The CardBuild® Control System continuously evaluates well position to
effectively harness the power of the regenerative VFD.
The AC Motor is controlled to provide large amounts of
braking torque when slowing is required, which allows the pump to run at higher
overall SPM, and slow down at appropriate points.
Higher Reliability of Surface Equipment
Speeds at reversals on Rotoflex units are controlled. Automatic adjustment
maintains safe speeds when well conditions, such as fluid level, change.
The CardBuild® Control System reduces speed automatically if any of the
electrical components reach warning temperature and returns to full speed when
operating temperature decreases.
A shallow rod part or polished rod part can be a significant potential
problem, especially for Rotoflex pumping units. The stored energy in a
free-falling weight stack when not properly controlled can result in significant
mechanical damage, major repair expense and extended downtime. The CardBuild®
Control System is designed to detect a free-falling weight stack and intervene
to protect the pumping unit. While we do not guarantee to eliminate damage in
all circumstances, this system has been successful in preventing mechanical
damage due to polished rod failure during field operations (in 100% of failures experienced to date).
Gearbox torque limit protection setting gives gearbox protection
even heavy load conditions.
Higher Reliability of Down-hole Equipment
Surface Dynagraph cards can be improved by eliminating rapid tension
changes. The use of “Tension Control” results in the following:
Rod Float in heavy oil is automatically regulated.
Maximum tension is lowered by as much as 10%.
Minimum tension is increased by as much as 30%.
Rod compression is effectively managed, even on wells that pump off or wells
with significant gas interference. This is done by maintaining relatively high
tension on the down stroke.
Fluid pound is effectively managed.
Simple, Flexible and Powerful Operator Interface
A single interface device is used for set up of all aspects of control.
Control comes with standard settings for different pumping units (i.e. Mark II, Rotoflex, Conventional, Air-Balance, etc...).
Designed for easy interface with Lufkin and Weatherford Pump-Off Controllers.
Set up is extremely flexible for operators who wish to “fine-tune” operation.
Extremely Low Harmonic Current Distortion
Transistorized converter replaces diode bridge converter and its associated low
order harmonics.
Large LCL filter limits high frequency noise from transistors and provides
added isolation between drive and power system.
KVAR Production
Our largest unit, the RWC1200 can produce as much as 80 kvar per well.
Distributed kvar production increases overall field power factor and can
decrease current in medium voltage feeder circuits.
Telemetry Options
MODBUS TCP and MODBUS RTU are available options.
Packaging
The panel used for the RWC Series has two compartments. Electronics are housed
in a rain tight, dust tight section. The VFD is side-mounted in an easily
removable shroud. Should a failure occur, the VFD/shroud assembly can be
replaced in less than 30 minutes. This drastically reduces downtime and
eliminates troubleshooting in the field. We do the troubleshooting at our
facility.
