GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous) Bachupally, Hyderabad-500 090

POWER QUALITY LAB

EXPERIMENT-1

THE EFFECT OF NONLINEAR LOADS ON POWER QUALITY

BATCH MEMBERS NAMES

Gokaraju Rangaraju Institute of Engineering &Technology Bachupally, Kukatpally, Hyderabad

Telangana - 500090

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous Institute under JNTU Hyderabad) 

 

CERTIFICATE 

This is to certify that it is a bonafide record of practical work done in the power quality Laboratory in II semester of I year during the 

year 2018‐2019 

 

Name: Roll No: Branch: Signature of staff member

  

1.THE EFFECT OF NONLINEAR LOADS ON POWER QUALITY

AIM : To Study the effects of nonlinear loads on Power Quality

TOOLS USED :

1. MATLAB SOFTWARE

2.simpower system tool box

SPECIFICATIONS:

SL.NO ELEMENTS RATING 1 3-PHASE SOURCE 11KV 2 TRANSFORMER 11KV/415V 3 UNIVERSAL BRIDGE 0.6V 4 R-LOAD 30

Table No:1(a)

THEORY &FORMULAE :

The electrical loads have nonlinear behavior at the AC mains. As they draw harmonic currents of various types such as characteristic harmonics, non-characteristic harmonics, inter-harmonics, sub-harmonics, reactive power component of current, fluctuating current, unbalanced currents from the AC mains, these loads are known as nonlinear loads.

Majority of rotating electric machines and magnetic devices such as transformers, reactors, chokes, magnetic ballasts, and soon behave as nonlinear loads due to saturation in their magnetic circuits, geometry such as presence of teeth and slots, winding distribution, air gap asymmetry, and so on. Many fluctuating loads such as furnaces, electric hammers, and frequently switching devices exhibit highly nonlinear behavior as electrical loads. Even non-saturating electrical loads such as power capacitors behave as nonlinear loads at the AC mains and they create a number of power quality problems due to switching and resonance with magnetic components in the system and are overloaded due to harmonic currents caused by the presence of harmonic voltages in the supply system. Moreover, the solid-state control of AC power using diodes, thyristors , and other semiconductor switches is widely used to feed controlled power to electrical loads such as lighting devices with electronic.

  

Some of these nonlinear loads are as follows:

•Fluorescent lighting and other vapor lamps with electronic ballasts

• Switched mode power supplies

• Computers, copiers, and television sets

• Printer, scanners, and fax machines

• High-frequency welding machines

• Fans with electronic regulators

• Microwave ovens and induction heating devices

Power Quality Problems Caused by Nonlinear Loads:

• Increased rms value of the supply current

• Increased losses • Poor power factor

• Poor utilization of distribution system

• Heating of components of distribution system

• Derating of the distribution system

• Interference in communication system

• Mal-operation of protection systems such as relays

FORMULAE:

Crest Factor(CF): Peak value/rms value

Displacement Power factor(DPF):cosΦ1

Distortion Factor(DF): RMS of Fundamental value/RMS of Supply valve

THD: 1

  

A THREE PHASE NON-LINEAR LOAD

ANALYTICAL CALCULATIONS:

A three-phase nonlinear load Shown in figure is fed from a three-phase 415V,50Hz supply system consisting of a diode bridge converter that feeds a resistive load of 30Ω. Calculate (a) fundamental active power drawn by the load, (b)PF, (c) rms value of supply current, (d)DF, (e) rms value of fundamental supply current, (f) peak current of AC mains, and (g) total harmonic distortion of AC source current (THDI).

FIG 1(a): A three-phase converter-based current fed type of nonlinear load

CALCULATIONS:

  

Given supply phase voltage Vs =415/√3 =239.6V (rms). Vsm =239.6√2V=338.85V, frequency of the supply (f)=50Hz, and R=30Ω.

a. The fundamental active power drawn by the load is P = 3{ 2𝛱 3√3 b. PF=P/(3VsIs)

c. The rms value of supply current is Is = 𝑉𝑠/ 𝑅 2𝜋 3√3 /𝜋 / d. DF of supply current=Is1/Is

e. The rms value of the fundamental component of supply current is Is1 ={Vs/(𝑅 π)}(2π +3√3) f. The peak current of AC mains is Ipeak = Vpeak/R

g. The total harmonic distortion of AC source current (THDI)= 1

  

