multiple accelerometers, wherein the multiple
accelerometers are coupled to multiple sites along the length of
the overhead line.
121-122. (canceled)
123. The system of claim 116, wherein the processing circuit and
damping device are comounted.
124. The system of claim 116, wherein the processing circuit and
accelerometer are comounted.
125. The system of claim 116, wherein determining displacement data
includes determining amplitudes of vibrational modes.
126. The system of claim 125, wherein determining displacement data
includes predicting a displacement at a distal site using the
vibrational modes.
127. The system of claim 125, wherein determining displacement data
includes determining a dynamic displacement due to superposition of
the vibrational modes.
128. (canceled)
129. The system of claim 116, wherein determining displacement data
includes determining a displacement as a function of distance along
the overhead line.
130. (canceled)
131. The system of claim 116, wherein determining if the overhead
line needs damping includes using displacement data corresponding
to a second overhead line sent from a second monitoring device.
132-135. (canceled)
136. The system of claim 116, wherein determining if the overhead
line needs damping includes comparing the displacement data to
location data corresponding to at least one external object.
137. The system of claim 116, wherein determining if the overhead
line needs damping includes comparing the displacement data to a
threshold value.
138. The system of claim 125, wherein determining if the overhead
line needs damping includes comparing at least one of the
amplitudes of vibrational modes to a threshold value.
139. The system of claim 116, wherein determining if the overhead
line needs damping includes comparing velocity data derived from
the accelerometer data to a threshold value.
140. The system of claim 116, wherein the damping device includes
at least one of a device configured to adjust aerodynamics, a fan,
a line tensioner, a controlled magnet, and a force-controlled
coupling between the overhead line and an external structure.
141-144. (canceled)
145. The system of claim 116, wherein the damping device is further
configured to apply a damping force to oppose oscillatory
velocity.
146. The system of claim 116, wherein the damping device is further
configured to apply a damping force at discrete locations.
147. The system of claim 116, wherein the damping device is further
configured to apply a damping force at locations based on the
displacement data.
148. The system of claim 116, wherein the damping device is further
configured to apply a damping force at locations based on
vibrational modes of the overhead line.
149-208. (canceled)
Description
BACKGROUND
[0001] Overhead lines (e.g., transmission lines, power lines,
suspended lines, etc.) tend to oscillate back and forth. The
oscillations often includes high-amplitude, low-frequency
oscillations of the line due to wind. The oscillations occur most
often in the vertical plane, although horizontal and rotational
motions are also possible. The oscillations of the line cause
fatigue problems both within the line and to any structures to
which the line is coupled. In the case of power lines, the
oscillations add significantly to the stress on coupled insulators
and pylons, which raises the risk of mechanical failure of the
power system. Additionally, the oscillations can have amplitudes
that are sufficient to exceed operating clearances.
SUMMARY
[0002] One exemplary embodiment relates to a system for monitoring
motion of an overhead line. The system includes a monitoring
device, including an accelerometer and a processing circuit. The
processing circuit is configured to accept data from the
accelerometer corresponding to line movement, analyze the data to
determine displacement data corresponding to a displacement of the
overhead line, accept data corresponding to a location of at least
one external object proximate to the overhead line, and analyze the
displacement data to determine a clearance from the at least one
external object.
[0003] Another exemplary embodiment relates to a method of
monitoring line motion. The method includes receiving data from an
accelerometer corresponding to movement of an overhead line,
analyzing the data to determine displacement data corresponding to
a displacement of the overhead line, receiving data corresponding
to a location of at least one external object proximate to the
overhead line, and analyzing the displacement data to determine a
clearance from the at least one external object.
[0004] Another exemplary embodiment relates to a system for
detecting a structural failure of an overhead line. The system
includes a monitoring device, including an accelerometer and a
processing circuit. The processing circuit is configured to accept
data from the accelerometer corresponding to line movement, analyze
the data to determine distance excursion data, analyze the distance
excursion data to detect a falling line, and responding to the
falling line with a real-time action.
[0005] Another exemplary embodiment relates to a method of
detecting a structural failure of a power line. The method includes
receiving data from an accelerometer corresponding to movement of a
power line, analyzing the data to determine distance excursion
data, analyzing the distance excursion data to determine whether
the power line is falling, and responding to a falling power line
with a real-time action.
[0006] Another exemplary embodiment relates to a system for
actively damping motion of an overhead line. The system includes a
monitoring device, including an accelerometer, a damping device
configured to reduce motion of the overhead line, and a processing
circuit. The processing circuit is configured to accept data from
the accelerometer corresponding to line movement, analyze the data
to determine displacement data corresponding to a displacement of
the overhead line, analyze the displacement data to determine if
the overhead line needs damping, and deliver control data to the
damping device, wherein the damping device is configured to receive
the control data and produce overhead line damping according to the
control data.
