sachu technologies team provides comprehensive power quality analysis and can implement measures to bring power quality to acceptable standards. Improving power quality can bring significant financial benefits. Poor power quality can damage sensitive equipment. Poor power quality can lower productivity and also drive up energy costs. Poor power quality can cause increased expenditure on electrical assets when plant or building expansion is necessary. Poor power quality can impair the safety of electrical installations.

1. Power Quality Analysis and
Harmonics Study
SERVICE PROVIDERS BY SACHU
TECHNOLOGIES
MIG 519,RK Nilayam,Phase III,KPHB,Kukatpally,Hyderabad-85
Cell:09493013535,Email:info@sachu.in, Web site: www.sachu.in

2.  Sachu Technologies conducts power quality analysis, Harmonics
monitoring & measurement services for complete facility power
systems or for individual loads using state of the art circuit analysis
and simulation software in PAN India basis in order to prevent
electrical devices from any faults & damages.
 Sachu Technologies also offers Thermography Survey, Electrical
Safety Audit, Energy Audit, Vibration Monitoring Analysis,Earth
Audit,Lighting Survey and Thermovision Scanning for Transmission
line Towers, Solar PV and Insulation resistance measurement all
over India including Hyderabad, Bangalore,Noida, Chennai,
Coimbatore, Kolkata, Visakhapatnam, Nagpur, Delhi, Pune, Mumbai,
Ahmedabad, Guwahati, Indore, Surat, Baroda, Kanpur, Kochi,
Bhubaneswar, Goa, Lucknow, Vijayawada, Nellore and other cities as
a part of Preventive and predictive maintenance programs
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Sachu Technologies profile

3. WHAT IS POWER QUALITY ANALYSIS
 Power quality analysis is exactly analyzing the quality of power
supply.Power quality analysis is rewarding for electric utilities since it
enables continuous monitoring, early excursion detection, root cause
analysis, and timely corrective actions improving overall grid reliability.
 Power quality is also of interest for major energy consumers to minimize
amount of power quality events and avoid expensive equipment failures.
 Power quality is a multi-dimensional and complex measure, especially as it
applies to AC power circuits. PQ encompasses voltage, current, power
factor and frequency spectrum magnitudes. It can involve electromagnetic
field measures. Sudden or gradual changes in any of these measures have
a big impact on power quality. PQ is really a comparison of the actual to
the ideal or desired values of each of the characteristics of electrical
power. Unlike current or power, which are measured in amperes and watts
there is no scoring or measurement unit for PQ. Consequently, terms
associated with power quality refer to the gaps or anomalies between the
actual and desired values. Desired attributes of PQ are therefore negative
terms; no dips, no spikes, no sags, no surges, no outages etc.
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4. Why Measure Power Quality?
 Power Quality (PQ) refers to the reliable delivery of electrical
energy in a form that enables electrical equipment to operate
properly. When dips and swells, spikes, surges, momentary
outages, sags or other disturbances occur – computers and other
electrically powered equipment may malfunction, fail prematurely
or shut down unexpectedly. Many facilities simply cannot accept
these consequences. Consider hospitals, banks, data
communications centers, manufacturing and other facilities that
rely on smooth, reliable power for operations. The consequences
of an unplanned outage can cost thousands of dollars each minute
or result in unsafe conditions or other serious problems unsafe
conditions or other serious problems.
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5. Reference standards used for
Power Quality Study
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6. Power Quality Audit Services in India
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7. Harmonic Study Services in India
power-quality-Analysis Instruments
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8. Power Quality related curves and shapes
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9. Power quality Analysers shall be used for
work in the field
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10. .
Point of common coupling (PCC)
 The orthodox electric power distribution systems used to be
generally radial and direction of flow of power was often from grid
towards consumer. Sometimes, the transmission of power generated
from newly set small power stations by using transmission network
is not feasible due to the transmission losses, service cost on
transmission lines and other related issues. That is why, in many
cases, small power stations are connected directly to the local
distribution network. These small power stations inject active and
reactive power to the existing network, badly disturbing the flow of
power hence injecting harmonics in the system at the point of
common coupling (PCC).
 This harmonic injection at PCC due to a direct grid-connection of
small power stations to the existing large electric power systems is
identified. Also, the impact of harmonic incursion by these small
generation units is analyzed using a straightforward and an
effortless method. This simulation based method uses power system
components simplified to basic inductive and capacitive elements
and can be very helpful for a fast assessment of harmonic incursion
at PCC if extended to the practical large inter-connected electric
power systems.