SIMULINK MODEL :

FIG 1(b):SIMULATION OF A THREE PHASE NONLINEAR 'R'LOAD

PARAMETERS:

  

WAVEFORMS :

CURRENT WAVEFORM:

FIG 1(C): A three-Phase input current waveform from simulation

FIG 1(d): A Input Current waveform of Phase "A" from simulation

  

FIG 1(e): A three-Phase Output Current waveform from simulation

VOLTAGE WAVEFORM:

FIG 1(f): A three-Phase Output Voltage waveform from simulation

SIMULATION RESULTS:

TOTAL HARMONIC DISTORTION(THD):

FIG 1(g):Total Harmonics distortion from simulation

  

A SINGLE-PHASE NON-LINEAR LOAD :

ANALYTICAL CALCULATIONS:

A single-phase uncontrolled bridge converter shown in Figure has a RE load with R=5Ω and E=150V.The input AC voltage is Vs =230V at 50Hz. Calculate (a)load average current, (b) rms value of supply current, (c) CF, (d) DF, (e) DPF, (f) PF, and (g) THD.

FIG 1(h): A SINGLE-PHASE NON-LINEAR LOAD

CALCULATIONS:

Given supply voltage vs =230V, Vsm =325.27V, frequency of supply (f)=50Hz, load R=5Ω, and E=150V.

In a single-phase diode bridge converter ,with RE load, the current flows from angle α .

when AC voltage is equal to E to angle β at which AC voltage reduces to E. α =sin , β = π-α .

The conduction angle= β-α .

Active power drawn from the AC mains is P=𝐼 𝑅 𝐸𝐼 = .

  

The rms value of fundamental current from the AC mains is 𝐼 =P/Vs . Supply AC peak current is Ipeak =(Vsm-E)/R.

a. Load average current is I0= 1 𝛱𝑅 }(2𝑉 cos 𝛼 2𝐸𝛼 𝛱𝐸 .

b. The rms value of supply current 𝐼 is rms value of discontinuous current from the AC mains:

𝐼 1 𝛱𝑅 0.5𝑉 𝐸 𝛱 2𝛼 0.5𝑉 sin 2𝛼 4𝑉 𝐸 cos 𝛼 / .

c.CF of Supply Peak Current /rms value of Supply Current=𝐼 𝐼 .

d.DF=rms value of fundamental Supply Current/rms value of Supply Current=𝐼 𝐼 .

e.DPF=cos 𝜃

f.PF=𝑃 𝑉 𝐼 .

g.THD of AC Current={ 𝐼 𝐼 /𝐼 . SIMULATION:

FIG 1(i): SIMULATION OF A SINGLE-PHASE NON-LINEAR LOAD

PARAMETER:

  

CURRENT WAVEFORM:

FIG 1(j): A Single Phase Input Current Of Nonlinear RE Load From Simulation

  

FIG 1(k): A Single Phase Output Current Of Nonlinear RE Load From Simulation

VOLTAGE WAVEFORM:

FIG 1(l) : A Single Phase Output Voltage Of Nonlinear RE Load From Simulation

SIMULATION RESULTS:

TOTAL HARMONIC DISTROTION(THD):

FIG 1(m): Total Harmonics Distortion From Simulation

COMPARISION:

  

A THREE PHASE NONLINEAR LOAD:

SL.NO PARAMETER THEORETICAL SIMULATION

1 2 3

PHASE VOLTAGE

SOURCE CURRENT

THD

Table No:1(b)

A SINGLE -PHASE NONLINEAR LOAD:

SL.NO PARAMETER THEORETICAL PRACTICAL

1 2 3

PHASE VOLTAGE

SOURCE CURRENT

THD

Table.No:1(c)

RESULTS:

  

REFERRENCE: 

1.Power Quality Problems And Mitigation Techniques By Bhim Singh And Ambrish Chandra.