[0007] Another exemplary embodiment relates to a method of actively
damping overhead line movement. The method includes receiving data
from an accelerometer corresponding to movement of an overhead
line, analyzing the data to determine displacement data
corresponding to a displacement of the overhead line, analyzing the
displacement data to determine if the overhead line needs damping,
delivering control data to a damping device configured to reduce
motion of the overhead line, wherein the control data is configured
to control overhead line damping, and damping the overhead line
using the damping device.
[0008] Another exemplary embodiment relates to a non-transitory
computer-readable medium having instructions stored thereon, the
instructions include instructions to accept data from an
accelerometer corresponding to movement of an overhead line,
instructions to determine displacement data corresponding to a
displacement of the overhead line, instructions to accept data
corresponding to a location of at least one external object
proximate to the overhead line, instructions to analyze the
displacement data, and instructions to determine a clearance from
the at least one external object.
[0009] The invention is capable of other embodiments and of being
carried out in various ways. Alternative exemplary embodiments
relate to other features and combinations of features as may be
generally recited in the claims.
[0010] The foregoing is a summary and thus by necessity contains
simplifications, generalizations and omissions of detail.
Consequently, those skilled in the art will appreciate that the
summary is illustrative only and is not intended to be in any way
limiting. Other aspects, inventive features, and advantages of the
devices and/or processes described herein, as defined solely by the
claims, will become apparent in the detailed description set forth
herein and taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0011] The invention will become more fully understood from the
following detailed description taken in conjunction with the
accompanying drawings wherein like reference numerals refer to like
elements, in which:
[0012] FIG. 1A is a schematic diagram of an acceleration sensor
system for monitoring line motion, including an monitoring device,
suspended power lines, and power transmission towers, shown
according to an exemplary embodiment.
[0013] FIG. 1B is a schematic diagram of an acceleration sensor
system for monitoring line motion, including an monitoring device,
suspended and fallen power lines, and power transmission towers,
shown according to an exemplary embodiment.
[0014] FIG. 2 is a block diagram of a monitoring device, an
accelerometer, a transmitter, a processing circuit, and a receiver,
shown according to an exemplary embodiment.
[0015] FIG. 3 is a detailed block diagram of a processing circuit,
shown according to an exemplary embodiment.
[0016] FIG. 4 is a schematic diagram of an acceleration sensor
system for monitoring line motion, including monitoring devices,
suspended power lines, and a power transmission tower, shown
according to an exemplary embodiment.
[0017] FIG. 5 is a schematic diagram of an acceleration sensor
system for monitoring line motion, including a monitoring device, a
suspended power line, a damping device, and power transmission
towers, shown according to an exemplary embodiment.
[0018] FIG. 6 is a flowchart of a general process for using a
monitoring device to detect and respond to line motion, shown
according to an exemplary embodiment.
[0019] FIG. 7 is a flowchart of a general process for using a
monitoring device to detect and respond to a falling line, shown
according to an exemplary embodiment.
[0020] FIG. 8 is a flowchart of a general process for using a
monitoring device to counteract line motion, shown according to an
exemplary embodiment.
DETAILED DESCRIPTION
[0021] Before turning to the figures, which illustrate the
exemplary embodiments in detail, it should be understood that the
application is not limited to the details or methodology set forth
in the description or illustrated in the figures. It should also be
understood that the terminology is for the purpose of description
only and should not be regarded as limiting.
[0022] Referring generally to the Figures, systems and methods for
using an acceleration sensor to detect line motion are shown and
described. A monitoring device containing an acceleration sensor,
transmitter, and processing circuit may be coupled to a power line.
The monitoring device may be powered by the power line. The power
line may be suspended between two or more transmission towers
(e.g., electricity pylons, lattice towers, suspension towers,
terminal towers, tension towers, transposition towers, etc.). The
transmission tower may utilize insulators, or other appropriate
means of coupling the lines to the tower's arms. In the event of a
gust of wind which induces an oscillation within the suspended
power line, the acceleration sensor detects the oscillation and
provides related data to the processing circuit. The processing
circuit analyzes the data and determines line clearances from
external objects. The external objects may include trees,
structures, other power lines, buildings, etc. The processing
circuit determines clearances between the line and the external
objects based on variations of displacement along the length of the
line, in addition to determining amplitude information. The
processing circuit measures and predicts the actual shape the
displacement due to the oscillation. For example, the displacement
may be larger towards the middle of the line, and lower towards the
support ends to which the line is coupled. The processing circuit
may cause the transmitter to send oscillation and clearance
information to a receiving device. The oscillation and clearance
information may be logged, and later used in determining a need to
trim vegetation, sculpt terrain, decrease cable sag, etc. The
processing circuit may also determine to take real-time action
based on the oscillation and clearance data. For example, if the
processing circuit determined that the line is within a certain
distance to an external object, the action may include reducing a
power transmission or depowering the line.
