DOWNHOLE SOLENOID ACTUATOR DRIVE SYSTEM
BACKGROUND
Hydrocarbons, such as oil and gas, are commonly obtained from subterranean
formations that may be located onshore or offshore. The development of subterranean
operations and the processes involved in removing hydrocarbons from a subterranean formation
are complex. Typically, subterranean operations involve a number of different steps such as, for
example, drilling a wellbore at a desired well site, treating the wellbore to optimize production of
hydrocarbons, and performing the necessary steps to produce and process the hydrocarbons from
the subterranean formation. In certain instances, communications may take place between the
surface of the well site and downhole elements. These communications may be referred to as
downhole telemetry and may be used to transmit data from downhole sensors and equipment to
computing systems located at the surface, which may utilize the data to inform further operations
in numerous ways.
One type of downhole telemetry utilizes pressure waves in drilling fluid circulated
through the wellbore during a drilling operation. These pressure waves typically are generated
by one or more solenoid actuators that transform electrical energy into mechanical force, altering
the flow of drilling fluid and thereby creating pressure waves that can be received at the surface.
In some cases, hundreds of watts of power may be used to generate the necessary mechanical
force. This amount of power can cause excess heat generation within the solenoid actuator.
FIGURES
Some specific exemplary embodiments of the disclosure may be understood by
referring, in part, to the following description and the accompanying drawings.
Figure 1 is a diagram showing an example subterranean drilling system,
according to aspects of the present disclosure.
Figure 2 is a diagram showing an example telemetry system, according to aspects
of the present disclosure.
Figure 3 is a diagram showing an example solenoid actuator, according to aspects
of the present disclosure.
Figure 4 is a diagram showing an example solenoid drive system, according to
aspects of the present disclosure.
Figure 5 is a diagram showing another example solenoid drive system, according
to aspects of the present disclosure.
Figure 6 is a diagram showing another example solenoid drive system, according
to aspects of the present disclosure.
While embodiments of this disclosure have been depicted and described and are
defined by reference to exemplary embodiments of the disclosure, such references do not imply a
limitation on the disclosure, and no such limitation is to be inferred. The subject matter
disclosed is capable of considerable modification, alteration, and equivalents in form and
function, as will occur to those skilled in the pertinent art and having the benefit of this
disclosure. The depicted and described embodiments of this disclosure are examples only, and
not exhaustive of the scope of the disclosure.
DETAILED DESCRIPTION
For purposes of this disclosure, an information handling system may include any
instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit,
receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or
utilize any form of information, intelligence, or data for business, scientific, control, or other
purposes. For example, an information handling system may be a personal computer, a network
storage device, or any other suitable device and may vary in size, shape, performance,
functionality, and price. The information handling system may include random access
memory (RAM), one or more processing resources such as a central processing unit (CPU) or
hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional
components of the information handling system may include one or more disk drives, one or
more network ports for communication with external devices as well as various input and
output (I/O) devices, such as a keyboard, a mouse, and a video display. The information handling
system may also include one or more buses operable to transmit communications between the
various hardware components. It may also include one or more interface units capable of
transmitting one or more signals to a controller, actuator, or like device.
For the purposes of this disclosure, computer-readable media may include any
instrumentality or aggregation of instrumentalities that may retain data and/or instructions for a
period of time. Computer-readable media may include, for example, without limitation, storage
media such as a direct access storage device (e.g., a hard disk drive or floppy disk drive), a
sequential access storage device (e.g., a tape disk drive), compact disk, CD-ROM, DVD, RAM,
ROM, electrically erasable programmable read-only memory (EEPROM), and/or flash memory;
as well as communications media such wires, optical fibers, microwaves, radio waves, and other
electromagnetic and/or optical carriers; and/or any combination of the foregoing.
Illustrative embodiments of the present disclosure are described in detail herein.
In the interest of clarity, not all features of an actual implementation may be described in this
specification. It will of course be appreciated that in the development of any such actual
embodiment, numerous implementation-specific decisions are made to achieve the specific
implementation goals, which will vary from one implementation to another. Moreover, it will be
appreciated that such a development effort might be complex and time-consuming, but would,
nevertheless, be a routine undertaking for those of ordinary skill in the art having the benefit of
the present disclosure.
To facilitate a better understanding of the present disclosure, the following
examples of certain embodiments are given. In no way should the following examples be read to
limit, or define, the scope of the invention. Embodiments of the present disclosure may be
applicable to horizontal, vertical, deviated, or otherwise nonlinear wellbores in any type of
subterranean formation. Embodiments may be applicable to injection wells as well as
production wells, including hydrocarbon wells. Embodiments may be implemented using a tool
that is made suitable for testing, retrieval and sampling along sections of the formation.
Embodiments may be implemented with tools that, for example, may be conveyed through a
flow passage in tubular string or using a wireline, slickline, coiled tubing, downhole robot or the
like. "Measurement-while-drilling" ("MWD") is the term generally used for measuring
conditions downhole concerning the movement and location of the drilling assembly while the
drilling continues. "Logging-while-drilling" ("LWD") is the term generally used for similar
techniques that concentrate more on formation parameter measurement. Devices and methods in
accordance with certain embodiments may be used in one or more of wireline (including
wireline, slickline, and coiled tubing), downhole robot, MWD, and LWD operations.
The terms "couple," "coupled," and "couples" as used herein are intended to
mean either an indirect or a direct connection. Thus, if a first device couples to a second device,
that connection may be through a direct connection or through an indirect mechanical or
electrical connection via other devices and connections. Similarly, the term "communicatively
coupled" as used herein is intended to mean either a direct or an indirect communication
connection. Such connection may be a wired or wireless connection such as, for example,
Ethernet or LAN. Such wired and wireless connections are well known to those of ordinary skill
in the art and will therefore not be discussed in detail herein. Thus, if a first device
communicatively couples to a second device, that connection may be through a direct
connection, or through an indirect communication connection via other devices and connections.
The present disclosure relates generally to downhole drilling operations and, more
particularly, to a downhole solenoid actuator drive system. As will be described in detail below,
example downhole solenoid actuator drive systems described herein may allow for excess or
stored power with the solenoid actuator to be recaptured at a power supply. This may reduce the
excess heat generation at the solenoid actuator which may increase the response time of the
solenoid actuator and/or allow for the omission of a heat sink from the telemetry system.
