Understanding power concepts rev 0

1. UNDERSTANDING POWER
CONCEPTS
Vincent W. Wedelich P.E., MBA
Steven Sauer P.E., MEE
March 5, 2013

2. Power System Engineering
• During the last 50 years electrical engineering
has become very diversified.
• It is a much broader scope than ever before.
• In order to keep pace with emerging
technologies a need has been identified to
provide the fundamental knowledge of
electrical power engineering.

3. Electrical Power Engineering
• Manufacturing
– Generators, and motors
– Transformers
– Skidded packages (electro chlorination units, pump
packages, filtration units, process packages)
– MCC, SWGR, power houses
• Relay programming
• System studies
• Industrial Distribution systems (LV, MV)
• Transmission design (HV, EHV)

4. • VISUAL / MENTAL COMPREHENSION OF THE
COMPONENTS BASED ON PROJECT SINGLE LINE
AND SPECIFICATION.

5. Learning Objectives
• Close the
knowledge gap.
• Real world
examples.
• Check lists.
• Work problems.
• Survey the
industry.

6. Understanding Power Concepts
• Introduction
• AC/DC Basics
• Codes/Personal Safety
• Electrical Safety
• Grounding
• AC Induction Motors
• Maintenance of Motors

7. Understanding Power Concepts
• Motor Controllers
• Transformers
• Insulated Power Cables
• Rewinds‐Motors/Transformers
• Power Factor
• Overhead Distribution Systems
• Basic Operation of Generators

8. Understanding Power Concepts
• Batteries
• UPS systems
• Solar Panels
• Specific Power System Considerations
• Power Optimization
• Field Problems
• Misc. Articles/Reports

9. Introduction to
How this course
is put together.

10. Each module is broken down
into the following sections.
• Lecture on topic
• Examples
• Work Problem
• Class survey of what you
are seeing in the field.
There are 20 topics and six
2.5 hour sessions to cover this
material.

11. A little about
the
instructors.

12. Before starting a project you should know the answers to
the following questions.
• What is the nature and magnitude of the load?
• Where is the power coming from?
• How much will the electric power systems cost?
• What voltage levels should be selected for the
plant primary system and secondary system?
• What circuit arrangement is best suited, ie;
radial, secondary selective, or secondary
network?
• What size substations are most economical?
• Secondary distribution.
• Combined light and power?
• Are voltage regulating means required?
• Short‐circuit protection?
• Grounding.
• Overcurrent protection?
• Is the lightning protection adequate?
• Power factor correction?
• Types of Lights required.

13. • AC/DC Basics• AC/DC Basics1
• Codes/Personal Safety• Codes/Personal Safety2
• Electrical Safety• Electrical Safety3
• Grounding• Grounding4
Course Overview (modules 1‐4)

14. AC/DC BASICS

16. Basic Electricity for Industry
• Ohm’s law
• Impedance
• Power (kW)
• Reactive power (kVAR)
• Apparent power (kVA)
• Power factor (cos theta)
• Efficiency
• Work problems.
• Survey the industry.

17. Ohm’s Law
• E: Electromotive force or
Voltage; Volts, V
• I: Electric Current;
Amperes, A
• R: Resistance of heater;
Ohms, omega
• P: Power; watts
• Example solving
resistance heater
element connected to
the terminal of an AC
generator.

18. http://www.chromalox.com/productca
talog/Component+Technologies/Strip+
and+Ring+Heaters/product‐family‐
router.aspx?f=64

19. http://www.chromalox.com/resource‐center/calculators/ohms‐law.aspx#

21. Let’s consider three resistive
elements. (series circuit)

22. Equivalent Circuit

23. Parallel Circuit

24. Parallel Circuit

27. Networks are electrical
transmission/distribution systems

28. Cyclic Voltage and Current

30. Sinusoidal Voltage and Current

32. Cyclic Voltage and Current

33. Basic Electrical Quantities

34. Basic Electrical Formulas

35. Decimal Multiples and Submultiples

36. Current in phase with voltage

37. AC Voltage and Current in a resistance

38. Current lagging voltage by 30 deg.

39. AC Voltage and current in an inductive
reactance.

40. Inductive Equipment Used in Industry
• Transformers
• Solenoids
• Variable Transformers
• Relays
• Fluorescent light
ballasts
• Motors