[0023] In another contemplated scenario, the monitoring device
includes a receiver configured to receive data from a control
center or other monitoring devices. The monitoring device may use
received oscillation data in calculating displacements along the
line. As an example, there may be four monitoring devices along a
particular span of line. The monitoring device may receive
oscillation information from the other three monitoring devices,
and integrate their motion to determine displacements.
[0024] According to another contemplated scenario a monitoring
device containing an acceleration sensor, transmitter, and
processing circuit is coupled to a power line. The power line is
suspended between two or more transmission towers (e.g.,
electricity pylons, lattice towers, suspension towers, terminal
towers, tension towers, transposition towers, etc.). The
transmission tower may utilize insulators, or other appropriate
means of coupling the lines to the tower's arms. In the event of a
gust of wind or other occurrence which causes a failure within the
power line (e.g., a falling line, line breakage, falling tower,
structural failure, etc.), the acceleration sensor detects the
falling line and provides relevant data to the processing circuit.
The processing circuit analyzes the data and may calculate a
predicted time-to-ground impact. The processing circuit may also
determine an actual impact time. The processing circuit may also
determine to take real-time action based on failure. For example,
the action may include depowering the line prior to impact, or
after impact. As another example, the action may include using the
transmitter to send a status signal to a control center. As yet
another example, the action may include using the transmitter to
send a warning signal to other load devices, notifying the devices
of an imminent power loss or power surge.
[0025] According to another contemplated scenario a monitoring
device containing an acceleration sensor, transmitter, and
processing circuit is coupled to a power line. The power line is
suspended between two or more transmission towers (e.g.,
electricity pylons, lattice towers, suspension towers, terminal
towers, tension towers, transposition towers, etc.). The
transmission tower may utilize insulators, or other appropriate
means of coupling the lines to the tower's arms. In the event of a
gust of wind or other occurrence which induces an oscillation
within the power line, the acceleration sensor detects the
oscillation and provides relevant data to the processing circuit.
The processing circuit analyzes the data and may determine to
counter act the oscillations. This may include using the
transmitter to send signals to control damping devices. For
example, the damping devices may include line tensioners or other
means of adjusting line tension, dynamic force couplers to external
structures, fans or other aerodynamic devices, or controlled
magnetic devices (e.g., devices which react with line current),
each configured to counteract an oscillating line.
[0026] For purposes of this disclosure, the term "coupled" means
the joining of two members directly or indirectly to one another.
Such joining may be stationary in nature or moveable in nature and
such joining may allow for the flow of electricity, electrical
signals, or other types of signals or communication between the two
members. Such joining may be achieved with the two members or the
two members and any additional intermediate members being
integrally formed as a single unitary body with one another or with
the two members or the two members and any additional intermediate
members being attached to one another. Such joining may be
permanent in nature or alternatively may be removable or releasable
in nature.
[0027] Referring to FIG. 1A, line motion detection system 100 is
shown according to an exemplary embodiment. Line motion detection
system 100 includes monitoring device 102, power lines 104,
transmission towers 106, and transmission signals 108. Transmission
towers 106 may be electricity pylons, lattice towers, suspension
towers, terminal towers, tension towers, transposition towers, or
any other structures used to support overhead lines. Power lines
104 may be transmission or distribution lines, high voltage AC
lines, high voltage DC lines, or any other type of overhead line.
Monitoring devices 102 are devices configured according to the
systems and methods herein. Monitoring devices 102 include
accelerometers, processing circuits, transmitters, and any other
components necessary to couple monitoring devices 102 to the lines.
Monitoring devices 102 may additionally include receivers, or
components necessary to implement a crowbar circuit. The
transmitters of monitoring devices 102 are depicted as sending
transmission signals 108. The transmission signals 108 may include
information about line oscillations, information about calculated
line clearances, warning information, status information, or any
other relevant information. Transmission signals 108 may be
received by any multitude of devices. For example, receiving
devices may include receivers located at a control center,
receivers mounted on transmission towers 106, or other monitor
devices 102, etc. It should be understood that the scope of the
present disclosure is not limited to a certain number, or
arrangement of monitoring devices 102. For example, a line may have
multiple monitoring devices 102 coupled thereto. As another
example, monitoring devices 102 may be coupled to a tower arm
connected to the line, or any other feasible location on
transmission towers 106. As another example, the monitoring device
may not have on-board processing circuits, but instead transmit
accelerometer data to an external processing circuit.
