ABSTRACT:
This study examines the use of Unified Power
Quality Conditioner (UPQC) to mitigate the power quality problems existed in
the grid and the harmonics penetrated by the non-linear loads. The UPQC is
supported by the Photovoltaic (PV) and Battery Energy Storage System (BESS) in
this work. Generally, the PV system supplies the active power to the load.
However, if the PV is unable to supply the power then the BESS activates and
provides power especially during the longer-term voltage interruption. The
standalone PV-UPQC system is less reliable compared to a hybrid PV-BESS system
because of its instability and high environment-dependency. Therefore, BESS
will improve the voltage support capability continuously in the longer-term,
reduce the complexity of the DC-link voltage regulation algorithm, and keep
producing clean energy. The phase synchronization operation of the UPQC
controller is directed by a self-tuning filter (STF) integrated with the unit
vector generator (UVG) technique. Implementation of STF will make sure the UPQC
can successfully operate under unbalanced and distorted grid voltage
conditions. Thus, the requirement of a phase-locked loop (PLL) is omitted and
the STF-UVG is utilized to produce the synchronization phases for the series
and shunt active power filter (APF) compensator in UPQC controller. Finally,
the proposed STF-UVG method is compared with the conventional synchronous
references frame (SRF-PLL) method based UPQC to show the significance of the
proposed technique. Several case studies are further considered to validate the
study in MATLAB-Simulink software.
1. Battery Energy Storage System (BESS)
2. Power Quality
3. Self-Tuning filter (STF)
4. Solar Photovoltaic (PV)
5. Unified Power Quality Conditioner (UPQC)
SOFTWARE: MATLAB/SIMULINK
BLOCK DIAGRAM:
FIGURE 1. UPQC system configuratio
EXPECTED SIMULATION RESULTS:
FIGURE 2. Simulation waveform acquired under Case Study 1 for UPQC connecting with PV-BESS, with include (A) three-phase source voltage (B) Injection voltage of Series APF (C) Load Voltage (D) Load Current (E) Injection Current of Shunt APF (F) Source Current.
FIGURE 3. Simulation result acquired under Case Study 1 for UPQC connecting with PV-BESS, with include (A) DC-Link Voltage (B) Current of PV (C) Power of PV (D) Output power of DC-Link (E) Power of BESS (F) SOC of BESS
FIGURE 5. Simulation findings obtained under Case Study 1 for UPQC connecting with PV-BESS (A) Total capacitor voltage (B) Total capacitor current
FIGURE 6. Simulation waveform acquired under Case Study 1 for UPQC connecting without PV-BESS, with include (A) three-phase source voltage (B) Injection voltage of Series APF (C) Load Voltage (D) Load Current (E) Injection Current of Shunt APF (F) Source Current
FIGURE 7. Simulation findings acquired under Case Study 1 for UPQC connecting without PV-BESS, (A) THD for current under voltage harmonic condition (B) THD for current under voltage harmonic with sag condition (C) THD for voltage
FIGURE 8. Simulation findings obtained under Case Study 1 for UPQC without PV-BESS (A) Total capacitor voltage (B) Total capacitor current
FIGURE 9. Simulation waveform acquired under Case Study 2: Scenario A for balance voltage swell and sag condition, with include (A) three-phase source voltage (B) Injection voltage of Series APF (C) Load Voltage (D) Load Current (E) Injection Current of Shunt APF (F) Source Current
FIGURE
10. Simulation finding showing the
detected voltage magnitude under Case study 2: Scenario A for balance voltage
sag and swell condition.
FIGURE
11. Simulation findings acquired under
Case Study 2: Scenario A for balance voltage sag and swell condition, (A) THD
for current under balance voltage sag condition (B) THD for current under
balance voltage swell condition (C) THD for voltage under both conditions
FIGURE 12. Simulation result acquired under Case Study 2: Scenario A for balance voltage sag and swell condition, with include (A) DC-Link Voltage (B) Current of PV (C) Power of PV (D) Output power of DC-Link (E) Power of BESS (F) SOC of BESS
FIGURE
13. Simulation findings showing the
detected synchronization reference phase value in 𝒔𝒊𝒏(𝝎𝒕) and 𝒄𝒐𝒔(𝝎𝒕) under Case study 2: Scenario A for balance voltage swell and sag
condition, with include (A) Detection of synchronization phase by the STF-UVG
(B) Detection of synchronization phase by the conventional SRF-PLL
FIGURE
14. Simulation waveform acquired under
Case Study 2: Scenario B for unbalance voltage swell and sag condition, with
include (A) three-phase source voltage (B) Injection voltage of Series APF (C)
Load Voltage (D) Load Current (E) Injection Current of Shunt APF (F) Source
Current.
