What is meant by Unified Power Quality Conditioner (UPQC)?

UPQC performance based on the current source converter (CSC) topology is addressed in this post. Harmonics and sag are reduced using UPQC. The shunt & series active filter eliminates current & voltage problems simultaneously.

Real power transfer is maintained using a common DC link. The reactor links DC. For power quality issues, the photovoltaic system provides  electricity. Shunt and series converter reference current and voltage generation uses phase locked loop & synchronous reference frame theory. Power quality issues are better mitigated by the suggested UPQC-CSC design.

What is Unified Power Quality Conditioner (UPQC)?

Unified power quality conditioners (UPQC) are making it necessary to reduce the voltage and current disturbances that threaten to have an adverse effect on sensitive electrical loads, all while adjusting for the load’s reactive power. Unified power quality conditioners, also known as UPQC, are made up of combined series & shunt active power filters. These filters allow for simultaneously compensation of voltage & current disturbances, in addition to reactive power.

UPQC is a multifunctional power conditioner that can be utilized to

• Correct voltage fluctuations,
• Provide compensation for different voltage disturbances in power sources &
• Block harmonic load current from accessing the power system.

Configuration of UPQC

UPQC is a customised special power tool made to lessen disturbances that interfere with the execution of delicate and/or important loads. With regard to

• Harmonics,
• Reactive power,
• Voltage disturbances, and
• Power-flow regulation,

UPQC has shunt and series compensation capabilities.

A UPQC is made up of two voltage-source converters connected by a single DC connection that can be

• Single-phase,
• Three-phase three-wire, or
• Three-phase four-wire.

Operation of UPQC

Between the source and the essential load at the Power Control Centre (PCC), one converter is linked in series and functions as the voltage-source inverter.

The other converter functions as a current-source inverter and is connected in the shunt at the PCC via a transformer.

The active series converter isolates

• Harmonics,
• Dampens harmonic oscillations, and
• Compensates for the voltage supply disruptions.

The active shunt converter regulates the DC link voltage and corrects for the load current waveform distortions & reactive power.

By addressing issues like

• Harmonic distortions at the utility-consumer PCC,
• Voltage disturbances,
• Voltage regulation,
• Reactive power flow at fundamental and
• Harmonic frequencies,
• Neutral and negative-sequence currents, and
• Harmonic isolation,

UPQC is specifically made to protect the critical load at the point of installation connected to distorted distribution systems.

Features of UPQC

The following features are available on the  (UPQC) for the non-linear & voltage-sensitive loads:

• Utility current quality for the nonlinear loads is improved since the supply current’s harmonic content is reduced.
• Because UPQC satisfies the load’s V_AR requirements, the supply voltage & current are always in the phase, minimizing the need for extra power factor correction hardware.
• Even when there is supply voltage sag, UPQC keeps the load end voltage (V) at the rated value.
• No supplemental  link voltage support is needed for the series compensator because the voltage supplied by UPQC to keep the load end voltage at the proper value is drawn from the same DC link.

Advantages of UPQC

• The UPQC is intended to be one of the most potent solutions for big capacity loads that are sensitive to supply voltage & load current disturbances (or) are out of balance condition.
• UPQC is far more adaptable than any single inverter-based device.
• It can correct for unbalance and distortion in both the source voltage and the load current at the same time, whereas all other devices can only correct for current (or) voltage distortion.
• Because of these factors, the UPQC is often regarded as a successful customized power device for reducing voltage sags & swells.
• In addition to voltage sags & swell compensation, UPQC can include harmonics & power factor correction.

Application of UPQC

• UPQC is applicable in flexible AC transmission system (FACTS) for regulating the voltage, impedance of voltage , active and reactive power controller.

What is PCC?

The voltage & power of the power system are monitored and managed by PCC (Power Control Centre) Panels.

Conclusion

The post that is being presented belongs to the overall topic of the search for innovative methods to enhancing power quality in electrical supply network. In order to account for the harmonic, reactive, and unbalanced interference currents, a parallel active filter was used. The objective of the active filter series was to compensate for harmonically disruptive voltage as well as voltage sags & swells. As a final common solution for the compensation of the all disturbances caused by voltage and current, the UPQC was addressed. The UPQC is a FACTS device capable of efficiently compensating for all voltage and current disturbances.