downhole esp gauge with motor diagnostics · •operate esp at the best efficiency and lowest cost...

Copyright 2018 Baker Hughes, a GE company, LLC (“BHGE”). All rights reserved. The information contained in this document is company confidential and proprietary property of BHGE and its affiliates. It is to be used only for the benefit of BHGE and may not be distributed, transmitted, reproduced, altered, or used for any purpose without the express written consent of BHGE.

Downhole ESP Gauge with Motor DiagnosticsNew Downhole electrical measurements optimising efficiency & output

EuALF 2018 European Artificial Lift Forum13-14 June 2018, AECC, Aberdeen, UK

June 27, 2018

Copyright 2018 Baker Hughes, a GE company, LLC (“BHGE”). All rights reserved.

Gauge history

DOWNHOLE GAUGE DEVELOPMENT

2018201720142011200820052002199919961993

First downhole pressure and temperature gauge

1994First multi-parameter ESP gauge

2007Distributed pressure, temperature, vibration measurements across the ESP

2012First ground fault immune ESP gauge 2016

First downhole ESP gauge with MD system


• Gauge connected to the motor WYE point

• Gauge power and data superimposed onto the 3phase ESP electrical circuit

• Extracted at surface via a electrical choke

• No separate TEC lines to surface

ESP gauges are typically “Comms on Power”

June 27, 2018 3


MEASURED PARAMETERS

The latest ESP gauge parameters

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Intelligent Parameters: for advanced well and pump analysis, diagnosis and optimisation

Predictive Parameters: for preventative maintenance and effective workover management

Primary Parameters: for essential pump and well surveillance and protection

* calculated parameter

1993 1996 1999 2002 2005 2008 2011 2014

intake pressure

well temperature

discharge pressure

motor oil / winding temperature

vibration

current leakage

bottom hole flowing pressure*

fluid level above pump*

wellhead pressure

total liquid flow rate*

water cut*

real time pump curve with operating point*

phase ABC voltage & imbalance

cable insulation & fault resistance*

cable fault severity*

cable fault depth*

bad phase*

wye point voltage (downhole)

motor frequency

slip rate

power factor

torque & hp

downhole volts & amps

motor efficiency

shaft rotation direction

2017


• Connects to the motor windings in the same way as a conventional ESP gauge

• New electrical measurements added to the standard pressure, temperature and vibration parameters

• All data transferred via ESP cable to surface

• Conventional surface logger displays/logs parameters

ESP gauge with motor diagnostics

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PACKAGING

Looks like a regular ESP comms on power gauge

E-series ESP Gauge with Motor DiagnosticsStandard Zenith E-series ESP Gauge


MEASURED PARAMETERS

Along with Pi, Pd, Ti, Tm, Vx and Vz, the gauge provides:

Zenith E-Series ESP gauge with motor diagnostics

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Measurement Impact

Shaft RPM Lift Performance / power / production

Slip rate Lift Performance / power / production

True power factor Power

Torque Lift Performance

Motor HP Power

Real-time cable insulation Lift Diagnostics

Imbalance indicator Lift Diagnostics

Motor efficiency Lift Performance / power

Shaft rotation direction Lift Diagnostics / production


OPTIMISING POWER USAGE


TRADITIONAL PARAMETERS

• Pressures

• Temperatures

• Vibration

Power optimisation

June 27, 2018 8

NEW ELECTRICAL DATA

• Downhole wye-point

• Waveform analysis

• Surface wye-point

• Waveform analysis

• Volts, Amps, Hz

OUTPUT PARAMETERS

• Slip rate

• Power factor

• True motor horse power

• Efficiency

• Torque

• Imbalance

• Rotation direction

Replaces calculated parameters with real time measured data➔ allowing more accurate and confident ESP optimisation

Fully compatible with intelligent well and field optimisation software➔ optimise power vs barrels produced considering both production and ESP power usage


SOURCES OF POWER QUALITY ISSUES

Customer power quality challenges

June 27, 2018 9

Effect of power quality on ESP operations:

• Operating Expense

• Downtime

• Equipment Run Life

24%

19%

13%5%

28%

11%

Voltage Dips Short Interruptions Long Interrruptions

Harmonics Transients & Surges Other PQ Problems

Source:- ResearchGate


BENEFITS OF KNOWING YOUR TRUE SURFACE AND DOWNHOLE POWER FACTOR

The impact of insight into true power factor

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• Reduction of electricity bills

• Extra KVA available from existing supply

• Reduction of losses and voltage drops

• Extended equipment life

• Environmental

– Reduced consumption / improved efficiency

– Less emissions / fossil fuel depletion

displacement

distortion


THE RELATION BETWEEN FULL LOAD AND TORQUE / HP

Motor load – why is measured torque and horsepower useful?

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• Ideally you can vary motor load from 0 – 100% by changing the frequency from 0 – 60Hz, this is in an ideal motor and ideal design.

• To run a motor efficiently it is beneficial to know torque, HP and load.

• A VSD does not have a direct measurement of downhole torque, HP or load at the motor (a VSD calculates these parameters based on correct input of motor vs surface electrical data)

• The motor diagnostics gauge is agnostic of input data and highlights when 100% load is achieved in real time

• Load and torque can be used to protect the motor and run at optimum power consumption


CASE STUDY: Motor load optimization

June 27, 2018

• The ESP was designed to reach 100% load and 100% HP at 60Hz.