Figure 1 is a diagram of an illustrative subterranean drilling system 100 including
a solenoid actuator drive system, according to aspects of the present disclosure. The drilling
system 100 comprises a drilling platform 2 positioned at the surface 102. In the embodiment
shown, the surface 102 comprises the top of a formation 104 containing one or more rock strata
or layers 18a-c, and the drilling platform 2 may be in contact with the surface 102. In other
embodiments, such as in an off-shore drilling operation, the surface 102 may be separated from
the drilling platform 2 by a volume of water.
The drilling system 100 comprises a derrick 4 supported by the drilling platform 2
and having a traveling block 6 for raising and lowering a drill string 8. A kelly 10 may support
the drill string 8 as it is lowered through a rotary table 12. A drill bit 14 may be coupled to the
drill string 8 and driven by a downhole motor and/or rotation of the drill string 8 by the rotary
table 12. As bit 14 rotates, it creates a borehole 16 that passes through one or more rock strata or
layers 18a-c. A pump 20 may circulate drilling fluid through a feed pipe 22 to kelly 10,
downhole through the interior of drill string 8, through orifices in drill bit 14, back to the surface
via the annulus around drill string 8, and into a retention pit 24. The drilling fluid transports
cuttings from the borehole 16 into the pit 24 and aids in maintaining integrity of the borehole 16.
The drilling system 100 may comprise a bottom hole assembly (BHA) 150
coupled to the drill string 8 near the drill bit 14. The BHA may comprise various downhole
measurement tools and sensors, including LWD/MWD elements 26. Example LWD/MWD
elements 26 include antenna, sensors, magnetometers, gradiometers, etc. As the bit extends the
borehole 16 through the formations 18, the LWD/MWD elements 26 may collect measurements
relating to the formation and the drilling assembly.
In certain embodiments, the measurements taken by the LWD/MWD elements 26
and data from other downhole tools and elements may be transmitted to the surface 102 by a
telemetry system 28. In the embodiment shown, the telemetry system 28 is located within the
BHA and communicably coupled to the LWD/MWD elements 26. The telemetry system 28 may
transmit the data and measurements from the downhole elements as pressure pulses or waves in
fluids injected into or circulated through the drilling assembly, such as drilling fluids, fracturing
fluids, etc. The pressure pulses may be generated in a particular pattern, waveform, or other
representation of data, an example of which may include a binary representation of data that is
p tive or negative pressure pulses may be
received at the surface receiver 30 directly, or may be received and re-transmitted via signal repeaters
50. Such signal repeaters may, for example, be coupled to the drill string 8 at intervals, contain
fluidic pulsers and receiver circuitry to receive and re-transmit corresponding pressure signals, and
aide in the transmission of high frequency signals from the telemetry system 28, which would
otherwise attenuate before reaching the surface receiver 30. The drilling system 100 may further
comprise an information handling system 32 positioned at the surface 102 that is communicably
coupled to the surface receiver 30 to receive telemetry data from the LWD/MWD elements 26
and process the telemetry data to determine certain characteristics of the formation 104.
Figure 2 is a diagram illustrating an example embodiment of the telemetry system
28, according to aspects of the present disclosure. The telemetry system 28 may comprise a
solenoid actuator 202 and a solenoid actuator drive system 204 electrically coupled to the
solenoid actuator 202. The solenoid actuator 202 and solenoid actuator drive system 204 may be
coupled to a drill collar 206, which may be coupled to a drill string 8 when the telemetry system
28 is deployed within the borehole 16. In the embodiment shown, the solenoid actuator 202 and
the drive system 204 are located within an housing 208 coupled to an interior surface of the drill
collar 206 and positioned within an inner bore 210 of the drill collar 206. The housing 208 may
allow drilling fluid flow through the inner bore 210 via one or more channels or annular areas
between the housing 208 and the drill collar 206. In other embodiments, one of the solenoid
actuator 202 and the downhole solenoid actuator drive system 204 may be located in the outer
tubular structure of the drill collar 206 to provide greater fluid flow through the bore 210.
Additionally, although one drill collar 206 is shown, multiple drill collars may be used.
The telemetry system 28 may further comprise a power supply 212 coupled to the
drive system 204. The power supply 212 may comprise a bank of capacitors that are capable of
storing and quickly providing the large amounts of power necessary to trigger the solenoid
actuator 202. In certain embodiments, the power supply 212 may also be coupled to a power
source (not shown) that provides the power stored in the capacitor bank. Example power sources
include battery packs or fluid-driven electric generators. In the embodiment shown, the power
supply 212 is located in the housing 208 with the drive system 204, although other locations are
possible, including outside of the drill collar 206. Additionally, the power supply 212 may be
incorporated into drive system 204.
The drive system 204 may selectively couple one or more solenoids of the
solenoid actuator 202 to the power supply 212 to cause the actuator to move between first and
second positions, which may correspond to positions of an element coupled to the solenoid
. , uator 202 is coupled to a gate valve 214
that is movable between fixed positions within a chamber 216 in the housing 208. These fixed
positions may comprise an "open" position in which the gate valve 214 completes a fluid conduit
216 between the inner bore 210 and an annulus 218 between the drill collar 206 and the borehole
16; and a "close" position when the gate valve 214 blocks the fluid conduit 216. When the gate
valve 214 moves to the "open" position from the "close" position, drilling fluid flowing within
the inner bore 210 may exit into the annulus 208, causing a decrease in the drilling fluid volume
within the inner bore 210 and a corresponding drop in pressure in the drilling fluid that may
propagate upwards to the surface through the drill string 8. Conversely, when the gate valve 214
moves to the "close" position from the "open" position, it may cause an in the drilling fluid
volume within the inner bore 210 and a corresponding increase in pressure in the drilling fluid.
Accordingly, by toggling the gate valve 214 between "open" and "close" positions, the solenoid
actuator 202 and drive system 204 may generate pressure pulses within the drilling fluid that are
used to communicate downhole data to the surface.