[0028] Referring to FIG. 1B, line motion detection system 100 is
shown according to an exemplary embodiment. FIG. 1B is generally
the same line motion detection system 100 as described in FIG. 1A.
However, FIG. 1B depicts a system in which one of power lines 104
has failed and fallen to the ground. In this situation, monitoring
device 112 responds to fallen line 110. Monitoring device 112 is
shown as transmitting signal 114. As an example, signal 114 may be
a warning signal sent to a control center, such as one associated
with the line operator, with local public safety authorities, with
a fire department, or the like. As another example, signal 114 may
be a control signal used by a receiving device to automatically
depower fallen line 110. As another example, signal 114 may contain
information for load devices, alerting such devices of a potential
power surge or loss of power.
[0029] Referring to FIG. 2, a block diagram of monitoring device
200 for executing the systems and methods of the present disclosure
is shown. Monitoring device 200 includes accelerometer module 202,
transmitter 204, processing circuit 206. Accelerometer module 202
is generally configured to measure acceleration and contains at
least one accelerometer. Accelerometer module 202 is further
configured to detect the magnitude and direction of acceleration,
and provide measured values to processing circuit 206.
Accelerometer module 202 may be configured for a single axis or for
multiple axes. Accelerometer module 202 may contain multiple
accelerometers, and may measure both linear and angular
acceleration. Accelerometer module 202 may contain additional
components for maintaining angular references (e.g., a gyroscopic
device). Measured acceleration may be provided to processing
circuit 206 as digital values or analog values, and may be in
vector form, etc. Monitoring device 200 may additionally include
receiver 208. Receiver 208 is generally configured to receive
signals from another device. As an example, receiver 208 may be a
wireless receiver configured to receive signals from a control
center. As another example, receiver 208 may be a wireless receiver
configured to receive signals from another monitoring device. While
depicted as separate modules in FIG. 2, Accelerometer module 202,
transmitter 204, processing circuit 206, and receiver 208 may be
part of one integrated device.
[0030] In an exemplary embodiment, monitoring device 200 is coupled
to a high voltage transmission line. Accelerometer module 202
includes a three axis linear accelerometer and a gyroscope.
Transmitter 204 is a long range radio transmitter. Receiver 208 is
an antenna. Accelerometer module 202 provides acceleration and
rotation information to processing circuit 206. Processing circuit
206 analyzes the data according to the systems and methods herein.
Processing circuit uses transmitter 204 to send status reports to a
control center. Processing circuit uses receiver 208 to obtain
configuration information from the control center.
[0031] In another exemplary embodiment, monitoring device 200 is
coupled to a high voltage transmission line. Accelerometer module
202 includes a three axis linear accelerometer and rotational
accelerometer. Transmitter 204 is a long range radio transmitter.
Receiver 208 is an antenna. Accelerometer module 202 provides
acceleration and rotation information to processing circuit 206.
Processing circuit 206 analyzes the data according to the systems
and methods herein. Processing circuit uses transmitter 204 to send
status reports to other monitoring devices. Processing circuit uses
receiver 208 to obtain configuration information from a control
center. It should be understood that accelerometer module 202 is
not limited to a particular selection of accelerometer devices.
Various accelerometer and motion detecting devices are
envisioned.
[0032] Referring to FIG. 3, a more detailed block diagram of
processing circuit 300 for completing the systems and methods of
the present disclosure is shown, according to an exemplary
embodiment. Processing circuit 300 may be processing circuit within
monitoring devices 102 of FIG. 1. Processing circuit 300 is
generally configured to accept data from an accelerometer (e.g.,
accelerometer module 202 of FIG. 2), determine displacements along
the line, analyze the received data to determine characteristics of
line motion, and determine if any action needs to be taken based on
the data. Input may be received continuously or periodically. In
one embodiment, processing circuit 300 receives data corresponding
to the acceleration of a falling power line. Processing circuit 300
analyzes the data and confirms that the line is falling. Processing
circuit 300 may determine that a variety of actions need to be
taken in response to the falling line. As an example, the actions
may include generating the signals necessary to depower the line
prior to the line impacting the ground. Processing circuit 300 may
cause the signals to be transmitted to a receiving device or
control room. As another example, processing circuit 300 may
generate signals necessary to warn other devices of an impending
loss of power or power surge. As another example, processing
circuit 300 may generate signals necessary to control active
damping devices (e.g., aerodynamic devices, lifting or drag
surfaces, fans, line tensioners, magnets, etc.) The active damping
devices may apply damping forces to oppose the oscillations.