41. AC Voltage and Current in a capacitive
reactance

42. Capacitor Equipment Used in Industry

43. Impedance of an ac circuit

44. Parallel R‐L circuit

45. Parallel R,L,C circuit

46. Impedance formula series connected
elements

47. Impedance Formula Parallel‐
Connected Elements

48. Power in AC circuits and systems
(inductive)

49. Power in AC circuits and systems
(capacitive)

50. Typical users of power and their
characteristics.

51. Power Factor or load and supply

52. Power and Power Factor in an
induction load

53. Power Capacitor connected to Motor

54. Power Capacitor connected to Motor

55. Power Capacitor connected to Motor

56. Generation of three phase voltage

57. Line voltages and line to neutral
voltages

58. Voltages generated by a 3‐phase 440
volt AC generator.

59. Line currents in a balanced 3‐phase
circuit

60. Instantaneous currents in a balanced
3‐phase circuit

61. Delta and Wye connected loads

62. Current and
voltage in a
wye
connection

63. Current and
voltage in a
delta
connection

64. http://www.chromalox.com/productca
talog/Component+Technologies/Strip+
and+Ring+Heaters/product‐family‐
router.aspx?f=64

65. Three resistors are connected in a
wye across a 440V 3‐phase line. If
they dissipated a total of 6000 W, or
6kW, calculate:
1) Calculate the
line current.
2) Calculate the
resistor
values.

67. A 4kV 3‐phase line carries a line
current of 90A. The power factor is
0.85 lagging, and the load is
connected in delta.
Calculate:
1) The impedance of
the load, per phase.
2) The reactive power,
per phase.

69. Phase sequence

70. Measuring Electrical Power

71. A single phase transformer 7200‐
240/120 volts, 50kVA.
1) Solve the current low and high side of transformer.
2) If a 2 ohm resistor is connect between a and b, 3 ohm resistor connected from b
to N. What is the total kVA load on the transformer and what is the current
drawn from the primary line (7200 volts)?
3) If this transformer is tested for polarity by connecting a jumper to H1 and X3 and
applying 240volts to terminals H1 and X1, based on the terminal markings for this
transformer as shown in the figure.
4) An impedance test is run on this transformer. The nameplate impedance is 3.5%.
What voltage, when applied to the terminals of H1 and H2 with terminals X1 and
X3 short‐circuited should give rated current in the H1, H2 windings?

72. Does the equipment used to transmit the power to the load
have a large impact on the power factor?
Typical equipment would be cables and transformers
• These components do not dictate power factor,
but only have a small effect on it under normal
steady state conditions.
• Under fault conditions their effect is very large.

73. What is short circuit current?
• Uncontrolled flow of current.
• Due to insulation failure.

74. Cost of Power

75. Main equipment used:

76. Main equipment used:

77. Main equipment used:

78. Main equipment used:

79. Main equipment used:

80. Main equipment used:

81. Main equipment used:

82. Main equipment used:

83. Main equipment used:

84. General Causes of failure of electrical
equipment.

85. • AC/DC Basics• AC/DC Basics1
• Codes/Personal Safety• Codes/Personal Safety2
• Electrical Safety• Electrical Safety3
• Grounding• Grounding4
Course Overview (modules 1‐4)

86. CODES AND
PERSONAL SAFETY

87. Electrical Codes
• NFPA 70 (National Electrical Code)
• OSHA (Occupational Safety and Health Act)
• API RP‐14F
• API RP‐500
• NFPA 70E
• NESC (The National Electrical Safety Code)

88. National Electrical Code

89. API RP‐14F

90. API RP‐500

98. • AC/DC Basics• AC/DC Basics1
• Codes/Personal Safety• Codes/Personal Safety2
• Electrical Safety• Electrical Safety3
• Grounding• Grounding4
Course Overview (modules 1‐4)

99. ELECTRICAL SAFETY

100. • AC/DC Basics• AC/DC Basics1
• Codes/Personal Safety• Codes/Personal Safety2
• Electrical Safety• Electrical Safety3
• Grounding• Grounding4
Course Overview (modules 1‐4)

101. GROUNDING

102. New Work
The technology learning curve
New
Employee
1 yr 2 yr 3 yr

103. Who’s Who
Lead Contact information
Jim Jim@company.com
Dee Dee@gcompany.com
Mavis Mavis@company.com
Doug Doug@company.com

104. Time Spent
Projects Worked On
Get Familiar
Achieve
Mastery
Working Toward Mastery
Get
Experienced

105. Doing Your Best Work
• Working from home
• Working offsite
• Technology
requirements

106. Case Study
• Jeremy
– His first day
– Mistakes made
– Successes achieved
– The moral of the story

107. Discussion
• What we can learn
from Jeremy
• Best practices
• Take‐aways

108. Summary
• Define your challenges
– Technological as well as personal
• Set realistic expectation
– Mastery is not achieved overnight
• Keep your eye on the goal
– Mentorship programs

109. Resources
• <Intranet site text here>
<hyperlink here>
• <Additional reading material text here>
<hyperlink here>
• This slide deck and related resources:
<hyperlink here>

110. QUESTIONS?

111. APPENDIX