Fig. 3 is a diagram of an example solenoid actuator 300, according to aspects of
the present disclosure. The actuator 300 may comprise a main armature 301 at least partially
positioned within an outer housing 302, which may be made of a ferrous material. The actuator
300 may further comprise at least one solenoid used to move and secure the main armature 301
in first and second axial positions with respect to the outer housing 302. The armature 301 may
comprise an end 303 that at least partially extends from the housing 302 to allow the armature
301 to be coupled to a movable element, such as the gate valve described above. The movable
element then may be toggled between fixed axial positions with respect to the actuator 300 by
causing the armature 301 to move within the housing 302.
In the embodiment shown, the actuator 300 comprises a latchable push-pull
solenoid actuator with three solenoids: a first solenoid 303, a second solenoid 304, and third
solenoid 305. The third solenoid 305 may be referred to as a latch solenoid and may cooperate
with a latch armature 306, spring 307, and latch balls 308 to selectively mechanically secure the
armature 301 in a first axial position within the housing 302. The first axial position may be
characterized by the armature 301 being shifted towards the second and third solenoids 304/305.
As shown in Fig. 3, when the armature 301 is in the first axial position and the first solenoid 303
is not energized, the spring 307 may urge the latch armature 306 towards the armature 301 such
that the latch armature 306 forces the latch balls 308 into indentations in the armature 301 to
prevent axial movement by the armature 301. When the third solenoid 305 is energized, it may
overcome the spring force applied b h i 307 h l h armature 306, thereby moving
the latch armature 306 away from the armature 301. This may cause the latch balls 308 to
disengage with the armature and allow axial movement of the armature 301 within the housing
302.
The first and second solenoids 303/304 may be responsible for moving the
armature 301 between first and second axial positions once the latch armature 306 and latch balls
308 are disengaged. In the embodiment shown, the first solenoid 303 may be energized to move
the armature 301 from the first axial position to the second axial position, characterized by the
armature 301 being shifted towards the first solenoid 303. Conversely, the second solenoid 304
may be energized to move the armature 301 from the second axial position to the first axial
position. In certain embodiments, the second axial position of the armature 301 may correspond
to an "open" position of a movable element coupled to the armature 301, and the first axial
position of the armature may correspond to a "close" position. In those embodiments, the first
solenoid 303 may be referred to as an "open" solenoid that is responsible for shifting a movable
element coupled to the armature 301 to the "open" position, and the second solenoid 304 may be
referred to as a "close" solenoid that is responsible for shifting a movable element coupled to the
armature 301 to the "close" position. Notably, the latch solenoid 305 may mechanically secure
the armature 301 in the first axial position or "close" position in the embodiment shown, but may
mechanically secure the armature 301 in the "open" position in other embodiments. Likewise,
the "open" and "close" function of the solenoids may change depending on the configuration of
the actuator 300 and the movable element coupled to the armature 301. Additionally, the
configuration of actuator 300 shown in Fig. 3 is not intended to be limiting.
Energizing the solenoids 303-305 may comprise selectively coupling the
solenoids 303-305 to a power supply. Current may flow through the selected solenoid(s),
generating a corresponding magnetic fields that impart force to and control the movement of the
armatures. In a telemetry system, energizing the solenoids 303-305 may require hundreds of
watts of power because of a high differential pressure drop and the quick actuation times needed
to pulse telemetry. The differential pressure drop may comprise a few thousand pounds-persquare-
inch (psi) across the movable element coupled to the solenoid actuator 300, causing very
high mechanical friction that demands a high drive force at the solenoids 303-305. The quick
actuation time may require high drive force in order to overcome actuator inertia within a small
time interval. The drive force needed at the actuator 300 positivity correlates with the power
consumption at the solenoids 303-305.
Typical solenoids are not energy efficient and only achieve about 50% energy
transformation from electrical power into mechanical force. The rest of the energy is converted
into heat. In practice, solenoids may need to store sufficient energy before to generating the
required mechanical force, and the stored energy may be converted into heat. When coupled
with the high drive force necessary for downhole telemetry, the stored energy may represent a
substantial part of the total energy usage and cause excessive heat generation. This heat can
damage sensitive electronic components unless a secondary heat dissipation system, such as a
heat sink, is used, or the heat generation is reduced by limiting the actuation frequency of the
actuator.
According to aspects of the present disclosure, a solenoid drive system may be
used to recapture and/or reuse stored energy from the solenoids of a solenoid actuator rather than
allowing the energy to be dissipated as heat. In certain embodiments, the stored energy may be
recaptured at a power supply coupled to the solenoids, allowing the energy to be reused to
energize other solenoids of the actuator. In certain embodiments, the stored energy may also be
transmitted from one solenoid of an actuator to another solenoid of the actuator such that stored
energy from one solenoid may be used to energize another solenoid. Recapturing and reusing
the stored energy may reduce the heat generated by solenoid actuator, reduce the need for a heat
sink within the drive system, reduce the total power consumption so that a smaller power supply
can be used, and potentially increase the frequency of the solenoid actuator, which may increase
the transmission capability of a telemetry system incorporating the solenoid drive system.
Fig. 4 is a diagram showing an example solenoid drive system 400, according to
aspects of the present disclosure. In the embodiment shown, the drive system 400 comprises a
plurality of switches S1-S8, which may be used to selectively couple the solenoids of a solenoid
actuator to the positive and negative terminals of a power supply, POW+ and POWrespectively.
The switches S1-S8 may comprise solid state switches that may be closed by the
application of a control current or voltage. Examples include are not limited to metal-oxidesemiconductor
field-effect transistors (MOSEFT), junction gate field-effect transistors ("JEFT"),
or insulated-gate bipolar transistors (IGBT). Analog or mechanical switches may also be used
within the scope of this disclosure.
In certain embodiments, the drive system may comprise a controller (not shown)
that selectively outputs control currents or voltages to the switches S1-S8 to cause the switches
SI-S8 to open and close in a pre-determined sequence, as will be described below, each time the
solenoid actuator is to be triggered. The controller may comprise a processor, such as a
microprocessor, microcontroller, digital signal processor (DSP), application specific integrated
circuit (ASIC), or any other digital or analog circuitry configured to interpret and/or execute
program instructions and/or process data. In some embodiments, the processor may be
communicatively coupled to memory, either integrated with the processor or in a separate
memory device, and may be configured to interpret and/or execute program instructions and/or
data stored in memory. The program instructions may cause the processor to output voltages or
currents to the switches S1-S8 according to the pre-determined sequence. The decision to trigger
the actuator may be made at the controller that outputs the voltages and current to the switches
S1-S8, or by a separate controller communicably coupled to the controller that outputs the
voltages and current to the switches S1-S8.