Processing circuit 300 may also generate signals to cause the
active damping devices to apply forces at discrete sites along the
line, or at locations based on an oscillation mode or shape of the
line, etc.
[0033] In another embodiment, processing circuit 300 receives data
corresponding to the oscillations of a power line. Processing
circuit 300 analyzes the data and determines displacements along
the line. Processing circuit 300 analyzes the displacement data and
determines line clearances along the line. Processing circuit 300
may compare the line clearance information to the locations of
external objects (e.g., vegetation, the ground, external
structures, etc.). The locations may be acquired from a camera,
from radar, or from other sensors. The locations may be stored in a
digital file, such as a 2D or 3D map file, a database, or other
format. The locations may be transmitted to a monitoring device
containing processing circuit 300 and processing circuit 300 may
add or update stored locations. The clearance information may
represent the closest three dimensional approach of the oscillating
line to an external object. The effect of an oscillation upon
clearance from an external object will generally depend upon the
location of a given line displacement along the span of the line,
i.e., the maximum deflection may occur at mid-span, but not limit
clearance requirements due to an absence of nearby external objects
at the mid-span location; however a smaller displacement close to
one tower may be more limiting because of a nearby external object.
Processing circuit 300 may also compare the line clearance
information to a configuration file storing maximum displacement
tolerances. As an example, processing circuit 300 may determine
that a line is oscillating in a manner that is likely to cause the
line to contact an external object. Processing circuit 300 may
generate necessary signals to transmit a report of this information
to a receiving device. As another example, processing circuit may
log displacement information data over time. The logged data may be
transmitted to a second device for use in determining a need to
trim vegetation, or for use in better arranging the placement of
the lines, etc.
[0034] Processing circuit 300 includes processor 302. Processor 302
may be implemented as a general purpose processor, an application
specific integrated circuit (ASIC), one or more field programmable
gate arrays (FPGAs), a group of processing components, or other
suitable electronic processing components. Processing circuit 300
also includes memory 304. Memory 304 is one or more devices (e.g.,
RAM, ROM, Flash Memory, hard disk storage, etc.) for storing data
and/or computer code for facilitating the various processes
described herein. Memory 304 may be or include non-transient
volatile memory or non-volatile memory. Memory 304 may include
database components, object code components, script components, or
any other type of information structure for supporting the various
activities and information structures described herein. Memory 304
may be communicably connected to the processor 302 and include
computer code or instructions for executing the processes described
herein.
[0035] Memory 304 includes configuration data 306. Configuration
data 306 includes data relating to processing circuit 300. For
example, configuration data 306 may include information relating to
interfacing with an accelerometer. This may include the command set
needed to interface with transmitter and receiver components, for
example a radio transmitter, an antennae, etc. Configuration data
may include specification and protocol information for the
components of an monitoring device as described herein. As another
example, configuration data 306 may include information relating to
tolerances or error levels, which may be used in determining when
an action needs to be taken. Configuration data 306 may include
data to configure the communication between the various components
of processing circuit 300, and the various components of the
systems described herein.
[0036] Configuration data 306 may further include information
relating to external objects. For example, this may include
locations of trees, houses, structures, vegetation, other power
lines, power transmission towers, etc. This location data may
reside in a database, a digital 2D or 3D map, a text file, or the
like. Configuration data 306 may provide this information to
Analysis module 310 for processing. Configuration data 306 may
further include information relating to tolerances and error
conditions. Configuration data 306 may provide this data to
analysis module 310 for use in determining if a dangerous line
condition is present, or for determining if a warning needs to be
transmitted, etc. Configuration data 306 may also include location
information of the corresponding monitoring device.
[0037] Memory 304 includes memory buffer 308. Memory buffer 308 is
configured to receive data from an accelerometer module, (e.g.
accelerometer module 202 of FIG. 2) through input 314. Memory
buffer may also receive data through input 314 from other
components within a monitoring device. The data may include
information provided by a second device. For example, the data may
include configuration or initialization data sent from a control
center. As another example the data may be data sent from a second
monitoring device. Data received through input 314 may be stored in
memory buffer 308 until memory buffer 308 is accessed for data by
the various modules of processing circuit 300. For example,
analysis module 310 may access configuration data that is stored in
memory buffer 308.