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous) Bachupally , Hyderabad-500 090

POWER QUALITY LAB

EXPERIMENT-2

TO STUDY THE VOLTAGE SAG AND VOLTAGE SWELL WITH PASSIVE LOAD AND DUE TO

STARTING OF INDUCTION MOTOR

BATCH MEMBERS NAMES

Gokaraju Rangaraju Institute of Engineering &Technology Bachupally, Kukatpally, Hyderabad

Telangana - 500090 

GOKARAJU RANGARAJU INSTITUTE OF 

  

ENGINEERING AND TECHNOLOGY

(Autonomous Institute under JNTU Hyderabad) 

 

CERTIFICATE 

This is to certify that it is a bonafide record of practical work done in the power quality Laboratory in II semester of I year during the 

year 2018‐2019 

 

Name: Roll No: Branch: Signature of staff member

  

2. TO STUDY THE VOLTAGE SAG AND VOLTAGE SWELL WITH PASSIVE LOAD AND DUE TO STARTING OF INDUCTION MOTOR  

AIM: To Study The Voltage Sag And The Voltage Swell.

TOOLS REQUIRED:

1.MATLAB SOFTWARE

2.sim power system tool box

SPECIFICATIONS:

SL.NO ELEMENTS RATING 1 3-PHASE SOURCE 11KV 2 TRANSFORMER 11KV/415V 3 CIRCUIT BREAKER

TRANSITION TIME2/50-2/50

Table.No:2(a)

THEORY&FORMULAE:

VOLTAGE SAG: Voltage sags are caused by abrupt increases in loads such as short circuits or faults, motors starting, or electric heaters turning on, or they are caused by abrupt increases in source impedance, typically caused by a loose connection.

VOLTAGE SWELL: Voltage swells are almost always caused by an abrupt reduction in load on a circuit with a poor or damaged voltage regulator, although they can also be caused by a damaged or loose neutral connection.

  

FIG2(a):Voltage Sag And Voltage Swell

FORMULAE:

a) CHANGE IN VOLTAGE DUE SAG:ΔV=Vnormal-Vsag.

b) CHANGE IN VOLTAGE DUE SWELL:ΔV=Vswell-Vnormal.

c)CURRENT DISTORTION: RMS Fundamental Current/RMS Supply Current.

  

SIMULATION:

VOLTAGE SAG:

FIG2(b):The Voltage Sag Due To Passive Load

VOLTAGE SWELL:

 

FIG2(c):The Voltage Swell Due To Passive Load

  

PARAMETERS:

                                          

  

                                

circuit breaker closed for voltage swell circuit breaker open for voltage sag

  

SIMULATION RESULTS:

WAVEFORM:

VOLTAGE SAG:

FIG2(d):The Voltage Sag Waveform Due To Passive Load

VOLTAGE SWELL:

FIG2(e):The Voltage Swell Waveform Due To Passive Load

  

COMPARISION FROM WAVEFORM:

a) NORMAL VOLTAGE =

b)VOLTAGE SAG=

c) CHANGE IN VOLTAGE DUE TO SAG=

e) NORMAL VOLTAGE =

d)VOLTAGE SWELL=

e)CHANGE IN VOLTAGE DUE TO SWELL=

SIMULATION DUE TO INDUCTION MOTOR LOAD:

VOLTAGE SAG:

FIG2(f):The Voltage Sag Due To Induction Motor Load

  

VOLTAGE SWELL:

FIG2(g):The Voltage Swell Due To Induction Motor Load

PARAMETERS:

  

SIMULATION RESULT:

VOLTAGE SAG:

  

FIG2(h):The Voltage Sag Waveform Due To Induction Motor Load

VOLTAGE SWELL:

FIG2(i):The Voltage Swell Waveform Due To Induction Motor Load

RESULT:

 

REFERRENCE: 

1.Power Quality Problems and Mitigation Techniques By Bhim Singh and Ambrish Chandra.

2.Definition Take from google.

 

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous) Bachupally , Hyderabad-500 090

POWER QUALITY LAB

  

EXPERIMENT-3

TO DEMONSTRATE THE VOLTAGE AND CURRENT DISTORTIONS WITH LED LOAD

BATCH MEMBERS NAMES

Gokaraju Rangaraju Institute of Engineering &Technology Bachupally, Kukatpally, Hyderabad

Telangana - 500090

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous Institute under JNTU Hyderabad) 

 

CERTIFICATE 

This is to certify that it is a bonafide record of practical work done in 

  

the power quality Laboratory in II semester of I year during the year 2018‐2019 

 

Name: Roll No: Branch: Signature of staff member

  

3. TO DEMONSTRATE THE VOLTAGE AND CURRENT DISTORTIONS WITH LED LOAD

AIM : To Demonstrate the voltage and current distortions with LED.