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11. Total Harmonic Distortion (THD)
 Total harmonic distortion (THD) is the cumulative degree of
distortion within an electrical current compared to the ideal.
Most household electrical systems draw linear loads. On a
linear current sine curve, the peaks and troughs are smooth,
even, and sinusoidal. Some distortion can take effect in
residential circuits but not enough to cause significant
efficiency issues.
 Total harmonic distortion is inversely proportional to power
factor. If a given load has a higher power factor, its THD factor
will be lower and the system will be more efficient. Fortunately,
most power utilities adhere to standards that require supply
voltage to have a relatively low THD factor; the power entering
your facility is relatively linear
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12. What is Total Harmonic Distortion
 Total harmonic distortion is a complex and often confusing concept to grasp.
However, when broken down into the basic definitions of harmonics and distortion,
it becomes much easier to understand.
Now imagine that this load is going to take on one of two basic types: linear or
nonlinear. The type of load is going to affect the power quality of the system. This
is due to the current draw of each type of load. Linear loads draw current that is
sinusoidal in nature so they generally do not distort the waveform (Figure 2). Most
household appliances are categorized as linear loads. Non-linear loads, however,
can draw current that is not perfectly sinusoidal . Since the current waveform
deviates from a sine wave, voltage waveform distortions are created.
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13. Importance of Mitigating THD
 While there is no national standard dictating THD limits on
systems, there are recommended values for acceptable
harmonic distortion. IEEE Std 519,RECOMMENDED PRACTICES
AND REQUIREMENTS FOR HARMONIC CONTROL IN ELECTRICAL
POWER SYSTEMS provides suggested harmonic values for power
systems.
 The limits on voltage harmonics are thus set at 5% for THD and
3% for any single harmonic. It is important to note that the
suggestions and values given in this standard are purely
voluntary. However, keeping low THD values on a system will
further ensure proper operation of equipment and a longer
equipment life span.
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14. Reactive Power
 Reactive loads such as inductors and capacitors dissipate
zero power, yet the fact that they drop voltage and draw
current gives the deceptive impression that they actually do
dissipate power. This “phantom power” is called reactive
power, and it is measured in a unit called Volt-Amps-Reactive
(VAR), rather than watts. The mathematical symbol for
reactive power is (unfortunately) the capital letter Q.
 The actual amount of power being used, or dissipated, in a
circuit is called true power, and it is measured in watts
(symbolized by the capital letter P, as always).
 The combination of reactive power and true power is called
apparent power, and it is the product of a circuit’s voltage
and current, without reference to phase angle. Apparent
power is measured in the unit of Volt-Amps (VA) and is
symbolized by the capital letter S.
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15. Need of Reactive Power Compensation
 Electrical utility may have to take the power factors of these industrial
customers into account paying a penalty if their power factor drops below a
prescribed value because it costs the utility companies more to supply
industrial customers since larger conductors, larger transformers, larger
switchgear, etc, is required to handle the larger currents.
 Generally, for a load with a power factor of less than 0.95 more reactive
power is required. For a load with a power factor value higher than 0.95 is