[0038] Memory 304 includes analysis module 310. Analysis module 310
is configured to receive line motion data from an accelerometer
device (e.g. accelerometer module 202 of FIG. 2). The line motion
data may be provided through input 314 or through memory buffer
308. Analysis module 310 scans the line motion data and analyzes
the data. Analysis module 310 determines actions to take in
response to the analysis. For example, the actions may include
logging the data, transmitting the data, sending warning or alert
signals, determining line displacements and clearances, enable
damping devices, etc. Analysis module 310 may provide data to be
formatted for transmission by communications module 312. Analysis
module 310 module may use any number of techniques as it performs
analysis as described herein. For example, analysis module may make
use of machine learning, artificial intelligence, interactions with
databases and database table lookups, pattern recognition and
logging, intelligent control, neural networks, and fuzzy logic,
etc.
[0039] In one embodiment, analysis module 310 receives line motion
data from an accelerometer module and determines vibrational
amplitudes of an overhead line. Line motion may be induced by wind,
line or tower failure, etc. The scope of the present disclosure is
not limited to a certain cause of line motion. Analysis module 310
uses the line motion data to calculate vibrational amplitudes along
the line. Analysis module 310 uses the vibrational amplitude
information to determine line clearances from external objects. The
clearances may be determined at general locations along the line
length, not simply at mid-span. To determine line clearances from
external objects, analysis module 310 may use its positional
information (e.g., the location of the accelerometer along the
line) in calculating displacements and characterizing motion of the
line. Analysis module may also access configuration data 308 to
retrieve a data structure containing location information relating
to external objects. Analysis module 310 also uses the line motion
data to determine excitations of line vibrational modes. For
example, this may include calculations relating to a line's normal
mode and relating to standing waves along the line. This may also
include determining amplitudes of the vibrational modes. Analysis
module 310 may use the line vibrational mode information to predict
line displacements at distal sites along the line. Analysis module
310 may store the vibrational mode information and utilize prior
knowledge of modes in predicting future displacements. Analysis
module 310 may determine displacements as a function of distance
along the line, as opposed to only determining peak modal
displacements. Analysis module 310 may determine displacements due
to time varying superposition of modal displacements.
[0040] Analysis module 310 may compare the line displacement
information to external object locations and provide line clearance
information. For example, analysis module 310 may compare the
maximum displacement of a certain location on the line to a
location of a nearby tree. In one embodiment, the comparison
information may be provided to a second device or control center,
and be used in determining a need to trim vegetation or decrease
line sag. For example, analysis module 310 may provide information
that the line's movement exceeded a certain tolerance level (e.g.,
the line was within 5 ft. of the tree, etc.). As another example,
analysis module 310 may provide information that the line's
movement did not exceed a certain tolerance level (e.g., the line
never oscillated greater than a distance of 1 foot, etc.).
Tolerance levels may be specified by configuration data 308. In
another embodiment, the comparison information may be used to
trigger real time action. For example, if the line exceeds a
certain tolerance, analysis module 310 may provide signals
necessary to reduce the power or depower the line.
[0041] In one embodiment, analysis module 310 receives line motion
data from both an accelerometer module and a second monitoring
device (e.g., monitoring device 200 of FIG. 2), determines
vibrational amplitudes of an overhead line using the received data,
and uses the vibrational amplitude information to determine line
clearances from external objects as described herein. Analysis
module 310 may perform integration on received motion information
to determine positional information. Analysis module 310 uses the
data from the second monitoring device in determining dynamic
clearances. For example, if the second monitoring device is coupled
to a second line, analysis module 310 may dynamically calculate the
distance between the lines. Analysis module 310 determines lines
clearances. Analysis module 310 uses the motion information from
the second monitoring device to confirm any determined actions. As
an example, displacement information sent from the second
monitoring device may be confirmed in order to avoid a false
alarm.
[0042] In one embodiment, analysis module 310 receives line motion
data from an accelerometer module for real-time detection of a
falling line. Analysis module 310 may detect the falling line based
on integration of the motion data (e.g., data corresponding to
acceleration) to determine a distance excursion over time. The
falling line may be caused by an actual breakage of the line, or
failure of the line's supports, etc. The distance excursion can
involve vertical or lateral motion. Analysis module 310 may compare
the distance excursion to a tolerance level specified in
configuration data 308. As one example, analysis module 310 may
determine the line has moved a vertical distance greater than the
tolerance level, and may infer that the line is falling. In one
embodiment, analysis module 310 predicts the time-to-impact based
on a line height or distance and the motion data. In another
embodiment, analysis module 310 detects the actual line impact
using the motion data. For example, the motion data may correspond
to a large magnitude, but short duration, acceleration pulse
followed by a continuing period with no acceleration. Analysis
module 310 may determine to take real-time action based on a
falling line. As an example, analysis module 310 may generate the
necessary signals to transmit an impact report to a control center
(e.g., associated with the line operator, with public safety
organizations, etc.). As another example, analysis module 310 may
generate the necessary signals to enable a crowbar circuit to
automatically depower the line. In yet another example, analysis
module 310 may generate the necessary signals to cause another
device to depower the line (e.g., transmitting an alert or control
signal, etc.). Analysis module 310 may transmit such an alert or
control signal prior or after line impact. Communications module
312 may prepare any data provided by analysis module 310 for
transmission. In yet another example, analysis module 310 may
transmit a signal warning of an imminent loss of power or power
surge.