TOOLS USED :

1. MATLAB SOFTWARE

2.simpower system tool box

SPECIFICATIONS:

SL.NO ELEMENTS RATING 1 1-PHASE SOURCE 230V 2 UNIVERSAL BRIDGE 0.6V 3 EQUIVALENT CIRCUIT

OF DIODE0.8V/3.1V/10Ω

Table No:3(a)

THEORY &FORMULAE :

Current harmonics are caused by non-linear loads. When a non-linear load, such as a rectifier is connected to the system, it draws a current that is not necessarily sinusoidal. The current waveform can become quite complex, depending on the type of load and its interaction with other components of the system. Regardless of how complex the current waveform becomes, as described through Fourier series analysis, it is possible to deconstruct it into a series of simple sinusoids, which start at the power system fundamental frequency and occur at integer multiples of the fundamental frequency.

EXAMPLES: non-linear loads include common office equipment such as computers and printers, Fluorescent lighting, LED driver, battery chargers and also variable-speed drives.

CURRENT DISTORTIONS:

The rms current contains both the fundamental and harmonics. Note that the value of current at each harmonic as well as that for the rms current are the same at each measuring point, just as in a system containing only fundamental current. The term “distortion rms” is used to denote the rms value of harmonic current with the fundamental left out of the summation. The rms current is basically the total effective load current.

  

FORMULAE:

a. Crest Factor(CF): Peak value/rms value

b. Displacement Power factor(DPF):cosΦ1

c. Distortion Factor(DF): RMS of Fundamental value/RMS of Supply valve

d. THD = 1

SIMULATION WITHOUT FILTER:

FIG 3(a): Simulation of led load without filter.

  

PARAMETERS:

LOAD PARAMETERS:

  

SIMULATION WAVEFORM:

INPUT WAVE FORM OF LED LOAD:

CURRENT WAVEFORM:

FIG 3(b): Simulation of input current waveform of led load .

VOLTAGE WAVEFORM:

FIG 3(c): Simulation of input voltage waveform of led load .

  

OUTPUT WAVE FORM OF LED LOAD:

CURRENT AND VOLTAGE WAVEFORMS:

FIG 3(d): Simulation of output current and voltage waveforms of led load .

SIMULATION RESULTS:

TOTAL HARMONIC DISTORTION (THD) WITH LED LOAD:

FIG 3(e): Total Harmonics distortion from simulation

RESULTS:

REFERRENCE:

[1] Power Quality Problems and Mitigation Techniques By Bhim Singh and Ambrish Chandra.

[2] Definition Take from google.

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous) Bachupally , Hyderabad-500 090

POWER QUALITY LAB

EXPERIMENT-4

TO REDUCE THE CURRENT HARMONICS WITH FILTERS

BATCH MEMBERS NAMES

Gokaraju Rangaraju Institute of Engineering &Technology Bachupally, Kukatpally, Hyderabad

Telangana - 500090

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous Institute under JNTU Hyderabad) 

 

CERTIFICATE 

This is to certify that it is a bonafide record of practical work done in the power quality Laboratory in II semester of I year during the 

year 2018‐2019 

 

Name: Roll No: Branch: Signature of staff member

  

4. TO REDUCE THE CURRENT HARMONICS WITH FILTERS

AIM: To reduce the current harmonics with filters.

TOOLS USED:

1. MATLAB SOFTWARE

2. Simpower system tool box

SPECIFICATIONS:

SL.NO ELEMENTS RATING 1 1-PHASE SOURCE 230V 2 FILTER CIRCUIT(L,C,R) 1.87H/0.6μf/2.5KΩ 3 UNIVERSAL BRIDGE 0.6V 4 EQUIVALENT CIRCUIT

OF DIODE0.8V/3.1V/10Ω

Table No: 4(a)

THEORY & FORMULAE:

Current harmonics are caused by non-linear loads. When a non-linear load, such as a rectifier is connected to the system, it draws a current that is not necessarily sinusoidal. The current waveform can become quite complex, depending on the type of load and its interaction with other components of the system. Regardless of how complex the current waveform becomes, as described through Fourier series analysis, it is possible to deconstruct it into a series of simple sinusoids, which start at the power system fundamental frequency and occur at integer multiples of the fundamental frequency.