• However the gauge identified that the motor reached 100% load at around 48Hz.

• It was (later) advised that at this point the motor was re-rated to 150% by adjusting tappings and “adjusting” VSD nameplate value settings

• Full load was detected again by the gauge at ~57Hz.

• The motor diagnostics gauge advises exactly when 100% HP is achieved so user can correct tappings to operate at best motor efficiency vs load

70

75

80

85

90

95

100

105

45 47 49 51 53 55 57 59 61 63

%

FREQUENCY

Motor Monitoring: Torque & HP

HPi prcnt Tq prcnt

Nameplate reference detected

Full load/Saturation detected

35

40

45

50

55

60

65

45 50 55 60 65

Am

ps

FREQUENCY

Downhole Amps (ESP Drive)

Downhole Amps

Current drawn by the motor increasingBut power is wasted


CASE STUDY: Motor load

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At ~120% of motor rated load (~120% of original nameplate) extra power supplied from increasing frequency is wasted

SAME PRODUCTION @ LESS POWER COST

0%

20%

40%

60%

80%

100%

120%

140%

45 47 49 51 53 55 57 59 61 63

load

FREQ - HZ

Max load reached

Motor saturated, no increase in the motor load after 57Hz approx.

Traditional method is to calculate the load from Volts and amps.

The new gauge measures load in real time



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MEASURED MOTOR LOAD (GAUGE) VS. CALCULATED MOTOR AMPS (VSD)

30

35

40

45

50

55

60

65

80%

85%

90%

95%

100%

105%

110%

115%

120%

125%

45Hz 47Hz 49Hz 51Hz 53Hz 55Hz 57Hz 59Hz 61Hz 63Hz

Load Downhole Amps

AM

PS

Max load

Load measured by the MD DHG

Current draw

POWER WASTED



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MOTOR EFFICIENCY VS VSD CALCULATED DOWNHOLE AMPS

76%

78%

80%

82%

84%

86%

88%

90%

0

10

20

30

40

50

60

70

45 47 49 51 53 55 57 59 61 63Hz

Downhole Amps eff

AM

PS

Max load measured by the MD DHG


• Motor data suggests that by changing Volt/Hz ratio from current settings to 60 Hz (e.g. volts which are supplied at 63Hz now to be supplied at 58 – 60Hz) should deliver

Potential saving of 9% - 13% on power cost with the same production

• In this case the VSD tripped many times after exceeding the suggested maximum operating point of 57Hz .

• Due to long log rate of VSD data — poor user input — trips were not always detected in VSD amperage log leading to extended downtime

CASE STUDY: Available power saving

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~150% SUDDEN INCREASE IN LOAD DETECTED

Exceeding maximum motor torque, in this case 350%, may shear the shaft or cause permanent damage – if not controlled or rectified.

CASE STUDY: Motor performance diagnostics

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0%

100%

200%

300%

400%

0 1 2 3 4 5 6 7 8

Load/ Torque

slip/load stressLoad Torque

Trip

Caused huge steps of motor load and torque

0

20

40

60

80

0 1 2 3 4 5 6 7 8

Frequency1 minute

Within 1 minute, frequency drops from 60Hz to 35Hz & returns to 60


Increased stress indicated by the DHG, while ∆P and DH amps did not change.

The ESP tripped for electrical motor failure.

CASE STUDY: Motor failure prediction

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%

# of point – over 13 hours

Coms lost/ ESP tripped


• Motor diagnostics gauge immediately shows motor direction without having to wait for fluid to surface

• Detects stuck pumps

• Forward/reverse configurable for pump manufacturer

Optimising production

June 27, 2018 19


MEASURING TRUE BACKSPIN DOWNHOLE

• Zenith gauge is capable of detecting backspin, ruling out risk involved in measuring voltage manually & perhaps eliminating need for a backspin relay.

• Backspin info can be vital during RIH ensuring kill fluid rate is within safe range to the ESP stages.

• Pi, Pd readings will not necessarily indicate backspin in all cases.

• Graph is an example of backspin logs taken at intervals during RIH.

Case study data: Backspin

June 27, 2018 20

0

5

10

15

20

25

30

35

0 10 20 30 40 50

Kill fluid (Freq)

SF Hz


Conclusion

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BENEFITS


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• Replaces inaccurate surface calculations

• Enables accurate electrical performance monitoring

• Run equipment at actual optimum points against load

System adjustments are made based on measured not estimated values ensuring truly efficient, safeguarded ESP operations.

Motor Shaft RPM

Slip Rate

Power Factor

Torque & HP

Imbalance Indicator

ShaftDirection

Motor Efficiency


CONCLUSION

The Zenith E-Series Gauge with Motor Diagnostics provides real-time power analysis enabling operator to:

• Monitor motor performance for informed decision-making

• Operate ESP at the best efficiency and lowest cost

• Place less strain on equipment to enhance runlife

• Quickly know pump is spinning the correct way at start up

• Optimize production vs power consumption


June 27, 2018 23

downhole esp gauge with motor diagnostics · •operate esp at the best efficiency and lowest cost...

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