A PROJECT ON

ENHANCEMENT OF POWER QUALITY IN DISTRIBUTION SYSTEM USING D-

STATCOM

•Power Quality is a term used to broadly encompass the entire scope of interaction among electrical suppliers, the environment, the system sand products energized, and the users of those system sand products. It is more than the delivery of "clean“ electric power that complies with industry standards. It involves them a attainability of that power, the design, selection, and the installation of every piece of hard ware and software in the electrical energy system. Stretching from the generation plant to the utility customer, power quality is a measure of how the elements affect the system as a whole.

POWER QUALITY

POWER QUALITY

THE COMMON POWER QUALITY PROBLEMS

voltage sags

harmonic distortion

low power factor

Voltage sags are one of the most occurring power quality problems. For an industry voltage sags occur more often and cause severe problems and economical losses. Utilities often focus on disturbances from end-user equipment as the main power quality problems Total Harmonic Distortion, or THD is an amplifier or pre-amplifier specification that compares the output signal of the amplifier with the input signal and measures the level differences in harmonic frequencies between the two. The difference is called total harmonic distortion

KEY WORDS

• D-STATCOM

• Methodology

• results and causes • Conclusion

D-STATCOM

VOLTAGE SOURCE CONVERTER CONTROLLER

ENERGY STORAGE CIRCUIT

LCL PASSSIVE FILTER

D-STATCOM

STATCOM is a managing system used on ac power indication system. It is based on energy gadgets present resource inverter and can act as either a resource or mess up of sensitive ac energy to power system.If linked with a power resource. It can also provide effective ac energy. It is participant of the FACTS family.STATCOM is set up to back up power systems that have a bad energy aspect and often inadequate present control.Its most common use is for present balance

D-STATCOM

A voltage-source converter is a power electronic device that connected in shunt or parallel to the system. It can generate a sinusoidal voltage with any required magnitude, frequency and phase angle. The VSC used to either completely replace the voltage or to inject the ‘missing voltage’. The ‘missing voltage’ is the difference between the nominal voltage and the actual.

Voltage Source Converter (VSC)

Suitable adjustment of the phase and magnitude of the D-STATCOM output voltages allows effectives control of active and reactive power exchanges between D-STATCOM and AC system. In addition, the converter is normally based on some kind of energy storage, which will supply the converter with a DC voltage

CONTROLLER

ENERGY STORAGE CIRCUIT

DC source is connected in parallel with the DC capacitor. It carries the input ripple current of the converter and it is the main reactive energy storage element. This DC capacitor could be charged by a battery source or could be recharged by the converter itself.

LCL Passive Filter

METHODOLOGY

TEST SYSTEM

SIMULINK MODEL FOR THE TEST SYSTEM

TEST SYSTEM

Single line diagram of the test system

SIMULINK MODEL OF THE TEST SYSTEM

CASES IN D-STATCOM

Without insertion of D-STATCOM

With insertion of D-STATCOM

D-STATCOM without LCL Passive Filter

D-STATCOM with LCL Passive Filter

Three phase to ground fault

Double line to ground fault

Single line to ground fault Line to line fault

TYPES OF FAULTS IN THE D-STATCOM

Without insertion of D-STATCOM

TPG DPG

a) voltage at load point is 0.6600 p.u b) voltage at load point is 0.7070 p.u

LL

C) voltage at load point is 0.7487 p.u

SLG

D) voltage at load point is 0.8259 p.u

With insertion of D-STATCOM

TPG

(a).voltage at load point is 0.9367 p.u

DLG

(b).voltage at load point is 0.9800 p.u

LL

c).voltage at load point is 1.068 p.u

LG

d).voltage at load point is 0.9837 p.u

D-STATCOM with out LCL filter

harmonic spectrum of distortion output current without LCLPassive Filter

D-STATCOM WITH FILTER

harmonic spectrum of output current with LCL Passive Filter

CONCLUSION

The simulation results show that the voltage sags can be mitigate by inserting D-STATCOM to the distribution system. By adding LCL Passive filter to D-STATCOM, The power factors also increase close to unity. Thus, it can be concluded that by adding D-STATCOM with LCL filter the power quality isimproved.

THANK YOU