[0043] In one embodiment, analysis module 310 receives line motion
data from an accelerometer module to control active damping of the
line motion (e.g., oscillations, vibrations, etc.). Analysis module
310 uses the line motion data to determine excitation of cable
vibrational modes. In addition to determining displacements and
vibrational modes of the line as described herein, analysis module
310 calculates displacements at the location of the damping
devices. Analysis module 310 determines whether the line requires
damping. As an example, if the line's displacement or velocity at a
certain location exceeds a tolerance level, analysis module 310 may
generate the necessary signals to control a damping device. A
damping device may be any number of damping devices (e.g., line
tensioners, fans, controlled magnets, stays, aerodynamic devices,
articulated lifting or drag surfaces, etc.). The scope of the
present disclosure is not limited to a certain damping device.
Analysis module 310 transmits signals to cause the damping device
to apply damping forces to oppose oscillatory velocity. Analysis
module 310 may use data corresponding to the line analysis
described herein (e.g., displacement calculations, velocity
calculations, vibrational mode calculations, mode shape
calculations, etc.) in determining locations and magnitude of
damping forces to be applied. In one embodiment, analysis module
310 receives additional line motion data from a second monitoring
device (e.g., monitoring device 200 of FIG. 2) in controlling the
active damping of line motion. Analysis module 310 may transmit
information corresponding to any damping applied. For example,
analysis module 310 may send a status report of damping applied to
a control center.
[0044] Memory 304 further includes communications module 312.
Communications module 312 is configured to provide communication
capability with other devices via output 316. As an example,
communications module 312 may be configured to provide information
corresponding to logged line oscillations (e.g., excitation of
cable vibrational modes, amplitudes, displacements, line
clearances, etc.). The other device may be a control center, a
server, another monitoring device, etc. Communications module 312
may include logic for supporting various communications protocols
(e.g., internet protocol (IP), transmission control protocol (TCP),
file transfer protocol (FTP), radio transmissions, etc.) or
supporting server-client or peer-to-peer network relationships.
[0045] Processing circuit 300 further includes input 314 and output
316. Input 314 is configured to receive accelerometer module data,
configuration information, and any other suitable data. Output 316
is configured to provide output to a device as described herein.
For example, output 316 may be configured to connect to other
devices via a wireless transmission. Output 316 may also be
configured to connect to a second device via a wired connection
(e.g., sending transmissions along a line, etc.).
[0046] Referring to FIG. 4, line motion detection system 400 is
shown according to an exemplary embodiment. Line motion detection
system 400 includes monitoring devices 402, power transmission
tower 410, power line 408, insulator 406, and tower arm 404.
Monitoring devices 402 may be configured as described herein (e.g.,
monitoring device 200 of FIG. 2). Monitoring devices 402 may be
coupled to any appropriate location. For example, a monitoring
device may be coupled to tower arm 404 or insulator 406 of
transmission tower 410. As another example, a monitoring device may
be coupled to power line 408. Such monitoring devices may be
configured to communicate with each other to according to the
methods described herein. It should be understood that the present
disclosure is not limited to monitoring devices at a certain
location, and that other locations of monitoring devices are
envisioned.
[0047] Referring to FIG. 5, line motion detection system 500 is
shown according to an exemplary embodiment. Line motion detection
system 500 includes monitoring device 502, power transmission
towers 508, power line 506, and damping device 504. Monitoring
device 502 may be configured as described herein (e.g., monitoring
device 200 of FIG. 2). Monitoring device 502 is depicted as
transmitting a control signal to damping device 504. Damping device
504 receives the control signal from monitoring device 502 and
applies forces to oppose oscillations or movements in line 506. As
an example, damping device 504 may be a line tension device. The
line tension device may increase or decrease the tension of a
suspended line in response to a control signal. Monitoring device
502 may send a control signal in order to actuate the increase or
decrease the tension in line 506, and thereby counteract an
oscillation. As another example, damping device 504 may be an
aerodynamic device capable of adjusting airflow or drag across the
line. Monitoring device 502 may send a control signal to actuate
the aerodynamic device to counteract or disrupt wind in order to
impede line oscillations. Monitoring device 502 and damping device
504 may be physically coupled to each other or may be separate and
communicate by wired or wireless signals.