In the embodiment shown, the solenoid actuator to which the drive system 400 is
coupled comprises a latchable push-pull solenoid actuator with a "latch" solenoid, an "open"
solenoid, and a "close" solenoid. The latch, open, and close solenoids may be connected in
series. Each of the latch, open, and close solenoids may be coupled to the power supply through
more than one of the switches S1-S8. In the embodiment shown, the drive system 400
comprises four current pathways 401-404 coupled to POW+, with each comprising one of the
switches S1-S8 and each being electrically coupled to one terminal of one of the latch, open, and
close solenoids. The current pathways 401-404 may comprise wires or segments of wire, for
example. In the embodiment shown, current pathway 401 includes switch SI and is coupled to a
terminal 405 of the latch solenoid; current pathway 402 includes switch S3 and is coupled to a
terminal 406 common to the latch solenoid and the open solenoid; current pathway 403 includes
switch S5 and is coupled to a terminal 407 common to the open solenoid and the close solenoid;
and current pathway 404 includes switch S7 and is coupled to a terminal 408 of the close
solenoid. The drive system 400 also comprises four current pathways 409-412 coupled to POW-
, with each comprising one of the switches S1-S8 and each being electrically coupled to one
terminal of one of the latch, open, and close solenoids. In the embodiment shown, current
pathway 409 includes switch S2 and is coupled to terminal 405; current pathway 410 includes
switch S4 and is coupled to a terminal 406; current pathway 4 11 includes switch S6 and is
coupled to a terminal 407; and current pathway 412 includes switch S8 and is coupled to a
terminal 408.
As stated above, a controller of the drive system 400 may selectively open and
close the switches S1-S8 according to a pre-determined sequence. An example sequence is
illustrated in Fig. 4 as stages 0-8 of the drive system 400. Stage 0 corresponds to a default
position in which all switches S1-S8 are open, none of the solenoids are energized, and the
solenoid actuator is locked in a close position. Once the controller determines to move the
solenoid actuator to an open position, it may enter Stage 1, in which switches S3 and S2 are
closed to allow current to flow through and begin energizing the latch solenoid. After a time
delay that depends on the current value and the time necessary to energize the latch solenoid
based on that current value, the controller may enter Stage 2, in which switch S6 is closed such
that both the latch solenoid and the open solenoid are being energized. At Stage 3, switch S2
may be opened and switch SI may be closed to allow the fully energized latch solenoid to
maintain its charge while the open solenoid continues to charge. Notably, when the latch
solenoid is fully energized, it may release an armature of the solenoid actuator, allowing it to
move axially.
Once the open solenoid is fully charged, the controller may enter Stage 4, in
which switch S4 is closed and switch S3 is opened. Closing switch S4 allows the open solenoid
to maintain it full charge, which may cause an armature of the actuator to move to and stay in an
open position. Additionally, opening switch S3 allows the latch solenoid to discharge its stored
energy back to POW+, which may store the energy to be used later. This is in contrast to
disconnecting the latch solenoid from the power supply, as is done typically, in which case the
stored energy cannot be discharged from the latch solenoid but is rather dissipated as heat. At
Stage 5, the switch SI may be opened because the latch solenoid is fully discharged and no
longer needs a current pathway to POW+. Switches S4 and S6 may remain closed, maintaining
the full charge of the open solenoid.
Once the armature has moved into the open position, the controller may move to
Stage 6, in which the close solenoid begins charging to move the armature back to a close
position. In particular, switches S5 and S8 may be closed to generate a current flow through the
close solenoid to charge. Stage 6 may also be characterized by the discharge of energy from the
open solenoid. Here, switch S6 is opened to force energy from the open solenoid to be
discharged through the close solenoid. Accordingly, the energy stored within the open solenoid
is used to charge the close solenoid, reusing the energy and reducing the energy that must be
drawn from the power supply. This is in contrast to disconnecting the open solenoid from the
power supply, as is typically done, causing the open solenoid to dissipate stored energy as heat
and the close solenoid to be fully energized using energy from the power supply.
Once the open solenoid is fully discharged at stage 7, switch S4 may be opened
and switches S5 and S8 may remain closed to allow the close solenoid to be fully energized.
Once the close solenoid is fully energized and the armature has moved back to the close position,
the controller may enter stage 8 in which switches S5 and S8 are opened and switches S6 and S7
are closed. This allows the close solenoid to discharge the stored energy back to the power
supply, preventing the energy from being dissipated in the close solenoid as heat. Once the close
solenoid has been fully discharged, the controller may again enter stage 0 until the controller
again determines to trigger the actuator.
In certain embodiments, different configurations and placements of switches may
be used to allow the solenoids to discharge stored energy to the power supply or other solenoids.
Additionally, some of the switches may be removed. Fig. 5 is a diagram showing the drive
system 400 in which switches SI, S4 and S7 have been removed an replaced with diodes Dl,
D3, and D2, respectively. These diodes may comprise freewheeling diodes that are oriented to
allow the current flows indicated in stages 3, 6 and 8 of Fig. 4 that function to discharge the
energy stored in the latch, open, and close solenoids. In certain instances, the diodes Dl, D3,
and D2 may simplify the control steps by reducing the number of switches that must be
controlled by the drive system 400.
Fig. 6 is a diagram showing another example solenoid drive system 500,
according to aspects of the present disclosure. In the embodiment shown, the drive system 500
comprises a plurality of switches S1-S4 and a plurality of diodes D1-D5 that are configured to
control a latchable push-pull solenoid actuator with a "latch" solenoid, an "open" solenoid, and a
"close" solenoid. Here, the latch, open, and close solenoids are arranged in a D-mode system,
and the switches S1-S4 and diodes D1-D5 may selectively couple the solenoids of a solenoid
actuator to the positive and negative terminals of a power supply, POW+ and POWrespectively,
and allow the solenoids to discharge stored energy to the power supply or other
solenoids. In particular, each of the latch, open, and close solenoids may be coupled to the
power supply through a plurality of switches. The drive system 500 may further comprise a
controller that functions similar to the one described above with respect to Fig. 4.