considered good as the power is being consumed more effectively, and a
load with a power factor of 1.0 or unity is considered perfect and does not
use any reactive power.
 Active or real power is a result of a circuit containing resistive components
only, while reactive power results from a circuit containing either capacitive
and inductive components. Almost all AC circuits will contain a combination
of these R, L and C components.
 To avoid reactive power charges, is to install power factor correction
capacitors
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16. Reactive Power factor compensation solutions
 Reactive Power need and no harmonics-----Capacitor Banks
 Reactive Power need and no distortion even if Harmonics are present
------Detuned Filters
 Reactive Power need and distortion problems---Tuned Filters
 Reactive Power need and strong distortion problems such as fast
voltage fluctuations ----- SVC’s
A static VAR compensator (SVC) is a set of electrical devices for providing fast-
acting reactive power used in Transmission line Networks
Reducing reactive power to help improve the power factor and system
efficiency is a good thing, one of the disadvantages of reactive power is that a
sufficient quantity of it is required to control the voltage and overcome the
losses. This is because if the electrical network voltage is not high enough,
active power cannot be supplied. But having too much reactive power flowing
around in the network can cause excess heating (I2*R losses) and undesirable
voltage drops and loss of power
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17. LV Capacitors, HV Capacitors,
Capacitor Banks,Detuned Filters
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18. Power Factor
 Active power (P) It is the useful power that is doing the actual work. It is
measured in W, kW, MW & calculated as, P = S x cos φ
 Reactive power (Q) It is a consequence of an AC system. Reactive power
are used to build up magnetic fields. It is measured in var, kvar, Mvar &
calculated as, Q = S x sin φ or P x tan φ
 Apparent power (S) Or total power (S) is the combination of active and
reactive power. Apparent power is measured in VA, kVA, MVA
 Power factor is a measurement of the efficiency in a system. PF describes
the relationship between active (P) and apparent Power (S) Power Factor
is ratio of the actual electrical power dissipated by an AC circuit to the
product of the r.m.s. values of current and voltage. The difference
between the two is caused by reactance in the circuit and represents
power that does no useful work. Displacement Power Factor
 The displacement power factor is the power factor due to the phase shift
between voltage and current at the fundamental line frequency. For
sinusoidal (non-distorted) currents, the displacement power factor is the
same as the apparent power factor.Inductive loads cause current to lag
behind voltage, while capacitive loads cause current to lead voltage
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19.  In Electrical Engineering, Power Factor is only related to AC Circuits i.e. There is no Power Factor
(P.f) in DC Circuits due to zero frequency.
 Power Factor may be defined by three definitions and formals as follow
 The Cosine of angle between Current and Voltage is called Power Factor.
 P = VI Cosθ OR
 Cosθ = P / V I OR
 Cosθ = kW / kVA OR
 Cosθ = True Power/ Apparent Power
 The ratio between resistance and Impedance is Called Power Factor
 The ratio between Actual Power and Apparent Power is called power factor
 Cosθ = kW / kVA
 The ratio between resistance and Impedance is Called Power Factor
 Cosθ = R/Z
 The ratio between Actual Power and Apparent Power is called power factor
 Cosθ = kW / kVA
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Power Factor (Cosθ)