[0048] Referring to FIG. 6, a flowchart of a general process 600
for using a monitoring device to detect and respond to line motion,
shown according to an exemplary embodiment. Process 600 includes
accepting data from an accelerometer module (e.g., accelerometer
module 202 of FIG. 2, etc.) (step 602), accepting data relating to
known external objects (step 604), performing analysis on the
accelerometer module data to determine cable vibrational modes,
including determining maximum displacements along the line (step
606), and comparing the displacement information to external object
locations and determining line clearances (step 608). In response
to the determined line clearances, an action may be taken (steps
610-614). For example, transmitting the line clearance information
to be logged (step 610), sending an alert signal if necessary (step
612), or sending data to other monitoring devices (step 614). It
should be understood that these actions may be combined, and
multiple actions may be performed. It should be further understood
that the actions are not limited to those mentioned in steps
610-614.
[0049] Referring to FIG. 7, a flowchart of a general process 700
for using a monitoring device to detect and respond to a falling
line, shown according to an exemplary embodiment. Process 700
includes accepting data from an accelerometer module (e.g.,
accelerometer module 202 of FIG. 2, etc.) (step 702), performing
analysis on the accelerometer module (step 704), and determining if
immediate damage-preventative action is required (step 706). If
immediate damage-preventative action is required then perform one,
or multiple, real-time actions (step 708). Real-time actions
include, depowering the line (step 710), crowbarring the line with
a crowbar circuit (step 712), or sending an alert or warning signal
(step 714), etc. It should be understood that these actions may be
combined, and multiple actions may be performed. It should be
further understood that the actions are not limited to those
mentioned in steps 710-714.
[0050] Referring to FIG. 8, a flowchart of a general process 800
for using a monitoring device to counteract line motion, shown
according to an exemplary embodiment. Process 800 includes
accepting data from an accelerometer module (e.g., accelerometer
module 202 of FIG. 2, etc.) (step 802), performing analysis on the
accelerometer module including determination line vibrational modes
and maximum amplitudes (step 804), and determining if immediate
damage-preventative action is required (step 806). If immediate
damage-preventative action is required then perform one, or
multiple, real-time actions (step 808). Real-time actions include,
depowering the line (step 810), crowbarring the line with a crowbar
circuit (step 812), or sending an alert or warning signal (step
814), etc. It should be understood that these actions may be
combined, and multiple actions may be performed. It should be
further understood that the actions are not limited to those
mentioned in steps 810-814. If an immediate damage-preventative
action is not required, other actions may be required (step 816).
These actions (step 818) include, but are not limited to
controlling a damping device (step 820), or transmitting data to
another device (step 822), or logging the data (step 824), etc.
[0051] The present disclosure contemplates methods, systems and
program products on any machine-readable media for accomplishing
various operations. The embodiments of the present disclosure may
be implemented using existing computer processors, or by a special
purpose computer processor for an appropriate system, incorporated
for this or another purpose, or by a hardwired system. Embodiments
within the scope of the present disclosure include program products
comprising machine-readable media for carrying or having
machine-executable instructions or data structures stored thereon.
Such machine-readable media can be any available media that can be
accessed by a general purpose or special purpose computer or other
machine with a processor. By way of example, such machine-readable
media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical
disk storage, magnetic disk storage or other magnetic storage
devices, or any other medium which can be used to carry or store
desired program code in the form of machine-executable instructions
or data structures and which can be accessed by a general purpose
or special purpose computer or other machine with a processor. When
information is transferred or provided over a network or another
communications connection (either hardwired, wireless, or a
combination of hardwired or wireless) to a machine, the machine
properly views the connection as a machine-readable medium. Thus,
any such connection is properly termed a machine-readable medium.
Combinations of the above are also included within the scope of
machine-readable media. Machine-executable instructions include,
for example, instructions and data which cause a general purpose
computer, special purpose computer, or special purpose processing
machines to perform a certain function or group of functions.
[0052] Although the figures may show a specific order of method
steps, the order of the steps may differ from what is depicted.
Also two or more steps may be performed concurrently or with
partial concurrence. Such variation will depend on the software and
hardware systems chosen and on designer choice. All such variations
are within the scope of the disclosure. Likewise, software
implementations could be accomplished with standard programming
techniques with rule based logic and other logic to accomplish the
various connection steps, processing steps, comparison steps and
decision steps.
* * * * *