In the embodiment shown, the drive system 500 comprises three current pathways
501-503 coupled to POW+, with each comprising one of the switches S1-S4 and diodes D1-D5
and each being electrically coupled to one terminal of one of the latch, open, and close solenoids.
In the embodiment shown, current pathway 501 includes diode Dl and is coupled to a terminal
504 common to the close solenoid, and to the latch solenoid through an intermediate diode D3;
current pathway 502 includes switch S2 and is coupled to a terminal 505 common to the latch
solenoid and the open solenoid; and current pathway 503 includes switch S3 and is coupled to a
terminal 506 common to the close solenoid through an intermediate diode D2, and to the open
solenoid through an intermediate diode D4. The drive system 500 also comprises three current
pathways 507-509 coupled to POW-, with each comprising one of the switches S1-S4 and diodes
D1-D5 and each being electrically coupled to one terminal of one of the latch, open, and close
solenoids. In the embodiment shown, current pathway 507 includes switch SI and is coupled to
terminal 504; current pathway 508 includes diode D5 and is coupled to terminal 505; and current
pathway 509 includes switch S4 and is coupled to terminal 506.
A controller (not shown) of the drive system 500 may open and close the switches
S1-S4 according to a pre-determined sequence to selectively couple the latch, open, and close
solenoids to the power supply and allow the latch, open, and close solenoids to discharge stored
energy to the power supply or other solenoids. An example sequence is illustrated in Fig. 6 as
stages 0-6. Stage 0 corresponds to a default position in which all switches S1-S4 are open, none
of the solenoids are energized, and the solenoid actuator is locked in a close position. Once the
controller determines to move the solenoid actuator to an open position, it may enter Stage 1, in
which switches SI and S2 are closed to allow current to flow through and begin energizing the
latch solenoid. In addition to current flowing through the latch solenoid, current may also flow
through the open solenoid, diodes D4 and D4, and close solenoid, energizing the open and close
solenoid in series. At stage 2, switch S4 may be closed, such that the latch solenoid and open
solenoid continue charge, but current flowing through the open solenoid travels through switch
S4 instead of the close solenoid. The close solenoid may be freewheeling in stage 2, generating
a secondary current flow and discharging energy though the diode D2. Once the latch solenoid
is fully charged, the controller may move to stage 3, in which the switch SI is opened and
switches S2 and S4 remain closed, allowing the latch solenoid to maintain full energy while the
open solenoid continues to charge. When full energized, the latch solenoid may allow the
armature of the solenoid actuator to move from the close position to the open position.
At stage 4, the open solenoid may be fully energized and move the armature to
the open position. The controller may open switch SI, allowing the open solenoid to maintain its
energy while allowing the latch solenoid to discharge its stored energy to POW+ through the
diodes D3 and D5. At stage 5, the switches SI and S3 may be closed, allowing the open
solenoid to discharge its stored energy to POW+ and the closed solenoid, as well as charging the
close solenoid. At stage 6, switch S4 may be closed to allow the close solenoid to discharged its
stored energy to POW+. When the close solenoid is fully discharged, the controller may again
enter stage 0 until the controller next determines it needs to trigger the actuator.
According to aspects of the present disclosure, an example method for driving a
solenoid actuator includes providing at least one solenoid of the solenoid actuator coupled to a
power supply through a plurality of switches. The at least one solenoid of the solenoid actuator
may be energized by closing at least one switch of the plurality of switches. Energy from the at
least one solenoid may be discharged to the power supply or another solenoid of the solenoid
actuator by at least one of opening the at least one switch of the plurality of switches and closing
at least one other switch of the plurality of switches.
In certain embodiments, providing at least one solenoid of the solenoid coupled to
the power supply through the plurality of switches comprises providing a latch solenoid, an open
solenoid, and a close solenoid coupled to the power supply through the plurality of switches. In
certain embodiments, providing the latch solenoid, the open solenoid, and the close solenoid
coupled to the power supply through the plurality of switches comprises providing the latch
solenoid, the open solenoid, and the close solenoid in series with each terminal of the each of the
latch solenoid, the open solenoid, and the close solenoid coupled to the power supply through at
least one of a switch of the plurality of switches or a diode. In certain embodiments, energizing
at least one solenoid of the solenoid actuator by closing at least one switch of the plurality of
switches comprises energizing the latch solenoid by closing a switch between a first lead of the
power supply and a common terminal between the latch solenoid and the open solenoid and a
switch between a second lead of the power supply and another terminal of the latch solenoid; and
discharging energy from the at least one solenoid to the power supply or another solenoid of the
solenoid actuator by closing at least one other switch of the plurality of switches comprises
discharging energy from the latch solenoid by closing a switch between the first lead of the
power supply and the another terminal of the latch solenoid and a switch between the second
lead of the power supply and the common terminal between the latch solenoid and the open
solenoid.
in certain embodiments, energizing at least one solenoid of the solenoid actuator
by closing at least one switch of the plurality of switches comprises energizing the open solenoid
by closing a switch between a first lead of the power supply and a common terminal between the
latch solenoid and the open solenoid and a switch between a second lead of the power supply and
a common terminal between the open solenoid and the close solenoid; and discharging energy
from the at least one solenoid to the power supply or another solenoid of the solenoid actuator by
closing at least one other switch of the plurality of switches comprises discharging energy from
the open solenoid by closing a switch between the first lead of the power supply and a common
terminal between the latch solenoid and the open solenoid and a switch between the second lead
of the power supply and another terminal of the close solenoid. In certain embodiments,
energizing at least one solenoid of the solenoid actuator by closing at least one switch of the
plurality of switches comprises energizing the close solenoid by closing a switch between a first
lead of the power supply and a common terminal between the open solenoid and the close
solenoid and a switch between a second lead of the power supply and another terminal of the
close solenoid; and discharging energy from the at least one solenoid to the power supply or
another solenoid of the solenoid actuator by closing at least one other switch of the plurality of
switches comprises discharging energy from the close solenoid by closing a switch between the
first lead of the power supply and the another terminal of the close solenoid and a switch
between the second lead of the power supply and the common terminal between the open
solenoid and the close solenoid.