EXAMPLES: non-linear loads include common office equipment such as computers and printers, Fluorescent lighting, battery chargers and also variable-speed drives.

FILTERS: A filter is a device or process that removes some unwanted components or features from a signal. Filtering is a class of signal processing, the defining feature of filters being the complete or partial suppression of some aspect of the signal. Most often, this means removing some frequencies or frequency bands. However, filters do not exclusively act in the frequency domain; especially in the field of image processing many other targets for filtering exist. Correlations can be removed for certain frequency.

  

SOME OF FILTERS:

1. Active filters.

2. Passive filters.

ACTIVE FILTERS: Active filters are a group of electronic filters that utilizes active components like an amplifier for its functioning. Amplifiers are used in filters for designing to enhance the predictability and performance. This is all finished while keeping away from the need of the inductors. Usually, the filter characteristics can be determined by using an amplifier. This article presents a detailed study and usage of active filters in modern technology. In future, the various types of active filters will have a much wider capacity and will signify the future technology than it has at the present.

TYPES OF ACTIVE FILTERS:

The most common types of active filters are classified into four such as

a. Butterworth

b. Chebyshev

c. Bessel

d. Elliptical

PASSIVE FILTERS:

Frequency-selective or filter circuits pass to the output only those input signals that are in a desired range of frequencies (called pass band). The amplitude of signals outside this range of frequencies (called stop band) is reduced (ideally reduced to zero). Typically in these circuits, the input and output currents are kept to a small value and as such, the current transfer function is not an important parameter.

TYPES OF PASSIVE FILTERS:

a. Low pass filter.

b. High pass filter.

c. Band pass filter & Band stop filter.

d. Sinusoidal filter.

e. Signal filter.

  

FORMULAE:

a. Crest Factor(CF): Peak value/rms value

b. Displacement Power factor(DPF):cosΦ1

c. Distortion Factor(DF): RMS of Fundamental value/RMS of Supply valve

d. THD = 1

e. Resonance Frequency 𝑓 = √

FILTER RESONANCE FREQUENCY:

Where:

𝑓 = √

SIMULATION WITH FILTER:

FIG 4(a): Simulation of led load with filter

  

PARAMETERS:

LOAD PARAMETERS:

  

FILTER PARAMETER:

Capacitor value:

  

Resistor value:

SIMULATION WAVEFORM:

INPUT WAVE FORM WITH FILTER:

CURRENT WAVEFORM:

FIG 4(b): Simulation of input current waveform of led load with filter.

VOLTAGE WAVEFORM:

FIG 4(c): Simulation of input voltage waveform of led load with filter.

  

OUTPUT WAVE FORM WITH FILTER:

CURRENT WAVEFORM and VOLTAGE WAVEFORMS:

FIG 4(d): Simulation of output current and voltage waveforms of led load with filter.

SIMULATION RESULTS:

TOTAL HARMONIC DISTORTION (THD) WITH FILTER:

FIG 4(e): Total Harmonics distortion from simulation

RESULTS:

REFERRENCE:

[1] Fajar Abdul Karim, Mohamad Ramdhani ,  Ekki Kurniawan,"  Low Pass Filter Installation for Reducing Harmonic Current Emissions From LED Lamps Based on EMC Standard", IEEE 2016.

[2] / www.elprocus.com/ types-active

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous) Bachupally , Hyderabad-500 090

POWER QUALITY LAB

EXPERIMENT-5

TO STUDY THE CAPACITOR SWITCHING TRANSIENTS

BATCH MEMBERS NAMES

Gokaraju Rangaraju Institute of Engineering &Technology Bachupally, Kukatpally, Hyderabad

Telangana - 500090

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous Institute under JNTU Hyderabad) 

 

CERTIFICATE 

This is to certify that it is a bonafide record of practical work done in the power quality Laboratory in II semester of I year during the 

year 2018‐2019 

 

Name: Roll No: Branch: Signature of staff member

  

5. TO STUDY THE CAPACITOR SWITCHING TRANSIENTS

AIM: To study the capacitor switching transients.

