This document discusses reactive power and voltage control in electrical power systems. It defines real and reactive power and explains that reactive power is needed to maintain adequate voltages throughout transmission and distribution systems. Several methods of providing reactive power are described, including synchronous condensers, capacitors, static VAR compensators, and distributed generation. The document also discusses different types of voltage and VAR control and compares characteristics of various reactive power sources.

1. UNDER THE GUIDANCE OF :
MR D.MOHAN ROA (ASST.PROF)
TEAM DETAILS
1 V.DHARMATEJAREDDY(11-245)
2 T.BHARATH KUMAR(10-217)
3 K .SINDHU REDDY(11-11-221)
4 B.SUSHMA (12-203)

2. 1. DEFINATIONS OF VARIOUS POWERS
 POWER : POWER can be defined as the rate
of flow of energy at a given point of circuit
 REAL POWER :The portion of power that
,averaged over a complete cycle of the ac
waveform ,results in net transfer of energy
in one direction is known as real power
 Reactive power : The portion of power due
to stored energy , which returns to the
source in each cycle is known as reactive
power

4.  Voltage control in an electrical power system
is very important for proper operation for
electrical power equipment to prevent
damage
 Decreasing reactive power causing voltage to
fall while increasing it causing voltage to rise
 When reactive power supply lower voltage
,as voltage drops current must increase to
maintain power supplied , causing system to
consume more reactive power which causes
cascading failures

5.  If the voltage drops too low ,some generators
will disconnect automatically to protect
themselves ,these will cause additional
elements of trip , leading further reduction
In voltage and loss of the load
 Reactive power is essential to move active
power through the transmission and
distribution system to the consumer

6.  Three reasons :
 1.It must maintain adequate voltages
throughout the transmission and distribution
system for both current and contingency
conditions
 It seeks to maintain congestion of real power
flows
 It seeks to minimize real power losses

7.  Voltages are controlled by providing
sufficient reactive power control margin to
supply needs through
 1.shunt capacitor and reactor compensations
 2.dynamic compensation
 3. proper voltage schedule of generation

8.  Reactive power does not travel very far
 Usually necessary to produce it close to the
location where it is needed
 A supplier/source close to the location of the
need is In a much better position to provide
reactive power versus one that is located far
from the location of the need
 Reactive power supplies are closely tied to
the availability to deliver real or active
power

9.  1.Generation
 2.synchronous condensors
 3. capacitors & inductors
 4.static var compensators ( svcs )
 5.distributed generation
 6.transmission side

10.  Power flow control
 Increase of transmission capability
 Voltage control
 Reactive power compensation
 Stability improvement
 Power conditioning
 Flicker mitigation
 Interconnection of renewable and distributed
generation and storages

11.  Static VAR compensator
 Static compensator(STATCOM)
 Series compensation
 Thyristor controlled series CAPACITORS
 SSSC

12.  1.STATIC VS DYNAMIC VOLTAGE SUPPORT
 2.REACTIVE RESERVES DURING VARYING
OPERATING CONDITIONS
 3.VOLTAGE COORDINATION
 PLANT VOLTAGE SCHEDULE
 TEANSFORMER TAP SETTINGS
 REACTIVE DEVICE SETTINGS
 LOAD SHEDDING SCHEMES
 VOLTAGE AND REACTIVE POWER CONTROL

13.  Voltage regulator
 VAR control
 Volt and VAR control type 1 –stand alone
controllers
 Smart disrtibution voltage control
 Volt and VAR control type 2 –integrated volt
and VAR control(IVVC)
 VOLT and VAR CONTROL TYPE 3- INTEGRATED
VVO

14.  SYNCHRONOUS CONDENSER
I. ACCURACY---GOOD
II. CONTROL FLEXIBILITY---GOOD
III. CONTROL---CONTINOUS
IV. RESPONSE TIME—SLOW
V. HARMONICS----VERY GOOD
VI. LOSSES—MODERATE
VII. COST---HIGH

15. 1. ACCURACY------ VERY GOOD
2. FLEXIBILITY-----GOOD
3. CONTROL-----CONTINOUS
4. RESPONSE TIME----FAST
5. HARMONICS----VERY HIGH
6. LOSSES----GOOD
7. COST --- MODERATE

16.  ACCURACY--- EXCELLENT
 FLEXIBILITY----EXCELLENT
 RESPONSE TIME---VERY FAST
 HARMONICS-------GOOD
 LOSSES-----VERY GOOD
 COST-----LOW