In certain embodiments, providing the latch solenoid, the open solenoid, and the
close solenoid coupled to the power supply through the plurality of switches comprises providing
the latch solenoid, the open solenoid, and the close solenoid in a delta configuration with each
terminal of the each of the latch solenoid, the open solenoid, and the close solenoid coupled to
the power supply through at least one of a switch of the plurality of switches or a diode. In
certain embodiments, energizing at least one solenoid of the solenoid actuator by closing at least
one switch of the plurality of switches comprises energizing the latch solenoid by closing a first
switch between a first lead of the power supply and a common terminal between the latch
solenoid and the open solenoid and a second switch between a second lead of the power supply
and another terminal of the latch solenoid; and discharging energy from the at least one solenoid
to the power supply or another solenoid of the solenoid actuator comprises discharging energy
from the latch solenoid by opening the first and second switches. In certain embodiments,
energizing at least one solenoid of the solenoid actuator by closing at least one switch of the
plurality of switches comprises energizing the open solenoid by closing a switch between a first
lead of the power supply and a common terminal between the latch solenoid and the open
solenoid and a switch between a second lead of the power supply and a common terminal
between the open solenoid and the close solenoid; and discharging energy from the at least one
solenoid to the power supply or another solenoid of the solenoid actuator comprises discharging
energy from the open solenoid by closing a switch between the first lead of the power supply and
the common terminal between the open solenoid and the close solenoid. In certain
embodiments, energizing at least one solenoid of the solenoid actuator by closing at least one
switch of the plurality of switches comprises energizing the close solenoid by closing a switch
between a first lead of the power supply and a common terminal between the open solenoid and
the close solenoid and a switch between a second lead of the power supply and a common
terminal between the close solenoid and the latch solenoid; and discharging energy from the at
least one solenoid to the power supply or another solenoid of the solenoid actuator comprises
discharging energy from the close solenoid by closing a switch between the second lead of the
power supply and the common terminal between the open solenoid and the close solenoid.
According to aspects of the present disclosure, an example system comprises a
solenoid actuator with at least one solenoid; a power supply coupled to the at least one solenoid
through a plurality of switches; and a controller electrically coupled to the plurality of switches,
the controller comprising a processor and a memory device coupled to the process. The memory
device may contain a set of instructions that, when executed by the processor cause the processor
to energize at least one solenoid of the solenoid actuator by closing at least one switch of the
plurality of switches; and discharge energy from the at least one solenoid to the power supply or
another solenoid of the solenoid actuator by at least one of opening the at least one switch of the
plurality of switches and closing at least one other switch of the plurality of switches.
In certain embodiments, the at least one solenoid of the solenoid actuator
comprises a latch solenoid, an open solenoid, and a close solenoid. In certain embodiments, the
latch solenoid, the open solenoid, and the close solenoid are electrically in series with each
terminal of the each of the latch solenoid, the open solenoid, and the close solenoid coupled to
the power supply through at least one of a switch of the plurality of switches or a diode. In
certain embodiments, the set of instructions that cause the processor to energize at least one
solenoid of the solenoid actuator by closing at least one switch of the plurality of switches
further causes the processor to energize the latch solenoid by closing a switch between a first
lead of the power supply and a common terminal between the latch solenoid and the open
solenoid and a switch between a second lead of the power supply and another terminal of the
latch solenoid; and the set of instructions that cause the processor to discharge energy from the at
least one solenoid to the power supply or another solenoid of the solenoid actuator by closing at
least one other switch of the plurality of switches further causes the processor to discharge
energy from the latch solenoid by closing a switch between the first lead of the power supply and
the another terminal of the latch solenoid and a switch between the second lead of the power
supply and the common terminal between the latch solenoid and the open solenoid. In certain
embodiments, the set of instructions that cause the processor to energize at least one solenoid of
the solenoid actuator by closing at least one switch of the plurality of switches further causes the
processor to energize the open solenoid by closing a switch between a first lead of the power
supply and a common terminal between the latch solenoid and the open solenoid and a switch
between a second lead of the power supply and a common terminal between the open solenoid
and the close solenoid; and the set of instructions that cause the processor to discharge energy
from the at least one solenoid to the power supply or another solenoid of the solenoid actuator by
closing at least one other switch of the plurality of switches further causes the processor to
discharge energy from the open solenoid by closing a switch between the first lead of the power
supply and a common terminal between the latch solenoid and the open solenoid and a switch
between the second lead of the power supply and another terminal of the close solenoid. In
certain embodiments, the set of instructions that cause the processor to energize at least one
solenoid of the solenoid actuator by closing at least one switch of the plurality of switches
further causes the processor to energize the close solenoid by closing a switch between a first
lead of the power supply and a common terminal between the open solenoid and the close
solenoid and a switch between a second lead of the power supply and another terminal of the
close solenoid; and the set of instructions that cause the processor to discharge energy from the
at least one solenoid to the power supply or another solenoid of the solenoid actuator by closing
at least one other switch of the plurality of switches further causes the processor to discharge
energy from the close solenoid by closing a switch between the first lead of the power supply
and the another terminal of the close solenoid and a switch between the second lead of the power
supply and the common terminal between the open solenoid and the close solenoid.