TOOLS USED:

1. MATLAB SOFTWARE

2. Simpower system tool box

SPECIFICATIONS:

SL.NO ELEMENTS RATING 1 1-PHASE SOURCE 230V 2 SUPER CAPACITOR 58F/16.62V 3 UNIVERSAL BRIDGE 0.6V 4 RESISTOR LOAD 10Ω 5 Circuit breaker 20/50,60/50

Table No: 5(a)

THEORY:

A Supercapacitor (SC) (also called a supercap, ultracapacitor or Goldcap )is a high-capacity capacitor with capacitance values much higher than other capacitors (but lower voltage limits) that bridge the gap between electrolytic capacitors and rechargeable batteries. They typically store 10 to 100 times more energy per unit volume or mass than electrolytic capacitors, can accept and deliver charge much faster than batteries, and tolerate many more charge and discharge cycles than rechargeable batteries. Supercapacitor are used in applications requiring many rapid charge/discharge cycles rather than long term compact energy storage: within cars, buses, trains, cranes and elevators, where they are used for regenerative braking, short-term energy storage or burst-mode power delivery. Smaller units are used as memory backup for static random-access memory (SRAM).

  

CONSTRUCTION OF SUPERCAPACITOR:

FIG 5(a): Construction of super capacitor

ADVANTAGES OF SUPER CAPACITOR:

1. Supercapacitor combines the energy storage properties of batteries with the power discharge characteristics of capacitors.

2. Supercapacitor can be charged quickly, leading to a very high power density, and do not lose their storage capabilities over time.

3. Very high cycle count- discharge takes milliseconds up to several minutes and can be charged in seconds to minutes.

4. Virtually unlimited cycle life, can be cycled millions of time.

5. Simple charging; draws only what it needs; not subject to over charge.

6. Life Li-ion battery (5-10years), Supercapacitor (10-15years).

  

7. Charge temperature Li-ion battery: 0 to 45 C , Supercapacitor: -40 to 65 C. 8. Supercapacitor have very fast transient response as compared to the commonly available lithium ion batteries (20 micro seconds).

9. Provides peak power (or) backup power.

10. Reduce battery size, weight and cost energy.

SIMULATION WITH NORMAL CAPACITOR:

WITH AC SOURCE:

FIG 5(b): Simulation of capacitor switching with AC source.

  

WITH DC SOURCE:

FIG 5(c): Simulation of capacitor switching with DC source.

PARAMETERS:

  

LOAD PARAMETERS:

SIMULATION RESULT OF NORMAL CAPACITOR:

INPUT WAVEFORM WITH AC SOURCE:

CURRENT WAVE FORM WITH AC SOURCE:

FIG 5(d): Simulation of input current waveform with AC source.

  

VOLTAGE WAVEFORM WITH AC SOURCE:

FIG 5(e): Simulation of input voltage waveform with AC source.

CAPACITOR VOLTAGE WAVEFORM WITH AC SOURCE:

FIG 5(f): Simulation of capacitor voltage waveform with AC source.

  

INPUT WAVEFORM WITH DC SOURCE:

CURRENT AND VOLTAGE WAVE FORMS WITH DC SOURCE:

FIG 5(g): Simulation of input current and voltage waveforms with DC source

CAPACITOR VOLTAGE WAVEFORM WITH DC SOURCE:

FIG 5(h): Simulation of capacitor voltage waveform with DC source.

  

SIMULATION WITH SUPER CAPACITOR:

FIG 5(i): Simulation of super capacitor switching with DC source.

LOAD PARAMETERS:

  

SIMULATION RESULT WITH SUPER CAPACITOR:

INPUT WAVEFORM WITH SUPER CAPACITOR:

CURRENT AND VOLTAGE WAVEFORMS:

FIG 5(j): Simulation of super capacitor input current and voltage waveforms with DC source

SUPER CAPACITOR VOLTAGE WAVEFORM:

FIG 5(k): Simulation of super capacitor voltage waveform (during charging) .