FIGURE 15. Simulation findings acquired the detected voltage magnitude under Case study 2: Scenario B for unbalance voltage sag and swell condition.
FIGURE 16. Simulation result acquired under Case Study 2: Scenario B for unbalance voltage sag and swell condition, with include (A) DC-Link Voltage (B) Current of PV (C) Power of PV (D ) Output power of DC-Link (E) Power of BESS (F) SOC of BESS
FIGURE
17. Simulation findings acquired under
Case Study 2: Scenario B for unbalance voltage swell and sag condition, (A) THD
for current under unbalance voltage swell condition (B) THD for current under
unbalance voltage sag condition (C) THD for voltage under both condition
FIGURE 19. Simulation waveform acquired under Case Study 3: Scenario A for voltage
interruption condition, with include (A) three-phase source voltage (B)
Injection voltage of Series APF (C) Load Voltage
FIGURE 20. Simulation findings acquired the detected voltage magnitude under Case study 3: Scenario A for voltage interruption condition
CONCLUSION:
The
construction of three-phase UPQC has been investigated considering the
condition of complex power quality problems which are an amalgamation of
harmonics, voltage swell, and sags, and voltage interruption under unbalanced
and distorted voltage grid condition. Integrating the BESS and PV with the UPQC
provides active power capability to the network. The main benefit of BESS
integrated with UPQC is that it makes the system capable of supplying and
absorbing active power from the PV. Since renewable energy is not completely reliable
because of its environment-dependent feature, integrating a BESS will solve the
lack of renewable energy resources. Finally, it can be figured that the BESS
and PV attached with UPQC can be a good alternative in the distributed
generation to upgrade the power quality of the contemporary distribution
system. The DC-link voltage is stable because of the continuous supply from the
PV-BESS system. Therefore, it can reduce the complexity of the DC-link voltage
regulation algorithm. The STF-UVG technique for synchronization phases is
applied successfully in the shunt and series APF compensator to generate
reference current and voltage. Thus, the UPQC is designed without relying on
the PLL components, and mitigation of current and voltage are achieved successfully
following the grid condition to ensure the system stability and to achieve
almost unity power factor. The implementation of the proposed technique has
confirmed that the grid current harmonics follow the IEEE-519 standard.
Finally, it is worth mentioning that the proposed system can enhance the
overall efficiency of the grid power system.
REFERENCES:
[1] IEEE Standards Coordinating Committee 22 on Power Quality, IEEE Recommended Practice for Monitoring Electric Power Quality, vol. 2009, no. June. 1995.
[2] D. De Yong, S. Bhowmik, and F. Magnago, “Optimized Complex Power Quality Classifier Using One vs. Rest Support Vector Machines,” Energy Power Eng., vol. 09, no. 10, pp. 568–587, 2017.
[3]
A. Javadi, A. Hamadi, L. Woodward, and K. Al-Haddad, “Experimental
Investigation on a Hybrid Series Active Power Compensator to Improve Power
Quality of Typical Households,” IEEE Trans. Ind. Electron., vol. 63, no.
8, pp. 4849–4859, 2016.
[4] A. Javadi, L. Woodward, and K. Al-Haddad, “Real-Time Implementation of a Three-Phase THSeAF Based on a VSC and a P+R Controller to Improve the Power Quality of Weak Distribution Systems,” IEEE Trans. Power Electron., vol. 33, no. 3, pp. 2073–2082, 2018.
[5]
M. A. Mansor, M. M. Othman, I. Musirin, and S. Z. M. Noor, “Dynamic voltage
restorer (DVR) in a complex voltage disturbance compensation,” Int. J. Power
Electron. Drive Syst., vol. 10, no. 4, pp. 2222–2230, 2019.