In certain embodiments, the latch solenoid, the open solenoid, and the close
solenoid are arranged in a delta configuration with each terminal of the each of the latch
solenoid, the open solenoid, and the close solenoid coupled to the power supply through at least
one of a switch of the plurality of switches or a diode. In certain embodiments, the set of
instructions that cause the processor to energize at least one solenoid of the solenoid actuator by
closing at least one switch of the plurality of switches further causes the processor to energize
the latch solenoid by closing a first switch between a first lead of the power supply and a
common terminal between the latch solenoid and the open solenoid and a second switch
between a second lead of the power supply and another terminal of the latch solenoid; and the set
of instructions that cause the processor to discharge energy from the at least one solenoid to the
power supply or another solenoid of the solenoid actuator further causes the processor to
discharge energy from the latch solenoid by opening the first and second switches. In certain
embodiments, the set of instructions that cause the processor to energize at least one solenoid of
the solenoid actuator by closing at least one switch of the plurality of switches further causes the
processor to energize the open solenoid by closing a switch between a first lead of the power
supply and a common terminal between the latch solenoid and the open solenoid and a switch
between a second lead of the power supply and a common terminal between the open solenoid
and the close solenoid; and the set of instructions that cause the processor to discharge energy
from the at least one solenoid to the power supply or another solenoid of the solenoid actuator
further causes the processor to discharge energy from the open solenoid by closing a switch
between the first lead of the power supply and the common terminal between the open solenoid
and the close solenoid. In certain embodiments, the set of instructions that cause the processor to
energize at least one solenoid of the solenoid actuator by closing at least one switch of the
plurality of switches further causes the processor to energize the close solenoid by closing a
switch between a first lead of the power supply and a common terminal between the open
solenoid and the close solenoid and a switch between a second lead of the power supply and a
common terminal between the close solenoid and the latch solenoid; and the set of instructions
that cause the processor to discharge energy from the at least one solenoid to the power supply or
another solenoid of the solenoid actuator further causes the processor to discharge energy from
the close solenoid by closing a switch between the second lead of the power supply and the
common terminal between the open solenoid and the close solenoid.
In any embodiment described in the preceding three paragraphs, the switches may
comprise solid state switches. In any embodiment described in the preceding three paragraphs,
the system may further comprise a housing of a downhole telemetry system, wherein the
solenoid actuator is coupled to the housing.
Therefore, the present disclosure is well adapted to attain the ends and advantages
mentioned as well as those that are inherent therein. The particular embodiments disclosed
above are illustrative only, as the present disclosure may be modified and practiced in different
but equivalent manners apparent to those skilled in the art having the benefit of the teachings
herein. Furthermore, no limitations are intended to the details of construction or design herein
shown, other than as described in the claims below. It is therefore evident that the particular
illustrative embodiments disclosed above may be altered or modified and all such variations are
considered within the scope and spirit of the present disclosure. Also, the terms in the claims
have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the
patentee. The indefinite articles "a" or "an," as used in the claims, are defined herein to mean
one or more than one of the element that it introduces.

What is claimed is:
1. A method for driving a solenoid actuator, comprising:
providing at least one solenoid of the solenoid actuator coupled to a power supply
through a plurality of switches;
energizing at least one solenoid of the solenoid actuator by closing at least one
switch of the plurality of switches; and
discharging energy from the at least one solenoid to the power supply or another
solenoid of the solenoid actuator by at least one of
opening the at least one switch of the plurality of switches and
closing at least one other switch of the plurality of switches.
2. The method of claim 1, wherein providing at least one solenoid of the solenoid
coupled to the power supply through the plurality of switches comprises providing a latch
solenoid, an open solenoid, and a close solenoid coupled to the power supply through the
plurality of switches.
3. The method of claim 2, wherein providing the latch solenoid, the open solenoid,
and the close solenoid coupled to the power supply through the plurality of switches comprises
providing the latch solenoid, the open solenoid, and the close solenoid in series with each
terminal of the each of the latch solenoid, the open solenoid, and the close solenoid coupled to
the power supply through at least one of a switch of the plurality of switches or a diode.
18
4. The method of claim 3, wherein
energizing at least one solenoid of the solenoid actuator by closing at least one
switch of the plurality of switches comprises energizing the latch solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the latch solenoid and the open solenoid and
a switch between a second lead of the power supply and another terminal
of the latch solenoid; and
discharging energy from the at least one solenoid to the power supply or another
solenoid of the solenoid actuator by closing at least one other switch of the plurality of switches
comprises discharging energy from the latch solenoid by closing
a switch between the first lead of the power supply and the another
terminal of the latch solenoid and
a switch between the second lead of the power supply and the common
terminal between the latch solenoid and the open solenoid.
5. The method of claim 3, wherein
energizing at least one solenoid of the solenoid actuator by closing at least one
switch of the plurality of switches comprises energizing the open solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the latch solenoid and the open solenoid and
a switch between a second lead of the power supply and a common
terminal between the open solenoid and the close solenoid; and
discharging energy from the at least one solenoid to the power supply or another
solenoid of the solenoid actuator by closing at least one other switch of the plurality of switches
comprises discharging energy from the open solenoid by closing
a switch between the first lead of the power supply and a common
terminal between the latch solenoid and the open solenoid and
a switch between the second lead of the power supply and another
terminal of the close solenoid.
6. The method of claim 3, wherein
energizing at least one solenoid of the solenoid actuator by closing at least one
switch of the plurality of switches comprises energizing the close solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the open solenoid and the close solenoid and
a switch between a second lead of the power supply and another terminal
of the close solenoid; and
discharging energy from the at least one solenoid to the power supply or another
solenoid of the solenoid actuator by closing at least one other switch of the plurality of switches
comprises discharging energy from the close solenoid by closing
a switch between the first lead of the power supply and the another
terminal of the close solenoid and
a switch between the second lead of the power supply and the common
terminal between the open solenoid and the close solenoid.
7. The method of claim 2, wherein providing the latch solenoid, the open solenoid,
and the close solenoid coupled to the power supply through the plurality of switches comprises
providing the latch solenoid, the open solenoid, and the close solenoid in a delta configuration
with each terminal of the each of the latch solenoid, the open solenoid, and the close solenoid
coupled to the power supply through at least one of a switch of the plurality of switches or a
diode
8. The method of claim 7, wherein
energizing at least one solenoid of the solenoid actuator by closing at least one
switch of the plurality of switches comprises energizing the latch solenoid by closing
a first switch between a first lead of the power supply and a common
terminal between the latch solenoid and the open solenoid and
a second switch between a second lead of the power supply and another
terminal of the latch solenoid; and
discharging energy from the at least one solenoid to the power supply or another
solenoid of the solenoid actuator comprises discharging energy from the latch solenoid by
opening the first and second switches.