20. www.sachu.in
Power factor means

21. Automatic Power Factor
Control Panel
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22. Automatic Power factor correction panel (APFC)
 Automatic Power factor correction panel is fully automatic
in operation and can achieve desired power factor under
fluctuating load conditions. Electrical loads such as motors
can cause electrical systems to be very inductive, which
results in very ‘lagging power factor’ i.e. wastage of
energy.
 The simple solution to maintain the power factor in
required range is to connect or disconnect the power
factor correction capacitors. Manual switching is just
impossible for rapidly fluctuating loads and hence an
automatic control system is required which continuously
monitors the power factor and make appropriate
corrections to maintain it within the required range.
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23. Voltage sags
 A voltage sag is a short duration decrease in voltage
values. Voltage sags longer than two minutes are
classified as undervoltages. Common causes of voltage
sags and undervoltages are short circuits (faults) on the
electric power system, motor starting, customer load
additions, and large load additions in the utility service
area.
 Sags can cause computers and other sensitive equipment
to malfunction or simply shut off. Undervoltage
conditions can damage certain types of electrical
equipment.
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24. Distortion (Harmonics)
 Distortion occurs when harmonic frequencies are added to
the 60 Hertz (60Hz) voltage or current waveform, making the
usually smooth wave appear jagged or distorted. Distortion
can be caused by solid state devices such as rectifiers,
adjustable speed controls, fluorescent lights, and even
computers themselves.
 At high levels, distortion can cause computers to
malfunctions and cause motors, transformers, and wires to
heat up excessively. Distortion is probably the most
complicated and least understood of all power disturbances.
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25. Interruptions
 Interruptions occur when voltage levels drop to zero.
Interruptions are classified as momentary, temporary, or
long-term. Momentary interruptions occur when service is
interrupted, but then is automatically restored in less than
two seconds.
 Temporary interruptions occur when service is interrupted
for more than two seconds, but is automatically restored in
less than 2 minutes. Long-term interruptions last longer than
two minutes and may require field work to restore service.
 In some cases, momentary outages may go unnoticed or
cause no apparent problems. However, even momentary
outages can last long enough to shut down computers and
disrupt the operation of sensitive electrical equipment.
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26. Transients
 Transients are sudden but significant deviations from
normal voltage or current levels. Transients typically last
from 200 millionths of a second to half a second.
Transients are typically caused by lightning, electrostatic
discharges, load switching or faulty wiring.
 Transients can erase or alter computer data, resulting in
difficult-to-detect computational errors. In extreme cases,
transients can destroy electronic circuitry and damage
electrical equipment.
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27. Voltage swells
 A voltage swell is a short duration increase in voltage
values. Voltage swells lasting longer than two minutes
are classified as over voltages. Voltage swells and
over voltages are commonly caused by large load
changes and power line switching.
 If swells reach too high a peak, they can damage
electrical equipment. The utility's voltage regulating
equipment may not react quickly enough to prevent all
swells or sags.
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28. Flicker
 Flicker can be defined as small amplitude changes in
voltage levels occurring at frequencies less then 25 Hertz
(25Hz). Flicker is caused by large, rapidly fluctuating loads
such as arc furnaces and electric welders.
 Flicker is rarely harmful to electronic equipment, but is
more of a nuisance because it causes annoying, noticeable
changes in lighting levels.
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29. Harmonics Study
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30. What are Harmonic Studies
 Harmonic studies are performed to determine harmonic
distortion levels and filtering requirements within a facility
and to determine if harmonic voltages and currents are at
acceptable levels. Field measurements and computer
simulations are used to characterize adjustable-speed
drives (ASDs) and other nonlinear loads and simulations
are then performed to determine the filter specifications
and effectiveness.
 The application of harmonic filters will significantly alter
the frequency response of the power system. An
evaluation of the harmonic voltage and current limits,
(e.g., IEEE Std. 519) is completed to determine the
effectiveness of the proposed filter installation.
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31. Why are Harmonic Studies
important
 Avoids damage due to excessive harmonic currents in
transformers and capacitor banks.
 Ensures sensitive electronic equipment will not
malfunction due to excessive harmonic voltage
distortion.
 Satisfies the utility's voltage and current harmonic
distortion requirements.
 Harmonic studies should be considered whenever there
are solid state drivers or electric furnaces and capacitor
banks in the power system.
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32. www.sachu.in
Harmonics Analyser

33. Harmonics Curves
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34. Combined waveform represents fundamental, resulting
and harmonic wave
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35. Current harmonic distortion
standards IEEE-519
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36. Harmonic Mitigation
Techniques Part I
 Reliability issues and costs can be avoided if the proper
harmonic mitigation solution is implemented. Choosing the best
one will depend on the nature of the load and the power demand
of connected equipment.
 Smoothing the flow: reactors and chokes. AC line reactors and
DC link chokes help reduce the level of harmonics on the
electrical system by effectively expanding out and reducing the
peaks caused by a VFD’s inverter. Typically used for applications
up to 500 kW of unit power or 1000 kW of total drives power,
these devices have the added benefit of increasing the lifetime
of each VFD. They are also the most reasonably priced and
compact solution, but less effective at mitigating the harmonic
distortions in total.
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37.  Cancel out the problem: 12-pulse drives. For larger drives above
400 kW, the 12-pulse arrangement is a good option to consider.
This solution uses a 30-degree phase shift transformer, with
the standard output supplying one set of VFDs while the 30-
degree output feeds a second set of VFDs. A 6-pulse converter
bridge connected to each of the outputs enables cancellation
of harmonics. If even greater mitigation is required, 18- and 24-
pulse configurations are possible. Multi-pulse solutions are
most efficient in terms of least power losses, but they are not
simple and require the additional expense of a transformer.
 The low-cost option: passive filters. Combining reactors
(inductors) and capacitors, a passive filter creates a resonant
circuit, tuned to the frequency of the harmonic order you need
to eliminate. Multiple filters can be combined to tackle multiple
harmonics. They are a good, low cost option. However, they
have a low power factor at partial loads and therefore risk
causing resonances within the grid.
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Harmonic Mitigation Techniques Part II

