This document discusses wide area measurement and monitoring of power systems using phasor measurement units (PMUs). It begins with an introduction to the increasing demand for electricity and the need to improve reliability, efficiency, and quality of supply. Reports are cited showing that many power disturbances are caused by protection failures or false trips. The document then compares classical protection schemes with wide area measurement and control using PMUs, which provide accurate dynamic measurements for fast, coordinated actions. Applications of PMUs discussed include transmission line protection, system monitoring, modeling verification, and fault analysis. Adaptive relaying is also described as using PMUs to adjust protection settings based on system conditions.

1. Wide area measurement and
monitoring of power system

2. Objectives:
• present scenario of electric supply system.
•comparison between current protection scheme and wide area
measurement and control system.
•General set up wide area measurement system
•PMU and it’s applications

3. Introduction
• electricity- backbone of every country
• Demand increasing day by day
• Electrical Utilities are undergoing a
period fundamental changes
• Due to competition, the aim at
• Improving economic efficiency
• Reliability of the supply
• Quality of the supply

4. Reports
• NERC report showed that 63% major
disturbances are protection related
• CIGRE study found that 27% of
buck power disturbances resulted
from false trips
So generation, transmission and distribution must
be adequately controlled and protected.

5. Essential for Protection
Dependability: measures of the ability to
correctly clear a fault.
 Security: measure of tendency not to trip
incorrectly.

6. Wide Area Measurement Vs Classical
Protection and SCADA/EMS Protection
• SCADA/EMS
•Static View
•Action initiated by Long-term Phenomena
(Simulated and Off-line)
• Classical Protection
• Direct local actions by on-line status
information
• Wide area Monitoring
& Control
• accurate measurements
•loadability monitoring
• fast control of network
controllers
• Wide Area Protection
• dynamic view
• all kinds of stability
• cascaded outages
• fast, optimised & co-
ordinated action
static
dynamic
coordinated
Un-coordinated

7. Wide Area Measurement Vs Classical Protection
and SCADA/EMS Protection

8. Advantages of the Wide Area
Measurement
• Better use of installed equipment
• Increasing power transmission capability
• Blackout prevention
• Reduced impact of disturbances

9. General set up of Wide Area
Measurement System

10. Historical development of
synchronized phasor measurement
•Invention of SCDR
•Development of prototype PMU
•Commercial manufacture of PMUs
•Field installation of PMU for Wide Area
measurement

11. Phasor Measurement System
Data stream to
other application
Phasor data
concentrator
PMU
PMU
PMU
PMU
PMU
Phasor data
concentrator
Measurement
from other utility
PDC data exchange
Monitor/record
Analysis Matlab
or other

12. Phasor Measurement Process
DFT
DFT
DFT
Symmetrical
Component
Transformation
Frequency
& rate of
change of
frequency
Disturbance &
Transient Detectors
Trigger
Flag
F
Phasor

13. Application of PMU
• Transmission Line Protection and Adaptive Relaying
• Power System Monitoring & Emergency Control
• Transmission and Generation Modeling Verification
• Fault Analysis and Disturbance Recording

14. Adaptive Relaying
Definition:
Adaptive relaying is a protection philosophy which permits and
seeks to make adjustments to various protection functions in
order to make them more attuned to prevailing power system
conditions.
 Out-of-step relays are particularly suited for the application of
adaptive techniques.
 Adaptive out-of-step relays are designed to recognize changes
in the power system that may occurred and adapt the setting
accordingly.

15. Setting of the Adaptive Relaying
 During the stable transient
Block:YY trajectory
 During the un-stable transient
Trip: ZZ trajectory
R
Z
Y Y
X
Z

16. Setting of the Adaptive Relaying
y
z z
X
y
During the stable transient
Block:YY trajectory
 During the un-stable transient
Trip: ZZ trajectory

17. PMU as indicator of dynamic performance of
system
Transmission line protection:-

18. PMU as indicator of dynamic performance
of system

19. Conclusion :
•Fault and disturbance monitoring application would
be benefited by using wide area measurement scheme
• DFT and SDFT are most powerful tool for extraction of phasor
•Angle between Positive sequence synchronised voltages is
directly represent the stability of the system.

20. Thank You