9. The method of claim 7, wherein
energizing at least one solenoid of the solenoid actuator by closing at least one
switch of the plurality of switches comprises energizing the open solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the latch solenoid and the open solenoid and
a switch between a second lead of the power supply and a common
terminal between the open solenoid and the close solenoid; and
discharging energy from the at least one solenoid to the power supply or another
solenoid of the solenoid actuator comprises discharging energy from the open solenoid by
closing a switch between the first lead of the power supply and the common terminal between
the open solenoid and the close solenoid.
10. The method of claim 7, wherein
energizing at least one solenoid of the solenoid actuator by closing at least one
switch of the plurality of switches comprises energizing the close solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the open solenoid and the close solenoid and
a switch between a second lead of the power supply and a common
terminal between the close solenoid and the latch solenoid; and
discharging energy from the at least one solenoid to the power supply or another
solenoid of the solenoid actuator comprises discharging energy from the close solenoid by
closing a switch between the second lead of the power supply and the common terminal between
the open solenoid and the close solenoid.
11. A system, comprising:
a solenoid actuator with at least one solenoid;
a power supply coupled to the at least one solenoid through a plurality of
switches;
a controller electrically coupled to the plurality of switches, the controller
comprising a processor and a memory device coupled to the process, the memory device
containing a set of instructions that, when executed by the processor cause the processor
to
energize at least one solenoid of the solenoid actuator by closing at least
one switch of the plurality of switches; and
discharge energy from the at least one solenoid to the power supply or
another solenoid of the solenoid actuator by at least one of
opening the at least one switch of the plurality of switches and
closing at least one other switch of the plurality of switches.
12. The system of claim 11, wherein the at least one solenoid of the solenoid actuator
comprises a latch solenoid, an open solenoid, and a close solenoid.
13. The system of claim 12, wherein the latch solenoid, the open solenoid, and the
close solenoid are electrically in series with each terminal of the each of the latch solenoid, the
open solenoid, and the close solenoid coupled to the power supply through at least one of a
switch of the plurality of switches or a diode.
14. The system of claim 13, wherein
the set of instructions that cause the processor to energize at least one solenoid of
the solenoid actuator by closing at least one switch of the plurality of switches further causes the
processor to energize the latch solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the latch solenoid and the open solenoid and
a switch between a second lead of the power supply and another terminal
of the latch solenoid; and
the set of instructions that cause the processor to discharge energy from the at
least one solenoid to the power supply or another solenoid of the solenoid actuator by closing at
least one other switch of the plurality of switches further causes the processor to discharge
energy from the latch solenoid by closing
a switch between the first lead of the power supply and the another
terminal of the latch solenoid and
a switch between the second lead of the power supply and the common
terminal between the latch solenoid and the open solenoid.
15. The system of claim 13, wherein
the set of instructions that cause the processor to energize at least one solenoid of
the solenoid actuator by closing at least one switch of the plurality of switches further causes the
processor to energize the open solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the latch solenoid and the open solenoid and
a switch between a second lead of the power supply and a common
terminal between the open solenoid and the close solenoid; and
the set of instructions that cause the processor to discharge energy from the at
least one solenoid to the power supply or another solenoid of the solenoid actuator by closing at
least one other switch of the plurality of switches further causes the processor to discharge
energy from the open solenoid by closing
a switch between the first lead of the power supply and a common
terminal between the latch solenoid and the open solenoid and
a switch between the second lead of the power supply and another
terminal of the close solenoid.
16. The system of claim 13, wherein
the set of instructions that cause the processor to energize at least one solenoid of
the solenoid actuator by closing at least one switch of the plurality of switches further causes the
processor to energize the close solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the open solenoid and the close solenoid and
a switch between a second lead of the power supply and another terminal
of the close solenoid; and
the set of instructions that cause the processor to discharge energy from the at
least one solenoid to the power supply or another solenoid of the solenoid actuator by closing at
least one other switch of the plurality of switches further causes the processor to discharge
energy from the close solenoid by closing
a switch between the first lead of the power supply and the another
terminal of the close solenoid and
a switch between the second lead of the power supply and the common
terminal between the open solenoid and the close solenoid.
17. The system of claim 12, wherein the latch solenoid, the open solenoid, and the
close solenoid are arranged in a delta configuration with each terminal of the each of the latch
solenoid, the open solenoid, and the close solenoid coupled to the power supply through at least
one of a switch of the plurality of switches or a diode.
18. The system of claim 17, wherein
the set of instructions that cause the processor to energize at least one solenoid of
the solenoid actuator by closing at least one switch of the plurality of switches further causes the
processor to energize the latch solenoid by closing
a first switch between a first lead of the power supply and a common
terminal between the latch solenoid and the open solenoid and
a second switch between a second lead of the power supply and another
terminal of the latch solenoid; and
the set of instructions that cause the processor to discharge energy from the at
least one solenoid to the power supply or another solenoid of the solenoid actuator further causes
the processor to discharge energy from the latch solenoid by opening the first and second
switches.
19. The system of claim 17, wherein
the set of instructions that cause the processor to energize at least one solenoid of
the solenoid actuator by closing at least one switch of the plurality of switches further causes the
processor to energize the open solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the latch solenoid and the open solenoid and
a switch between a second lead of the power supply and a common
terminal between the open solenoid and the close solenoid; and
the set of instructions that cause the processor to discharge energy from the at
least one solenoid to the power supply or another solenoid of the solenoid actuator further causes
the processor to discharge energy from the open solenoid by closing a switch between the first
lead of the power supply and the common terminal between the open solenoid and the close
solenoid.
20. The system of claim 17, wherein
the set of instructions that cause the processor to energize at least one solenoid of
the solenoid actuator by closing at least one switch of the plurality of switches further causes the
processor to energize the close solenoid by closing
a switch between a first lead of the power supply and a common terminal
between the open solenoid and the close solenoid and
a switch between a second lead of the power supply and a common
terminal between the close solenoid and the latch solenoid; and
the set of instructions that cause the processor to discharge energy from the at
least one solenoid to the power supply or another solenoid of the solenoid actuator further causes
the processor to discharge energy from the close solenoid by closing a switch between the
second lead of the power supply and the common terminal between the open solenoid and the
close solenoid.
21. The system of any one of claims 11-20, wherein the switches comprise solid state
switches.
22. The system of any one of claims 11-20, further comprising a housing of a
downhole telemetry system, wherein the solenoid actuator is coupled to the housing.