38.  Measure and counteract: active filters. By measuring the harmonics
produced by VFDs in real time, active filters then generate an equivalent
harmonic spectrum, but in reverse phase. When added to the VFD current,
the two harmonic series cancel out. Active filters are installed in parallel
to VFDs, and can be a good moderately priced solution because a single
filter can be used to provide mitigation for several drives that have one
point of coupling. But keep in mind that these filters must also be
oversized to compensate for decreased power factor.
 Swap out the source: low harmonic drive. VFDs designed with an ‘IGBT’
converter on the mains side instead of the typical diode rectifier
consuming sinusoidal current without harmonic currents from the mains.
These are called low harmonic drives, and the result is completely
avoiding the impact of harmonics and idle power on the electrical system.
They are in the midrange in terms of cost and are simpler than an active
filter, but they require more overall space in case of lower power rating
compared with active filter compensating a group of drives.
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Harmonic Mitigation Techniques Part III

39. Active Harmonic Filters (AHF) Types
 AHF Types
 There are three basic types of active harmonic filters based on how they are connected on
the electrical system:
 1. Shunt filter
 It is in parallel with the AC line and is used to remove harmonic distortions caused by
nonlinear loads. Therefore, this type of filter is independent on the load or electrical AC
system characteristics. Subsequently, it needs only to be sized for the harmonic current
drawn by the nonlinear loads.
 2. Series filter
 It is connected in series with the AC distribution network and functions to offset harmonic
distortions that are present in the electrical system. This solution is technically similar to
power line conditioners and should be sized for the total load rating.
 3. Hybrid filter
 This is a combination of an active and a passive filter, and could either of the shunt or
series type. In special cases, it may be a cost-effective solution. Here, the passive filter
performs the basic filtering and the active filter, through its dynamic and precise method,
removes the other harmonics.
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40. AHF (Active Harmonic Filter)
Active Harmonic Filters (AHF) are power quality devices that
monitor the nonlinear load and dynamically provide controlled
current injection, which cancels out the harmonic currents in
the electrical system. They also correct poor displacement
power factor (DPF) by compensating the system’s reactive
current
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41. Major Covered Power Quality
measurement Parameters
 TRMS AC+DC voltage up to 1,000 V
 TRMS AC+DC current: 5 mA to 10 kA depending on the sensors
 Frequency
 Power values: W, VA, var, VAD, PF, DPF, cos φ, tan φ
 Energy values: Wh, varh, VAh, VADh, BTU, toe, Joule
 Harmonics from 0 to the 50th order, phase
 Transients: up to 50
 Inrush over 4 periods
 Recording of a selection of parameters at the maximum sampling rate
for several days to several weeks
 Alarms: 4,000 of 10 different types
 Peak detection
 Vectorial representation
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42. Benefits Of Power Quality Analysis
 Assist in preventative and predictive maintenance
 Identify source and frequency of events
 Establish precise location and timing of events
 Develop maintenance schedules
 Monitor and trend conditions
 Analyze harmonics, Flicker , Transients frequency
variation ,voltage variations (sag & swell .)
 Ensure equipment performance
 Assess sensitivity of process equipment to disturbances
 Evaluate performance against specifications
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43. Advantages of the PQA
 The PQA final report provides a complete picture of the
electrical system’s correct state of operation.
 The report is a tool of primary importance for preventive
maintenance, in that it lists all the measures to be taken
promptly when disturbances are detected, before the
negative impact on production and the running of the
equipment is felt.
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44. Customers
 Plants &Industries
 Power &Generation
 Paper &Pulp
 Oil&Gas
 Petro chemical
 Steel &Mining
 Cement
 Cement and Fertiliser
 Software companies ( Buildings and Towers)
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45. Hyderabad
Cell:09493013535,Email:info@sachu.in, Web site: www.sachu.in
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Please feel free to contact Sachu Technologies