  

OBSERVATION:

1.fig5(d) , fig5(g) is input current waveform of AC&DC source of normal capacitor respectively ,were compared with, fig5(j) input current waveform of super capacitor with DC source. The super capacitor gives fast transient response during switching compared to normal capacitor.

2. fig5(f) , fig5(h) is voltage waveform across normal capacitor & fig5(k) is voltage waveform across super capacitor. The super capacitor charge in less time with more storage of energy compared to normal capacitor.

3. Supercapacitor rating is more (1F to >10000F) compared to normal capacitor.

4. Supercapacitor were used in EV's.

RESULT:

REFERRENCE:

[1] Pankaj Govind Hiray, B. E. Kushare,'' Controller Design for Super capacitor as Energy Storage in Medium Voltage AC System'' , International Journal of Advanced Computer Research , vol-3, 2013.

[2] From Google search engine.

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous) Bachupally, Hyderabad-500 090

POWER QUALITY LAB

EXPERIMENT-6

TO STUDY THE CURRENT HARMONICS IN BLDC MOTOR

BATCH MEMBERS NAMES

Gokaraju Rangaraju Institute of Engineering &Technology Bachupally, Kukatpally, Hyderabad

Telangana - 500090

  

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY

(Autonomous Institute under JNTU Hyderabad) 

 

CERTIFICATE 

This is to certify that it is a bonafide record of practical work done in the power quality Laboratory in II semester of I year during the 

year 2018‐2019 

 

Name: Roll No: Branch: Signature of staff member

  

6. TO STUDY THE CURRENT HARMONICS IN BLDC

AIM : To study the current harmonics in bldc motor.

TOOLS USED :

1. MATLAB SOFTWARE

2.simpower system tool box

SPECIFICATIONS:

SL.NO ELEMENTS RATING 1 3-PHASE SOURCE 415V 2 3-PHASE V-I

MEASUREMENT -

3 UNIVERSAL BRIDGE 0.6V 4 BLDC MOTOR 120V(FLAT AREA)

Table No:6(a)

THEORY :

A BLDC motor accomplishes commutation electronically using rotor position feedback to determine when to switch the current. The structure is shown in Figure 9(b). Feedback usually entails an attached Hall sensor or a rotary encoder. The stator windings work in conjunction with permanent magnets on the rotor to generate a nearly uniform flux density in the air gap. This permits the stator coils to be driven by a constant DC voltage (hence the name brushless DC), which simply switches from one stator coil to the next to generate an AC voltage waveform with a trapezoidal shape.

  

FIG 6(a): Construction of trapezoidal back emf of BLDC motor

BLDC DRIVE CIRCUIT:

FIG 6(b): A circuit of BLDC motor drive control.

  

HALL SENSORS SIGNALS AND BACK EMF WAVEFORMS:

FIG 6(c): waveform of hall sensor signal and back emf of bldc motor.

FORMULAE:

Crest Factor(CF): Peak value/rms value

Displacement Power factor(DPF):cosΦ1

Distortion Factor(DF): RMS of Fundamental value/RMS of Supply valve.

THD: 1

  

ADVANTAGES OF BLDC MOTOR:

Better speed versus torque characteristics High dynamic response High efficiency Long operating life due to a lack of electrical and friction losses Noiseless operation Higher speed ranges APPLICATIONS: The cost of the Brushless DC Motor has declined since its presentation, because of progressions in materials and design. This decrease in cost, coupled with the numerous focal points it has over the Brush DC Motor, makes the Brushless DC Motor a popular component in numerous distinctive applications. Applications that use the BLDC Motor include, yet are not constrained to:

Consumer electronics Transport Heating and ventilation Industrial engineering Model engineering SIMULATION OF BLDC MOTOR:

FIG 6(d): simulation diagram of bldc motor. WAVEFORM OF BLDC:

  

INPUT WAVEFORM: CURRENT WAVEFORM: FIG 6(e): input current waveform of bldc motor. VOLTAGE WAVEFORM: FIG 6(f): input voltage waveform of bldc motor. SIMULATION RESULTS:

TOTAL HARMONIC DISTORTION(THD):

FIG 6(g): Total Harmonics distortion from simulation.

  

RESULTS: